How tumour necrosis factor blockers interfere with tuberculosis immunity

Area of Science:

• Immunology
• Infectious Diseases
• Pharmacology

Background:

• Tumour necrosis factor (TNF) is crucial for immunity against bacterial infections like Mycobacterium tuberculosis (Mtb).
• Anti-TNF agents (e.g., infliximab, adalimumab) treat inflammatory diseases but are linked to TB reactivation.
• These drugs can disrupt various immune responses beyond TNF blockade.

Purpose of the Study:

• To review the effects of TNF blockers on immune cell responses.
• To correlate these immune effects with clinical data on TB reactivation in patients receiving anti-TNF therapy.

Main Methods:

• Literature review of reported effects of TNF blockers on immune responses.
• Analysis of clinical data linking anti-TNF therapy to TB reactivation.

Main Results:

• Anti-TNF drugs interfere with innate immunity (phagolysosomal maturation, monocyte apoptosis).
• Cell-mediated immunity is affected, including T cell responses (interferon-gamma secretion, CD8+ T cell lysis) and regulatory T cell activity.
• Observed immune dysregulation correlates with increased risk of TB reactivation.

Conclusions:

• TNF blockers can impair critical immune mechanisms required to control Mycobacterium tuberculosis.
• Understanding these immune effects is essential for managing TB risk in patients on anti-TNF therapy.
• Further research is needed to mitigate TB reactivation associated with anti-TNF treatments.