Regulation of cellular responses to X-ray irradiation through the activation of lysophosphatidic acid (LPA) receptor-3 (LPA3) and LPA2 in osteosarcoma cells

Lysophosphatidic acid (LPA) binds to its specific G protein-coupled LPA receptors (LPA1 to LPA6), resulting in the activation of various cellular functions. LPA receptor-mediated signaling facilitates tumor progression in human malignancies. In the present study, we investigated whether LPA receptor-mediated signaling contributes to cellular responses to X-ray irradiation in osteosarcoma MG-63 cells. After X-ray irradiation (2, 4 and 8 Gy), LPAR2 and LPAR3 expression levels in MG-63 cells were significantly elevated in a dose-dependent manner, but no change of LPAR1 expression level was observed. The cell growth activities of MG-63 cells irradiated with X-rays (2, 4 and 8 Gy) were reduced by LPA. Conversely, LPA3 agonist (2 S)-OMPT enhanced the cell growth activities of X-ray irradiated MG-63 cells. The cell movement of MG-63 cells exposed to X-ray irradiation (8 Gy) was inhibited by (2 S)OMPT. In cell survival assay, (2 S)-OMPT suppressed the cell survival to cisplatin (CDDP) of MG-63 cells irradiated with X-rays (8 Gy). The cell survival to CDDP of X-ray irradiated cells was elevated by LPA3 knockdown. Moreover, we evaluated the effects of LPA2 on the cell survival to CDDP of MG-63 cells exposed to X-ray irradiation (8 Gy). The cell survival to CDDP of X-ray irradiated cells was increased by LPA2 agonist GRI-977143 and reduced by LPA2 knockdown. These results suggest that LPA receptor-signaling participates in the modulation of cellular functions induced by X-ray irradiation in osteosarcoma cells.

Lysophosphatidic acid (LPA) receptor-mediated signaling and cellular responses to anticancer drugs and radiation of cancer cells

Lysophosphatidic acid (LPA) is a simple physiological lipid and structurally consists of a fatty, a phosphate and a glycerol. LPA binds to G protein-coupled LPA receptors (LPA1 to LPA6). LPA receptor-mediated signaling mediates a variety of biological responses, such as cell growth, migration, morphogenesis, differentiation and protection from apoptosis. It is considered that LPA receptor-mediated signaling plays an important role in the pathogenesis of human malignancies. So far, genetic and epigenetic alterations of LPA receptors have been found in several cancer cells as well as abnormal LPA production. In addition, LPA receptor-mediated signaling regulates the promotion of malignant behaviors, including chemo- and/or radiation-resistance. Chemotherapy and radiotherapy are the common approaches to the treatments of cancers. However, resistance to anticancer drugs and irradiation is the most critical limitation for chemotherapy and radiotherapy. In this review, we provide the roles of LPA receptor-mediated signaling in the regulation of cellular responses induced by chemotherapeutic agents and irradiation and its biological utility as a possible molecular target for improving cancer cell responses to chemotherapy and radiotherapy.

Immunogenicity and reactogenicity of modified vaccinia Ankara pre-exposure vaccination against mpox according to previous smallpox vaccine exposure and HIV infection: prospective cohort study

Background

Pre-exposure vaccination with MVA-BN has been widely used against mpox to contain the 2022 outbreak. Many countries have defined prioritized strategies, administering a single dose to those historically vaccinated for smallpox, to achieve quickly adequate coverage in front of low supplies. Using epidemiological models, real-life effectiveness was estimated at approximately 36%-86%, but no clinical trials were performed. Few data on MVA-BN immunogenicity are currently available, and there are no established correlates of protection. Immunological response in PLWH in the context of the 2022 outbreak was also poorly described.

Methods

Blood samples were collected from participants eligible for pre-exposure MVA-BN vaccination before (T1) receiving a full course of vaccine (single-dose for vaccine-experienced or smallpox-primed and two-dose for smallpox vaccine-naïve or smallpox non-primed) and one month after the last dose (T2 and T3, respectively). MPXV-specific IgGs were measured by in-house immunofluorescence assay, using 1:20 as screening dilution, MPXV-specific nAbs by 50% plaque reduction neutralization test (PRNT50, starting dilution 1:10), and IFN-γ-producing specific T cells to MVA-BN vaccine, by ELISpot assay. Paired or unpaired t-test and Wilcoxon or Mann-Whitney test were used to analyse IgG and nAbs, and T-cell response, as appropriate. The probability of IgG and nAb response in vaccine-experienced vs. vaccine-naïve was estimated in participants not reactive at T1. The McNemar test was used to evaluate vaccination's effect on humoral response both overall and by smallpox vaccination history. In participants who were not reactive at T1, the proportion of becoming responders one month after full-cycle completion by exposure groups was compared by logistic regression and then analysed by HIV status strata (interaction test). The response was also examined in continuous, and the Average Treatment Effect (ATE) of the difference from baseline to schedule completion according to previous smallpox vaccination was estimated after weighting for HIV using a linear regression model. Self-reports of adverse effects following immunization (AEFIs) were prospectively collected after the first MVA-BN dose (T1). Systemic (S-AEFIs: fatigue, myalgia, headache, GI effects, chills) and local (L-AEFIs: redness, swelling, pain) AEFIs were graded as absent (grade 0), mild (1), moderate (2), or severe (3). The maximum level of severity for S-AEFIs and L-AEFIs ever experienced over the 30 days post-dose by vaccination exposure groups were analysed using a univariable multinomial logistic regression model and after adjusting for HIV status; for each of the symptoms, we also compared the mean duration by exposure group using an unpaired t-test.

Findings

Among the 164 participants included, 90 (54.8%) were smallpox vaccine-experienced. Median age was 49 years (IQR 41-55). Among the 76 (46%) PLWH, 76% had a CD4 count >500 cells/μL. There was evidence that both the IgG and nAbs titers increased after administration of the MVA-BN vaccine. However, there was no evidence for a difference in the potential mean change in humoral response from baseline to the completion of a full cycle when comparing primed vs. non-primed participants. Similarly, there was no evidence for a difference in the seroconversion rate after full cycle vaccination in the subset of participants not reactive for nAbs at T1 (p = 1.00 by Fisher's exact test). In this same analysis and for the nAbs outcome, there was some evidence of negative effect modification by HIV (interaction p-value = 0.17) as primed people living with HIV (PLWH) showed a lower probability of seroconversion vs. non-primed, and the opposite was seen in PLWoH. When evaluating the response in continuous, we observed an increase in T-cell response after MVA-BN vaccination in both primed and non-primed. There was evidence for a larger increase when using the 2-dose vs. one-dose strategy with a mean difference of -2.01 log2 (p ≤ 0.0001), after controlling for HIV. No evidence for a difference in the risk of developing any AEFIs of any grade were observed by exposure group, except for the lower risk of grade 2 (moderate) fatigue, induration and local pain which was lower in primed vs. non-primed [OR 0.26 (0.08-0.92), p = 0.037; OR 0.30 (0.10-0.88), p = 0.029 and OR 0.19 (0.05-0.73), p = 0.015, respectively]. No evidence for a difference in symptom duration was also detected between the groups.

Interpretation

The evaluation of the humoral and cellular response one month after the completion of the vaccination cycle suggested that MVA-BN is immunogenic and that the administration of a two-dose schedule is preferable regardless of the previous smallpox vaccination history, especially in PLWH, to maximize nAbs response. MVA-BN was safe as well tolerated, with grade 2 reactogenicity higher after the first administration in vaccine-naïve than in vaccine-experienced individuals, but with no evidence for a difference in the duration of these adverse effects. Further studies are needed to evaluate the long-term duration of immunity and to establish specific correlates of protection.

Funding

The study was supported by the National Institute for Infectious Disease Lazzaro Spallanzani IRCCS "Advanced grant 5 × 1000, 2021" and by the Italian Ministry of Health "Ricerca Corrente Linea 2".

GelMA-catechol coated FeHAp nanorods functionalized nanofibrous reinforced bio-instructive and mechanically robust composite hydrogel scaffold for bone tissue engineering

Critical bone defects complicate tissue graft-based surgeries, raising healthcare expenditures and underscoring scaffold-based tissue-engineering strategies to support bone reconstruction. Our study highlighted that the phase-compatible combination of inorganic nanorods, nanofibers, and hydrogels is promising for developing biomimetic and cell-instructive scaffolds since the bone matrix is a porous organic/inorganic composite. In brief, methacrylated gelatin (GelMA) was reacted with dopamine to form catechol-modified GeLMA (GelMA-C). The GelMA-C was nanocoated onto an iron-doped hydroxyapatite (FeHAp) nanorod via metal-catechol network coordination. The modified nanorod (FeHAp@GelMA-C) was loaded onto GelMA-based nanofibers. The nanorods loaded pre-fibers were electrospun onto GelMA solution and photochemically crosslinked to fabricate a fiber-reinforced hydrogel. The structural, mechanical, physicochemical, biocompatibility, swelling properties, osteogenic potential, and bone remodelling potential (using rat femoral defect model) of modified nanorods, simple hydrogel, and nanorod-loaded fiber-reinforced hydrogel were studied. The results supported that the interface interaction between GelMA-C/nanorods, nanorods/nanofibers, nanorods/hydrogels, and nanofiber/hydrogels significantly improved the microstructural and mechanical properties of the scaffold. Compared to pristine hydrogel, the nanorod-loaded fiber-reinforced scaffold better supported cellular responses, osteogenic differentiation, matrix mineralization, and accelerated bone regeneration. The nanorod-loaded fiber-reinforced hydrogel proved more biomimetic and cell-instructive for guided bone reconstruction.

Approaches to evaluate the specific immune responses to SARS-CoV-2

The SARS-CoV-2 pandemic has a huge impact on public health and global economy, meaning an enormous scientific, political, and social challenge. Studying how infection or vaccination triggers both cellular and humoral responses is essential to know the grade and length of protection generated in the population. Nowadays, scientists and authorities around the world are increasingly concerned about the arrival of new variants, which have a greater spread, due to the high mutation rate of this virus. The aim of this review is to summarize the different techniques available for the study of the immune responses after exposure or vaccination against SARS-CoV-2, showing their advantages and limitations, and proposing suitable combinations of different techniques to achieve extensive information in these studies. We wish that the information provided here will helps other scientists in their studies of the immune response against SARS-CoV-2 after vaccination with new vaccine candidates or infection with upcoming variants.

On the mechanism of tissue-selective gene delivery by lipid nanoparticles

The era of nucleic acid nanomedicine has arrived, as evidenced by Patisiran, a small interfering RNA (siRNA) encapsulated lipid nanoparticle (LNP), and mRNA-loaded LNPs used in COVID-19 vaccines. The diversity of nano-designs for delivering nucleic acid molecules tested in Phase II/III clinical trials reflects the potential of these technologies. These breakthroughs in non-viral gene delivery, including the use of LNPs, have attracted substantial interest worldwide for developing more effective drugs. A next step in this field is to target tissues other than the liver, which requires significant research efforts and material development. However, mechanistic studies in this area are lacking. This study compares two types of LNPs with different tissue-selectivity for delivering plasmid DNA (pDNA), one being liver-selective and the other spleen-selective, in an effort to understand the mechanisms responsible for differences in gene expression of delivered genes. We observed little difference in the biodistribution of these two LNPs despite the 100-1000-fold differences in gene expression. We then quantified the amount of delivered pDNA and mRNA expression in each tissue by quantitative real-time PCR (qPCR) to evaluate various intracellular processes, such as nuclear delivery, transcription and translation. The results showed a >100-fold difference in the translation step but there were little differences in amount of pDNA delivered to the nucleus or the amount of mRNA expression for the two LNP deliveries. Our findings suggest that endogenous factors affect gene expression efficiency not the extent of biodistribution.

Molecular interaction mechanisms and cellular response of superoxide dismutase and catalase to fluoranthene

As an important raw material and intermediate product of the petrochemical industry, fluoranthene (Fla) can be emitted with industrial activities and has become a typical polycyclic aromatic hydrocarbon enriched in the Chinese topsoil layer, posing a significant threat to sensitive soil biota. Here, multispectral tools and molecular simulation techniques were integrated to elucidate the molecular mechanism of Fla interaction with key antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) at the molecular level. Meanwhile, we further revealed the cellular responses of SOD and CAT and the associated redox states in earthworm (Eisenia fetida) coelomocytes based on the molecular-level results. Our results showed that the exposure to Fla affected the backbone structure of SOD and CAT molecules and resulted in the formation of Fla-SOD polymers as well as an overall reduction in the size of the Fla-CAT binding system. Fla altered the microenvironment around Tyr residues in the SOD molecule and quenched the endogenous fluorescence of Tyr within the CAT molecule. In earthworm coelomocytes, Fla at 60 and 80 μM resulted in a significant elevation of CAT and SOD activities by 114% (p = 0.032) and 6.09% (p = 0.013), respectively. Molecular simulation results suggested that Fla-induced changes in the structure and conformation of SOD and CAT may be the key reason for their altered activities. The related redox homeostasis detection in earthworm coelomocytes indicated that high concentrations (80 μM) of Fla led to a significant accumulation of intracellular ROS (p = 0.018) and resulted in the development of lipid peroxidation. Our work contributes to an in-depth understanding of the biological effect of Fla to sensitive soil fauna, thus providing new ideas for Fla ecological risk prevention and control.

mRNA-1273 SARS-CoV-2 vaccine in recently transplanted allogeneic hematopoietic cell transplant recipients: Dynamics of cellular and humoral immune responses and booster effect

Allogeneic hematopoietic stem cell transplant (HCT) recipients are at high risk of severe COVID-19 despite vaccination. Little is known about cellular response to SARS-CoV-2 vaccine in this population, especially in recently transplanted patients (RTP). In this single-center study we examined cellular and humoral response to the mRNA-1273 (Spikevax®) vaccine in recently transplanted patients (RTP, n = 49), and compared them to long-term transplanted patients (LTTP, n = 19) and healthy controls (n = 20) at three different timepoints: one and three months after the second dose (T1 and T2, respectively, 28 days apart), and one month after the third dose (T3). Controls did not receive a third dose. RTPs showed lower IgG anti-S1 titers than healthy controls at both T1 (mean 0.50 vs 0.94 arbitrary units -AU-, p < 0.0001) and T2 (0.37 vs 0.79 AU, p < 0.0001). They also presented lower titers than LTTPs at T1 (0.50 vs 0.66, p = 0.01), but no differences at T2 (0.37 vs 0.40 AU, p = 0.55). The rate of positive T-cell responses was lower in RTPs than in controls at both T1 and T2 (61.2 % vs 95 %, p = 0.007; 59.2 % vs 100 %, p = 0.001, respectively), but without statistically significant differences between transplanted groups. At T3 no differences were seen between RTPs and LTTPs as well, neither in IgG antibodies (p = 0.82) nor in cellular responses (p = 0.15), although a third dose increased the rate of positive cellular and humoral responses in approximately 50 % of recently transplanted patients. However, active immunosuppressive treatment severely diminished their chances to produce an adequate response.

Impact of methotrexate treatment on vaccines immunogenicity in adult rheumatological patients - Lessons learned from the COVID-19 pandemic

Despite the development of new biological and synthetic targeted therapies, methotrexate remains one of the most commonly used immunomodulatory drugs in rheumatology. However, its effect on the immunogenicity of vaccines has been studied only to a limited extent until recently, resulting in the lack of clear guidelines on the use of methotrexate during vaccination. Significant progress was made during the COVID-19 pandemic due to the dynamic development of research on vaccines, including patients with autoimmune inflammatory rheumatic diseases. In the following literature review, we present a summary of what we know so far on the impact of methotrexate on post-vaccination response in adult rheumatology patients, taking into account the lessons learned from the COVID-19 pandemic. Studies on the effect of methotrexate on the immunogenicity of influenza, pneumococcal, herpes zoster, tetanus/diphtheria/pertussis, hepatitis A, yellow fever, and COVID-19 vaccines are described in detail, including the effect of methotrexate on the humoral and cellular response of individual vaccines. The available evidence for recommendations for withholding methotrexate in the post-vaccination period is presented. Lastly, an overview of potential immunological mechanisms through which MTX modulates the immunogenicity of vaccinations is also provided.

Functional homology of tachykinin signalling: The influence of human substance P on the immune system of the mealworm beetle, Tenebrio molitor L

Tachykinin-related peptides (TRPs) are one of the most prominent families of neuropeptides in the animal kingdom. Insect TRPs display strong structural and functional homology to vertebrate tachykinins (TKs). To study functional homologies between these two neuropeptide families, the influence of human substance P (SP, one of the essential vertebrate TKs) on the immune system of the mealworm beetle, Tenebrio molitor L., was analysed. Human SP influences the phagocytic abilities of T. molitor haemocytes. Peptide injection leads to an increase in the number of haemocytes participating in the phagocytosis of latex beads. In contrast, incubation of haemocytes from non-injected beetles in a solution of physiological saline and SP causes a decrease in phagocytic activity. Treatment with human SP also led to increased adhesion of haemocytes, but no changes in the arrangement of the F-actin cytoskeleton were observed. Interestingly, 6 h after human SP injection, increased DNA integrity in T. molitor haemocytes was reported. The opposite effects were observed 24 h after SP injection. Human SP caused the upregulation of humoral immune responses, such as phenoloxidase (PO) activity in the T. molitor haemolymph, and the downregulation of immune-related genes encoding coleoptericin A, tenecin 3 and Toll receptor. However, genes encoding attacin 2 and cecropin were upregulated. Despite these differences, the antimicrobial activity of T. molitor haemolymph was significantly lower in beetles injected with SP than in control beetles. Moreover, an analysis of the direct influence of SP on lysozyme activity was performed. Our results suggest that SP at a concentration of 10^-6 M can directly inhibit lysozyme activity. However, an opposite effect was reported after the application of SP at a concentration of 10^-4 M. The presented results suggest structural and functional homology between TK signalling in vertebrates and insects. Primarily, this was visible in the context of the humoral response and general antimicrobial activity of T. molitor haemolymph. However, some of the results related to haemocyte function may also indicate the importance of the TK and TRP sequences for evoking immunological effects.

Efficacy and safety of booster vaccination against SARS-CoV-2 in dialysis and renal transplant patients: systematic review and meta-analysis

INTRODUCTION

Patients under renal replacement therapy are at an increased risk of severe infection with SARS-CoV-2, and have been known to have impaired response to standard vaccination. This systematic review and meta-analysis aims at evaluating the efficacy of booster dose vaccination in this population.

METHODS

A systematic review has been conducted to find trials on the booster dose vaccination in kidney transplant recipients (KTRs) or patients under dialysis. Data of seroconversion rates at different timepoints, especially 1 month prior and post-booster dose vaccination have been collected and analyzed. Effects of different factors including type of renal replacement therapy (RRT), vaccine type and brands, magnitude of response to the standard vaccination, and immunosuppression drugs on the response rates have been investigated. Meta-analyses were performed using software Stata v.17.

RESULTS

Overall 58 studies were included. Both RRT patient subgroups represented significant seroconversion, post- (versus pre-) booster dose vaccination, but only in KTRs the booster dose seroconversion surpassed that of the standard protocol. T-cell response was also significantly augmented after booster vaccination, with no difference between the RRT subgroups. mRNA and vector vaccine types had comparable immunogenicity when employed as boosters, both significantly higher than the inactivated virus vaccine, with no significant disparity regarding the vaccine brands. Patients with poor response to standard vaccination had a significant response to booster dose, with dialysis patients having stronger response. The differential effects of vaccine types and brands in the poor responders was similar to that of the overall RRT population. No rejection episodes or graft failure post-booster vaccination was reported.

CONCLUSION

In patients under RRT, booster dose vaccination against SARS-CoV-2 is safe and efficacious determined by significant seroconversion, and therefore, it should be considered to be implemented in all these patients. Since in the KTR patients, the third dose vaccination significantly increased the seroconversion rates even beyond that of the standard protocol, three dose vaccine doses is recommended to be recognized as the standard vaccination protocol in this population. The same recommendation could be considered for dialysis patients, due to their augmented risk of breakthrough infection.

Immunity in SARS-CoV-2 Infection: Clarity or Mystery? A Broader Perspective in the Third Year of a Worldwide Pandemic

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and its mechanisms have been thoroughly studied by researchers all over the world with the hope of finding answers that may aid the discovery of new treatment options or effective means of prevention. Still, over 2 years into the pandemic that is an immense burden on health care and economic systems, there seem to be more questions than answers. The character and multitude of immune responses elicited in coronavirus disease 2019 (COVID-19) vary from uncontrollable activation of the inflammatory system, causing extensive tissue damage and consequently leading to severe or even fatal disease, to mild or asymptomatic infections in the majority of patients, resulting in the unpredictability of the current pandemic. The aim of the study was to systematize the available data regarding the immune response to SARS-CoV-2, to provide some clarification among the abundance of the knowledge available. The review contains concise and current information on the most significant immune reactions to COVID-19, including components of both innate and adaptive immunity, with an additional focus on utilizing humoral and cellular responses as effective diagnostic tools. Moreover, the authors discussed the present state of knowledge on SARS-CoV-2 vaccines and their efficacy in cases of immunodeficiency.

Subunit microparticulate vaccine delivery using microneedles trigger significant SARS-spike-specific humoral and cellular responses in a preclinical murine model

The objective of this "proof-of-concept" study was to evaluate the synergistic effect of a subunit microparticulate vaccine and microneedles (MN) assisted vaccine delivery system against a human coronavirus. Here, we formulated PLGA polymeric microparticles (MPs) encapsulating spike glycoprotein (GP) of SARS-CoV as the model antigen. Similarly, we formulated adjuvant MPs encapsulating Alhydrogel® and AddaVax™. The antigen/adjuvant MPs were characterized and tested in vitro for immunogenicity. We found that the antigen/adjuvant MPs were non-cytotoxic in vitro. The spike GP MPs + Alhydrogel® MPs + AddaVax™ MPs showed enhanced immunogenicity in vitro as confirmed through the release of nitrite, autophagy, and antigen presenting molecules with their co-stimulatory molecules. Next, we tested the in vivo efficacy of the spike GP MP vaccine with and without adjuvant MPs in mice vaccinated using MN. The spike GP MPs + Alhydrogel® MPs + AddaVax™ MPs induced heightened spike GP-specific IgG, IgG1 and IgG2a antibodies in mice. Also, spike GP MPs + Alhydrogel® MPs + AddaVax™ MPs enhanced expression of CD4+ and CD8+ T cells in secondary lymphoid organ like spleen. These results indicated spike GP-specific humoral immunity and cellular immunity in vivo. Thus, we employed the benefits of both the subunit vaccine MPs and dissolving MN to form a non-invasive and effective vaccination strategy against human coronaviruses.

Japanese encephalitis virus induces vasodilation and severe lethality in adult and aged AG129 mice lacking alpha, beta and gamma interferon receptors

Japanese encephalitis virus (JEV) is a single-stranded positive-sense RNA virus belonging to the Flaviviridae family. The JEV is the leading cause of viral encephalitis in children and the elderly which is spread by mosquitoes. JEV infection has been established in different animal models such as mouse, hamster, guinea pig, swine, rat, monkey, rabbit by using the different routes of inoculations. Here, we have shown that the alpha/beta and gamma -receptor deficient AG129 mouse induces fatal encephalitis in both young and aged old mice, when challenged with high titer JEV Indian clinical isolate by both intraperitoneal and intradermal route. The JEV infected AG129 mouse have shown neurological symptoms, JEV-induced pathological features and supported high level viral replication. Additionally, administration of JEV in AG129 mice resulted in the induction of severe peripheral vascular permeability, which is a major hall mark of Dengue infection but not shown in JEV. Taken together, our results demonstrate interferon α/β and γ receptors knock out AG129 mouse does not need adaptation of JEV clinical isolates and could be is a promising JEV challenge mouse model by mimicking the natural intradermal route of administration for rapid screening of novel antivirals and vaccines.

The significance of thermomechanical processing on the cellular response of biomedical Co-Cr-Mo alloys

Strengthening of biomedical Co-Cr-Mo alloys has been explored via thermomechanical processing for enhancing the durability of their biomedical applications. However, the effects of cold and hot deformation on the cellular activity continue to be unclear. In this study, we prepared Co-Cr-Mo alloy rods via cold swaging and hot-caliber rolling and studied the relationship between the microstructure and cellular response of pre-osteoblasts. The cold-swaged rod experienced strain-induced martensitic transformation, which increased the volume fraction of the hexagonal close-packed (hcp) ε-martensite to ∼60 vol.% with an increase in area reduction (r) to 30%. The 111_γ fiber texture of the face-centered cubic (fcc) γ-matrix followed the Shoji-Nishiyama orientation relationship with ε-martensite. Cell culture results revealed beneficial effects of cold swaging on the cell response, in terms of adhesion, proliferation and morphology of cells, although increasing r did not significantly affect cellular metabolism levels. The addition of small content of Zr (0.04 wt.%) led to enhanced focal adhesion of cells, which became more significant at higher r. The microstructural evolution during hot-caliber rolling, namely, grain refinement without any phase transformation and strong texture development, did not appreciably affect the cellular activity. These findings are envisaged to facilitate alloy design and microstructural optimization for favorable tuning the osseointegration of biomedical Co-Cr-Mo alloys.

Responses of reconstituted human bronchial epithelia from normal and health-compromised donors to non-volatile particulate matter emissions from an aircraft turbofan engine

Health effects of particulate matter (PM) from aircraft engines have not been adequately studied since controlled laboratory studies reflecting realistic conditions regarding aerosols, target tissue, particle exposure and deposited particle dose are logistically challenging. Due to the important contributions of aircraft engine emissions to air pollution, we employed a unique experimental setup to deposit exhaust particles directly from an aircraft engine onto reconstituted human bronchial epithelia (HBE) at air-liquid interface under conditions similar to in vivo airways to mimic realistic human exposure. The toxicity of non-volatile PM (nvPM) from a CFM56-7B26 aircraft engine was evaluated under realistic engine conditions by sampling and exposing HBE derived from donors of normal and compromised health status to exhaust for 1 h followed by biomarker analysis 24 h post exposure. Particle deposition varied depending on the engine thrust levels with 85% thrust producing the highest nvPM mass and number emissions with estimated surface deposition of 3.17 × 10⁹ particles cm^-2 or 337.1 ng cm^-2. Transient increase in cytotoxicity was observed after exposure to nvPM in epithelia derived from a normal donor as well as a decrease in the secretion of interleukin 6 and monocyte chemotactic protein 1. Non-replicated multiple exposures of epithelia derived from a normal donor to nvPM primarily led to a pro-inflammatory response, while both cytotoxicity and oxidative stress induction remained unaffected. This raises concerns for the long-term implications of aircraft nvPM for human pulmonary health, especially in occupational settings.

COVID-19 mRNA Vaccine in Patients With Lymphoid Malignancy or Anti-CD20 Antibody Therapy: A Systematic Review and Meta-Analysis

BACKGROUND

The humoral response to vaccination in individuals with lymphoid malignancies or those undergoing anti-CD20 antibody therapy is impaired, but details of the response to mRNA vaccines to protect against COVID-19 remain unclear. This systematic review and meta-analysis aimed to characterize the response to COVID-19 mRNA vaccines in patients with lymphoid malignancies or those undergoing anti-CD20 antibody therapy.

MATERIALS AND METHODS

A literature search retrieved 52 relevant articles, and random-effect models were used to analyze humoral and cellular responses.

RESULTS

Lymphoid malignancies and anti-CD20 antibody therapy for non-malignancies were significantly associated with lower seropositivity rates (risk ratio 0.60 [95% CI 0.53-0.69]; risk ratio 0.45 [95% CI 0.39-0.52], respectively). Some subtypes (chronic lymphocytic leukemia, treatment-naïve chronic lymphocytic leukemia, myeloma, and non-Hodgkin's lymphoma) exhibited impaired humoral response. Anti-CD20 antibody therapy within 6 months of vaccination decreased humoral response; moreover, therapy > 12 months before vaccination still impaired the humoral response. However, anti-CD20 antibody therapy in non-malignant patients did not attenuate T cell responses.

CONCLUSION

These data suggest that patients with lymphoid malignancies or those undergoing anti-CD20 antibody therapy experience an impaired humoral response, but cellular response can be detected independent of anti-CD20 antibody therapy. Studies with long-term follow-up of vaccine effectiveness are warranted (PROSPERO registration number: CRD42021265780).

Pre-existing T cell immunity determines the frequency and magnitude of cellular immune response to two doses of mRNA vaccine against SARS-CoV-2

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Lack of CD4 T-cell response to first/second dose of mRNA vaccine was observed in 21% and 12% of health care workers (HCWs).

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T-cell response was greater in frequency/magnitude in HCWs with pre-existing immunity, due due to infection or cross-reactivity.

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Pre-existing immunity correlated with the magnitude of specific antibodies production after vaccination.

Little is known about the factors associated with lack of T-cell response to mRNA vaccines against SARS-CoV-2. In a prospective cohort of 61 health care workers (HCWs), 21% and 16% after the first dose of mRNA BNT162b vaccine, and 12% and 7% after the second dose, showed lack of CD4⁺ and CD8⁺ T-cell response, respectively. Pre-existing T-cell immunity, due to past infection (46%) or cross-reactive cellular response (26%), was significantly associated with T-cell response in frequency (CD4+ T-cell, 100% vs 82% after two doses; p = 0.049) and in the magnitude of T-cell response during follow up. Furthermore, baseline CD4⁺ T-cell correlated positively with the titer of specific IgG-antibodies after first and second vaccine dose. Our data demonstrate that cross-reactive T-cells correlate with a better cellular response as well as an enhanced humoral response, and we confirm the close correlation of humoral and cellular response after mRNA vaccination.

Joint effects and mechanisms of luteolin and kaempferol on toxigenic Microcystis growth-Comprehensive analysis on two isomers interaction in binary mixture

Allelochemicals are widely accepted as promising algaecide to mitigate Microcystis-dominated cyanobacterial blooms (MCBs). Allelopathic algicidal effect of single luteolin or kaempferol against Microcystis had been confirmed, but their joint effect against Microcystis was unclear. This study comprehensively explored time-dependent joint effect and mechanisms of luteolin and kaempferol on Microcystis growth during 14 day-test. The 50%-inhibitory threshold of their mixture (IC_{50 mix}) was verified as 4.872 and 5.211 mg/L at equitoxic ratio, and 5.167 and 4.487 mg/L at equivalent ratio, respectively, on day 8 and 14. Using toxicity unit, isobologram and predictive models, results revealed that luteolin and kaempferol at equivalent ratio interacted additively at lower, median and higher dosages, while at equitoxic ratio interacted additively at lower dosage but synergistically at median and higher dosages in Microcystis on day 8 and 14, implying that their equitoxic mixture posed better algicidal effect against Microcystis. Various dosages of equitoxic mixture concurrently decreased aqueous and total microcystins (MCs) contents along test. Thus, luteolin and kaempferol could be jointly applied as high-efficacy and eco-safe algaecide with declined MCs pollution risks. As mixture dosage elevated, more strongly weakened cellular MCs retention and inhibited cellular photosynthetic pigments content during late stage, as well as decreased aqueous MCs content long test, jointly explained increasing growth inhibition ratio with rising mixture dosage. Yet, cell damage was gradually repaired due to early stimulated antioxidant defense at each mixture dosage, thus cell damage might not be a major reason for inhibited growth under mixture stress. This study provided novel insights and guidance to coupled application of luteolin and kamepferol for mitigating MCBs and decreasing MCs pollution risks.

Limited T cell response to SARS-CoV-2 mRNA vaccine among patients with cancer receiving different cancer treatments

INTRODUCTION

Patients with cancer (PC) are at high risk of acquiring COVID-19 and can develop more serious complications. Deeper understanding of vaccines immunogenicity in this population is crucial for adequately planning vaccines programs. The ONCOVac study aimed to comprehensively assess the immunogenicity of mRNA-1273 vaccine in terms of humoral and cellular response.

METHODS

We conducted a prospective, single-center study including patients with solid tumours treated with cyclin-dependent kinases 4 and 6 inhibitors (CDK4/6i), immunotherapy (IT) or chemotherapy (CT). Patients were enrolled previously to vaccination with mRNA-1273. We also involved health care workers (HCW) to serve as a control group. We took blood samples before first dose administration (BL), after first dose (1D), and after second dose (2D). The primary objective was to compare the rate and magnitude of T cell response after second dose whereas safety and humoral response were defined as secondary objectives. We also collected patient reported outcomes after both the first and second vaccine dose and a six-month follow-up period to diagnose incident COVID-19 cases was planned.

RESULTS

The rate of specific anti-S serologic positivity (anti-S IgG cut-off point at 7,14 BAU/mL) was significantly higher in HCW compared to PC after 1D (100% versus 83.8%; p = 0.04), but similar after 2D (100% versus 95.8%; p = 0.5). This difference after 1D was driven by PC treated with CT (100% versus 64.5%; p = 0.001). Cellular response after 2D was significantly lower in PC than in HCW for both CD4+ (91.7% versus 59.7%; p = 0.001) and CD8+ (94.4% versus 55.6%; p < 0.001) T cells. We found a difference on pre-existing CD4+ T cell response in HCW comparing to PC (36% and 17%, p = 0.03); without difference in pre-existing CD8+ T cell response (31% and 23%, p = 0.5). After excluding patients with pre-existing T cell response, PC achieved even lower CD4+ (50.9% versus 95.5%, p < 0.001) and CD8+ (45.5% versus 95.5%, p < 0.001) T cell response compared with HCW. Regarding safety, PC reported notably more adverse events than HCW (96.6% versus 69.2%, p < 0.001).

CONCLUSION

We demonstrated that PC showed a similar humoral response but a lower T cell response following two doses of mRNA-1273 vaccination. Further studies are needed to complement our results and determine the implication of low T cell response on clinical protection of PC against COVID-19.

In situ polymerization of conducting polymers around living neural cells: Cellular effect study

Conducting polymer has been directly polymerized around living neural cells or in the cortex with the aim of creating an intimate contact between implantable electrical devices and electrogenetic cells. The long term cellular effect after conductive polymer coating, a critical issue for practical applications, has not been reported. In this study, poly(3,4-ethylenedioxythiophene) PEDOT was directly polymerized around the living primary neural and PC12 cells under varying current densities, potentials and charge-balanced current pulses. The cell morphology, nuclei evolution, and cell viability post PEDOT polymerization were studied at different time points. The aim of this study was to investigate the immediate and long-term cellular response towards in-situ polymerization of conductive polymers and to provide experimental information on the feasibility of this technique in practical applications.

Local immune response of Canarian Majorera goats infected with Teladorsagia circumcincta

BACKGROUND

Due to increased anthelmintic resistance, alternative methods to drugs are necessary to control gastrointestinal nematodes (GINs). Some of the most promising alternatives are based on the immune response of the host, such as the selection of genetically resistant breeds or the use of vaccines against these parasites. Given the limited information available on the immune response against GINs in goats, this study investigated the local immune response of goat kids of an indigenous Canary Islands breed (Majorera breed) experimentally infected with Teladorsagia circumcincta, one of the most pathogenic and prevalent GIN species.

METHODS

For this purpose, the relationship between different parasitological (number of mature and immature worms, worm length, and number of intrauterine eggs) and immunological parameters at the local level (related to both the humoral and cellular immune response) was analyzed at early (1 week post-infection [wpi]) and late (8 wpi) stages of infection.

RESULTS

Primary infection of goat kids with T. circumcincta infective larvae (L3) generated a complex immune response that could be defined as Th2 type, characterized by increased infiltration in abomasal tissues of several effector cells as well as a progressive presence of specific antibodies against parasitic antigens in the gastric mucus. Cellular responses were evidenced from 1 wpi onward, showing an increase in antigen-presenting cells and various lymphocyte subsets in the gastric mucosa.

CONCLUSIONS

The complexity of the host response was evidenced by statistically significant changes in the number of all these subpopulations (MHCII⁺, CD4⁺, CD8⁺, γδ⁺, CD45R⁺, IgA⁺, and IgG⁺), as well as in the evolution of the relative cytokine gene expression. From a functional point of view, negative associations were observed between the number of most of the immune cells (CD4, IgA, IgG, and CD45R cells) and parameters that could be related to the fecundity of worms, a phenomenon that was especially evident when the number of IgG and CD45R cells or the specific IgA levels of the gastric mucus were compared with parasitological parameters such as the female worm length or fecal egg counts at 8 wpi.

'Cookies on a tray': Superselective hierarchical microstructured poly(l-lactide) surface as a decoy for cells

In this research we developed a micro-sized hierarchical structures on a poly(l-lactide) (PLLA) surface. The obtained structures consist of round-shaped protrusions with a diameter of ~20 μm, a height of ~3 μm, and the distance between them ~30 μm. We explored the effect of structuring PLLA to design a non-cytotoxic material with increased roughness to encourage cells to settle on the surface. The PLLA films were prepared using the casting melt extrusion technique and were modified using ultra-short pulse irradiation - a femtosecond laser operating at λ = 1030 nm. A hierarchical microstructure was obtained resembling 'cookies on a tray'. The cellular response of fibro- and osteoblasts cell lines was investigated. The conducted research has shown that the laser-modified surface is more conducive to cell adhesion and growth (compared to unmodified surface) to such an extent that allows the formation of highly-selectively patterns consisting of living cells. In contrast to eukaryotic cells, the pathogenic bacteria Staphylococcus aureus covered modified and unmodified structures in an even, non-preferential manner. In turn, adhesion pattern of eukaryotic fungus Saccharomyces boulardii resembled that of fibro- and osteoblast cells rather than that of Staphylococcus. The discovered effect can be used for fabrication of personalized and smart implants in regenerative medicine.

Tailoring the biofunctionality of collagen biomaterials via tropoelastin incorporation and EDC-crosslinking

Recreating the cell niche of virtually all tissues requires composite materials fabricated from multiple extracellular matrix (ECM) macromolecules. Due to their wide tissue distribution, physical attributes and purity, collagen, and more recently, tropoelastin, represent two appealing ECM components for biomaterials development. Here we blend tropoelastin and collagen, harnessing the cell-modulatory properties of each biomolecule. Tropoelastin was stably co-blended into collagen biomaterials and was retained after EDC-crosslinking. We found that human dermal fibroblasts (HDF), rat glial cells (Rugli) and HT1080 fibrosarcoma cells ligate to tropoelastin via EDTA-sensitive and EDTA-insensitive receptors or do not ligate with tropoelastin, respectively. These differing elastin-binding properties allowed us to probe the cellular response to the tropoelastin-collagen composites assigning specific bioactivity to the collagen and tropoelastin component of the composite material. Tropoelastin addition to collagen increased total Rugli cell adhesion, spreading and proliferation. This persisted with EDC-crosslinking of the tropoelastin-collagen composite. Tropoelastin addition did not affect total HDF and HT1080 cell adhesion; however, it increased the contribution of cation-independent adhesion, without affecting the cell morphology or, for HT1080 cells, proliferation. Instead, EDC-crosslinking dictated the HDF and HT1080 cellular response. These data show that a tropoelastin component dominates the response of cells that possess non-integrin based tropoelastin receptors. EDC modification of the collagen component directs cell function when non-integrin tropoelastin receptors are not crucial for cell activity. Using this approach, we have assigned the biological contribution of each component of tropoelastin-collagen composites, allowing informed biomaterial design for directed cell function via more physiologically relevant mechanisms. STATEMENT OF SIGNIFICANCE: Biomaterials fabricated from multiple extracellular matrix (ECM) macromolecules are required to fully recreate the native tissue niche where each ECM macromolecule engages with a specific repertoire of cell-surface receptors. Here we investigate combining tropoelastin with collagen as they interact with cells via different receptors. We identified specific cell lines, which associate with tropoelastin via distinct classes of cell-surface receptor. These showed that tropoelastin, when combined with collagen, altered the cell behaviour in a receptor-usage dependent manner. Integrin-mediated tropoelastin interactions influenced cell proliferation and non-integrin receptors influenced cell spreading and proliferation. These data shed light on the interplay between biomaterial macromolecular composition, cell surface receptors and cell behaviour, advancing bespoke materials design and providing functionality to specific cell populations.

Cellular Markers of Immunosuppression in Sepsis

Sepsis is a pathological condition frequently caused by invasion of a pathogen and the subsequent unregulated response that threatens the patient's life through diverse organ failure. The incidence of sepsis is increasing, and there is no specific therapy. Despite technological contributions to treat sepsis or increased knowledge of its molecular pathophysiology, mortality remains high, and sepsis is a global health problem. Knowledge of the role of the cells involved in the host response through the synthesis of inflammatory mediators and their different effects on cells, tissues or systems is key to the development of medical treatments that regulate systems involved in such responses to pathogens. This review addresses new insights into the role of cells, their mediators, and the interaction between them that lead to the development of a state of immunosuppression.

Humoral and cellular response to SARS-CoV-2 BNT162b2 mRNA vaccine in hemodialysis patients

Background

Hemodialysis (HD) patients have an increased risk of acquiring infections due to many health care contacts and may, in addition, have a suboptimal response to vaccination and a high mortality from Covid-19 infection.

Methods

In 50 HD patients (mean age 69.4 years, 62% men) administration of SARS-CoV-2BNT162b2 mRNA vaccine began in Dec 2020 and the immune response was evaluated 7–15 weeks after the last dose. Levels of Covid-19 (SARS-CoV-2) IgG antibody against the nucleocapsid antigen (anti-N) and the Spike antigen (anti-S) and T-cell reactivity testing against the Spike protein using ELISPOT technology were evaluated.

Results

Out of 50 patients, anti-S IgG antibodies indicating a vaccine effect or previous Covid-19 infection, were detected in 37 (74%), 5 (10%) had a borderline response and 8 (16%) were negative after two doses of vaccine. T-cell responses were detected in 29 (58%). Of the 37 patients with anti-S antibodies, 25 (68%) had a measurable T-cell response. 2 (40%) out of 5 patients with borderline anti-S and 2 (25%) without anti-S had a concomitant T-cell response. Twenty-seven (54%) had both an antibody and T-cell response. IgG antibodies to anti-N indicating a previous Covid-19 disease were detected in 7 (14%) patients.

Conclusions

Most HD patients develop a B- and/or T-cell response after vaccination against Covid-19 but approx. 20% had a limited immunological response. T-cell reactivity against Covid-19 was only present in a few of the anti-S antibody negative patients.

Evaluation of cellular response and drug delivery efficacy of nanoporous stainless steel material

OBJECTIVE

Various surface modification techniques that can further improve the function and usability of stainless steel as a medical device have been reported. In the present study, the physical and biological properties of nanoporous stainless steel as well as its usefulness for drug delivery were assessed.

METHODS

The specimen was prepared with a circular disk shape (15 mm in diameter and 1 mm in thickness). The disk was subjected to electropolishing at a constant voltage of 20 V and 10 A for 10 min in an acidic environment (50% H₂SO₄). Everolimus (EVL) was used as a testing drug for drug-loading capacity of the material surface and release kinetics. The physiobiological properties of the material were assessed using platelet adhesion, and smooth muscle cell (SMC) adhesion, migration, and proliferation assays.

RESULTS

The surface roughness of the postpolishing group was greater than that of the nonpolishing group. Platelet adhesion and SMC adhesion and migration were inhibited in the postpolishing group compared to those in the prepolishing group. In the postpolishing group, the total amount of EVL on the surface (i.e., drug storage rate) was higher and the drug release rate was lower, with half the amount of the EVL released within 4 days compared with only 1 day for that of the prepolishing group.

CONCLUSION

Taken together, this stainless steel with a nanoporous surface could be used as a medical device for controlling cellular responses and carrying drugs.

A possible role of tachykinin-related peptide on an immune system activity of mealworm beetle, Tenebrio molitor L

Tachykinin-related peptides (TRPs) are important neuropeptides. Here we show that they affect the insect immune system, especially the cellular response. We also identify and predict the sequence and structure of the tachykinin-related peptide receptor (TRPR) and confirm the presence of expression of gene encoding TRPR on Tenebrio molitor haemocytes. After application of the Tenmo-TRP-7 in T. molitor the number of circulating haemocytes increased and the number of haemocytes participating in phagocytosis of latex beads decreased in a dose- and time-dependent fashion. Also, Tenmo-TRP-7 affects the adhesion ability of haemocytes. Six hours after injection of Tenmo-TRP-7, a decrease of haemocyte surface area was observed under both tested Tenmo-TRP-7 concentrations (10^-7 and 10^-5 M). The opposite effect was reported 24 h after injection, which indicates that the influence of Tenmo-TRP-7 on modulation of haemocyte behaviour differs at different stages of stress response. Tenmo-TRP-7 application also resulted in increased phenoloxidase activity 6 and 24 h after injection. The assessment of DNA integrity of haemocytes showed that the injection of Tenmo-TRP-7 at 10^-7 M led to a decrease in DNA damage compared to control individuals. This effect was only visible 6 h after Tenmo-TRP-7 application. After 24 h, Tenmo-TRP-7 injection increased DNA damage. We also confirmed the expression of immune-related genes in nervous tissue of T. molitor. Transcripts for genes encoding receptors participating in pathogen recognition processes and antimicrobial peptides were detected in T. molitor brain, retrocerebral complex and ventral nerve cord. These results may indicate a role of the insect nervous system in pathogen recognition and modulation of immune response similar to vertebrates. Taken together, our results support the notion that tachykinin-related peptides probably play an important role in the regulation of the insect immune system. Moreover, some resemblances with action of tachykinin-related peptides and substance P showed that insects can be potential model organisms for analysis of hormonal regulation of conserved innate immune mechanisms.

Cellular and humoral immune responses associated with protection in sheep vaccinated against Teladorsagia circumcincta

Due to increased anthelmintic resistance, complementary methods to drugs are necessary to control gastrointestinal nematodes (GIN). Vaccines are an environmentally-friendly and promising option. In a previous study, a Teladorsagia circumcincta recombinant sub-unit vaccine was administered to two sheep breeds with different levels of resistance against GIN. In the susceptible Canaria Sheep (CS) breed, vaccinates harboured smaller worms with fewer eggs in utero than the control group. Here, we extend this work, by investigating the cellular and humoral immune responses of these two sheep breeds following vaccination and experimental infection with T. circumcincta. In the vaccinated CS group, negative associations between antigen-specific IgA, IgG₂ and Globule Leukocytes (GLs) with several parasitological parameters were established as well as a higher CD4⁺/CD8⁺ ratio than in control CS animals, suggesting a key role in the protection induced by the vaccine. In the more resistant Canaria Hair Breed (CHB) sheep the vaccine did not significantly impact on the parasitological parameters studied and none of these humoral associations were observed in vaccinated CHB lambs, although CHB had higher proportions of CD4⁺ and CD8⁺ T cells within the abomasal lymph nodes, suggesting higher mucosal T cell activation. Each of the component proteins in the vaccine induced an increase in immunoglobulin levels in vaccinated groups of each breed. However, levels of immunoglobulins to only three of the antigens (Tci-MEP-1, Tci-SAA-1, Tci-ASP-1) were negatively correlated with parasitological parameters in the CS breed and they may be, at least partially, responsible for the protective effect of the vaccine in this breed. These data could be useful for improving the current vaccine prototype.

Inactivation of Aspergillus species in real water matrices using medium pressure mercury lamps

The aim of this work is to understand the inactivation efficiency of medium pressure mercury lamps, measured in terms of growth inhibition as well as cell death, damage and response, using three strains from three different Aspergillus species (A. fumigatus, A. niger and, A. terreus) spiked in filtered surface water. A complete characterization of the effect of the treatment on each strain of the fungal species was assessed considering spores' morphology, cell wall integrity and enzymatic activity, the formation of pyrimidine dimers in the DNA and proteome analysis. Results showed that, when subjected to medium pressure mercury lamps, A. niger is the most resistant to inactivation, that both A. fumigatus and A. niger suffer more morphological changes and present a higher number of damaged spores and A. terreus presented more dead spores. DNA damages detected in A. niger were able to be repaired to some extent, under both light and dark conditions. Finally, proteome analysis showed that the UV radiation treatment triggered different types of stress response, including cell wall reorganization and DNA repair in A. fumigatus and A. terreus, and oxidative stress responses like the increase in production of citric acid and itaconic acid in A. niger and A. terreus, respectively.

Survival and gene expression responses in immune challenged larval lake sturgeon

Larval lake sturgeon, Acipenser fulvescens, reared in hatcheries for stock enhancement of wild populations may be susceptible to early opportunistic bacterial infection. Thus, we examined survival and whole-body mRNA expression of both stress- and immune-related genes (MyD88, IL-1β, StAR, GR1, and HSP70) in 30 days post fertilization larval lake sturgeon following immune challenge with lipopolysaccharides (LPS). Larval sturgeon were exposed to 0, 25, 50, 100, 150, and 200 μg ml^-1 LPS and sampled after 30 min, 4 h, and 48 h. Mortality was zero in 0 and 25 μg ml^-1 LPS; 37.5% in 50 μg ml^-1 LPS and 100% in the higher concentrations. Expression of MyD88 and StAR mRNA were positively correlated and increased with time in the 50 μg ml^-1 LPS treatment. There was an influence of both treatment and time on IL-1β mRNA, with expression 10-fold higher than controls after 4 h. Expression of HSP70 mRNA was suppressed within 30 min of 50 μg ml^-1 LPS exposure and remained so throughout the time course. Correlated mRNA expression of GR1 with MyD88, StAR and IL-1β suggests a potential relationship between the innate immune and glucocorticoid responses of larval lake sturgeon during this early developmental stage. Data presented suggest that larval lake sturgeon largely responded with predicted changes in gene expression of immune related and stress response genes following LPS challenge. This study provides a foundation for future research examining the effects of hatchery and naturally occurring stressors on the immune responses of larval lake sturgeon.

MicroRNA: a novel implication for damage and protection against ionizing radiation

Ionizing radiation (IR) is a form of high energy. It poses a serious threat to organisms, but radiotherapy is a key therapeutic strategy for various cancers. It is significant to reduce radiation injury but maximize the effect of radiotherapy. MicroRNAs (miRNAs) are posttranscriptionally regulatory factors involved in cellular radioresponse. In this review, we show how miRNAs regulate important genes on cellular response to IR-induced damage and how miRNAs participate in IR-induced carcinogenesis. Additionally, we summarize the experimental and clinical evidence for miRNA involvement in radiotherapy and discuss their potential for improvement of radiotherapy. Finally, we highlight the role that miRNAs play in accident exposure to IR or radiotherapy as predictive biomarker. miRNA therapeutics have shown great perspective in radiobiology; miRNA may become a novel strategy for damage and protection against IR.

[Chronic toxicity of Multi-walled carbon nanotubes in human pleural mesothelial cells]

Objective: To explore the chronic toxicity and its potential mechanism of multi-walled carbon nanotube (MWCNT) in human pleural mesothelial cells. Methods: A sustainable exposure of MeT-5A cells to MWCNT at 10 μg/cm(2) for one year was conducted in 2016. During the exposure, the cell images and cell proliferation was recorded every 4 weeks. The cell apoptosis, cell cycle, cell migration and cell invasion were compared between the control cells and the cells after MWCNT exposure. Finally, the gene expression was screened with Affymetrix clariom D assay, and some of the significantly differential expressed genes was verified by RT-PCR. Results: Compared with the control group, the proliferation ability of the cells in the 1-year exposed group was significantly increased, and the rate of proliferation was about 2-3 times as that in the Control Group (F=481.32, P<0.05) . MeT-5A cells all showed cell cycle arrest effect, which showed the increase of G1 phase and the decrease of s phase and G2 phase (F=14.94, P<0.05) . The apoptosis rate of cells in the treated group was significantly higher than that in the control group after 6 months (F=15.12, P<0.05) , but the early apoptosis rate and the total apoptosis rate of cells in the treated group were not significantly different from those in the control group after 1 year (F=3.97, P<0.05) . The cell migration and invasion were both promoted by MWCNT. Furthermore, the differentially expressed genes was screened, to find 2, 878 genes with more than 2 folds changes. To further verified, RT-PCR was conducted with PIK3R3、WNT2B、VANGL2、ANXA1, and their expression changes were consistent with above. Conclusion: MWCNT might have a carcinogenic potential to MeT-5A cells after the long term exposure.

Label-free screening of biochemical changes in macrophage-like cells following MoS2 exposure using Raman micro-spectroscopy

The emergence of large scale production techniques for 2D particulate materials has dramatically increased their applications potential. Understanding the interactions of biological cells with such particulate material is therefore of paramount importance, both for toxicological assessment and potential biomedical applications. Conventional in-vitro cytological assays commonly record only a single colorimetric end-point, and do not provide an in-depth analysis of how such materials are uptaken and processed within cells. To demonstrate its potential as an alternative, label free approach, confocal Raman micro-spectroscopy has been used to profile the cellular response of macrophage-like immune cells as a result of exposure to a sub-lethal dose of particulate MoS₂, as an example novel 2D material. Particles were seen to be uptaken and trafficked in sub-cellular vesicles, and this sensitive technique allows differences in the biochemical composition of the vesicles to be assessed and monitored as a function of time. Untreated macrophage-like cells contain lipidic vesicles which are found to be relatively rich in the membrane lipid sphingomyelin, key to the process of cell membrane regeneration. After exposure to MoS₂, the particulate material is seen to be invaginated in similar vesicles, the most prominent of which now, however, have spectroscopic signatures which are dominated by those of phosphatidyl family lipids, consistent with the phagocytotic pathway. The lipidic content of cells is seen to increase at all time-points (4, 24 and 72 h). although vesicles composed of sphingomyelin become more prominent again following a prolonged incubation of 72 h to a sub-lethal dose of MoS₂, as the immune cell has processed the particulate material and initiates recovery to a normal/untreated state. This study reveals Raman micro-spectroscopy is an effective method for monitoring cellular responses and evolution of organelle compositions in response to MoS₂ exposure. The additional benefit of using this technique is that cells can be monitored as a function of time, while it can also be used for screening other micro/nano materials for toxicology and/or establishing cell responses.

CD73 and cN-II regulate the cellular response to chemotherapeutic and hypoxic stress in lung adenocarcinoma cells

BACKGROUND

Cytosolic 5'-nucleotidase II (cN-II) and ecto-5'-nucleotidase (CD73) are enzymes involved in the nucleotide metabolism by dephosphorylating nucleoside monophosphates. Both enzymes are involved in cancer by modifying anticancer drug activity, cancer cell biology and immune modulation.

METHODS

We have modified lung cancer cells (NCI-H292) to become deficient for either or both enzymes using the CRISPR/Cas9 technique, and studied the implication of the two enzymes in the cellular response to different stress condition i.e. chemotherapeutic agents, hypoxia and nucleotide stress.

RESULTS

Our results show that there is no significant role of these enzymes in cell proliferation under hypoxic stress. Similarly, cN-II and CD73 are not involved in wound healing ability under CoCl₂-mediated HIF-1α stabilization. Furthermore, our results show that CD73-deficiency is associated with increased apoptosis in response to 1600 μM adenosine, decreased sensitivity to mitomycin and enhanced sensitivity to vincristine. cN-II deficiency increased in vivo tumor growth and sensitivity to vincristine and mitomycin C.

CONCLUSIONS

Our study gives new insights into the biological roles of cN-II and CD73 under stress conditions in this particular cancer cell line. Further experiments will help deciphering the molecular mechanisms underlying the observed differences.

Vaccine Delivery and Immune Response Basics

In this opening chapter, we outline the basics of vaccine delivery and subsequent immune reactivity. Vaccine delivery is an augmentation to immunization more generally in that a delivery reagent is harnessed to improve administration of the key ingredient (i.e., the antigen) needed to provoke an immune response. In this chapter, we discuss the evolution of vaccine design and how such efforts evolved into targeted administration/delivery of key antigens. We then provide overview descriptions of vaccine immune responses and methods for assessment. More generally, the chapter sets the tone for the remainder of this book, which will focus upon each step of the vaccine process with a special emphasis on how vaccine delivery contributes to overall health outcomes.

Multiple modes of cell death in neuroendocrine tumors induced by artesunate

BACKGROUND

The paucity of effective treatment in neuroendocrine tumors (NETs) encouraged us to investigate the therapeutic value of artesunate (ART) promised by its inhibitory effect against various tumors and broad safety profile.

METHODS

We evaluated the impact of ART on three NET cell lines, BON-1, QGP-1 and NCI-H727 on cellular and molecular levels.

RESULTS

Our results showed that ART induced endoplasmic reticulum (ER) stress through phosphorylation of eIF2α, which further gave rise to autophagy in all three NET cell lines. Specifically, apoptosis and ferroptosis were also observed in BON-1 cells, which made BON-1 cell line more vulnerable upon ART treatment. The different sensitivities presented on the three cell lines also associated with a differential regulation of p21 on the long run. Co-treatment with p21 inhibitor UC2288 showed an additive effect on QGP-1 and NCI-H727 cell lines indicating p21 upregulation in these two cell lines might confer resistance towards ART treatment.

CONCLUSIONS

It is possible to include ART in the treatment of NETs in the future.

Denatured corona proteins mediate the intracellular bioactivities of nanoparticles via the unfolded protein response

Biomolecular corona formed on nanoparticles (NPs) influences the latter's in vivo biological effects. Nanomaterials with different physicochemical properties exert similar adverse effects, such as cytotoxicity, suggesting the existence of ubiquitous signals during various corona formations that mediate common and fundamental cellular events. Here, we discover the involvement of the unfolded protein response (UPR) and recruited chaperones in the corona. Specially, heat shock protein 90 kDa α class B member 1 (Hsp90ab1) is abundantly enriched in the corona, accompanied by substantial aggregation of misfolded protein on particles intracellularly. Further analysis reveals the particulate matter 2.5 (PM2.5) and metal-containing particles are more capable of denaturing proteins. The recruited Hsp90ab1 activates diverse NPs' pathological behaviour by heat stress response (HSR), which were significantly reversed by geldanamycin (GA), the inhibitor of Hsp90ab1. Murine lung inflammation induced by PM2.5 and iron oxide NPs (Fe₃O₄NPs) is suppressed by GA, highlighting that Hsp90ab1-mediated UPR is a potential target for the treatment of environmental pollution-related illnesses. Based on our findings, the UPR and Hsp90ab1 presented in the corona of particles initiate fundamental intracellular reactions that lead to common pathological outcomes, which may provide new insights for understanding nanotoxicity and designing therapeutic approaches for diseases associated with environmental pollution.

Recruited CD68+CD206+ macrophages orchestrate graft immune tolerance to prompt xenogeneic-dentin matrix-based tooth root regeneration

Successful regenerative medicine strategies of xenogeneic extracellular matrix need a synergistic balance among inflammation, fibrosis, and remodeling process. Adaptive macrophage subsets have been identified to modulate inflammation and orchestrate the repair of neighboring parenchymal tissues. This study fabricated PPARγ-primed CD68⁺CD206⁺ M2 phenotype (M2γ), and firstly verified their anti-inflammatory and tissue-regenerating roles in xenogeneic bioengineered organ regeneration. Our results showed that Th1-type CD3⁺CD8⁺ T cell response to xenogeneic-dentin matrix-based bioengineered root complex (xeno-complex) was significantly inhibited by M2γ macrophage in vitro. PPARγ activation also timely recruited CD68⁺CD206⁺ tissue macrophage polarization to xeno-complex in vivo. These subsets alleviated proinflammatory cytokines (TNF-α, IFN-γ) at the inflammation site and decreased CD3⁺CD8⁺ T lymphocytes in the periphery system. When translated to an orthotopic nonhuman primate model, PPARγ-primed M2 macrophages immunosuppressed IL-1β, IL-6, TNF-α, MMPs to enable xeno-complex to effectively escape immune-mediated rejection and initiate graft-host synergistic integrity. These collective activities promoted the differentiation of odontoblast-like and periodontal-like cells to guide pulp-dentin and cementum-PDLs-bone regeneration and rescued partially injured odontogenesis such as DSPP and periostin expression. Finally, the regenerated root showed structure-biomechanical and functional equivalency to the native tooth. The timely conversion of M1-to-M2 macrophage mainly orchestrated odontogenesis, fibrogenesis, and osteogenesis, which represents a potential modulator for intact parenchymal-stromal tissue regeneration of targeted organs.

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Alternative polarized M2 macrophage could perform anti-inflammatory effects to inhibit xenogeneic host-to-graft rejection.

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A model of bioengineered tooth root regeneration was used to study parenchymal/hard and stromal/soft tissues regeneration.

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PPARγ-primed M2 macrophage orchestrated graft immune tolerance to prompt odontogenesis, fibrogenesis, and osteogenesis.

Night shift work and immune response to the meningococcal conjugate vaccine in healthy workers: a proof of concept study

BACKGROUND

It is well-established that sleep regulates immune functions. Immunological functions are dependent on circadian rhythms and regular sleep as both have an impact on the magnitude of immune responses following antigenic challenge (eg, in vaccination). Here we investigated whether nocturnal shift work can influence post-vaccination response.

METHODS

Thirty-four healthy workers (23 females) working either nocturnal or diurnal shifts (17 in each group) received the meningococcal C meningitis vaccine. Sleep was recorded polysomnographically (PSG) and with actigraphy. Humoral and cellular responses were assessed after vaccination.

RESULTS

Night workers showed decreased N3 stage and REM sleep duration, increased inflammatory mediators (TNF-α and IL-6 levels), and a weak specific humoral response to vaccination associated with reduced CD4 T lymphocytes, reduced plasmacytoid dendritic cells, reduced prolactin levels, increased T_Reg and increased IL-10 levels. In addition, the decrease in total sleep time and circadian rhythm alterations were associated with a reduced humoral response post-vaccination.

CONCLUSIONS

Our findings provide novel evidence concerning immune alterations of shift work on workers' health based on real-life circumstances. In association with circadian components, sufficient sleep time and rhythm synchronization were important for the development of the Ag-specific immune response, suggesting that the humoral response to vaccination may be impaired in individuals with chronic sleep restriction and circadian misalignment.

Growth and Cellular Responses of Toxigenic Microcystis to Chloramphenicol-Stress at Various Environmentally-Relevant Nitrogen Levels

This study explored nitrogen (N)-dependent interaction between Microcystis and chloramphenicol (CAP) along 20 day-test. Results showed that 5 mg/L N largely alleviated inhibitory effects of CAP on Microcystis growth, while 50 and 0.5 mg/L N exacerbated growth-inhibition by CAP especially in early (before day 8) and mid-late stage, respectively. At each N level, CAP-induced antioxidant defense and cell damage extents were negatively correlated to growth state in each stage, and CAP-biodegradation coincided with Microcystis growth and glutathione synthesis dynamics, implying that antioxidant defense, cell damage and CAP-removal closely linked to N-dependent Microcystis growth under CAP-stress. Microcystin (MC)-production and -release under CAP-stress were also N-dependent. Although Microcystis growth was greatly-inhibited by prolonged CAP-stress at 0.5 mg/L N, delayed CAP-loss and high MC-release at 0.5 mg/L N should be emphasized during Microcystis-dominated cyanobacterial blooms (MCBs) and CAP co-occurrence. This study had great implication in risk assessment for MCBs-CAP co-occurrence in different waters.

Antibacterial and cellular response of piezoelectric Na0.5K0.5NbO3modified 1393 bioactive glass

In the present study, the combined effect of addition of varying concentrations (10-30 vol%) of biocompatible piezoelectric Na_0.5K_0.5NbO₃ (NKN) as well as electrostatic and dynamic pulsed electrical treatment on antibacterial and cellular response of 1393 bioactive glass (1393 BG) has been examined. The phase analyses of the sintered (at 800 °C for 30 min) samples revealed the formation of 1393 BG - NKN composites without any appearance of secondary phases. The addition of 10-30 vol% NKN significantly improved the mechanical behaviour of 1393 BG like, hardness (1.7 to 2 times), fracture toughness (1.3 to 2.6 times), compressive (2.3 to 8 times) and flexural strengths (2 to 3.5 times) than monolithic 1393 BG. The piezoelectric NKN is observed to induce the antibacterial activity in 1393 BG - (10- 30 vol%) NKN composites, while Staphylococcus aureus (S. aureus, gram positive) and Escherichia coli (E. coli, gram negative) bacterial cells were exposed to unpolarized and polarized (20 kV, 500°C for 30 min) sample surfaces. The antibacterial response was examined using disc diffusion, nitro blue tetrazolium (NBT) and MTT assays. The statistical analyses revealed the significant reduction in the viability of bacterial cells on polarized 1393 BG - (10- 30 vol%) NKN composite samples. In addition, the combined effect of electrostatic and dynamic pulsed electrical stimulation (1 V/cm, 500 μs pulses) on the cellular response of 1393 BG and 1393 BG - 30 vol% NKN composites has been analysed with MG-63 osteoblast-like cells. The cell proliferation was observed to increase significantly for the dynamic pulsed electric field treated negatively charged surfaces.

Humoral and cellular immune response induced by rVSVΔG-ZEBOV-GP vaccine among frontline workers during the 2013-2016 West Africa Ebola outbreak in Guinea

BACKGROUND

As part of a Phase III trial with the Ebola vaccine rVSVΔG-ZEBOV-GP in Guinea, we invited frontline workers (FLWs) to participate in a sub-study to provide additional information on the immunogenicity of the vaccine.

METHODS

We conducted an open-label, non-randomized, single-arm immunogenicity evaluation of one dose of rVSVΔG-ZEBOV-GP among healthy FLWs in Guinea. FLWs who refused vaccination were offered to participate as a control group. We followed participants for 84 days with a subset followed-up for 180 days. The primary endpoint was immune response, as measured by ELISA for ZEBOV-glycoprotein-specific antibodies (ELISA-GP) at 28 days. We also conducted neutralization, whole virion ELISA and enzyme-linked immunospot (ELISPOT) assay for cellular response.

RESULTS

A total of 1172 participants received one dose of vaccine and were followed-up for 84 days, among them 114 participants were followed-up for 180 days. Additionally, 99 participants were included in the control group and followed up for 180 days. Overall, 86.4% (95% CI 84.1-88.4) of vaccinated participants seroresponded at 28 days post-vaccination (ELISA- GP) with 65% of these seroresponding at 14 days post-vaccination. Among those who seroresponded at 28 days, 90.7% (95% CI 82.0-95.4) were still seropositive at 180 days. The proportion of seropositivity in the unvaccinated group was 0.0% (95% CI 0.0-3.8) at 28 days and 5.4% (95% CI 2.1-13.1) at 180 days post-vaccination. We found weak correlation between ELISA-GP and neutralization at baseline but significant pairwise correlation at 28 days post-vaccination. Among samples analysed for cellular response, only 1 (2.2%) exhibited responses towards the Zaire Ebola glycoprotein (Ebola GP ≥ 10) at baseline, 10 (13.5%) at day 28 post-vaccination and 27 (48.2%) at Day 180.

CONCLUSIONS

We found one dose of rVSVΔG-ZEBOV-GP to be highly immunogenic at 28- and 180-days post vaccination among frontline workers in Guinea. We also found a cellular response that increased with time.

The cellular responses of autophagy, apoptosis, and 5-methylcytosine level in zebrafish cells upon nutrient deprivation stress

Here we reported the stress responses of nutrient deprivation and extended observation of autophagy, apoptosis, and DNA methylation in zebrafish embryonic fibroblast (ZF4) cells. Our results showed that serum deprivation resulted in the changes of cell shape and adherent ability, the suppressed cell growth and viability, and the inhibited proliferation and cell cycle. Besides, the appearance of lysosome and autophagosome/autolysosome with significantly increased expression of mRNAs (ulk1a, becn1, atg12, sqstm1, maplc3, and lamp1) and proteins (Atg12, Becn1, Sqstm1, and Lamp1) indicate the autophagic activity was boosted at initial stage but relatively weakened at 48 h of serum starvation. When autophagy no longer mitigate for the stress, cell apoptosis detected by the mRNA expression of caspases, Bcl-2/Bax expression, and Annexin V/PI was gradually enhanced to execute the death plan upon prolonged starvation process. Furthermore, the methyl group metabolism was increased in accordance with autophagic activity and was suppressed by enhanced apoptotic activity. These data suggested that the recycle activity induced by autophagy could compensate the substrates and reactions of DNA transmethylation, which obviously increased 5-methylcytosine (5 mC) level in ZF4 cells. In summary, our results discovered the cellular responses under prolonged serum starvation stress and elaborated the switch from autophagy to apoptosis and corresponding correlation with 5 mC level changes in teleost fish in vitro.

Expression analysis of the heat shock protein genes and cellular reaction in dojo loach (Misgurnus anguillicaudatus) under the different pathogenic invasion

As molecular chaperones, heat shock proteins (HSPs) play essential roles in cells in response to stress conditions. Recent studies about immune functions of HSPs in fish have also been reported. In this study, based on the reported cDNA sequences of the four HSP genes, HSP70, HSC70, HSP90α and HSP90β, the temporal expression patterns of the four genes during embryonic development of dojo loach(Misgurnus anguillicaudatus) was assayed with qRT-PCR. All of the four genes were ubiquitously expressed in all detected embryonic developmental stages. Among of them, HSP70, HSC70 and HSP90β were highly expressed in the organ formation stage, while HSP90α was the highest expressed in myotome formation stage. Further, the immune responses of the four HSP genes were assayed when loach were infected with three different pathogens, bacterium (Flavobacterium cloumnare G4), parasite (Ichthyophthirius multifiliis) and fungus (Saprolegnia). All of the four genes were differentially expressed in four tissues such as skin, gills, spleen and kidney in response to the pathogenic invasion, but both HSP70 and HSP90α expressions were dramatically up-regulated. Further, the cellular responses of the loach skinand gill tissues were observed, in which the number of the skin goblet cells were significantly increased, and the gill lamellae became shorter and wider after infected. Thus, our work indicated that the HSPs may directly or indirectly involved in immune defense in fish, at least in the loach.

A multiepitope peptide vaccine against HCV stimulates neutralizing humoral and persistent cellular responses in mice

BACKGROUND

Although DAAs hold promise to significantly reduce rates of chronic HCV infections, its eradication still requires development of an effective vaccine. Prolonged T cell responses and cross neutralizing antibodies are ideal for vaccination against the infection. We aimed to design and synthesize a 6 multi epitope peptide vaccine candidate and provide evidence for production of extended cellular and neutralizing Abs in mice.

METHODS

Six peptides derived from conserved epitopes in E1, E2 (n = 2),NS4B, NS5A and NS5B were designed, synthesized in a multiple antigenic peptide (MAP) form and administered w/o adjuvant to BALB/c mice as HCVp6-MAP at doses ranging from 800 ng to 16 μg. Humoral responses to structural epitopes were assayed by ELISA at different times after injection. ELISpot assay was used to evaluate IFN ɣ producing CD4+/ CD8+ T- lymphocytes at extended durations i.e. > 20 weeks. Viral neutralization by mice sera was tested for genotypes 2a (JFH1) and a chimeric 2a/4a virus (ED43/JFH1) in HCVcc culture.

RESULTS

HCVp6-MAP confers potent viral neutralization and specific cellular responses at > 1600 ng/ animal for at least 20 weeks.

CONCLUSION

We report on a promising anti HCV vaccine for future studies on permissive hosts and in clinical trials.

Tethering peptides onto biomimetic and injectable nanofiber microspheres to direct cellular response

Biomimetic and injectable nanofiber microspheres (NMs) could be ideal candidate for minimally invasive tissue repair. Herein, we report a facile approach to fabricate peptide-tethered NMs by combining electrospinning, electrospraying, and surface conjugation techniques. The composition and size of NMs can be tuned by varying the processing parameters during the fabrication. Further, bone morphogenic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) mimicking peptides have been successfully tethered onto poly(ε-caprolactone) (PCL):gelatin:(gelatin-methacryloyl) (GelMA)(1:0.5:0.5) NMs through photocrosslinking of the methacrylic group in GelMA and octenyl alanine (OCTAL) in the modified peptides. The BMP-2-OCTAL peptide-tethered NMs significantly promote osteogenic differentiation of bone marrow-derived stem cells (BMSCs). Moreover, human umbilical vein endothelial cells (HUVECs) seeded on VEGF mimicking peptide QK-OCTAL-tethered NMs significantly up-regulated vascular-specific proteins, leading to microvascularization. The strategy developed in this work holds great potential in developing a biomimetic and injectable carrier to efficiently direct cellular response (Osteogenesis and Angiogenesis) for tissue repair.

Cellular proteome datasets of human endothelial cells under physiologic state and after treatment with caffeine and epigallocatechin-3-gallate

Human endothelial cells play several significant roles in vascular biology and homeostasis. We report herein cellular proteome datasets of EA.hy926 human endothelial cells under physiologic condition and after treatment with 100 μM caffeine or EGCG for 24-h. Cellular proteins were extracted and subjected to in-solution tryptic digestion using filter-aided sample preparation (FASP) method. The digested peptides were analyzed by nanoflow liquid chromatography coupled to tandem mass spectrometry (nanoLC-ESI-Qq-TOF MS/MS). Finally, the mass spectral data were searched against the human Swiss-Prot database using Mascot 2.4 search engine and quantified using Skyline v.3.5 software and BiblioSpec algorithm. All of these data were used for further comparative proteomics study followed by bioinformatics analyses to investigate differential biochemical effects of caffeine and EGCG on human endothelial cells (Chanthick et al., 2019) [1].

Preclinical study of safety and immunogenicity of combined rubella and human papillomavirus vaccines: Towards enhancing vaccination uptake rates in developing countries

Rubella vaccine was not part of national immunization programs (NIP) in several countries in the Middle East and North Africa (MENA), South-East Asia (SEA), and South Africa regions until the year 2000. Therefore, immunization coverage of females older than 20 years old in these countries has been the focus of national campaigns for rubella elimination in developing countries. Vaccines against human papillomavirus (HPV) are not part of NIPs in developing countries. To enhance the advantages of rubella-directed immunization campaigns and to increase HPV vaccine uptake in developing countries, this study aimed to test the stability, potency, efficacy and safety of a combined rubella and HPV vaccine. Female BALB/c mice were immunized subcutaneously with proposed combined HPV16/HPV18 VLP and rubella vaccine at weeks (W) 0, 3 then with HPV vaccine at W 7. Immunized mice developed antigen-specific antibodies against rubella and HPV significantly higher than mice immunized with rubella or HPV vaccine alone. The combined vaccine induced significantly higher splenocyte proliferation than control groups. In addition, pro-inflammatory cytokines IL-4, IL-6, IL-2, and IFNγ levels were significantly higher in mice immunized with the combined vaccine than control groups. Overall, the combined vaccine was safe and immunogenic offering antibody protection as well as eliciting a cellular immune response against rubella and HPV viruses in a single vaccine. This combined vaccine can be of great value to females above 20 years old in the SEA, MENA and South Africa regions offering coverage to rubella vaccine and a potential increase in HPV vaccine uptake rates after appropriate clinical testing.

Mesenchymal stem cells transplanted into spinal cord injury adopt immune cell-like characteristics

Background

Mesenchymal stem cells (MSCs) and their cellular response to various stimuli have been characterized in great detail in culture conditions. In contrast, the cellular response of MSCs in an in vivo setting is still uncharted territory. In this study, we investigated the cellular response of MSCs following transplantation into spinal cord injury (SCI).

Methods

Mouse bone marrow-derived MSCs were transplanted 24 h following severe contusion SCI in mice. As controls, MSCs transplanted to the uninjured spinal cord and non-transplanted MSCs were used. At 7 days post transplantation, the MSCs were isolated from the SCI, and their global transcriptional changes, survival, differentiation, proliferation, apoptosis, and phenotypes were investigated using RNA sequencing, immunohistochemistry, and flow cytometry.

Results

MSCs transplanted into SCI downregulated genes related to cell-cycle regulation/progression, DNA metabolic/biosynthetic process, and DNA repair and upregulated genes related to immune system response, cytokine production/response, response to stress/stimuli, signal transduction and signaling pathways, apoptosis, and phagocytosis/endocytosis. MSCs maintained their surface expression of Sca1 and CD29 but upregulated expression of CD45 following transplantation. Transplanted MSCs maintained their surface expression of MHC-I but upregulated surface expression of MHC-II. Transplanted MSCs survived and proliferated to a low extent, did not express Caspase-3, and did not differentiate into neurons or astrocytes.

Conclusion

MSCs transplanted into SCI upregulate expression of CD45 and MHC-II and expression of genes related to cytokine production, phagocytosis/endocytosis, and immune cells/response and thereby adopt immune cell-like characteristics within the recipient.

Electronic supplementary material

The online version of this article (10.1186/s13287-019-1218-9) contains supplementary material, which is available to authorized users.