Lymphocyte apoptosis in children with central nervous system tuberculosis: a case control study

Area of Science:

• Immunology
• Infectious Diseases
• Pediatrics

Background:

• Tuberculosis pathogenesis involves Mycobacterium tuberculosis interfering with host cell apoptosis.
• Previous in vivo studies on apoptosis in tuberculosis have primarily focused on adult populations.
• The role of T lymphocyte apoptosis in pediatric central nervous system tuberculosis (CNS TB) remains understudied.

Purpose of the Study:

• To analyze spontaneous T lymphocyte apoptosis in children with CNS TB.
• To compare apoptosis levels before and after chemotherapy with healthy controls.
• To investigate the expression of apoptotic markers CD95 (Fas) and Fas ligand (FasL) in pediatric CNS TB.

Main Methods:

• A case-control study involving 18 children with CNS TB and 17 healthy controls.
• Evaluation of spontaneous apoptosis in peripheral blood T lymphocytes (PBTs), including CD4+, CD8+, and CD8+/CD28+ cells, using Annexin V detection.
• Assessment of CD95 (Fas) and Fas ligand (FasL) expression in lymphocyte populations before and after a 60-day chemotherapy regimen.

Main Results:

• Children with acute CNS TB exhibited higher percentages of apoptotic T cells and CD4 lymphocytes compared to controls (p < 0.05).
• Apoptotic T cell percentages significantly decreased after 60 days of treatment.
• Elevated Fas ligand expression and Fas-positive cells were observed in lymphocytes from children with CNS TB, both before and after treatment.
• A significant increase in apoptotic CD8+/CD28+ T cells was noted in acute CNS TB patients compared to controls.

Conclusions:

• Pediatric CNS TB enhances the sensitivity of CD4 and CD8+/CD28+ T cells to apoptosis, indicating a hypoergic immune status.
• This altered apoptosis likely contributes to the immunopathogenesis of CNS TB in children.
• Effective chemotherapy can restore normal apoptosis sensitivity and T-cell activation in pediatric patients with CNS TB.