Objective:To explore the expression and clinical significance of immunosuppressive receptor T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT) on the peripheral blood mononuclear cells (PBMC) in silicosis patients with Mycobacterium tuberculosis infection. Methods:August 2018, a total of 78 patients with silicosis (all were quarry workers in Sanmen County, Zhejiang Province) were enrolled and divided into silicosis combined with active pulmonary tuberculosis group (APTB group), silicosis combined with latent tuberculosis infection group (LTBI group), and simple silicosis with non-tuberculosis infection group (non-TB group). Flow cytometry was used to analyze the expressions of TIGIT, programmed death-1 (PD-1) and transcription factor T-bet on PBMC from patients. Mann-Whitney U test and Pearson correlations analysis were used for statistical analysis. Results:Among the 78 patients, eight were in the APTB group, 24 in the LTBI group, and 46 in the non-TB group. The expressions of PD-1 and TIGIT on CD8 + T cells in the APTB group (29.45%(16.78%) and 65.40%(12.12%), respectively) were significantly higher than those in the LTBI group (17.40%(11.17%) and 48.30%(28.75%), respectively; U=23.500 and 43.500, respectively, P=0.000 8 and 0.020 5, respectively) and non-TB group (15.95%(12.46%) and 45.30%(19.75%), respectively; U=64.000 and 69.000, respectively, P=0.002 3 and 0.003 8, respectively), and the differences were all statistically significant. The expression of TIGIT was positively correlated with PD-1 on CD8 + T cells in silicosis patients ( r=0.434 3, P<0.01). The proportion of PD-1 + TIGIT + CD8 + T cells in the APTB group (19.90%(22.67%)) was significantly higher than those in the non-TB group (11.55%(11.29%), U=76.500, P=0.007 1) and LTBI group (11.55%(10.53%), U=41.000, P=0.015 4), while the proportion of PD-1 -TIGIT -CD8 + T cells in the APTB group (30.60%(12.90%)) was significantly lower than non-TB group (48.90%(18.98%), U=58.000, P=0.001 3) and LTBI group (47.20%(24.59%), U=41.000, P=0.015 4). The differences were all statistically significant. The expression of T-bet on the peripheral blood CD8 + T cells in the APTB group (29.45%(16.78%)) was higher than that in the non-TB group (15.95%(12.46%)) and the LTBI group (17.40%(11.17%)), and the differences were both statistically significant ( U=46.500 and 46.000, respectively, P=0.000 3 and 0.028 3, respectively). The expression of T-bet on CD8 + T cells was positively correlated with TIGIT on CD8 + T cells ( r=0.456 7, P<0.01). The expression of T-bet on PD-1 + TIGIT + CD8 + T cells in the APTB group (65.40%(12.12%)) was higher than those in the LTBI group (48.30%(28.75%), U=23.500, P=0.000 8) and non-TB group (45.30%(19.75%), U=65.000, P=0.002 6), and the differences were both statistically significant. Conclusion:The immunosuppressive receptor PD-1 and TIGIT are highly expressed on CD8 + T cells in silicosis patients with active pulmonary tuberculosis, which indicates CD8 + T cells exhaustion in these population, while the highly co-expression of T-bet suggests the exhausted subsets may have reversed potentiality.

Objective:To investigate the diagnostic value of neutrophil CD64 index (nCD64) in disseminated nontuberculous mycobacteria (NTM) infection.Methods:Thirty-six patients with NTM infection from January 2020 to June 2021 in Huashan Hospital, Fudan University were included. Patients were classified into groups of disseminated infection and focal infection according to their medical history and discharge diagnosis. The expressions of nCD64 in patients with focal infection and disseminated infection before treatment were collected and analyzed. Statistical analysis was performed using the Mann-Whitney U test, and the diagnostic value of nCD64 for disseminated NTM infection was analyzed using the receiver operator characteristic curve (ROC curve). Results:Among the 36 patients with NTM infection, 18 cases were focal infection (due to the low white blood cell count of the patient with myelodysplastic syndrome, the detection results were biased, which were excluded from the subsequent analysis) and 18 cases were disseminated infection. The expression of nCD64 in focal infection was 0.72(0.50, 1.55), and that in disseminated infection was 13.63(6.77, 32.31). The difference was statistically significant ( U=15.50, P<0.001). Using focal infection as a control, the area under the ROC curve for the operational characteristics of the subjects was 0.949 3 for disseminated NTM infection. The diagnostic cut-off value of nCD64 was 3.06, with the sensitivity and specificity of the disseminated NTM infection were 88.89% and 100.00%, respectively. Conclusions:In patients with NTM infection before effective treatment, the diagnostic cut-off value of nCD64 of 3.06 has high sensitivity and specificity, which is useful for the aided diagnosis of disseminated NTM infection.

Objective:To analyze the differences of peripheral blood transcriptome between mild and severe influenza A (H1N1) patients, and to find indicators for the assessment of disease severity.Methods:A total of ten patients (five patients with mild disease and five patients with severe disease) diagnosed with H1N1 infection from January to May 2018 at Huashan Hospital, Fudan University in Shanghai were enrolled, and five healthy people were also enrolled as controls. The peripheral blood of patients was collected for transcriptome sequencing at the time when they were first diagnosed. Measurement data were compared using t test or Mann-Whitney U test. The count data were compared using Fisher exact test when appropriate. Data analysis of transcriptome predictions was performed using bioinformatics methods. Results:The platelet counts were significantly different between mild and severe groups ((163.4±21.5 )×10 9/L vs (255.6±52.5)×10 9/L, t=3.636, P=0.007). There were no differences between the two groups in gender, age, white blood cell counts, neutrophil percentage, lymphocyte percentage and hemoglobin levels (all P>0.05). However, the average expression levels of matrix metalloproteinase (MMP) 8 and MMP9 in severe group (18.41 and 174.00, respectively) were both higher than those in mild group (2.33 and 22.91, respectively) and healthy control (1.43 and 34.65, respectively; all P<0.01). Conclusion:MMP8 and MMP9 could be expected to serve as the molecular biological markers for predicting the disease severity in patients with influenza A (H1N1) infection.

Objective:To investigate the clinical features of nontuberculous mycobacteria (NTM) disease patients with positive anti-interferon γ (IFN-γ) autoantibody.Methods:Forty-three adult human immunodeficiency virus-uninfected patients with NTM disease hospitalized in Huashan Hospital, Fudan University and Jing′an Branch, Huashan Hospital, Fudan University from July 2021 to August 2023 were included. Clinical data and NTM strain information of the patients were collected. The plasma levels of anti-IFN-γ autoantibodies were detected by enzyme-linked immunosorbent assay, and the patients were divided into antibody positive group and antibody negative group. The clinical characteristics and laboratory examination results between the two groups were compared. The independent sample t test, Mann-Whitney U test and chi-square test were used for statistical analysis. Multivariate logistic regression analysis was used to determine the correlation factors of positive anti-IFN-γ autoantibodies. Results:Among the 43 patients, 13 cases (30.2%) were positive for anti-IFN-γ autoantibodies and 30 cases (69.8%) were negative. The proportions of patients with NTM disseminated infection (9/13 vs 30.0%(9/30))and combined bacterial infection (5/13 vs 6.7%(2/30)) in antibody positive group were both higher than those in antibody negative group, and the differences were both statistically significant ( χ2=5.74 and 6.73, respectively, both P<0.05). The white blood cell count, platelet count, the proportion of platelet count >350×10 9/L of antibody positive patients were all higher than those of antibody negative group, while the white sphere ratio was lower than that of antibody negative group, with statistical significance ( t=2.42, 3.02, χ2=9.77 and t=3.66, respectively, all P<0.05). Erythrocyte sedimentation rate, C-reactive protein, procalcitonin, globulin, immunoglobulin G, immunoglobulin A and immunoglobulin M in antibody positive patients were all higher than those in antibody negative group, and the differences were all statistically significant ( U=99.50, 112.00, 115.50, 61.50, 76.50, 99.00 and 83.00, respectively, all P<0.05). Mycobacterium abscessus complex (seven cases and 11 cases, respectively) and Mycobacterium avium complex (five cases and 13 cases, respectively) were the main isolated strains in antibody positive and antibody negative patients. Multivariate logistic regression analysis showed that combined with bacterial infection (odds ratio ( OR)=21.83, 95% confidence interval ( CI) 1.94 to 245.71), NTM disseminated infection ( OR=7.64, 95% CI 1.10 to 53.26), platelet count>350×10 9/L ( OR=14.31, 95% CI 1.91 to 107.04) were risk factors for anti-IFN-γ autoantibodies positive (all P<0.05). Conclusions:Patients with positive anti-IFN-γ autoantibodies have higher probability of having elevated levels of systemic inflammation. Anti-IFN-γ autoantibody test is recommended for patients with NTM disease who present with co-bacterial infection, NTM disseminated infection, or elevated platelet count (>350×10 9/L).

Objective:To explore the differences of gene expression profiles of precursors of exhausted T cells (Tpex) and terminal exhausted T cells (Tex) in the peripheral blood of patients with active pulmonary tuberculosis (ATB).Methods:Twenty-five cases of ATB, 13 cases of latent tuberculosis infection (LTBI) and 10 health controls were enrolled from January 2021 to October 2022 in the Fifth People′s Hospital of Wuxi. The proportions of Tpex and Tex in the peripheral blood mononuclear cells (PBMCs) of the three groups were detected by flowcytometry. PBMCs of ATB were separated into Tpex and Tex by fluorescence-activated cell sorting. RNA-sequencing was performed and up-regulated and down-regulated genes were screended. Differently expressed genes were analyzed by gene set enrichment analysis of gene ontology (GO) to find regulatory pathways affecting cell metabolism and function. Wilcoxon matched-pairs signed rank test, Kruskal-Wallis test and Dunn multiple comparsion test were used for statistical analysis.Results:The proportion of Tpex in ATB group was 2.86%(1.74%), which was lower than 7.93%(6.16%) of Tex, and the difference was statistically significant ( Z=-3.91, P<0.001). The proportions of Tpex and Tex in LTBI group were 9.47%(6.26%) and 7.43%(5.48%), respectively, and the difference was not statistically significant ( Z=-0.93, P=0.345). The proportions of Tpex and Tex in healthy control group were 8.42%(2.69%) and 6.49%(5.14%), respectively, with no statistical significance ( Z=-1.36, P=0.170). There was statistical difference of the proportion of Tpex among the three groups ( H=21.93, P<0.001), and the proportion of Tpex in ATB group was lower than those in LTBI and heathy control groups, and the differences were both statistically significant ( Z=4.16, P<0.001 and Z=3.34, P=0.003, respectively), while the proportions of Tex in these three groups were not statistically different ( H=2.17, P=0.338). Compared with Tex, the gene expressions of memory markers, such as B-cell lymphoma 2 of Tpex were up-regulated, and the gene expressions of exhausted markers, such as lymphocyte activation gene 3 were down-regulated. In terms of cellular metabolism, the gene expressions of mitochondrial protein complex, mitochondrial matrix and oxidative phosphorylation of Tpex were up-regulated, and the gene expressions of glycolysis were down-regulated. The gene expressions of pyruvate metabolism in Tex were up-regulated, and the gene expressions of CD4 + T lymphocyte activation and differentiation and glycolytic process in Tpex were down-regulated. Conclusions:Tpex in ATB express more characteristics of memory cells and less features of exhausted markers compared with Tex, and the function of mitochondria of Tpex preserves well.