gp130 on macrophages/granulocytes modulates inflammation during experimental tuberculosis

Area of Science:

• Immunology
• Infectious Diseases
• Cytokine Signaling

Background:

• gp130 is a shared receptor for cytokines like IL-27 and IL-6.
• IL-27 generally limits inflammation and enhances T helper cell responses in tuberculosis (TB).
• gp130 cytokines also suppress macrophage inflammatory responses, suggesting a role in regulating cytokine secretion.

Purpose of the Study:

• To investigate the specific role of gp130 cytokines in macrophage and neutrophil function during experimental TB.
• To determine if gp130 signaling in these myeloid cells influences the immune response and disease outcome in TB.

Main Methods:

• Utilized macrophage/neutrophil-specific gp130-deficient (LysM(cre) gp130(loxP/loxP)) mice.
• Analyzed the outcome of experimental TB infection in these genetically modified mice.
• Assessed inflammatory cytokine induction, NOS2 and LRG47 expression, T helper 17 (TH17) responses, and matrix metalloproteinase (MMP)-9 levels.

Main Results:

• LysM(cre) gp130(loxP/loxP) mice showed enhanced inflammatory cytokine induction and increased NOS2, LRG47, TH17, and MMP-9 expression.
• Despite amplified inflammation, these mice did not exhibit reduced bacterial loads or altered TB pathology.
• This indicates an immunoregulatory role for gp130 cytokines on macrophages/granulocytes.

Conclusions:

• gp130 cytokines play an immunoregulatory role in macrophages and granulocytes during TB.
• This specific gp130-mediated regulation in myeloid cells is not critical for controlling bacterial burden or disease progression in experimental TB.