Treatment of Alopecia Areata with Anti-Interferon-Gamma Antibodies

The document reports on a study investigating the role of type-1 cytokines, specifically interferon-gamma (IFN-γ) and interleukin-2 (IL-2), in the pathogenesis of alopecia areata (AA) using C3H/HeJ mice. The study found that mice genetically modified to lack IFN-γ (IFN-γ-/-) were resistant to AA development after being grafted with lesional AA skin from affected mice, indicating a crucial role of IFN-γ in AA. Similarly, mice with reduced IL-2 expression (IL-2 +/-) showed a significantly lower frequency of AA development, suggesting that the level of IL-2 expression influences AA development. The study involved grafting skin to induce AA, where 90% of normal control mice developed AA, but none of the IFN-γ-/- mice and only 47% of IL-2 +/- mice did. Immunohistochemistry and FACS analysis showed reduced T cell activation in these genetically modified mice. Additionally, the document describes a clinical trial where 16 patients with AA, aged 6-15 years, were treated with anti-IFN-γ antibodies. The treatment led to stabilization of the disease and hair regrowth in several patients, particularly those with patchy, progressive hair loss. The results suggest that early intervention with anti-IFN-γ therapy could be effective for AA, and the study plans to use humanized monoclonal anti-IFN-γ antibodies in future treatments.