Background & Objectives: Perforin is one of the major effector molecules of cytotoxic cells associated with killing of cells harbouring intracellular bacterial infection. The precise role of perforin positive cells in tuberculosis still remains controversial. The present study was done to determine the number of circulating CD4(+) and CD8(+) perforin positive cells to assess the level of cytotoxic response against Mycobacterium tuberculosis in patients with pulmonary tuberculosis.
Methods: Intracellular perforin and surface CD4 and CD8 staining of peripheral blood lymphocytes was done using specific monoclonal antibodies and enumerated using flowcytometry.
Results: A significantly decreased total lymphocytes (P<0.01), CD4 (P<0.001) and CD8 (P<0.01) lymphocyte counts in PTB patients was observed compared to normal healthy individuals (NHS). Intracellular perforin staining showed significantly elevated percentages of total (P<0.05) and CD8 (P<0.01) perforin positive cells in PTB patients compared to NHS. However, the absolute counts of total, CD4 and CD8 cells positive for perforin were similar in patients and NHS.
Interpretation & Conclusion: Our results suggest that during active stage of pulmonary tuberculosis there was an increased percentage of CD8 cells positive for perforin, irrespective of their absolute counts. Further, CD8(+) perforin positive cells may have increased cytolytic activity against M. tuberculosis in active pulmonary tuberculosis.
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J Clin Invest
January 2025
Program in Infectious Diseases and Global Health, The Research Institute of the McGill University Health Centre, Montréal, Canada.
Natural resistance to Mycobacterium tuberculosis (Mtb) infection in some people with HIV (PWH) is unexplained. We performed single cell RNA-sequencing of bronchoalveolar lavage cells, unstimulated or ex vivo stimulated with Mtb, for 7 PWH who were TST & IGRA positive (called LTBI) and 6 who were persistently TST & IGRA negative (called resisters). Alveolar macrophages (AM) from resisters displayed a baseline M1 macrophage phenotype while AM from LTBI did not.
View Article and Find Full Text PDFJ Transl Med
January 2025
Joint Research Center for Occupational Medicine and Health of IHM, School of Medicine, Anhui University of Science and Technology, Huainan, Anhui, 232000, China.
Background: PRDX2 is significantly expressed in various cancers and is associated with the proliferation of tumor cells. Nonetheless, the precise mechanism of PRDX2 in tumor immunity remains incompletely understood. This study aims to investigate the impact of PRDX2, which is highly expressed in lung adenocarcinoma, on T cells in the tumor immune microenvironment, and its immune action target to promote the immune escape of lung cancer cells, to provide a theoretical basis for lung adenocarcinoma treatment with PRDX2 as the target.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Department of Medical Microbiology and Immunology, Medical School, University of Pecs, 12 Szigeti Street, 7624 Pecs, Hungary.
Pregnancy involves significant immunological changes to support fetal development while protecting the mother from infections. A growing body of evidence supports the importance of immune checkpoint pathways, especially at the maternal-fetal interface, although limited information is available about the peripheral expression of these molecules by CD8+ and CD8- NK cell subsets during the trimesters of pregnancy. Understanding the dynamics of these immune cells and their checkpoint pathways is crucial for elucidating their roles in pregnancy maintenance and potential complications.
View Article and Find Full Text PDFBiomedicines
November 2024
Peking University People's Hospital, Peking University Institute of Hematology, National Clinical Research Center for Hematologic Disease, Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, Beijing 100044, China.
Compared to other immune checkpoint molecules, T cell immunoglobulin domain and mucin domain-3 (TIM-3) is highly expressed on natural killer (NK) cells, but its functional role and prognostic significance in acute myeloid leukemia (AML) remains unclear. This study aims to evaluate the role of TIM-3 expression on the cytotoxic and killing capacity of NK cells and its prognostic significance in AML. AML public single-cell RNA sequencing (scRNAseq) data were used to analyze the correlation of transcript levels between (encoding TIM-3) and cytotoxic molecules in NK cells.
View Article and Find Full Text PDFZhonghua Xue Ye Xue Za Zhi
November 2024
Department of Hematology, Nanfang Hospital, Southern Medical University, Clinical Medical Research Center of Hematological Diseases of Guangdong Province, Guangzhou 510515, China.
This study aimed to investigate the association between early immune reconstitution and Epstein-Barr virus (EBV) reactivation by analyzing changes in natural killer (NK), B, and T cells and their functional status in the peripheral blood during the early post-transplant period. This study included 23 patients who underwent haplo-hematopoietic stem cell transplantation (HSCT). The immune reconstitution of NK cells, T cells, and B cells as well as the expression levels of NK and T cell exhaustion markers (PD-1, TIM-3, and CTLA-4) and cytotoxic function at 1, 2, and 3 months post-transplantation were compared between patients with EBV activation (EBV+ group) and those without activation (EBV- group) post- transplantation.
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