Benhamou P Y, Kenmochi T, Miyamoto M, Nakagawa Y, Une S, Stein E, Mullen Y
Department of Surgery, UCLA School of Medicine 90024-7036, USA.
Transplantation. 1995 Jun 27;59(12):1660-5.
We have used the pig as a large animal model for studies of fetal pancreas transplantation. Fetal pig pancreas (FPP) has also been proposed as a potential source of endocrine cells for the treatment of diabetes mellitus. Among the approaches to prevent rejection, the irradiation of donor islets with ultraviolet B light has been used for its immunomodulating properties. Our goal was to study in vitro the effects of UV-B irradiation of FPP on the function and immunogenicity of the tissue. FPP were collagenase-digested and cultured for 1-29 days prior to UV-B irradiation. Static incubation tests were used to measure glucose-theophylline stimulated insulin release. Data obtained at 300 J/m2 revealed no impairment of insulin release (78% to 129% of controls, P = ns). At 500 J/m2, a significant reduction of glucose-theophylline stimulated insulin release was observed with 50-60-day-old FPP (35% to 66% of controls, P < 0.05), but not with 80-day-old FPP (93% of controls, P = ns). At both doses, prolonged observation in culture did not show any alteration of the growth and proliferation of islet cell clusters. UV-irradiated (300 J/m2) adult and fetal pig islet allografts released C-peptide and survived > 200 days. The immunogenicity of irradiated tissues was determined in vitro with allogeneic mixed islet-lymphocyte cultures (MILC). Proliferative responses of allogeneic lymphocytes to UV-irradiated FPP were very significantly decreased by 52-91% at both 300 and 500 J/m2 doses. This effect was observed from 1 to 10 days following UV irradiation and was not modulated by exposure of the tissues to gamma-interferon. We conclude that UVB-irradiation of FPP at a dose of 300 J/m2 does not alter its endocrine function and growth and is effective in reducing tissue immunogenicity. This treatment may be a useful approach for fetal islet transplantation in large animal models.
我们已将猪用作研究胎儿胰腺移植的大型动物模型。胎儿猪胰腺（FPP）也被提议作为治疗糖尿病的内分泌细胞潜在来源。在预防排斥反应的方法中，利用紫外线B光照射供体胰岛的免疫调节特性。我们的目标是在体外研究紫外线B照射FPP对组织功能和免疫原性的影响。在紫外线B照射前，将FPP用胶原酶消化并培养1 - 29天。采用静态孵育试验测量葡萄糖 - 茶碱刺激的胰岛素释放。在300 J/m²获得的数据显示胰岛素释放未受损害（为对照的78%至129%，P = 无显著差异）。在500 J/m²时，观察到50 - 6天龄的FPP葡萄糖 - 茶碱刺激的胰岛素释放显著降低（为对照的35%至66%，P < 0.05），但80天龄的FPP未出现这种情况（为对照的93%，P = 无显著差异）。在这两种剂量下，延长培养观察未显示胰岛细胞簇的生长和增殖有任何改变。紫外线照射（300 J/m²）的成年和胎儿猪胰岛同种异体移植物释放C肽并存活超过200天。用同种异体混合胰岛 - 淋巴细胞培养（MILC）在体外测定照射组织的免疫原性。在300和500 J/m²剂量下，同种异体淋巴细胞对紫外线照射的FPP的增殖反应均非常显著地降低了52% - 91%。在紫外线照射后1至10天观察到这种效应，并且组织暴露于γ - 干扰素并未对其产生调节作用。我们得出结论，以300 J/m²的剂量对FPP进行紫外线B照射不会改变其内分泌功能和生长，并且能有效降低组织免疫原性。这种处理可能是大型动物模型中胎儿胰岛移植的一种有用方法。
