The role of Interleukin-38 in modulating T cells in chronic Colitis: A mouse model study.

BACKGROUND: Interleukin (IL)-38 belongs to the IL-36 subfamily within the IL-1 family. Patients with inflammatory bowel diseases (IBD) exhibit higher levels of IL-38 in their intestinal tissue compared to healthy controls, suggesting that IL-38 may play a role in the pathogenesis of IBD. However, IL-38's impact on T cell-mediated immune responses in gastrointestinal inflammation has not been investigated. Therefore, the objective of this work was to elucidate the role of IL-38 in modulating T cells in a mouse model of dextran sulfate sodium (DSS)-induced chronic colitis. METHODS: Recombinant IL-38 (rIL-38) was administered intraperitoneally (i.p.) to mice with chronic colitis induced by DSS. Clinical symptoms, length of colon, and histologic alterations were assessed. Cytokine production was quantified using ELISA, and helper T (Th) cell subsets were evaluated via flow cytometry. RESULTS: Administration of recombinant IL-38 (rIL-38) alleviated DSS-induced chronic colitis. In addition, animals with chronic colitis treated with rIL-38 exhibited a significant decrease in the spontaneous production of inflammatory cytokines by neutrophils in the lamina propria. Furthermore, rIL-38 treatment increased the absolute numbers and percentages of regulatory T cells (Tregs) but decreased the absolute numbers and percentages of Th1 and Th17 cells. Moreover, rIL-38 treatment also decreased IL-17A-producing γδT cells substantially. CONCLUSION: This study's results show that IL-38 reduces the effects of chronic colitis caused by DSS by boosting Treg reactions and reducing Th1/Th17 reactions and IL-17A-producing γδT cells in LPL. Therefore, we propose that IL-38 has the potential to be utilized as a biological therapy agent for IBD.

Effects of omalizumab combined with budesonide formoterol on clinical efficacy, pulmonary function, immune function, and adverse reactions in children with moderate and severe allergic asthma.

OBJECTIVE: To evaluate the clinical efficacy and safety of combining omalizumab with budesonide formoterol to treat children with moderate and severe allergic asthma, and investigate the effect of this combination therapy on pulmonary and immune functions. METHODS: The data of 88 children with moderate and severe allergic asthma, who were admitted to our hospital between July 2021 and July 2022, were included in the study. The patients were randomly assigned either to control group (n = 44; received budesonide formoterol inhalation therapy) or experimental group (n = 44; received omalizumab subcutaneous injection + budesonide formoterol inhalation therapy) using computer-generated randomization. The clinical efficacy, asthma control (measured using childhood Asthma-Control Test [C-ACT] score), pulmonary function (forced expiratory volume in 1 s, forced vital capacity, and peak expiratory flow), immune function (cluster of differentiation 3 cells [CD3+ cells], cluster of differentiation 4 cells [CD4+ cells], immunoglobulin G, immunoglobulin A, and immunoglobulin E), and adverse reactions were observed and compared between both groups. RESULTS: After treatment, the experimental group had improved levels of pulmonary function and immune function indexes, higher C-ACT scores, and a higher overall response rate than the control group (P < 0.05). In addition, the incidence of adverse reactions was not significantly different between both groups (P > 0.05). CONCLUSION: The combination of omalizumab with budesonide formoterol for treating moderate and severe allergic asthma in children demonstrated promising clinical efficacy and improved their pulmonary and immune functions, leading to more rational asthma control. The combined regimen demonstrated satisfactory clinical safety and deserved clinical promotion.

Integrated transcriptomic and quantitative proteomic analysis identifies potential RNA sensors that respond to the Ag85A DNA vaccine.

OBJECTIVE: DNA vaccine has emerged as a promising approach with potential for Tuberculosis (TB) prevention in adults. However, the mechanism behind DNA vaccines is still largely unknown. MATERIALS AND METHODS: Utilizing the CRISPR/Cas9 technique, we engineered Ag85A mutated dendritic cells (Ag85A-M-DCs) in which the Ag85A mRNA derived from Mycobacterium tuberculosis was expressed but not the corresponding protein. Control cells (Ag85A-DCs) expressed both Ag85A mRNA and protein. To better understand the mechanism of antigen presentation following DNA vaccination, integrated transcriptomic and proteomic analysis of dendritic cells (DCs), Ag85A-DCs, and Ag85A-M-DCs were performed. RESULTS: A total of 723, 278, and 933 differentially expressed genes (DEGs), and 209, 134, and 509 differentially expressed proteins (DEPs) were identified between Ag85A-M-DCs and DCs, Ag85A-DCs and DCs, and Ag85A-M-DCs and Ag85A-DCs, respectively. Integration analysis detected 59, 15, and 64 associated DEGs/DEPs with the same expression trend between Ag85A-M-DCs and DCs, Ag85A-DCs and DCs, and Ag85A-M-DCs and Ag85A-DCs, respectively. KEGG pathway analysis showed that chemokine signaling pathway and MAPK signaling pathway were enriched in all three pairs of comparisons. The protein and protein interaction network revealed that ANXA1 was in the top 10 high-degree hub genes closely related to other genes in all three pairs of comparisons. CONCLUSION: The results indicated that Ag85A DNA vaccine might transmit immunogenicity information and induce immune responses by activating chemokine signaling pathway and MAPK signaling pathway. ANXA1 may serve as a key target molecule of the Ag85A vaccine with additional potential for TB prevention.

Improved antitumor efficacy of neutrophils stimulated by bacillus Calmette­Guérin.

Bacillus Calmette­Guérin (BCG) has become a significant treatment for bladder cancer, and neutrophils are reported to be associated with the antitumor effect of BCG. The aim of the present study was to clarify the antitumor function of neutrophils stimulated by BCG. Initially, the killing effect and cytotoxic activity of neutrophils treated with BCG was detected. Subsequently, the effectiveness of BCG­treated neutrophils extracted from tumor­bearing mice was analyzed. The results revealed that the cytotoxic effect of neutrophils was stronger in the BCG­treated group compared with that in the normal saline (NS)­treated and control groups (P<0.05). A significantly higher concentration of cytokines tumor necrosis factor (TNF)­α, interleukin (IL)­1ß, IL­6 and TNF­related apoptosis­inducing ligand occurred in the BCG­treated neutrophil group compared with the NS and control groups (P<0.01), which was also associated with the BCG dose (P<0.01). The gross tumor volume percentage in BCG­treated neutrophils from tumor­bearing mice (BCGT group) was significantly lower in comparison with that in the NS­treated neutrophils from tumor­bearing mice (NST group; P<0.05). In addition, the survival rate of tumor­bearing mice was higher in the BCGT group compared with the NST group (P<0.05), while more BCG­treated neutrophils from tumor­bearing mice were infiltrated in the MethA tumor (P<0.01). In conclusion, BCG­treated neutrophils were observed to enhance the antitumor efficacy and extend the life span of mice.

Dendritic cell vaccine with Ag85A enhances anti-colorectal carcinoma immunity.

Dendritic cells (DCs) are able to trigger T-cell activation and thus have been considered important for vaccine production against cancers. Vaccines containing DCs have been reported to be effective for developing immunity against cancer cells. The interactions between DCs and auxiliary agents are critical in the development of second-generation vaccines. In the present study, it was evaluated whether Ag85A-mixed DCs could enhance anti-tumor immunity in laboratory mice with colorectal carcinoma. Functional and phenotypic analyses of the effects of Ag85A-mixed DCs were conducted via flow cytometry and measurement of T-cell proliferation. In addition, interferon (IFN)-γ production was assessed. The therapeutic efficacy of DC vaccination for colorectal carcinoma treatment in mice was investigated. It was identified that Ag85A-mixed DCs exhibited strong upregulation of CD80, CD86 and major histocompatibility complex class II. Cytotoxic T-lymphocytes with CT26-primed Ag85A-DCs were indicated to induce stronger responses against CT26 tumor cells and trigger IFN-γ production. Furthermore, the Ag85A-mixed DC vaccine exerted a considerable inhibitory effect on tumor progression in mice as compared with the control group. Therefore, DCs in combination with the Ag85A gene may reinforce anti-colorectal carcinoma immunity. The current study provides a novel potential strategy for cancer treatment by enhancing immunity via Ag85A-mixed DC vaccination.

IL-33 Protects Mice against DSS-Induced Chronic Colitis by Increasing Both Regulatory B Cell and Regulatory T Cell Responses as Well as Decreasing Th17 Cell Response.

BACKGROUND: Previously, we have reported that IL-33 functioned as a protective modulator in dextran sulfate sodium- (DSS-) induced chronic colitis by suppressing Th17 cell response in colon lamina propria and IL-33 induced both regulatory B cells (Bregs) and regulatory T cells (Tregs) in mesenteric lymph nodes (MLNs) of mice with DSS-induced acute colitis. Moreover, we speculated that IL-33 would promote the Treg or Breg responses leading to the attenuation of DSS-induced chronic colitis. So, we investigated the role of IL-33 on Bregs and Tregs in the MLN of DSS-induced chronic colitis mice. METHODS: IL-33 was administered by intraperitoneal injection to mice with DSS-induced chronic colitis. Clinical symptoms, colon length, and histological changes were determined. The production of cytokines was measured by ELISA. The T and B cell subsets were measured by flow cytometry. The expression of mRNA of transcription factors was measured by quantitative real-time PCR. RESULTS: We show that IL-33 treatment increases both Breg and Treg responses in the MLN of mice with DSS-induced chronic colitis. Moreover, IL-33 treatment also decreases Th17 cell response in the MLN of mice with DSS-induced chronic colitis. CONCLUSION: Our data provide clear evidence that IL-33 plays a protective role in DSS-induced chronic colitis, which is closely related to increasing Breg and Treg responses in the MLN of mice as well as suppressing Th17 cell responses.

Suppression of Th17 Cell Response in the Alleviation of Dextran Sulfate Sodium-Induced Colitis by Ganoderma lucidum Polysaccharides.

BACKGROUND: Ganoderma lucidum polysaccharides (GLP) has anti-inflammatory and immunomodulatory effects. Dysregulated immune responses are involved in the pathogenesis of dextran sulfate sodium (DSS)-induced colitis. The aim of this study was to assess the therapeutic potential of GLP to alleviate DSS-induced colitis. METHODS: The mice were administered with GLP by intragastric gavage daily for two weeks prior to the DSS treatment. Mice were orally administered with 2.5% DSS dissolved in drinking water with GLP or water treatment for 6 days. The mice were killed on day 7 after induction of colitis. Survival rates, body weight loss, colon lengths, histological changes, and disease activity index scores (DAI) were evaluated. RESULTS: GLP significantly improved survival rates, colon length shortening, body weight loss, histopathological score, and DAI scores in mice with DSS-induced colitis. GLP markedly suppressed the secretions of TNF-α, IL-1ß, IL-6, IL-17A, and IL-4 and significantly affected populations of Th17 cells, B cells, NK cells, and NKT cells in the lamina propria lymphocytes. CONCLUSIONS: GLP prevented inflammation, maintained intestinal homeostasis, and regulated the intestinal immunological barrier functions in mice with DSS-induced colitis.

The mechanisms of Ag85A DNA vaccine activates RNA sensors through new signal transduction.

Low immunogenicity is one of the major problems limiting the clinical use for DNA vaccines, which makes it impossible to obtain a strong protective immune response after vaccination. In order to explore whether Ag85A DNA vaccine could mount more efficiently protective immune response through new RNA sensor and its signal transduction pathway of antigen presentation we designed and synthesized Ag85A gene fragment containing multiple points mutations and transfected the gene fragment into the dendritic cell line (DC2.4) by CRISPR/Cas9. Subsequently, we focused on the changes of RNA sensors RIG-I, Mda-5, and the downstream adaptors MAVS, IRF3, IRF7 and IFN-ß. The results indicated the significant increases in the mRNA and protein expression of RNA sensors RIG-I, Mda-5 and related adaptors MAVS, IRF3, IRF7, and IFN-ß in the mutant DC 2.4 cells. The flow cytometry results demonstrated that the expression of MHC II on the surface of DC 2.4 significantly increased when compared with that in control. Therefore, it is suggested that Ag85A mutant DNA could release immunogenic message through RNA sensors and related adaptors via non protein pathway. There is at least one RNA signal transduction pathway of Ag85A DNA in DC2.4 cell. The work provides a new mode of action for nucleic acid vaccine to improve immunogenicity and meaningful data for the better understanding of the mechanisms of DNA vaccine.

Pioglitazone Improves Mitochondrial Function in the Remnant Kidney and Protects against Renal Fibrosis in 5/6 Nephrectomized Rats.

Pioglitazone is a type of peroxisome proliferator-activated receptor γ (PPARγ) agonist and has been demonstrated to be effective in chronic kidney diseases (CKD) treatment. However, the underlying mechanism involved in the renoprotection of pioglitazone has not been fully revealed. In the present study, the renoprotective mechanism of pioglitazone was investigated in 5/6 nephrectomized (Nx) rats and TGF-ß1-exposed HK-2 cells. Pioglitazone attenuated renal injury and improved renal function, as examined by 24 h urinary protein, blood urea nitrogen and plasma creatinine in Nx rats. Renal fibrosis and enhanced expressions of profibrotic proteins TGF-ß1, fibronectin and collagen I caused by Nx were significantly alleviated by pioglitazone. In addition, pioglitazone protected mitochondrial functions by stabilizing the mitochondrial membrane potential, inhibiting ROS generation, maintaining ATP production and the activities of complexes I and III, and preventing cytochrome C leakage from mitochondria. Pioglitazone also upregulated the expression levels of ATP synthase ß, COX I and NDUFB8, which were downregulated in the kidney of Nx rats and TGF-ß1-exposed HK-2 cells. Furthermore, pioglitazone increased fusion proteins Opa-1 and Mfn2 expressions and decreased fission protein Drp1 expression. The results imply that pioglitazone may exert the renoprotective effects through modulating mitochondrial electron transport chain and mitochondrial dynamics in CKD. Finally, these recoveries were completely or partly inhibited by GW9662, which suggests that these effects at least partly PPARγ dependent. This study provides evidence for the pharmacological mechanism of pioglitazone in the treatment of CKD.

Rab5a is overexpressed in oral cancer and promotes invasion through ERK/MMP signaling.

Ras-related protein Rab-5A (Rab5a) has been identified to be overexpressed in several types of human cancer. However, its clinical significance and biological roles in oral cancer remain unclear. In the present study, the protein expression of Rab5a was examined in 79 cases of oral squamous cell carcinoma samples using immunohistochemistry. It was demonstrated that Rab5a protein was upregulated in 49.3% (39/79) of cancer samples. Small interfering RNA knockdown was performed on Detroit 562 cells with high endogenous expression. Rab5a transfection was performed in FaDu cells with low endogenous levels. Rab5a depletion was revealed to inhibit cell growth, invasion and colony formation while its overexpression facilitated cell growth, invasion, and colony formation. In addition, Rab5a facilitated cell cycle progression and cell migration. It was also demonstrated that Rab5a depletion downregulated and its overexpression upregulated the expression levels of various cell cycle­associated proteins, and matrix metalloproteinase­2 (MMP­2). Furthermore, Rab5a positively regulated the extracellular signal­regulated kinase (ERK) signaling pathway and promoted epithelial­mesenchymal transition (EMT). ERK inhibitor PD98059 partially inhibited the role of Rab5a on MMP­2, cyclin D1, cell proliferation and invasion. The results of the present study suggest that Rab5a is overexpressed in oral cancer tissue samples and promotes the malignant phenotype through EMT and the ERK/MMP­2 signaling pathway.