Increased frequencies of the CD29 and CD57 markers and decreased frequency of CD45RA within CD4+ and CD8+ subsets after allogeneic bone marrow transplantation in man.

Two monoclonal antibodies, anti-CD45RA and anti-CD29, reciprocally divide the CD4+ and CD8+ lymphocytes into CD4+ CD45RA+, CD4+ CD29+, CD8+ CD45RA+ and CD8+ CD29+ subsets. The CD4+ CD45RA+, CD4+ CD29+ and CD8+ CD45RA+ possess suppressor-inducer, helper-inducer and suppressor-effector functions respectively. Since the role of these subsets has not been established after allogenic bone marrow transplantation we studied lymphocyte subpopulations in 12 patients 45-227 days after the procedure. The fraction of CD4+ lymphocytes was significantly (P = 0.0005) decreased to 20 +/- 9% versus 43 +/- 3% in controls. Within the CD4+ compartment, we found an increase in the fraction of CD4+ cells that co-expressed CD29 (CD29+/CD4+) to 92 +/- 10% versus 48 +/- 15% (P = 0.008) in controls and a concomitant decrease in CD45RA+/CD4+ to 16 +/- 12% versus 56 +/- 25% (P = 0.008). Patients were also noted to have an increase in the percentage of CD8+ lymphocytes to 41 +/- 5% compared to 23 +/- 4% in controls (P = 0.0004). Examination of the CD8+ subsets revealed a significant increase in the CD29+/CD8+ fraction to 97 +/- 3% versus 64 +/- 2% in controls (P = 0.008) and a decrease in the CD45RA+/CD8+ fraction to 36 +/- 11% versus 70 +/- 21% (P = 0.008). The number of cells co-expressing CD57 were also determined within the CD4+ and CD8+ subsets. In patients CD57+/CD4+ were increased to 29 +/- 7% versus 1 +/- 1% in controls (P = 0.04), and CD57+/CD8+ to 49 +/- 12% versus 23 +/- 9% (P = 0.02). Since CD29+ and CD57+ cells have a poor capability for IL-2 production and proliferation this shift in subset distribution may account for some of the defects in cellular immunity seen within the first year after allogeneic bone marrow transplantation.