IL-12Rβ2 is essential for the development of experimental cerebral malaria

Area of Science:

• Immunology
• Pathology
• Neuroscience

Background:

• Th1 immune responses are critical for Plasmodium berghei ANKA (PbA)-induced experimental cerebral malaria (ECM).
• The role of the pro-Th1 cytokine Interleukin-12 (IL-12) in malaria pathogenesis is complex and debated.
• The specific contribution of IL-12 receptor beta 2 (IL-12Rβ2) to ECM development requires elucidation.

Purpose of the Study:

• To investigate the role of IL-12Rβ2 in the development of experimental cerebral malaria (ECM) following Plasmodium berghei ANKA (PbA) infection.
• To determine if IL-12Rβ2 signaling is essential for ECM pathogenesis, independent of IL-12p40 and IL-12p35.

Main Methods:

• Analysis of ECM development in C57BL/6 mice deficient in IL-12Rβ2, IL-12p40, or IL-12p35 after PbA infection.
• Noninvasive magnetic resonance imaging and angiography to assess ischemia and cerebral blood flow.
• Evaluation of T cell recruitment and gene expression, including key cytokines, in the brain.

Main Results:

• Mice lacking IL-12Rβ2 were completely resistant to ECM development and neurological symptoms.
• IL-12Rβ2-deficient mice exhibited normal cerebral microcirculation and absence of ischemia, unlike wild-type controls.
• Mice deficient in IL-12p40 or IL-12p35 remained susceptible to ECM.
• Resistance in IL-12Rβ2-deficient mice correlated with reduced T cell recruitment and lower expression of lymphotoxin-α, TNF-α, and IFN-γ in the brain.

Conclusions:

• IL-12Rβ2 signaling is essential and indispensable for the development of experimental cerebral malaria (ECM).
• The critical role of IL-12Rβ2 in ECM pathogenesis is independent of IL-12p40 and IL-12p35.
• A novel association between IL-12Rβ2 and the expression of key ECM-related cytokines (lymphotoxin-α, TNF-α, IFN-γ) was identified.