Humans ; Norepinephrine ; Bacterial Infections/drug therapy* ; Immunity, Innate

Objective To observe the expression of adhesion molecule CD226 on the small intestinal group 3 innate lymphoid cells (ILC3) in mice. Methods The bioinformatics was used to analyze the expression of CD226 on murine ILCs. Small intestinal mucosal lamina propria lymphocytes (LPL) were isolated from wild-type C57BL/6J mice, and the expression of CD226 on ILC1 and ILC3 was detected by flow cytometry. A mouse model of dextran sulfate sodium (DSS)-induced colitis was constructed to observe the changes in the expression of CD226 on ILC3. Results Both ILC1 and ILC3 in the mice small intestine expressed CD226 molecules; the proportion of ILC3 was reduced, while the expression level of CD226 on ILC3 was increased in the colitis model. Conclusion CD226 is expressed on the small intestines of mice, and although the proportion of ILC3 decreases in the DSS-induced colitis, the expression of CD226 on ILC3 increases.
Animals ; Mice ; Colitis/chemically induced* ; Immunity, Innate ; Intestine, Small ; Lymphocytes ; Mice, Inbred C57BL

Background: The association of obesity with adverse COVID-19 outcomes is known, but unexplored in younger adults. Objective: To determine the association of obesity [body mass index (BMI) of ≥30] with severe COVID-19 outcomes in younger and older adults. Design: Retrospective cohort study. Participants: 391 patients with COVID-19 (226 younger adults aged 18-60 years, and 165 older adults aged >60 years). Setting: Southern Philippines Medical Center, Davao City, January 2021 to September 2021. Main outcome measures: Severe COVID-19 outcomes (high-flow oxygen administration, ICU admission, mechanical ventilation, death); odds ratio of severe outcomes in patients with BMI of ≥30. Main results: Of 391 patients (median age of 57 years), 286 had a BMI of <30, while 105 had a BMI of ≥30. Univariate regression analysis showed that a BMI of ≥30 was significantly associated with any severe COVID-19 outcomes (OR=2.68; 95% CI 1.68 to 4.27; p<0.001). This remained after adjusting for age, sex, hypertension, diabetes, and cardiovascular disease (adjusted OR=3.19; 95% CI 1.93 to 5.27; p<0.001). A BMI of ≥30 was also significantly associated with any severe outcomes among younger adults (adjusted OR=4.04; 95% CI 2.23 to 7.32; p<0.001), but not among older adults (adjusted OR=1.80; 95% CI 0.70 to 4.64; p=0.227). Conclusion In our study, among all adults, a BMI of ≥30 significantly increased the odds of experiencing any severe COVID-19 outcomes. This association was also observed in the younger adult subgroup, but not in the older adult subgroup.
SARS-CoV-2 ; Body Mass Index ; Immunity ; Critical Care

Humans ; Mass Vaccination ; COVID-19 Vaccines/therapeutic use* ; COVID-19/prevention & control* ; Immunity, Herd ; Vaccination

Humans ; Vaccines, Inactivated ; COVID-19/prevention & control* ; Vaccination ; Viral Vaccines ; Immunity ; Antibodies, Viral

Bacillus cereus is a common foodborne pathogen. Accidently eating food contaminated by B. cereus will cause vomiting or diarrhea, and even death in severe cases. In the present study, a B. cereus strain was isolated from spoiled rice by streak culture. The pathogenicity and drug resistance of the isolated strain were analyzed by drug sensitivity test and PCR amplification of virulence-associated gene respectively. Cultures of the purified strain were injected intraperitoneally into mice to examine their effects on intestinal immunity-associated factors and gut microbial communities, to provide references for the pathogenic mechanism and medication guidance of these spoilage microorganisms. The results showed that the isolated B. cereus strain was sensitive to norfloxacin, nitrofurantoin, tetracycline, minocycline, ciprofloxacin, spectinomycin, clindamycin, erythrocin, clarithromycin, chloramphenicol, levofloxacin, and vancomycin, but resistant to bactrim, oxacillin and penicillin G. The strain carries seven virulence-associated genes including hblA, hblC, hblD, nheA, nheB, nheC and entFM, which are involved in diarrhea-causing toxins production. After infecting mice, the isolated B. cereus strain was found to cause diarrhea in mice, and the expression levels of immunoglobulins and inflammatory factors in the intestinal mucosae of the challenged mice were significantly up-regulated. Gut microbiome analysis showed that the composition of gut microbial community in mice changed after infection with B. cereus. The abundance of the uncultured_bacterium_f_Muribaculaceae in Bacteroidetes, which is a marker of body health, was significantly decreased. On the other hand, the abundance of uncultured_bacterium_f_Enterobacteriaceae, which is an opportunistic pathogen in Proteobacteria and a marker of dysbacteriosis, was significantly increased and was significantly positively correlated with the concentrations of IgM and IgG. These results showed that the pathogenic B. cereus carrying diarrhea type virulence-associated gene can activate the immune system by altering the composition of gut microbiota upon infection.
Animals ; Mice ; Bacillus cereus/metabolism* ; Food Microbiology ; Immunity, Mucosal ; Diarrhea ; Microbiota ; Enterotoxins/genetics*

Nearly a quarter of the world's population is infected with Mycobacterium tuberculosis and remains long-term asymptomatic infection. Rv2626c is a latent infection-related protein regulated by DosR of M. tuberculosis. In this study, the Rv2626c protein was prokaryotically expressed and purified, and its immunobiological characteristics were analyzed using RAW264.7 cells and mice as infection models. SDS-PAGE and Western blotting analysis showed that the Rv2626c-His fusion protein was mainly expressed in soluble form and specifically reacted with the rabbit anti-H37RV polyclonal serum. In addition, we found that the Rv2626c protein bound to the surface of RAW264.7 macrophages and up-regulated the production of NO. Moreover, the Rv2626c protein significantly induced the production of pro-inflammatory cytokines IFN-γ, TNF-α, IL-6 and MCP-1, and induced strong Th1-tendency immune response. These results may help to reveal the pathogenic mechanism of M. tuberculosis and facilitate the development of new tuberculosis vaccine.
Animals ; Mice ; Rabbits ; Mycobacterium tuberculosis/genetics* ; Tuberculosis ; Antigens, Bacterial ; Cytokines ; Immunity, Cellular

Group 2 innate lymphoid cells (ILC2s) are the "mirror cells" of Th2 cells. Although the total cell number of ILC2s is far less than that of CD4⁺ Th2 cells in the body, the activated ILC2s have a more powerful biological activity than CD4⁺ Th2 cells and can rapidly enhanced Th2-cell inflammatory reaction. It plays an important role in the pathogenesis of allergic respiratory diseases. The transmitters that activate ILC2s include inflammatory cytokines (IL-33, IL-25, TSLP, IL-4, IL-9), lipid transmitters (prostaglandins, leukotrienes), and other activating transmitters (ICOS, Complement C3a, neuropeptide receptor, vasoactive intestinal peptide and calcitonin gene-related peptide, etc). Activated ILC2s produce large amounts of IL-4, IL-5, IL-9, IL-13, and amphiregulin and other inflammatory mediators, and induce airway hyperresponsiveness, mucus secretion and airway remodeling and other respiratory allergic reactions. Therefore, respiratory allergic diseases, especially steroid-dependent asthma, could be treated potentially by inhibiting the activation of ILC2s. Hereby, we summarized the immunobiology of ILC2s, the initiation of ILC2s in allergic inflammation, the relationship between ILC2s and respiratory allergic diseases, and the recent advances in biological agents targeted by ILC2s.
Humans ; Immunity, Innate ; Interleukin-4 ; Interleukin-9 ; Lymphocytes ; Hypersensitivity ; Cytokines ; Respiratory Tract Diseases ; Inflammation

Group 3 innate lymphoid cells (ILC3) are an ILC subset that is characterized by the expression of retinoic acid-related orphan nuclear receptor γt (RORγt) and interleukin 22 (IL-22). This review summarizes the role of ILC3 in coordinating innate immunity and adaptive immunity based on current research and elaborate the significance of ILC3 from the perspective of immune system evolution. In addition, based on immune-related functions, we propose a possible time when ILC3 appears in the evolution of the immune system. And then, the research limitations and prospects are discussed.
Immunity, Innate ; Lymphocytes ; Tretinoin

Objective To investigate the relationship between intestinal inflammatory group 2 innate lymphoid cells (iILC2s) and lung ILC2s and its inflammatory response in chronic obstructive pulmonary disease (COPD). Methods Mouse COPD model was established by smoking method. The mice were randomly divided into normal group and COPD group. HE staining was used to detect the pathological changes in lung and intestine tissues of mice in normal group and COPD group, and the contents of natural ILC2s(nILC2s) and iILC2s cells were measured by flow cytometry. Wright-Giemsa staining was used to measure the number of immune cells in the bronchoalveolar lavage fluid (BALF) of mice in normal group and COPD group, and the concentration of IL-13 and IL-4 was detected by ELISA. Results In COPD mice, epithelial cells of the lung and intestinal tissues exhibited pathological hyperplasia, partial atrophy or deletion, inflammatory cell infiltration, increased pathological score and significantly increased neutrophils, monocytes, and lymphocytes in BALF. Lung iILC2s, intestinal nILC2s and iILC2s were increased significantly in the COPD group. The contents of IL-13 and IL-4 in BALF were significantly increased. Conclusion The increase of iILC2s and their related cytokines in COPD lung may be related to intestinal inflammatory ILC2s.
Mice ; Animals ; Cytokines ; Immunity, Innate ; Interleukin-13 ; Interleukin-4 ; Lymphocytes ; Lung/pathology* ; Pulmonary Disease, Chronic Obstructive ; Bronchoalveolar Lavage Fluid ; Disease Models, Animal ; Intestines