Immunomodulatory role of chitosan-based nanoparticles and oligosaccharides in cyclophosphamide-treated mice

Ovarian microenvironment: challenges and opportunities in protecting against chemotherapy-associated ovarian damage

BACKGROUND

Chemotherapy-associated ovarian damage (CAOD) is one of the most feared short- and long-term side effects of anticancer treatment in premenopausal women. Accumulating detailed data show that different chemotherapy regimens can lead to disturbance of ovarian hormone levels, reduced or lost fertility, and an increased risk of early menopause. Previous studies have often focused on the direct effects of chemotherapeutic drugs on ovarian follicles, such as direct DNA damage-mediated apoptotic death and primordial follicle burnout. Emerging evidence has revealed an imbalance in the ovarian microenvironment during chemotherapy. The ovarian microenvironment provides nutritional support and transportation of signals that stimulate the growth and development of follicles, ovulation, and corpus luteum formation. The close interaction between the ovarian microenvironment and follicles can determine ovarian function. Therefore, designing novel and precise strategies to manipulate the ovarian microenvironment may be a new strategy to protect ovarian function during chemotherapy.

OBJECTIVE AND RATIONALE

This review details the changes that occur in the ovarian microenvironment during chemotherapy and emphasizes the importance of developing new therapeutics that protect ovarian function by targeting the ovarian microenvironment during chemotherapy.

SEARCH METHODS

A comprehensive review of the literature was performed by searching PubMed up to April 2024. Search terms included 'ovarian microenvironment' (ovarian extracellular matrix, ovarian stromal cells, ovarian interstitial, ovarian blood vessels, ovarian lymphatic vessels, ovarian macrophages, ovarian lymphocytes, ovarian immune cytokines, ovarian oxidative stress, ovarian reactive oxygen species, ovarian senescence cells, ovarian senescence-associated secretory phenotypes, ovarian oogonial stem cells, ovarian stem cells), terms related to ovarian function (reproductive health, fertility, infertility, fecundity, ovarian reserve, ovarian function, menopause, decreased ovarian reserve, premature ovarian insufficiency/failure), and terms related to chemotherapy (cyclophosphamide, lfosfamide, chlormethine, chlorambucil, busulfan, melphalan, procarbazine, cisplatin, doxorubicin, carboplatin, taxane, paclitaxel, docetaxel, 5-fluorouraci, vincristine, methotrexate, dactinomycin, bleomycin, mercaptopurine).

OUTCOMES

The ovarian microenvironment shows great changes during chemotherapy, inducing extracellular matrix deposition and stromal fibrosis, angiogenesis disorders, immune microenvironment disturbance, oxidative stress imbalances, ovarian stem cell exhaustion, and cell senescence, thereby lowering the quantity and quality of ovarian follicles. Several methods targeting the ovarian microenvironment have been adopted to prevent and treat CAOD, such as stem cell therapy and the use of free radical scavengers, senolytherapies, immunomodulators, and proangiogenic factors.

WIDER IMPLICATIONS

Ovarian function is determined by its 'seeds' (follicles) and 'soil' (ovarian microenvironment). The ovarian microenvironment has been reported to play a vital role in CAOD and targeting the ovarian microenvironment may present potential therapeutic approaches for CAOD. However, the relation between the ovarian microenvironment, its regulatory networks, and CAOD needs to be further studied. A better understanding of these issues could be helpful in explaining the pathogenesis of CAOD and creating innovative strategies for counteracting the effects exerted on ovarian function. Our aim is that this narrative review of CAOD will stimulate more research in this important field.

REGISTRATION NUMBER

Not applicable.

Zein and gum arabic nanoparticles: potential enhancers of immunomodulatory functional activity of selenium-containing peptides

Food-derived nanomaterials optimizing bioactive peptides is an emerging route in the functional food field. Zein and gum arabic (GA) possess favorable encapsulation properties for controlled release, targeted delivery and stabilization of food bioactive ingredients, and thus are considered as promising carriers for delivery systems. In order to improve the bioavailability of rice selenium-containing peptide TSeMMM (T), the nanoparticles (ZTGNs) containing peptide T, zein and GA have been previously prepared. This study focused on evaluating the immunomodulatory capacity of ZTGNs. The results showed that ZTGNs significantly alleviated cyclophosphamide-induced reduction in immune organ indices and liver glutathione content of mice. There was a significant upregulation observed in the levels of immune-related cytokines IL-6, TNF-α, and IFN-γ as well as their mRNA expression. Moreover, ZTGNs enriched the diversity of the intestinal flora and promoted the proportion of beneficial bacteria. In conclusion, ZTGNs have potential as immunomodulatory enhancers for food bioactive ingredients, providing prospects for further optimization of dietary supplements.

Unveiling the molecular mechanisms of Dendrobium officinale polysaccharides on intestinal immunity: An integrated study of network pharmacology, molecular dynamics and in vivo experiments

Intestinal immunity plays a pivotal role in overall immunological defenses, constructing mechanisms against pathogens while maintaining balance with commensal microbial communities. Existing therapeutic interventions may lead to drug resistance and potential toxicity when immune capacity is compromised. Dendrobium officinale, a traditional Chinese medicine, contains components identified to bolster immunity. Employing network pharmacology strategies, this study identified constituents of Dendrobium officinale and their action targets in the TCMSP and Swiss Target Prediction databases, and compared them with intestinal immunity-related targets. Protein-protein interaction networks revealed the core targets of Dendrobium officinale polysaccharides, encompassing key pathways such as cell proliferation, inflammatory response, and immune reactions, particularly in association with the Toll-like receptor 4. Molecular docking and molecular dynamics simulation further confirmed the high affinity and stability between Dendrobium officinale polysaccharides and Toll-like receptor 4. In vivo experiments demonstrated that Dendrobium officinale polysaccharides modulates the expression of Toll-like receptor 4 and its downstream key proteins in the colonic mucosa of mice. Consequently, these findings suggest that Dendrobium officinale polysaccharides may serve as a potential modulator for intestinal immune functions, with its mechanism potentially related to the Toll-like receptor 4.

Interventional Effect of Donkey Bone Collagen Peptide Iron Chelate on Cyclophosphamide Induced Immunosuppressive Mice

Immunodeficiency can disrupt normal physiological activity and function. In this study, donkey bone collagen peptide (DP) and its iron chelate (DPI) were evaluated their potential as immunomodulators in cyclophosphamide (Cytoxan®, CTX)-induced Balb/c mice. The femoral tissue, lymphocytes, and serum from groups of mice were subjected to hematoxylin and eosin (H&E) staining, methylthiazolyldiphenyl-tetrazolium bromide (MTT) cell proliferation assays, and enzyme-linked immunosorbent assay (ELISA), respectively. Furthermore, a non-targeted metabolomics analysis based on UPLC-MS/MS and a reverse transcription polymerase chain reaction (RT-qPCR) technology were used to explore the specific metabolic pathways of DPI regulating immunocompromise. The results showed that CTX was able to significantly reduce the proliferative activity of mouse splenic lymphocytes and led to abnormal cytokine expression. After DP and DPI interventions, bone marrow tissue damage was significantly improved. In particular, DPI showed the ability to regulate the levels of immune factors more effectively than Fe2+ and DP. Furthermore, metabolomic analysis in both positive and negative ion modes showed that DPI and DP jointly regulated the levels of 20 plasma differential metabolites, while DPI and Fe2+ jointly regulated 14, and all 3 jointly regulated 10. Fe2+ and DP regulated energy metabolism and pyrimidine metabolism pathways, respectively. In contrast, DPI mainly modulated the purine salvage pathway and the JAK/STAT signaling pathway, which are the key to immune function. Therefore, DPI shows more effective immune regulation than Fe2+ and DP alone, and has good application potential in improving immunosuppression.

The efficacy of cercarial antigen loaded on nanoparticles as a potential vaccine candidate in Schistosoma mansoni-infected mice

Schistosomiasis is one of the most common causes of morbidity and mortality from parasitic diseases. Mass treatment has proven to be insufficient because of repeated infection after treatment and the appearance of strains resistant to drug therapy. Hence, immunization is a new approach to control the disease and limit the pathological consequences of schistosomiasis. To evaluate the prophylactic effect of Cercarial antigen (CAP) loaded on chitosan nanoparticles (CSNPs) as a potential vaccine against Schistosoma mansoni-infected mice. 130 mice divided into 2 groups were used: Group I: Control groups (50 mice) subdivided into subgroup Ia (10 mice): Non-infected mice (normal control), subgroup Ib (20 mice): Schistosoma infected mice (infected control) and subgroup Ic (20 mice): Non-infected mice receiving NPs only. Group II: Vaccinated group (80 mice) subdivided equally into subgroup IIa (CAP): Received cercarial antigen and subgroup IIb (CAP + CSNP): Received cercarial antigen loaded on chitosan NPs then both vaccinated groups were infected with S. mansoni 3 weeks following the initial vaccination dose. CAP + CSNP and CAP groups showed significant reduction in adult worms count, hepatic egg count, hepatic granulomas number and size in comparison to the infected control group. Elevation of serum IgG and IgM levels, CD4+ and CD8+ T cell frequencies, IL-4, IL-10 and INF-γ levels was more significant in CAP + CSNP group than CAP group. CAP + CSNP is a promising new preparation of Schistosomal antigens that gave better results than immunization with CAP alone. CSNPs enhanced the immune and protective effect of CAP as validated by parasitological, histopathological and immunohistochemical studies.

Synthesis and characterization of chitosan for medical applications: A review

Chitosan has gained considerable recognition within the field of medical applications due to its exceptional biocompatibility and diverse range of properties. Nevertheless, prior reviews have primarily focused on its applications, offering limited insights into its source materials. Hence, there arises a compelling need for a comprehensive review that encompasses the entire chitin and chitosan life cycle: from the source of chitin and chitosan, extraction methods, and specific medical applications, to the various techniques employed in evaluating chitosan's properties. This all-encompassing review delves into the critical aspects of chitin and chitosan extraction, with a strong emphasis on the utilization of natural raw materials. It elucidates the various sources of these raw materials, highlighting their abundance and accessibility. Furthermore, a meticulous examination of extraction methods reveals the prevalent use of hydrochloric acid (HCl) in the demineralization process, alongside citric, formic, and phosphoric acids. Based on current review information, these acids constitute a substantial 69.2% of utilization, surpassing other mentioned acids. Of notable importance, the review underscores the essential parameters for medical-grade chitosan. It advocates for a degree of deacetylation (DDA) falling within the range of 85%-95%, minimal protein content <1%, ash content <2%, and moisture content <10%. In conclusion, these crucial factors contribute to the understanding of Chitosan's production for medical applications, paving the way for advancements in biomedical research and development.

Polymer-mediated nanoformulations: a promising strategy for cancer immunotherapy

Engineering polymer-based nano-systems have attracted many researchers owing to their unique qualities like shape, size, porosity, mechanical strength, biocompatibility, and biodegradability. Both natural and synthetic polymers can be tuned to get desired surface chemistry and functionalization to improve the efficacy of cancer therapy by promoting targeted delivery to the tumor site. Recent advancements in cancer immunoediting have been able to manage both primary tumor and metastatic lesions via activation of the immune system. The combinations of nano-biotechnology and immunotherapeutic agents have provided positive outcomes by enhancing the host immune response in cancer therapy. The nanoparticles have been functionalized using antibodies, targeted antigens, small molecule ligands, and other novel agents that can interact with biological systems at nanoscale levels. Several polymers, such as polyethylene glycol (PEG), poly(lactic-co-glycolic acid) (PLGA), poly(ε-caprolactone) (PCL), and chitosan, have been approved by the Food and Drug Administration for clinical use in biomedicine. The polymeric nanoformulations such as polymers-antibody/antigen conjugates and polymeric drug conjugates are currently being explored as nanomedicines that can target cancer cells directly or target immune cells to promote anti-cancer immunotherapy. In this review, we focus on scientific developments and advancements on engineered polymeric nano-systems in conjugation with immunotherapeutic agents targeting the tumor microenvironment to improve their efficacy and the safety for better clinical outcomes.

Lactobacillus plantarum modulate gut microbiota and intestinal immunity in cyclophosphamide-treated mice model

Gut microbiota (GM) contributes to the production of immune-regulatory molecules and cytokines. However, our understanding regarding intricate relationship between Lactobacillus plantarum and GM on regulation of immune function remained limited. To investigate the effect of Lactobacillus plantarum on an immunosuppressed mouse model, we employed cyclophosphamide treatment and conducted various analysis including H&E (hematoxylin-eosin staining), immunohistochemistry, 16S rRNA gene sequencing, and RT-PCR. Our results demonstrated that the administration of Lactobacillus plantarum had significant immunoenhancing effects in the immune-suppressed mice, as evidenced by the restoration of functional expression of specific immune markers in the spleen and an increase in the number of goblet cells in intestine (P < 0.05). Microbial taxonomic analysis revealed alterations in the gut microbiota composition, characterized by a decrease in the richness of Firmicutes and an increase in the proportion of Verrucomicrobia and Actinobacteria following cyclophosphamide treatment. Furthermore, cyclophosphamide treatment significantly suppressed the mRNA expression of inflammatory cytokines (P < 0.05), which were subsequently restored after administration of Lactobacillus plantarum. These observations provide valuable insights into the complex interplay between probiotics, gut microbiota, and immune system functioning.

An outlook on the target-based molecular mechanism of phytoconstituents as immunomodulators

The immune system is one of the essential defense mechanisms. Immune system inadequacy increases the risk of infections and cancer diseases, whereas over-activation of the immune system causes allergies or autoimmune disorders. Immunomodulators have been used in the treatment of immune-related diseases. There is growing interest in using herbal medicines as multicomponent agents to modulate the complex immune system in immune-related diseases. Many therapeutic phytochemicals showed immunomodulatory effects by various mechanisms. This mechanism includes stimulation of lymphoid cell, phagocytosis, macrophage, and cellular immune function enhancement. In addition increased antigen-specific immunoglobulin production, total white cell count, and inhibition of TNF-α, IFN-γ, NF-kB, IL-2, IL-6, IL-1β, and other cytokines that influenced the immune system. This review aims to overview, widely investigated plant-derived phytoconstituents by targeting cells to modulate cellular and humoral immunity in in vivo and in vitro. However, further high-quality research is needed to confirm the clinical efficacy of plant-based immunomodulators.

N-dihydrogalactochitosan reduces mortality in a lethal mouse model of SARS-CoV-2

The rapid emergence and global dissemination of SARS-CoV-2 that causes COVID-19 continues to cause an unprecedented global health burden resulting in nearly 7 million deaths. While multiple vaccine countermeasures have been approved for emergency use, additional treatments are still needed due to sluggish vaccine rollout, vaccine hesitancy, and inefficient vaccine-mediated protection. Immunoadjuvant compounds delivered intranasally can guide non-specific innate immune responses during the critical early stages of viral replication, reducing morbidity and mortality. N-dihydrogalactochitosan (GC) is a novel mucoadhesive immunostimulatory polymer of β-0-4-linked N-acetylglucosamine that is solubilized by the conjugation of galactose glycans with current applications as a cancer immunotherapeutic. We tested GC as a potential countermeasure for COVID-19. GC was well-tolerated and did not produce histopathologic lesions in the mouse lung. GC administered intranasally before and after SARS-CoV-2 exposure diminished morbidity and mortality in humanized ACE2 receptor expressing mice by up to 75% and reduced infectious virus levels in the upper airway. Fluorescent labeling of GC shows that it is confined to the lumen or superficial mucosa of the nasal cavity, without involvement of adjacent or deeper tissues. Our findings demonstrate a new application for soluble immunoadjuvants such as GC for preventing disease associated with SARS-CoV-2 and may be particularly attractive to persons who are needle-averse.

Effects of fungal based bioactive compounds on human health: Review paper

Since the first years of history, microbial fermentation products such as bread, wine, yogurt and vinegar have always been noteworthy regarding their nutritional and health effects. Similarly, mushrooms have been a valuable food product in point of both nutrition and medicine due to their rich chemical components. Alternatively, filamentous fungi, which can be easier to produce, play an active role in the synthesis of some bioactive compounds, which are also important for health, as well as being rich in protein content. Therefore, this review presents some important bioactive compounds (bioactive peptides, chitin/chitosan, β-glucan, gamma-aminobutyric acid, L-carnitine, ergosterol and fructooligosaccharides) synthesized by fungal strains and their health benefits. In addition, potential probiotic- and prebiotic fungi were researched to determine their effects on gut microbiota. The current uses of fungal based bioactive compounds for cancer treatment were also discussed. The use of fungal strains in the food industry, especially to develop innovative food production, has been seen as promising microorganisms in obtaining healthy and nutritious food.

The other side to the use of active targeting ligands; the case of folic acid in the targeting of breast cancer

Due to its overexpression in cancer cells, the folate receptor (FR) is heavily exploited in the active targeting of nanoparticles (NPs). Its ligand, folic acid (FA) is as a consequence widely used as a NP targeting ligand. Although rather popular and successful in principle, recent data has shown that FA may result in breast cancer initiation and progression, which questions the suitability of FA as NP cancer targeting ligand. In this work, intravenous administration of free FA to healthy female mice resulted in breast tissue dysplasia, hyperplasia and in the increased expression of human epidermal growth factor receptor-2 (HER2), folate receptor (FR), cancer antigen 15-3 (CA15.3), vascular endothelial growth factor (VEGF), signal transducer and activator of transcription 3 (STAT3) and the pro-inflammatory cytokines, tumor necrosis factor alpha (TNFα), interleukin-6 (IL-6) and interleukin-1β. In addition to the reduction in IL2. To evaluate the suitability and safety of FA as NP targeting ligand in breast cancer, small (≈ 150 nm) and large (≈ 500 nm) chitosan NPs were formulated and decorated with two densities of FA. The success of active targeting by FA was confirmed in two breast cancer cell lines (MCF-7 and MDA-MB-231 cells) in comparison to HEK293 cells. FA modified NPs that demonstrated successful active targeting in-vitro were assessed in-vivo. Upon intravenous administration, large NPs modified with a high density of FA accumulated in the breast tissue and resulted in similar effects as those observed with free FA. These results therefore question the suitability of FA as a targeting ligand in breast cancer and shed light on the importance of considering the activity (other than targeting) of the ligands used in NP active targeting.

Polysaccharide-based nanomedicines for cancer immunotherapy: A review

Cancer immunotherapy is an effective antitumor approach through activating immune systems to eradicate tumors by immunotherapeutics. However, direct administration of "naked" immunotherapeutic agents (such as nucleic acids, cytokines, adjuvants or antigens without delivery vehicles) often results in: (1) an unsatisfactory efficacy due to suboptimal pharmacokinetics; (2) strong toxic and side effects due to low targeting (or off-target) efficiency. To overcome these shortcomings, a series of polysaccharide-based nanoparticles have been developed to carry immunotherapeutics to enhance antitumor immune responses with reduced toxicity and side effects. Polysaccharides are a family of natural polymers that hold unique physicochemical and biological properties, as they could interact with immune system to stimulate an enhanced immune response. Their structures offer versatility in synthesizing multifunctional nanocomposites, which could be chemically modified to achieve high stability and bioavailability for delivering therapeutics into tumor tissues. This review aims to highlight recent advances in polysaccharide-based nanomedicines for cancer immunotherapy and propose new perspectives on the use of polysaccharide-based immunotherapeutics.

Advances in Engineered Polymer Nanoparticle Tracking Platforms towards Cancer Immunotherapy-Current Status and Future Perspectives

Engineering polymeric nanoparticles for their shape, size, surface chemistry, and functionalization using various targeting molecules has shown improved biomedical applications for nanoparticles. Polymeric nanoparticles have created tremendous therapeutic platforms, particularly applications related to chemo- and immunotherapies in cancer. Recently advancements in immunotherapies have broadened this field in immunology and biomedical engineering, where "immunoengineering" creates solutions to target translational science. In this regard, the nanoengineering field has offered the various techniques necessary to manufacture and assemble multifunctional polymeric nanomaterial systems. These include nanoparticles functionalized using antibodies, small molecule ligands, targeted peptides, proteins, and other novel agents that trigger and encourage biological systems to accept the engineered materials as immune enhancers or as vaccines to elevate therapeutic functions. Strategies to engineer polymeric nanoparticles with therapeutic and targeting molecules can provide solutions for developing immune vaccines via maintaining the receptor storage in T- and B cells. Furthermore, cancer immunotherapy using polymeric nanomaterials can serve as a gold standard approach for treating primary and metastasized tumors. The current status of the limited availability of immuno-therapeutic drugs highlights the importance of polymeric nanomaterial platforms to improve the outcomes via delivering anticancer agents at localized sites, thereby enhancing the host immune response in cancer therapy. This review mainly focuses on the potential scientific enhancements and recent developments in cancer immunotherapies by explicitly discussing the role of polymeric nanocarriers as nano-vaccines. We also briefly discuss the role of multifunctional nanomaterials for their therapeutic impacts on translational clinical applications.

Nanoparticles derived from insect exoskeleton modulates NLRP3 inflammasome complex activation in cervical cancer cell line model

Background

Immune evasion is an important hallmark of cancer progression and tumourigenesis. Among the cancer types, cervical cancer has very high global prevalence, severely affecting female reproductive health. Its preponderance is also observed in the Indian health sector.

Results

The NLRP3 inflammasome, an intracellular complex regulates the innate immune activity and a variant gene of it has been significantly associated with cervical cancer development. We aimed to evaluate the potential role of our chitosan engineered nanoparticles (CSNP) and gallic acid conjugated chitosan (gCSNP), to modulate the NLRP3 inflammasome complex in cervical cancer cell lines to explore their novel physicochemical properties. The encapsulation of gallic acid (GA) with chitosan was performed using ion gelation method. The CSNP and gCSNP nanoparticles ranged between 155 and 181 nm as determined by zeta sizer. The conjugations were validated by FTIR and XRD analysis. In the cervical cell line model, CSNP suppressed NLRP3 inflammasome activation in contrast to gCSNP at higher doses.

Conclusion

In contrast to gCSNP, the CSNP not only demonstrated inhibitory effect on the expression of genes coding for the NLRP3 inflammasome complex (signal 1—priming), but also decreased relative expression of gene involved in the activation of NLRP3 inflammasome complex (signal 2—activation). Conjugation of gallic acid reversed the immunosuppressor mimicking action of CSNP in cervical cancer cell line. Future research can reveal the immunomodulatory mechanism of CSNP may have its translational significance as potential treatment strategies targeting immune evasion as an important hallmark of cancer.

Graphical abstract

Antileishmanial potential of immunomodulator gallic acid against experimental murine visceral leishmaniasis

The menace of the enfeebling disease leishmaniasis prevails due to the inaccessibility of effective vaccine and chemotherapy. Hence in the pursuit of finding novel alternative options with reasonable efficacy, immunomodulation, leishmanicidal activity and fewer side effects, screening of compounds from natural sources is needed. This study was focused on in vitro and in vivo antileishmanial screening of gallic acid (GA) against Leishmania donovani infection in BALB/c mice. GA showed in vitro parasiticidal activity and IC₅₀  value of 19.59 ± 0.74 µg/ml and is able to arrest cell cycle at the sub-G0/G1 phase. The therapeutic potential of gallic acid was assessed in the L. donovani-infected BALB/c mice. GA reported a reduction in parasite burden and augmentation of CD4⁺ and CD8⁺ T lymphocytes. Also, the polarization of mouse immune status to protective Th1 response was evidenced by increased delayed-type hypersensitivity response and levels of IgG2a, reactive oxygen species and nitric oxide. GA was reported to be safe and non-toxic to human cell line THP-1 and also to the liver and kidney of mice. Hence, the findings of the present study indicate the possible role of GA in the strengthening of host immune system and thus facilitating the clearance of leishmanial infection and conferring protection.

The role of Chito-oligosaccharide in regulating ovarian germ stem cells function and restoring ovarian function in chemotherapy mice

In recent years, the discovery of ovarian germ stem cells (OGSCs) has provided a new research direction for the treatment of female infertility. The ovarian microenvironment affects the proliferation and differentiation of OGSCs, and immune cells and related cytokines are important components of the microenvironment. However, whether improving the ovarian microenvironment can regulate the proliferation of OGSCs and remodel ovarian function has not been reported. In this study, we chelated chito-oligosaccharide (COS) with fluorescein isothiocyanate (FITC) to track the distribution of COS in the body. COS was given to mice through the best route of administration, and the changes in ovarian and immune function were detected using assays of organ index, follicle counting, serum estrogen (E₂) and anti-Mullerian hormone (AMH) levels, and the expression of IL-2 and TNF-α in the ovaries. We found that COS significantly increased the organ index of the ovary and immune organs, reduced the rate of follicular atresia, increased the levels of E₂ and AMH hormones, and increased the protein expression of IL-2 and TNF-α in the ovary. Then, COS and OGSCs were co-cultured to observe the combination of COS and OGSCs, and measure the survival rate of OGSCs. With increasing time, the fluorescence intensity of cells gradually increased, and the cytokines IL-2 and TNF-α significantly promoted the proliferation of OGSCs. In conclusion, COS could significantly improve the ovarian and immune function of chemotherapy model mice, and improve the survival rate of OGSCs, which provided a preliminary blueprint for further exploring the mechanism of COS in protecting ovarian function.

Research Advances in Chitosan Oligosaccharides: From Multiple Biological Activities to Clinical Applications

Chitosan oligosaccharides (COS), hydrolysed products of chitosan, are low-molecular weight polymers with a positive charge and good biocompatibility. COS have recently been reported to possess various biological activities, including hypoglycaemic, hypolipidaemic, antioxidantantioxidant, immune regulation, anti-inflammatory, antitumour, antibacterial, and tissue engineering activities, exhibiting extensive application prospects. Currently, the biological processes and mechanisms of COS are attractive topics of study, ranging from the genetic, molecular and protein levels. This article reviews the recent discoveries about COS, especially in metabolic regulation, immune function and tissue repair, providing important insights into their multiple biological activities, medical benefits, and therapeutic mechanisms.

Particles Containing Cells as a Strategy to Promote Remyelination in Patients With Multiple Sclerosis

The repair of demyelinated lesions is a key objective in multiple sclerosis research. Remyelination fundamentally depends on oligodendrocyte progenitor cells (OPC) reaching the lesion; this is influenced by numerous factors including age, disease progression time, inflammatory activity, and the pool of OPCs available, whether they be NG2 cells or cells derived from neural stem cells. Administering OPCs has been proposed as a potential cell therapy; however, these cells can only be administered directly. This article discusses the potential administration of OPCs encapsulated within hydrogel particles composed of biocompatible biomaterials, via the nose-to-brain pathway. We also discuss conditions for the indication of this therapy, and such related issues as the influence on endogenous remyelination, migration of OPCs to demyelinated areas, and the immune response, given the autoimmune nature of multiple sclerosis. Chitosan and derivatives constitute the most promising biomaterial for this purpose, although these issues must be addressed. In conclusion, this line of research may yield an alternative to the remyelinating drugs currently being studied.

Effects of Polysaccharide from Malus halliana Koehne Flowers in Cyclophosphamide-Induced Immunosuppression and Oxidative Stress on Mice

The immunomodulatory effects of Malus halliana flower polysaccharide (MHFP) were investigated in this paper. The model of immunosuppressive mice was established by cyclophosphamide, which was treated with different dosages of MHFP (600, 400, and 200 mg/kg·d⁻¹). The results showed that MHFP significantly increased the index of the spleen and thymus and improved the atrophy of immune organs. MHFP enhanced the ability of carbon clearance and phagocytosis of mononuclear phagocytes in mice. Meanwhile, MHFP promoted the proliferation of splenic lymphocytes. MHFP could enhance the content of serum hemolysin and improve the decrease of hemolysin induced by cyclophosphamide. The contents of ACP and LDH in the serum and spleen were determined, indicating that MHFP could enhance the activity of macrophages. MHFP promoted the content of cytokines (IL-2, IL-6, TNF-α, and IFN-γ) and mRNA expression. At the same time, the pathological changes of the spleen tissue also showed that MHFP could improve the immunosuppression induced by cyclophosphamide. In addition, MHFP increased the content of SOD, T-AOC, and CAT in the serum and spleen tissue, decreased the level of MDA, and improved the oxidative stress caused by cyclophosphamide. In conclusion, MHFP could effectively improve the immunosuppression and oxidative stress induced by cyclophosphamide and enhance the immune capacity of mice.

Two different fucosylated chondroitin sulfates: Structural elucidation, stimulating hematopoiesis and immune-enhancing effects

Two fucosylated chondroitin sulfates FCS_hp and FCS_ht were isolated from the sea cucumber Holothuria polii and Holothuria tubulosa, respectively. The NMR spectroscopy and HILIC-FTMS methods were applied for their detailed structural characterization. Chemical analysis indicated that the two FCSs all contained a chondroitin sulfate backbone chondroitin sulfate-like core and fucosyl branches of α-L-Fuc2,4S, α-L-Fuc4S or α-L-Fuc3,4S linked to O-3 of glucuronic acid residues. The main branches of FCS_hp and FCS_ht were monofucose, and the small amounts of di-, tri- and tetrafucose with α-1,3-linkage type were also detected. Finally, we investigated the immunomodulatory function of FCS_hp and FCS_ht in cyclophosphamide (CTX)-induced immunosuppressed mouse models. The results showed that FCS_hp and FCS_ht had beneficial effects on hematopoietic function recovery in CTX-induced bone marrow suppression mice. Notably, the α-L-Fuc2,4S was more important to the activity than α-L-Fuc3,4S. These results provided basis for developing the drugs to reduce side effects of chemotherapy.

The Hemocompatibility of Nanoparticles: A Review of Cell-Nanoparticle Interactions and Hemostasis

Understanding cell-nanoparticle interactions is critical to developing effective nanosized drug delivery systems. Nanoparticles have already advanced the treatment of several challenging conditions including cancer and human immunodeficiency virus (HIV), yet still hold the potential to improve drug delivery to elusive target sites. Even though most nanoparticles will encounter blood at a certain stage of their transport through the body, the interactions between nanoparticles and blood cells is still poorly understood and the importance of evaluating nanoparticle hemocompatibility is vastly understated. In contrast to most review articles that look at the interference of nanoparticles with the intricate coagulation cascade, this review will explore nanoparticle hemocompatibility from a cellular angle. The most important functions of the three cellular components of blood, namely erythrocytes, platelets and leukocytes, in hemostasis are highlighted. The potential deleterious effects that nanoparticles can have on these cells are discussed and insight is provided into some of the complex mechanisms involved in nanoparticle-blood cell interactions. Throughout the review, emphasis is placed on the importance of undertaking thorough, all-inclusive hemocompatibility studies on newly engineered nanoparticles to facilitate their translation into clinical application.