Role of Helper, Cytotoxic T-cells and Interleukin-6 amongst Chronic Obstructive Pulmonary Disease Patients Post Exposure to Tobacco or Tuberculosis in Yaoundé Cameroon

Abstract

The pro-inflammatory cytokine Interleukin-6 (IL-6) –and T- T-cells play a major role in the pathogenesis and prognosis of many respiratory tract infections. Our study aimed to evaluate the role of T-Lymphocyte and IL-6 in Chronic Obstructive Pulmonary Disease (COPD) patients post-exposure to Tobacco or Tuberculosis. A cross-sectional prospective study was carried out from February 2021 to July 2022. Participants were enrolled at the Yaoundé Jamot Hospital. The intervention group comprised patients with post-TB/AFO (Tuberculosis/Airflow obstruction) and those with COPD related to tobacco, healthy subjects served as control. Spirometry results were obtained from the medical records. T-lymphocyte and IL-6 concentrations were measured by flow cytometry and ELISA (Enzyme-linked immunosorbent Assay) respectively. 150 participants were enrolled, 90 COPD patients and 60 healthy people. The COPD patients consisted of 50 with a history of smoking (COPD/tobacco) and 40 with a history of tuberculosis (post-TB/AFO). The level of IL-6 and CD4 cells (cluster differentiation) was higher in COPD patients compared to the control group (p-value 0.0001 and 0.0006 respectively). CD8 counts were higher in COPD/tobacco than in post-TB/AFO (p = 0.0043). IL-6 and CD4 were not statistically different between COPD/tobacco and post-TB/AFO. There was an inverse and non-significant correlation between IL-6 and CD8; and a non-significant positive correlation between IL-6 and CD4 with r = -0335, p = 0.087; R = 0.355; P = 0.069 respectively. IL-6 and CD8 T cells are involved in the pathogenesis of both COPD related to tobacco and post-TB airflow obstruction, with higher counts of blood CD8 cells in COPD/tobacco. Keywords: COPD, Inflammation, IL-6, T-lymphocyte, Tobacco, Tuberculosis.