Neutralization of Interleukin-10 Significantly Enhances Gamma Interferon Expression in Peripheral Blood by Stimulation with Johnin Purified Protein Derivative and by Infection withMycobacterium aviumsubsp.paratuberculosisin Experimentally Infected Cattle with Paratuberculosis

Monoclonal antibody neutralization of interleukin-10 (IL-10) increased Johnin purified protein derivative-induced whole-blood gamma interferon (IFN-gamma) secretion 23-fold and also increased IFN-gamma secretion ninefold following in vitro Mycobacterium avium subsp. paratuberculosis infection of peripheral blood mononuclear cells. These results demonstrate the suppressive effect of IL-10 on immune responses to M. avium subsp. paratuberculosis infection in cattle.