Modulation of regulatory mechanisms operative in the cyclical production of antibody

The response in rabbits to a single intravenous injection of aggregated human gamma globulin (AHuIgG) has been characterized by the successive appearance of peaks of plaque-forming cells (PFC) in the spleen and peripheral blood, separated by well-defined 8-day periods of decreased responsiveness. Although there is evidence in other systems for regulation of the immune response by circulating antibody, resulting in cyclical variations of antibody and PFC, the 8-day latent period in rabbit spleens is observed regardless of the dose of antigen injected or the amount of circulating antibody formed. Thus, it was postulated that if antibody played a role in this system, the antibody produced locally, at the site of PFC production, was the best candidate for exerting such precise control of the response