Thymus cell traffic induced by antigen stimulation

Spleens of adult mice immunized with either RSA or RGG responded in vitro to DNP-RSA or DNP-RGG, respectively, at a significantly higher rate than spleens of untreated mice. Stimulation in vitro could be achieved by short pulses of the antigen (5–15 min). It was found that thymectomy prior to injection of the carrier protein interfered with the subsequent response in vitro to the hapten-carrier conjugate, and that this was much more pronounced in 8- to 10-day-old mice than in older mice. It is suggested that antigen stimulation in vivo triggers thymus cell migration. Although this is by no means the only mechanism accountable for manifestation of the carrier effect, it may represent a device for amplification of the immune response in vivo.