The influenza A virus (IAV) belongs to the family Influenza Virus and subfamily Orthomyxoviridae. The IAV can cause acute infections of the lower respiratory in human and animals. Recently, many studies have been performed to reveal the lung CD4+ T cells, CD8+ T cells and Tregs via multiple effector and regulatory mechanisms to against IAV. In this paper, we review the state of progress with regards to various strategies of IAV escape from T cell responses, T cells and innate T cells immunity against influenza virus, which will provide a useful reference tool for future related reseach.
Animals ; Humans ; Influenza A virus ; immunology ; physiology ; Lung ; immunology ; virology ; T-Lymphocytes ; immunology

BACKGROUNDTo explore the pathological features and pathogenesis of severe acute respiratory syndrome (SARS) to provide evidence for the clinical treatment and prevention of SARS.

METHODSPathological features of 2 cases of full autopsy and 4 cases of needle biopsy tissue samples from the patients who died from SARS were studied by light and electron microscopy. The distribution and quantity of lymphocyte subpopulations in the lungs and immune organs from SARS patients were analyzed by immunohistochemistry. The location and semi-quantitative analysis of SARS coronavirus in the tissue specimens were studied by electron microscopy, in situ hybridization and immunohistochemistry.

RESULTSIn total of 6 cases, diffuse alveolar damage and alveolar cell proliferation were common. The major pathological changes of 2 autopsy cases of SARS in lung tissues were acute pulmonary interstitial and alveolar exudative inflammation, and 2 autopsy and one biopsy lung tissues showed alveolar hyaline membrane formation. Terminal bronchiolar and alveolar desquamation of lung tissues in one autopsy and 2 biopsy cases were noted. Among 6 cases, 2 biopsy cases presented early pulmonary fibrosis and alveolar organization. Meanwhile, the immune organs, including lymph nodes and spleens from 2 autopsy cases of SARS whose disease courses were less than 12 days showed extensive hemorrhagic necrosis, reactive macrophage/histocyte proliferation, with relative depression of mononuclear and granulocytic clones in the bone marrows. However, spleen and bone marrow biopsy tissue samples from 4 dead SARS cases whose clinical course lasted from 21 to 40 days presented repairing changes. SARS coronaviruses were mainly identified in type I and II alveolar epithelia, macrophages, and endothelia; meanwhile, some renal tubular epithelial cells, cardiomyocytes, mucosal and crypt epithelial cells of gastrointestinal tracts, parenchymal cells in adrenal glands, lymphocytes, testicular epithelial cells and Leydig's cells were also detected by electron microscopy combined with in situ hybridization. The semi-quantitative analysis of lymphocyte subpopulations revealed that the proportion of CD8+ T lymphocytes were about 80% of the total infiltrative inflammatory cells in the pulmonary interstitium, with a few CD4+ lymphocytes CD3+, CD4+, CD8+ or CD20+ lymphocyte subpopulations were obviously decreased and there was imbalance in number and proportion, while CD57+, CD68+, S-100+ and HLA-DR+ cells were relatively increased in lymph nodes and spleens.

CONCLUSIONSHistologically, the pulmonary changes could be divided into acute inflammatory exudative, terminal bronchiolar and alveolar desquamative and proliferative repair stages or types during the pathological process of SARS. SARS coronavirus was found in multi-target cells in vivo, which means that SARS coronavirus might cause multi-organ damages which were predominant in lungs. There were varying degrees of decrease and imbalance in number and proportion of lymphocyte subpopulations in the immune organs of the patients with SARS. However, these changes may be reversible. It was found that cellular immune responses were predominant in the lungs of SARS cases, which might play an important role in getting rid of coronaviruses in infected cells and inducing immune mediated injury.

Aged ; Female ; Humans ; Lung ; immunology ; pathology ; virology ; Lymphocyte Subsets ; immunology ; Male ; Middle Aged ; SARS Virus ; isolation & purification ; ultrastructure ; Severe Acute Respiratory Syndrome ; immunology ; pathology ; virology

OBJECTIVETo investigate the effect of respiratory syncytial virus (RSV) infection on the production of thymic stromal lymphopoietin (TSLP) and Th1/Th2 balance in asthmatic mice.

METHODSThirty-two female BALB/c mice were randomly divided into 4 groups, namely the PBS group, ovalbumin (OVA) group, RSV group and OVA/RSV group. The mice were sensitized by OVA and then stimulated with nebulized OVA, and RSV was inoculated into the nasal cavity of the mice. BUXCO noninvasive lung function detection was performed to examine the airway response to metacholine, and enzyme-linked immunosorbent assay (ELISA) was used to detect the serum levels of IL-4, IL-5, IL-13, and IFN-gamma in the mice. The cells in the bronchoalveolar lavage fluid (BALF) were counted and classified, and the supernatants of the BALF were used for the detection of TSLP. Histopathological changes in the lung tissues of the mice were examined using HE staining, and immunohistochemistry using anti-mouse TSLP antibody was performed to examine TSLP expressions in the airway epithelial cells.

RESULTSRSV infection promoted the production of TSLP in the asthmatic mice, and the concentration of TSLP in OVA/RSV group (2.13-/+0.05 ng/ml) was significantly higher than that in the other groups (P<0.01). RSV infection increased the serum levels of IL-4, IL-5, IL-13, and IFN-gamma in the mice. The total BALF cells, eosinophils, lymphocytes and neutrophils in OVA/RSV group were significantly higher than those in the other groups; noninvasive lung function examination showed higher Penh value in OVA/RSV group (318.66-/+50.87) than in the other groups when the inhaled metacholine increased to 6.25 mg/ml (P<0.01). More obvious and extensive airway inflammatory cell infiltration in OVA/RSV group were observed, and immunohistochemical staining also showed higher expression of TSLP in the airway epithelial cells of OVA/RSV group.

CONCLUSIONSRSV infection promotes the production of TSLP in the airway epithelial cells and increases the level of Th2 cytokines in asthmatic mice. Concurrent RSV infection can exacerbate Th2 inflammatory reaction in asthmatic mice.

Animals ; Bronchoalveolar Lavage Fluid ; Cytokines ; biosynthesis ; secretion ; Female ; Immunohistochemistry ; Inflammation ; immunology ; virology ; Interferon-gamma ; blood ; Interleukins ; blood ; Lung ; immunology ; metabolism ; virology ; Mice ; Mice, Inbred BALB C ; Respiratory Syncytial Virus Infections ; blood ; immunology ; metabolism ; Th2 Cells ; cytology ; immunology ; virology

OBJECTIVETo investigate the pathogenesis and immunogenicity of H9N2 influenza virus A/Guangzhou/333/99 (a reassortant of G1 and G9 viruses isolated from a female patient in 1999) in a mouse model of infection.

METHODSMice were infected with increasing virus titers. Viral load in the lungs and trachea was determined by EID50 assay. Pulmonary histopathology was assessed by hematoxylin-eosin staining. Anti-HI antibody titers and T-cell responses to viral HA were determined by ELISPOT and confirmed by flow cytometry.

RESULTSMice presented a mild syndrome after intranasal infection with A/Guangzhou/333/99 (H9N2) influenza virus. Virus was detected in the trachea and lungs of mice harvested on days 3, 6, and 9 post-infection. A T-cell response to viral HA was detected on day 6 and H9 HA-specific CD(4+) T-cells predominated. Seroconversion was detected after 14 days and antibody persisted for at least 28 weeks.

CONCLUSIONOur results suggest that H9N2 (A/Guangzhou/333/99) can replicate in the murine respiratory tract without prior adaptation, and both humoral and cell-mediated immunity play an important role in the immune response.

Animals ; CD4-Positive T-Lymphocytes ; immunology ; CD8-Positive T-Lymphocytes ; immunology ; Cell Line ; Dogs ; Enzyme-Linked Immunospot Assay ; Female ; Hemagglutination Inhibition Tests ; Hemagglutinins, Viral ; immunology ; Humans ; Infant ; Influenza A Virus, H9N2 Subtype ; immunology ; isolation & purification ; pathogenicity ; Interferon-gamma ; immunology ; Lung ; virology ; Lymphocytes ; immunology ; Mice ; Mice, Inbred BALB C ; Orthomyxoviridae Infections ; immunology ; virology ; Spleen ; immunology ; Trachea ; virology ; Viral Load ; Virulence

The tissue distribution and cellular localization of viral antigens in three cattle with persistent bovine viral diarrhea virus (BVDV) infection was studied. In three cases, necropsy findings of oral ulcers, abmasal ulcers and necrosis of Peyer's patches were suspected have been caused by BVDV infection. Non-cytopathic BVDV was isolated from a tissue pool of liver, kidneys and spleen. Immunohistochemical detection of BVDV showed that BVDV antigens were detected in both epithelial and nonepithelial cells in all examined organs, including the gastrointestinal tract, liver, pancreas, lung, lymphatic organs (spleen, lymph nodes), adrenal gland, ovary, uterus, and the mammary gland. These findings support the hypothesis that animals with persistent BVDV infection spread BVDV through all routes, and that infertility in BVDV infection is associated with the infection of BVDV in the ovaries and uteri.
Adrenal Glands/pathology/virology ; Animals ; Antigens, Viral/*isolation & purification ; Bovine Virus Diarrhea-Mucosal Disease/pathology/physiopathology/*virology ; Cattle ; Diarrhea Viruses, Bovine Viral/immunology/*isolation & purification ; Digestive System/pathology/virology ; Female ; Immunohistochemistry/veterinary ; Infertility, Female/virology ; Kidney/pathology/virology ; Lung/pathology/virology ; Lymphatic System/pathology/virology ; Mammary Glands, Animal/virology ; Ovary/pathology/virology ; Uterus/pathology/virology

Animals ; Antibodies, Neutralizing/biosynthesis* ; Antibodies, Viral/biosynthesis* ; Body Weight/immunology* ; COVID-19/virology* ; Disease Models, Animal ; Disease Progression ; Humans ; Immunohistochemistry ; Lung/virology* ; Male ; Mesocricetus ; Nasal Cavity/virology* ; RNA, Viral/immunology* ; SARS-CoV-2/pathogenicity* ; Severity of Illness Index ; Viral Load

OBJECTIVETo determine whether it could protect mice from challenge of lethal influenza virus which group prior infected A(H1N1) pdm09 and H9N2 virus respectively.

METHODS150 BALB/c mice are divided into three groups. Mice are infected A(H1N1) pdm09 virus (pCA07) and poultry H9N2 virus (GZ333) respectively. Infected mice are challenged with 10 times of lethal dose virus (PR8) then compare the viral load, antibody and survival of the two group mice before and after challenged.

RESULTSBoth experimental group mice survived after challenge of lethal influenza virus and lung viral load are lower than that of the first infection. Antibodies derived from the infective virus and challenge virus.

CONCLUSIONPrior infected A(H1N1) pdm09 and H9N2 virus could protect mice from challenge of lethal influenza virus.

Animals ; Antibodies, Viral ; immunology ; Female ; Humans ; Influenza A Virus, H1N1 Subtype ; physiology ; Influenza A Virus, H9N2 Subtype ; physiology ; Influenza, Human ; immunology ; prevention & control ; virology ; Lung ; immunology ; virology ; Mice ; Mice, Inbred BALB C ; Viral Load

OBJECTIVEIn order to understand the production mechanism of interferon and provide a scientific basis for preventionand clinical therapy, the expression changes of Toll-like receptor (TLR3) mRNA and the role of TLR3 in human lung epithelial cells (A549 cells) infected with respiratory syncytial virus (RSV) were investigated in this study.

METHODSRSV infected A549 cells were treated with or without specific antibodies of TLR3 and collected at the selected timepoints after RSV infection (4, 8, 12, 16 and 24h). The expressions of TLR3, IFN-alpha, IFN-beta and RSV F mRNA were evaluated by RT-PCR.

RESULTIt was found that RSV infection could markedly up-regulate the mRNA expression of TLR3, IFN-alpha, IFN-beta and RSV F protein in a time-dependent manner as the 24h mRNA expressions of them were 4 times, 3 times, 3 times and 0.7 times more than the basic expression, respectively. Treatment of TLR3 specific antibodies, whereas, significantly down-regulated the activation of TLR3. The mRNA expression of IFN-alpha and IFN-1beta also decreased accordingly and that of IFN-beta reduced more obviously than IFN-alpha, but that of RSV F protein rose significantly.

CONCLUSIONAbove data indicate that RSV infection could induce an apparent increase of antiviral genes of IFN-alpha and IFN-beta by activating TLR3 in human lung epithelial cells and the activated cells mediated Type I interferon is antiviral, which suggesting that TLR3 might play an important role in antiviral activity of RSV-infected human lung epithelial cells.

Epithelial Cells ; immunology ; virology ; Humans ; Interferon-alpha ; genetics ; Interferon-beta ; genetics ; Lung ; immunology ; virology ; RNA, Messenger ; analysis ; Respiratory Syncytial Viruses ; immunology ; Time Factors ; Toll-Like Receptor 3 ; genetics ; physiology ; Viral Fusion Proteins ; genetics

According to the classification of traditional Chinese medicine syndromes of coronavirus disease 2019 by the national competent authority, this study determined that human coronavirus 229 E(HCoV-229 E) was infected in a mouse model of cold and dampness syndrome, so as to build the human coronavirus pneumonia with pestilence attacking lung syndrome model. The model can simulate the traditional Chinese medicine treatment of common disease syndromes in Coronavirus Disease 2019 Diagnosis and Treatment Program(the sixth edition for trial). Specific steps were as follows. ABALB/c mouse model of cold and dampness syndrome was established, based on which, HCoV-229 E virus was infected; then the experiment was divided into normal control group, infection control group, cold-dampness control group, cold-dampness infection group(the model group), high-dose Chaiyin Particles group(8.8 g·kg~(-1)·d~(-1)), and low-dose Chaiyin Particles group(4.4 g·kg~(-1)·d~(-1)). On the day of infection, Chaiyin Particles was given for three consecutive days. Lung tissues were collected the day after the last dose, and the lung index and inhibition rate were calculated. The nucleic acid of lung tissue was extracted, and the HCoV-229 E virus load was detected by Real-time fluorescent quantitative RT-PCR. Blood leukocytes were separated, and the percentage of T and B lymphocytes was detected by flow cytometry. Lung tissue protein was extracted, and IL-6, IL-10, TNF-α and IFN-γ contents were detected by ELISA. High and low-dose Chaiyin Particles significantly reduced the lung index(P<0.01) of mice of human coronavirus pneumonia with pestilence attacking the lung syndrome, and the inhibition rates were 61.02% and 55.45%, respectively. Compared with the model control group, high and low-dose Chaiyin Particles significantly increased cross blood CD4~+ T lymphocytes, CD8~+T lymphocytes and total B lymphocyte percentage(P<0.05, P<0.01), and reduced IL-10, TNF-α and IFN-γ levels in lungs(P<0.01). In vitro results showed that TC_(50), TC_0, IC_(50) and TI of Chaiyin Particles were 4.46 mg·mL~(-1), 3.13 mg·mL~(-1), 1.12 mg·mL~(-1) and 4. The control group of in vitro culture cells had no HCoV-229 E virus nucleic acid expression. The expression of HCoV-229 E virus nucleic acid in the virus control group was 1.48×10~7 copies/mL, and Chaiyin Particles significantly reduced HCoV-229 E expression at doses of 3.13 and 1.56 mg·mL~(-1), and the expression of HCoV-229 E nucleic acid was 9.47×10~5 and 9.47×10~6 copies/mL, respectively. Chaiyin Particles has a better effect on the mouse model with human coronavirus pneumonia with pestilence attacking the lung syndrome, and could play a role by enhancing immunity, and reducing inflammatory factor expression.
Animals ; Coronavirus 229E, Human ; Coronavirus Infections ; immunology ; therapy ; Drugs, Chinese Herbal ; therapeutic use ; Humans ; Lung ; immunology ; virology ; Medicine, Chinese Traditional ; Mice ; Mice, Inbred BALB C

OBJECTIVETo observe the influence of the 4 parts of forming of Yiqi Qingwen Jidu Heji(YQQWJDHJ) to lung inflammatory cytokines of the model rats infected with influenza virus dynamically, and to discuss the mechanism of 4 parts of forming to anti-influenza immune injury and restoration.

METHODAt the different stages of infection with the model rats infected by FM1 influenza, expression in lung of TNF-alpha, IL-6, IL-1, IL-10 and IFN-gamma was detected after the intervention of 4 parts of forming using ELISA method.

RESULTThe expression of TNF-alpha, IL-6, IL-1 and IFN-gamma of model rats infected by FM1 were higher than the control group, the expression of IL-10 did not change. The expression of TNF-alpha was significantly reduced in 3 to 5 days after infection. By the method of relieving superficies with acrid-cold, clearing away heat and poison and replenishing Qi, the lung expression of IFN-gamma was significantly increased in the stage after infection. The method of relieving superficies with acrid-warm significantly reduced lung expression of IL-6 after infection in 1 to 3 days and on the 7th day, decreased the expression of IL-1 in 3 to 7 days, increased IFN-gamma expression on the 3rd day and the 7th day, and significantly increased the expression of IL-10 on the 1st day and in 5 to 7 days. The method of relieving superficies with acrid-cold reduced the expresssion of IL-6 after infection, and significantly increased the expression of IL-10. It could increase the expression of IL-1 after infection on the 3rd day, but reduced IL-1 expression after infection 7 days. The method of clearing away heat and poison reduced lung IL- 6 expression after infection in 3 to 7 days significantly, decreased the expression of IL-1 in 5 to 7 days, also increased the lung expression of IL-10 in 1 to 5 days significantly. The method of replenishing Qi significantly reduced the expression of IL-6 after infection on the 1st day and in 5 to 7 days, decreased the expression of IL-1 in 3 to 7 days, also significantly increased the lung IL-10 on the 5th day after infection.

CONCLUSIONThe method of clearing away heat and poison and replenishing Qi could be against the lung immune inflammatory damage and repair damage. The method of relieving superficies with acrid-warm demonstrated some immunity against lung injury on the 3rd day after infection and the method of relieving superficies with acrid-cold demonstrated some immunity against lung injury on the 5th days after infection.

Animals ; Chemistry, Pharmaceutical ; methods ; Cytokines ; immunology ; Disease Models, Animal ; Drugs, Chinese Herbal ; administration & dosage ; chemistry ; Humans ; Influenza, Human ; drug therapy ; immunology ; virology ; Influenzavirus A ; immunology ; physiology ; Lung ; drug effects ; immunology ; Male ; Mice ; Mice, Inbred BALB C ; Random Allocation ; Treatment Outcome