Evaluation the role of CD 4, CD8, CD56 and interleukin - 2 in pulmonary TB patients before and after treatment in waist province

Abstract

Background: Tuberculosis (TB) remains one of the leading infectious diseases worldwide despite the availability of effective chemotherapy. Host immune responses, particularly cell-mediated immunity, play a critical role in controlling Mycobacterium tuberculosis infection. Cellular immune biomarkers such as CD4⁺ T lymphocytes, CD8⁺ cytotoxic T cells, CD56⁺ natural killer (NK) cells, and the cytokine interleukin-2 (IL-2) have attracted considerable attention because of their potential value in monitoring disease progression and treatment response.

Objective: This study aimed to evaluate the immunological changes in CD4⁺, CD8⁺, CD56⁺ lymphocyte subsets and serum IL-2 concentrations among patients with pulmonary tuberculosis before and after anti-tuberculosis treatment in Wasit Province, Iraq.

Methods: A comparative case-control study was conducted involving pulmonary tuberculosis patients and healthy controls. Peripheral blood samples were collected before treatment and during anti-tuberculosis therapy. Flow cytometry was used to quantify CD4⁺, CD8⁺, and CD56⁺ lymphocyte populations, whereas serum IL-2 concentrations were determined using enzyme-linked immunosorbent assay (ELISA). Statistical analyses were performed to compare immunological parameters among the study groups, and correlations between immune markers and treatment status were evaluated.

Results: Patients with newly diagnosed pulmonary tuberculosis demonstrated significant alterations in cellular immune markers compared with healthy controls. CD4⁺ T-cell counts and serum IL-2 concentrations were markedly reduced before treatment, whereas gradual recovery was observed following anti-tuberculosis therapy. CD8⁺ T-cell and CD56⁺ NK-cell profiles also exhibited significant changes during treatment, suggesting restoration of cellular immune function. These findings indicate that successful chemotherapy is associated with progressive normalization of host immune responses.

Conclusion: CD4⁺, CD8⁺, CD56⁺ lymphocyte subsets and IL-2 represent valuable immunological biomarkers for evaluating immune status and monitoring treatment response in pulmonary tuberculosis patients. Their combined assessment may improve clinical follow-up and provide additional prognostic information beyond