Growth hormone accelerates immune recovery following allogeneic T-cell-depleted bone marrow transplantation in mice.
OBJECTIVE
To test in a murine model whether recombinant human growth hormone can promote immune recovery after allogeneic T-cell-depleted bone marrow transplantation.


METHODS
Lethally irradiated (8.5 Gy) BALB/c mice (H2(d)) were transplanted with 5 x 10(6) T cell-depleted bone marrow cells from C57BL/6 mice (H2(b)). Recipient mice were injected intraperitoneally with recombinant human growth hormone (20 microg/dose/day) or saline for the first 4 weeks after transplantation. These animals were followed for phenotypic and functional immune recovery.


RESULTS
Administration of human recombinant growth hormone improved the CD4(+) T-cell counts in peripheral blood on day +14 (44+/-14 vs 33+/-7/microL blood, p<0.05) and day +21 (281+/-109 vs 187+/-76/microL blood, p<0.01) compared with the saline control. These differences were no longer significant by day +28 despite continued growth hormone administration. Similar effects were also observed on CD8(+) T cells and B220(+) B cells. The improvements in peripheral T-cell counts were at least partially as a result of enhanced thymopoiesis because there was an increase in total thymocytes after treatment with growth hormone. T-cell-depleted bone marrow recipients treated with growth hormone rejected the third-party grafts faster than those treated with saline control (median survival time: 20 days vs 26 days, p<0.05).


CONCLUSIONS
These data demonstrated that recombinant human growth hormone can accelerate phenotypic and functional immune reconstitution following allogeneic T-cell-depleted bone marrow transplantation in mice.
Chen
Benny J
BJ
Departments of Medicine and Immunology, Human Vaccine Institute, Duke University Medical Center, Durham, NC 27705, USA.
Cui
Xiuyu
X
Sempowski
Gregory D
GD
Chao
Nelson J
NJ
D000818:Animals; D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology; D016026:Bone Marrow Transplantation / Q000276:immunology*; D005260:Female; D006084:Graft Rejection; D006086:Graft vs Host Disease / Q000517:prevention & control; D013006:Growth Hormone / Q000494:pharmacology*; D008212:Lymphocyte Depletion; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D014184:Transplantation, Homologous
D013006:Growth Hormone