Recovery from immunological paralysis in relation to age and residual antigen

Abstract

Mice paralysed by bovine serum albumin gradually recover immunological reactivity. Recovery has been mapped at various ages by challenge with antigen in Freund's adjuvant, and comparing the resulting antigen binding capacity of the serum with that of normal controls. Recovery proceeds more rapidly in young than in old animals, irrespective of the duration of previous exposure to antigen. This is considered to confirm the importance of cell turnover in recovery. In harmony with this hypothesis, irradiation proved capable of deleting an existing state of paralysis without appreciably enhancing recovery. A cell transfer test has been used to detect antigen in paralysed animals, supplemented by measurement of radioactivity from [¹³¹I]labelled antigen. Antigen can be detected throughout the lag period preceding the start of recovery in quantities probably sufficient to account for the lag.