Lymphocyte subpopulations in pulmonary tuberculosis patients

Area of Science:

• Immunology
• Infectious Diseases
• Cell Biology

Background:

• Cell-mediated immunity, particularly CD4(+) and CD8(+) T-cells, is crucial for protection against Mycobacterium tuberculosis.
• Understanding immune cell profiles in tuberculosis is vital for developing effective treatments.

Purpose of the Study:

• To evaluate CD4(+) and CD8(+) T-cell profiles, B-lymphocytes (CD19(+)), and natural killer (NK) cells (CD3(+)CD(16+56)(+)) in pulmonary tuberculosis patients.
• To compare these immune cell populations between active pulmonary tuberculosis (APTB), inactive pulmonary tuberculosis (IPTB), and healthy controls (HCs).

Main Methods:

• Flow cytometry was used to analyze percentages of CD4(+), CD8(+), CD19(+), and NK cells in 75 APTB, 25 IPTB, and 20 HCs.
• Immune cell profiles were compared between groups and within APTB patients based on treatment stage and X-ray findings.

Main Results:

• APTB patients exhibited significantly lower CD4(+) T cells and higher NK cells compared to HCs (P < .01).
• IPTB patients showed significantly decreased CD8(+) T cells and increased NK cells compared to HCs (P < .05 and P < .01, respectively).
• No significant differences in CD4(+), CD8(+), B-lymphocyte, or NK cell percentages were observed across different treatment stages or disease severity in APTB patients.

Conclusions:

• Active pulmonary tuberculosis is associated with a reduced percentage of circulating CD4(+) T cells and an elevated percentage of NK cells.
• These altered immune cell populations may play significant roles in the host's immune response to Mycobacterium tuberculosis infection.