IL-10-/- Enhances DCs Immunity Against Chlamydia psittaci Infection via OX40L/NLRP3 and IDO/Treg Pathways

Neuroprotective effect of triptolide on neuronal inflammation in rats with mild brain injury

Concussions sustained while playing sports are a prominent cause of mild traumatic brain injury (mTBI), which is prevalent among teenagers. The early and intermediate stages of mild traumatic brain injury (mTBI) can be characterized by inflammation, neurodegeneration, and brain tissue edema, which can lead to permanent brain damage. The present study investigated the therapeutic effects of triptolide in mTBI and brain damage recovery. After building mTBI model in male rat, triptolide administrated daily for 1 week in the treated group. On day 3 and day 7 of administration, hippocampus tissues were collected to evaluate inflammation and autophagy in the brain. The expressions of inflammatory factors interleukin (IL)-1β and tumor necrosis factor-alpha in serum were downregulated, while IL-10 expression was upregulated when compared with the mTBI group on day 3 and day 7. The expression of IL-10 on day 7 was higher than on day 3. Quantitative polymerase chain reaction (qPCR) analysis of inflammatory-related factors (i.e., Il-1β and nuclear factor-κB (Nf-κb), and western blot as well as immunofluorescence staining of autophagy-related proteins (i.e., LC3B) and aquaporin (AQP 4) showed lower expression on day 3 and day 7 in the triptolide-treated group. Moreover, NeuN immunostaining, and hematoxylin and eosin (HE) staining for hippocampus region revealed that the triptolide-treated group showed a decrease in damaged cells. Our findings emphasize the effectiveness of triptolide therapy after mild traumatic brain injury via modulating autophagy, attenuating inflammation and reduces edema by decreasing AQP 4 expression.

Th17/Treg balance: the bloom and wane in the pathophysiology of sepsis

Sepsis is a multi-organ dysfunction characterized by an unregulated host response to infection. It is associated with high morbidity, rapid disease progression, and high mortality. Current therapies mainly focus on symptomatic treatment, such as blood volume supplementation and antibiotic use, but their effectiveness is limited. Th17/Treg balance, based on its inflammatory property, plays a crucial role in determining the direction of the inflammatory response and the regression of organ damage in sepsis patients. This review provides a summary of the changes in T-helper (Th) 17 cell and regulatory T (Treg) cell differentiation and function during sepsis, the heterogeneity of Th17/Treg balance in the inflammatory response, and the relationship between Th17/Treg balance and organ damage. Th17/Treg balance exerts significant control over the bloom and wanes in host inflammatory response throughout sepsis.

Feeding spray-dried plasma to broilers early in life improved their intestinal development, immunity and performance irrespective of mycotoxins in feed

Introduction

Fungi that produce mycotoxins can grow on certain food products, such as grains and feed, and can cause a variety of health issues if consumed by animals, including chickens. The use of spray-dried plasma (SDP) is one strategy for combating the health problems caused by mycotoxins.

Materials and methods

In the present study, Ross 308 chickens (n = 960) were divided into four treatment groups. T1 group was given a control diet (corn-soybean meal), T2 group was given a control diet +2% SDP, T3 group was given a control diet +2% SDP + mixture mycotoxins and T4 group was givena control diet + mycotoxin mixture.

Results

The presence of SDP resulted in weight gain and decreased feed efficiency, whereas mycotoxins resulted in weight loss and increased feed efficiency. SDP increased the thymus' relative weight. The presence of mycotoxins increased the heterophile/lymphocyte ratio. The presence of mycotoxins reduced the production of IL-2 and macrophage inflammatory protein-3 Alpha (MIP-3a), whereas the presence of SDP increased the production of macrophage colony-stimulating Factor (M-CSF). SDP resulted in higher IgA concentrations in the intestinal and tracheal washes than mycotoxin. Finally, adding SDP to broiler diets boosts weight gain, feed efficiency, and immune system development.

Discussion

Our results provide information supporting that SDP is a promising tool for improving poultry immunity and performance.

Reactive Oxygen Species Modulate Th17/Treg Balance in Chlamydia psittaci Pneumonia via NLRP3/IL-1β/Caspase-1 Pathway Differentiation

Chlamydia psittaci pneumonia (CPP) is a lung disease caused by the infection with the Chla-mydia psittaci bacterium, which can lead to severe acute respiratory distress syndrome and systemic symptoms. This study explored the specific mechanisms underlying the impact of reactive oxygen species (ROS) on the Th17/Treg balance in CPP. The levels of ROS and the differentiation ratio of Th17/Treg in the peripheral blood of healthy individuals and CPP patients were measured using ELISA and flow cytometry, respectively. The association between the ROS levels and Th17/Treg was assessed using Pearson correlation analysis. The ROS levels and the Th17/Treg ratio were measured in CD4+ T cells following H2O2 treatment and NLRP3 inhibition. The effects of H2O2 treatment and NLRP3 inhibition on the NLRP3/IL-1β/caspase-1 pathway were observed using immunoblotting. Compared to the healthy group, the CPP group exhibited increased levels of ROS in the peripheral blood, an elevated ratio of Th17 differentiation, and a decreased ratio of Treg differentiation. ROS levels were positively correlated with the Th17 cell proportion but negatively correlated with the Treg cell proportion. The ROS levels and NLRP3/IL-1β/caspase-1 expression were up-regulated in CD4+ T cells after H2O2 treatment. Furthermore, there was an increase in Th17 differentiation and a decrease in Treg differentiation. Conversely, the NLRP3/IL-1β/caspase-1 pathway inhibition reversed the effects of H2O2 treatment, with no significant change in the ROS levels. ROS regulates the Th17/Treg balance in CPP, possibly through the NLRP3/IL-1β/caspase-1 pathway. This study provides a new perspective on the development of immunotherapy for CPP.

TLR2 mediates autophagy through ERK signaling pathway in Chlamydia psittaci CPSIT_p7 protein-stimulated RAW264.7 cells

Chlamydia psittaci is a zoonotic pathogen found in birds and humans. Macrophages, major components of the innate immune system, can resist chlamydial infections and trigger adaptive immune responses. However, the molecular mechanisms underlying the action of macrophages against C. psittaci infection are not well understood. This study investigated the roles and mechanisms of plasmid-encoded protein CPSIT_p7 of C. psittaci in regulating autophagy in RAW264.7 cells. The results demonstrated that stimulation of RAW264.7 with C. psittaci plasmid protein CPSIT_p7 induced the expressions of the autophagy signaling primary regulators LC3 and Beclin1, which could also significantly induce the phosphorylation levels of ERK, JNK, p38, and Akt. Next, siRNA knockdown of TLR2 resulted in significant downregulation of CPSIT_p7-triggered autophagy in RAW264.7 cells. Moreover, the extracellular regulated protein kinase (ERK) inhibitor PD98059 markedly reduced autophagy in CPSIT_p7-stimulated macrophages. In summary, these results indicated that TLR2 plays an essential role in the induction of autophagy through the ERK signaling pathway in CPSIT_p7-stimulated RAW264.7 cells.

Blockade of Indoleamine 2,3-Dioxygenase attenuates lipopolysaccharide-induced kidney injury by inhibiting TLR4/NF-κB signaling

Blockade of indoleamine 2,3-dioxygenase (IDO) has been shown to alleviate lipopolysaccharide (LPS)-induced endotoxic shock and reduce sepsis mortality, but its effect on LPS-induced kidney damage has not been reported. Herein, we established a mouse kidney injury model by intraperitoneal injection of 10 mg/kg LPS and established an in vitro renal tubular epithelial cell injury model by stimulating TCMK-1 cells with 10 mg/L LPS. We found that pretreatment with 1-methyl tryptophan (1-MT), an IDO inhibitor, significantly improved LPS-induced mouse survival, and IDO knockout (KO) mice also had higher survival rates after LPS exposure than wild-type mice. At the same time, IDO KO or pretreatment with 1-MT not only reduced serum creatinine, blood urea nitrogen, renal tubular injury pathological score, but also inflammatory factors and oxidative stress status in serum or kidney of LPS-exposed mice. In vitro, blockade of IDO with 1-MT significantly inhibited LPS-induced apoptosis, inflammation and oxidative stress in TCMK-1 cells. In addition, blockade of IDO significantly inhibited LPS-activated TLR4/NF-κB signaling pathway in kidney of mice or in TCMK-1 cells. In conclusion, our results suggested that blockade of IDO attenuated kidney inflammation, apoptosis and oxidative stress to protect against LPS-induced septic kidney injury via inhibiting the TLR4/NF-κB signaling pathway.

Clinical and chest computed tomography features associated with severe Chlamydia psittaci pneumonia diagnosed by metagenomic next-generation sequencing: A multicenter, retrospective, observational study

Chlamydia psittaci pneumonia is a rare disease with varying clinical presentations. Here, we aimed to investigate the clinical and chest computed tomography (CT) features of severe psittacosis pneumonia. Clinical data of 35 patients diagnosed with psittacosis pneumonia were retrospectively analyzed using metagenomic next-generation sequencing. The patients were classified into severe (n = 20) and non-severe (n = 15) groups. The median age of patients was 54 years, and 27 patients (77.1%) had a definite history of bird contact. Severe patients had more underlying comorbidities and were more prone to dyspnea and consciousness disorders than non-severe patients. The neutrophil count and D-dimer, lactate dehydrogenase, interleukin (IL)-2, IL-6, and IL-10 levels were higher, whereas the lymphocyte, CD3 + T cell, and CD4 + T cell counts, CD4+/CD8 + T cell ratio, and albumin level were substantially lower in severe patients than in non-severe patients. Chest CT findings of severe patients revealed large areas of pulmonary consolidation, and ground-glass opacities were observed in some patients, with a higher risk of involving multiple lobes of the lungs and pleural effusion. One patient died of multiple organ failure, whereas the condition of the other 34 patients improved, and they were discharged from the hospital. Patients with severe psittacosis pneumonia often have underlying comorbidities and are prone to developing dyspnea, consciousness disorder, and lesions in both lungs. Serum D-dimer, IL-2, IL-6, and IL-10 levels and lymphocyte, CD3 + T cell, and CD4 + T cell counts are associated with disease severity.

Alternative strategies for Chlamydia treatment: Promising non-antibiotic approaches

Chlamydia is an obligate intracellular bacterium where most species are pathogenic and infectious, causing various infectious diseases and complications in humans and animals. Antibiotics are often recommended for the clinical treatment of chlamydial infections. However, extensive research has shown that antibiotics may not be sufficient to eliminate or inhibit infection entirely and have some potential risks, including antibiotic resistance. The impact of chlamydial infection and antibiotic misuse should not be underestimated in public health. This study explores the possibility of new therapeutic techniques, including a review of recent studies on preventing and suppressing chlamydial infection by non-antibiotic compounds.

Host inflammatory response is the major factor in the progression of Chlamydia psittaci pneumonia

Purpose

Chlamydia psittaci (C. psittaci) has caused sporadic, but recurring, fatal community-acquired pneumonia outbreaks worldwide, posing a serious threat to public health. Our understanding of host inflammatory responses to C. psittaci is limited, and many bronchitis cases of psittaci have rapidly progressed to pneumonia with deterioration.

Methods

To clarify the host inflammatory response in psittacosis, we analyzed clinical parameters, and compared transcriptomic data, concentrations of plasma cytokines/chemokines, and changes of immune cell populations in 17 laboratory-confirmed psittacosis cases, namely, 8 pneumonia and 9 bronchitis individuals, in order to assess transcriptomic profiles and pro-inflammatory responses.

Results

Psittacosis cases with pneumonia were found to have abnormal routine blood indices, liver damage, and unilateral pulmonary high-attenuation consolidation. Transcriptome sequencing revealed markedly elevated expression of several pro-inflammatory genes, especially interleukins and chemokines. A multiplex-biometric immunoassay showed that pneumonia cases had higher levels of serum cytokines (G-CSF, IL-2, IL-6, IL-10, IL-18, IP-10, MCP-3, and TNF-α) than bronchitis cases. Increases in activated neutrophils and decreases in the number of lymphocytes were also observed in pneumonia cases.

Conclusion

We identified a number of plasma biomarkers distinct to C. psittaci pneumonia and a variety of cytokines elevated with immunopathogenic potential likely inducing an inflammatory milieu and acceleration of the disease progression of psittaci pneumonia. This enhances our understanding of inflammatory responses and changes in vascular endothelial markers in psittacosis with heterogeneous symptoms and should prove helpful for developing both preventative and therapeutic strategies.

Somatic FOXC1 insertion mutation remodels the immune microenvironment and promotes the progression of childhood acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is the most common malignant hematological diseases in children. An immunosuppressive microenvironment, particularly regulatory T cell (Treg) infiltration, has been documented to be highly associated with childhood ALL. This present study, based on genetic factors, was aimed at investigating the mutations potentially involved in the immunosuppressive microenvironment in childhood ALL. After whole-exome sequencing was used on DNA extracted from the T cells of ALL bone marrow samples, we found the FOXC1 H446HG induced a increased Treg while decreased cytotoxic T lymphocyte (CTL) in bone marrow. The mutation of FOXC1 in T cell promoted the proliferation of leukemia cells in vitro and in vivo. CpG islands formed by insertion mutation led to an abnormal increase in exon methylation and were associated with the suppression of FOXC1. Decreased FOXC1 attenuated the transcription of HDAC1, thus resulting in the activation of KLF10 through increasing H3K27 acetylation in the promoter region. In conclusion, the de novo insertion mutation in FOXC1 induced suppression of FOXC1, thereby promoting a Treg/CTL shift in the ALL immune microenvironment. The FOXC1 H446HG mutation might be a potential therapeutic target for ALL in the future.