Study Of Transplantation Of Adrenocortical Cells Using Poly-β-hybroxybutyric Acid As Cell Carrier

Part one: Study of transplantation of adrenocortical cells among allorat using poly-P-hybroxybutyric acid as cell carrierObjective: To investigate the feasibility and possibility of transplantation of adrenocortical cells to therapy insufficiency of adrenocortical function using biodegradable material poly-P-hybroxybutyric acid (PHB) as cell carrier.Methods: Adrenocortical cells from rat adrenal gland were separated and cultured in vitro. The effects of ACTH to the function of basic secretion and stimulating secretion were observed. The immune responses of spleen cell to various adrenal cells were investigated. The effect of PHB to the proliferation and secreting function of adrenocortical cells were evaluated by MTT and RIA method. Then adrenocortical cells were seeded to PHB. After cells were cultured in vitro for about seven days, they were implanted into rats bearing bilateral adrenalectomy. The changes of blood corticosterone and aldosterone were measured. Local histological immunohistochemical ultrastructural changes were studied.Results: Adrenocortical cells from rat adrenal gland can be separated and cultured in vitro. As the cultural time passing by, the aldosterone level decreased and aldosterone level after being stimulated raised (37.01+8.64 u mol/L VS 92.24+42.36 u mol/L, 31.35+7.53 n mol/L VS 142.31+46.12 u mol/L, 13.71+5.76 u mol/L VS 246.84+48.14 u mol/L, P<0.05). The proliferation of adrenal cell was very low comparing to spleen cells and adrenal cells can inhibit the proliferation of immune cells such as spleen cell (0.13+0.02 VS 0.11 +0.03 VS 0.14+0.03 VS 0.52+0.02 VS 0.75+0.01, P<0.05). Adrenocortical cells were able to grow and survive on PHB. No effect to the poliferateion and secreting function of adrenocortical cells was observed. Most bilateral adrenalectomized rats bearing transplantion of adrenocortical cells within PHB (study group) survived longer than those adrenalectomized rats in control group. The blood corticosterone and aldosterone level of study group were higher than that of control group. Histology study showed inflaming cells decreased as time passed, fibrous tisssue disappeared step by step, PHB degraded and blood vessel grow into it. Immunohistochemical study shows transplanted cells stimulate no evident immune response; Ultrastructural study indicates these cells remain animated secreting function.Conclusions: adrenocortical cells from rat adrenal gland can be separated and cultured in vitro. As the cultural time passing by, the basic secreting function of adrenal cells decreased and the stimulating secreting function increased. The immunogenicity of adrenal cells was very low and adrenal cells can inhibit the proliferation of immune cells such as spleen cells. PHB has on effects to the survival, proliferation and secretary function of adrenocortical cells. Adrencortical cells within PHB can survive a period of time. After adrenocortical cells were transplanted into adrenalectomized rats, they can remain animated secreting function and secrete corticosterone and aldosterone which can satisfy the need of adrenalectomized rats. PHB can degrade slowly in vivo. Transplantation of adrenocortical cells using PHB to therapy insufficiency of adrenocortical function has clinlic feasibility and possibility.