TNF, interferon-gamma and cell-mediated cytotoxicity in anorexia nervosa; effect of refeeding.

"Natural" cell-mediated cytotoxicity (CMC), spontaneous release of tumor necrosis factor-alpha (TNF-alpha) by mononuclear cells in vitro and PHA-induced interferon-gamma (IFN-gamma) production were examined by standard methods (confirmed by neutralization with monoclonal antibodies) in 14 female patients with marked weight loss due to anorexia nervosa (AN) and 16 matched healthy controls. We found a significant increase in TNF production in AN, as well as a depressed CMC and IFN-gamma production. Following successful refeeding and nutritional rehabilitation of the AN patients, all results normalized to levels similar to those of controls. Thus, undernutrition in AN is accompanied by changes in cytokines and defective "natural" cytotoxicity. The implications in vivo are unclear but our findings may reflect nutritional-related immunodeficiency in AN and moreover, the increased TNF-release may further suppress food intake and enhance tissue catabolism in anorexia nervosa.