Gamma-interferon production in cow milk allergy.

The aim of this study was to develop an assay to assist in the diagnosis of delayed onset of adverse responses to cow milk in children, by measurement of gamma-interferon (GIFN) produced in vitro in response to beta-lactoglobulin-stimulated blood mononuclear cells. Diagnostic procedures identified 75 children with immediate reactions who had high total IgE and IgE-isotype responses to cow milk, 17 children who developed reactions after 24 h and had low total IgE and low IgE-isotype response to cow milk, and 59 milk-tolerant children. GIFN production was less in children with immediate reactions compared to those with late reactions (P < 0.009), or milk-tolerant children (P = 0.022). The results of this study suggest enhanced T-cell reactivity may be involved in the immuno-pathogenesis of non-immediate cow milk allergy, but GIFN production was not a clinically useful diagnostic test.