T-cell differentiation in lethally irradiated and reconstituted mice: Functional recovery of PNA-fractionated subpopulations

After lethal irradiation and reconstitution (IR) there is a 6-day lag before thymus cells start to proliferate. In the first 6 days there is a relative enrichment of PNA-negative cells, which are Ly-1⁺ and radioresistant. After IR the mitogenic responses of the PNA-negative cells recover earlier than those of the PNA-positive cells; the implications of this finding for different T-cell lineages are discussed.