Limiting Numbers of Mature αβ T Cells Are Required for Complete Donor Chimerism
| Group . | No. of Mice . | Splenic T Cells Added . | (%) Donor T Cells5-150 . | (Mean) . | (%) Donor (H-2b) Cells5-151 . | (Mean) . | |
|---|---|---|---|---|---|---|---|
| . | . | αβ . | γδ . | . | . | . | . |
| I | 2 | None | None | 1, 2 | (2) | 5, 3 | (4) |
| II | 5 | None | 160 × 106 | 74, 69, 83, 82, 82 | (78) | 92, 92, 98, 96, 94 | (94) |
| III | 6 | 2.5 × 104 | None | 4, 3, 1, 1, 1, 3 | (2) | 8, 6, 9, 6, 3, 68 | (17) |
| IV | 6 | 2.5 × 104 | 160 × 104 | 91, 89, 93, 88, 90, 89 | (90) | 99, 98, 99, 98, 98, 98 | (98) |
| Group . | No. of Mice . | Splenic T Cells Added . | (%) Donor T Cells5-150 . | (Mean) . | (%) Donor (H-2b) Cells5-151 . | (Mean) . | |
|---|---|---|---|---|---|---|---|
| . | . | αβ . | γδ . | . | . | . | . |
| I | 2 | None | None | 1, 2 | (2) | 5, 3 | (4) |
| II | 5 | None | 160 × 106 | 74, 69, 83, 82, 82 | (78) | 92, 92, 98, 96, 94 | (94) |
| III | 6 | 2.5 × 104 | None | 4, 3, 1, 1, 1, 3 | (2) | 8, 6, 9, 6, 3, 68 | (17) |
| IV | 6 | 2.5 × 104 | 160 × 104 | 91, 89, 93, 88, 90, 89 | (90) | 99, 98, 99, 98, 98, 98 | (98) |
Irradiated (800 cGy) AKR recipients were transplanted with 10 × 106 TCD B6129 BM marrow cells with or without the indicated number of activated γδ T cells from β 0 donors or naive αβ T cells from δ0 donors. All donor mice were on a B6129 genetic background. Animals transplanted with a total of 160 × 106 γδ T cells received intravenous injections of 80 × 106 cells on the day of transplant and 1 day posttransplant. αβ T cells were obtained by nylon wool depletion of spleen cells from γδ T-cell–deficient (δ0) mice. All mice were analyzed 28 days posttransplant.
Key statistical comparisons: groups II and IV v I, P < .0001; group I v III, P = .54, group II v IV, P = .014.
Groups II and IV v I, P < .001, group I v III, P = .53, group II v IV, P = .03.