Modeling the effects of tetanus vaccination on chronically infected HIV patients

摘要

T-cell activation plays a critical role in the initiation and propagation ofHIV-1 infection and yet transient activation of the immune system is a normalresponse to immunization. In this study we extend a simple of model of HIVinfection to include T cell activation by vaccination. We then show that themodel can reproduce many but not all of the features of the post-tetanusimmunization rise in viral load observed and reported on by Stanley et al., [N.Engl. J. Med., 334:1222--1230 (1996)]. Amplitudes and approximate timing ofpost-immunization maximum viremia were matched in nine of twelve cases; inpatients with double peaks of nearly equal amplitude the later peaks werematched. Patients with single early peaks in their viremia were best fit withrelatively high antigen clearance rate constants, while patients with early andlate peaks in viremia of equal or nearly equal amplitude were best-fit withmuch lower clearance rates. The rate of clearance may depend on the level ofpre-existing antibody, which in turn would be expected to depend on the timesince the individual under study received a previous tetanus vaccination.