Anti-human LFA-1 monoclonal antibodies for prevention of graft failure in HLA-mismatched bone marrow transplantation.

1. 利用抗lfa -1抗体预防hla -单倍型错配骨髓移植（BMT）移植失败。一例范可尼贫血患者由于缺乏相同的供体，接受了T细胞缺失的hla -单倍型不匹配的母体BMT。为了防止移植物失败，使用了针对人LFA-1 α链的小鼠单克隆抗体（mAb）。单抗（25.3）由Immunotech （Marseille, France）提供。对抗体制剂进行无菌性和无热原性检查。单抗以0.1 mg/kg的剂量连续6天（从-3至+6）静脉输注6 h，未见不良反应迹象。部分;血液学重建得以实现，但最终导致移植物失败。范可尼贫血的结果与其他机构的经验一致。然而，在使用抗lfa -1单抗的患者中，没有不良反应鼓励继续进一步的临床研究。抗人LFA-1单克隆抗体的产生。为了获得能够诱导免疫耐受并可供临床使用的抗lfa -1单抗，我们将K4细胞免疫的BALB/C小鼠脾细胞与SP2/0细胞融合。筛选得到的杂交瘤上清液对佛波酯刺激的K4细胞聚集的抑制能力。获得3个分泌抗lfa -1抗体的杂交瘤克隆；一个克隆通过流式细胞术和生化分析获得1链抗体（MAY-035），另外两个克隆获得8链抗体（MAY-017和MAY-044）。所得单抗的同型均为IgGl。这三种抗体强烈抑制淋巴细胞对同种异体抗原和有丝分裂原的增殖。

1. Use of the anti-LFA-1 antibody to prevent graft failure in HLA-haplotype mismatched bone marrow transplantation (BMT). A patient with Fanconi anemia underwent T cell- devpleted HLA-haplotype mismatched maternal BMT because of the lack of HLA-identical donor. To prevent graft failure a murine monoclonal antibody (mAb) directed against the alpha chain of human LFA-1 was used. The mAb (25.3) was kindly supplied by Immunotech (Marseille, France). The antibody preparations were checked for sterility and lack of pyrogenicity. The mAb was given in a 6-h iv infusion m dosis of 0.1 mg/kg for consecutive days from-3 to +6 without any signs of adverse reactions. Partial;hematological reconstitution was achieved but finally resulted in graft failure. The result in Fanconi anemia is in accord with experiences in other institutions. However, no adverse reactions in the use of the anti-LFA-1 mAb encourage to continue further clinical studies in patients selected.2. Production of mAb against human LFA-1. To obtain anti-LFA-1 mAb capable of inducing immune tolerance and available for clinical use spleen cells from BALB/C mice immunized with K4 cells were fused with SP2/0 cells. Hybridoma supernatants obtained were screened for the capability of inhibiting the aggregation of K4 cells stimulated by phorbol ester.Three hybridoma clones secreting anti-LFA-1 antibodies were obtained; one clone was determined by flowcytometry and biochemical analysis to produce the antibody directed at a chain (MAY-035) and other two the antibodies directed at 8 chain (MAY-017, and MAY-044). The isotype of the mAbs obtained was all IgGl. The three antibodies strongly inhibited lymphocyte proliferation in response to alloantigens and mitogens.