Marin M L, Hardy M A, Gordon R E, Reemtsma K, Benvenisty A I
Department of Surgery, Columbia University College of Physicians and Surgeons, New York, NY 10032.
J Vasc Surg. 1990 Jan;11(1):103-11.
Prosthetic grafts of vein allografts are inadequate as small-diameter vessel substitutes. We have applied ultraviolet B (UVB) irradiation to modulate the immunogenicity of vein allografts to avoid immunologic injury. The veins of male ACI rats were irradiated with UVB (60 mJ/cm2) in situ and transplanted to male ACI rats (autografts) and female Lewis rats (allografts). Nonirradiated veins served as controls. At 4, 7, 14, and 28 days, all grafts were patent and were studied for morphologic changes by scanning electron microscopy and for immunogold labeling of major histocompatibility complex class II antigen expression. In autografts, scanning electron microscopy demonstrated minimal endothelial loss after grafting, regardless of UVB irradiation. Untreated allografts showed severe endothelial injury 4, 7, and 14 days after transplantation. UVB irradiation of veins protected allografts from injury to the endothelium and basement membrane. Major histocompatibility complex class II-positive endothelial cells were not seen in autografts but were seen in 40% of cells 4 days after transplantation in untreated allografts. UVB-treated allografts showed MHC class II antigen expression labeling of 20% of the endothelial cells. Barr body analysis demonstrated the donor origin of these endothelial cells. UVB irradiation of rat vein allografts prolongs endothelial survival while decreasing endothelial surface expression of class II antigens. These data suggest that modification of vein immunogenicity with UVB irradiation may permit functional survival of small-vessel allografts without chronic immunosuppression.
静脉同种异体移植物的人工血管作为小口径血管替代物并不理想。我们应用紫外线B（UVB）照射来调节静脉同种异体移植物的免疫原性，以避免免疫损伤。将雄性ACI大鼠的静脉原位照射UVB（60 mJ/cm²），然后移植到雄性ACI大鼠（自体移植）和雌性Lewis大鼠（同种异体移植）体内。未照射的静脉作为对照。在第4、7、14和28天，所有移植物均保持通畅，并通过扫描电子显微镜研究其形态学变化，以及通过免疫金标记研究主要组织相容性复合体II类抗原的表达。在自体移植中，无论是否进行UVB照射，扫描电子显微镜显示移植后内皮损失最小。未处理的同种异体移植在移植后4、7和14天显示出严重的内皮损伤。静脉的UVB照射可保护同种异体移植免受内皮和基底膜损伤。在自体移植中未见主要组织相容性复合体II类阳性内皮细胞，但在未处理的同种异体移植中，移植后4天可见40%的细胞中有此类细胞。经UVB处理的同种异体移植显示20%的内皮细胞有MHC II类抗原表达标记。巴氏小体分析证实了这些内皮细胞的供体来源。大鼠静脉同种异体移植的UVB照射可延长内皮存活时间，同时降低II类抗原的内皮表面表达。这些数据表明，用UVB照射改变静脉免疫原性可能允许小血管同种异体移植在无慢性免疫抑制的情况下功能存活。
