Study on histocompatibility of pinealocyte microencapsules / 中国病理生理杂志

ABSTRACT

AIM: To explore the histocompatibility of pinealocyte microencapsules in vivo. METHODS: The pineal glands of neonatal rats were removed under operating microscope and pinealocytes were isolated through collagenase and trypsin digestion. Pinealocytes were cultured for one week in vitro and collected immediately after digesting was encapsulated in APA microencapsules. The cells and empty capsules were transplanted into abdominal cavity or intermuscular space respectively and retrieved at the 15th or 30th day after operation. Morphological observation, HE staining, cell counting, and HPLC technique were used to analyze the shape, proliferation and function, the degree of inflammation fibrosis of retrieved microencapsules. RESULTS: The retrieve rate of cell capsule from abdominal cavity was about 85 % . The retrieved capsules had integrated profile mostly although some were damaged. The amount of macrophages attached to capsule wall and the thickness of wall increased gradually following the period of transplantation. However, the retrieve rate, wall thickness had no difference between retrieved cell and empty capsules at the same time. Secretion ability of pinealocytes in capsule retrieved at 15th day after operation decreased rapidly and those retrieved at 30th day after operation lossed secretion function. CONCLUSION: APA microencapsules had histocompatibility relatively in vivo and protected pinealocytes in capsule from immunologic rejection of the host. The survival time was about 20 days. During this period cells in capsule maintained activity and MT secretion ability.