Tumor necrosis factor (cachectin) in human visceral leishmaniasis

Area of Science:

• Immunology
• Infectious Diseases
• Parasitology

Background:

• Visceral leishmaniasis (VL) is a severe parasitic disease.
• Tumor necrosis factor-alpha (TNF alpha) is a pro-inflammatory cytokine.
• The role of TNF alpha in VL pathogenesis and treatment response requires further elucidation.

Purpose of the Study:

• To investigate serum TNF alpha levels in patients with active VL, cryptic leishmanial infections, and tegumentary leishmaniasis.
• To assess the impact of leishmanial infection on macrophage TNF alpha production.
• To evaluate serum TNF alpha levels as a marker for monitoring treatment response in VL.

Main Methods:

• Serum samples were collected from active VL patients, patients with cryptic leishmanial infection, tegumentary leishmaniasis patients, and healthy volunteers.
• TNF alpha levels were measured using immunoassays.
• In vitro studies assessed TNF alpha production by human monocyte-derived macrophages infected with Leishmania and treated with interferon-gamma.

Main Results:

• Active VL patients exhibited significantly elevated serum TNF alpha levels compared to controls and patients with other forms of leishmaniasis.
• Leishmanial infection enhanced TNF alpha production by macrophages, further increased by interferon-gamma.
• Successful VL treatment led to a rapid decline in serum TNF alpha levels, preceding normalization of clinical parameters.
• Non-responsive patients maintained elevated TNF alpha levels.

Conclusions:

• Serum TNF alpha is a reliable biomarker for active visceral leishmaniasis.
• Serum TNF alpha levels serve as an early indicator of host response to VL therapy.
• Monitoring TNF alpha levels can aid in assessing treatment efficacy and guiding patient management.