Serological and immunochemical characterization of « Lutheran-relatedmonoclonal antibodies 9 W 11, 9 W 13, 13 W 1 and 32 W 2

Several examples of so called « Lutheran relatedmonoclonal antibodies have been described. With the exception of one anti-Lu^b [10] they have all shown the same serological reactivity in being weak or negative with the dominant type of Lu(a-b-) cells. Two have the specificity AnWj [5, 3] and others [12, 14] have different, as yet undefined, specificities. By virtue of their positive reactivity with the recessive type of Lu(a-b-) the antigens defined by these antibodies are not thought to be controlled by genes at the Lutheran locus and are not therefore Lutheran system antigens. Their relationship with the Lutheran system remains at the phenotypic level ; the antigens are regulated by a gene, referred to as either In(Lu) or SYN-IB, which also regulates Lutheran and several unrelated antigens on some rare cells — commonly referred to as the dominant type of Lu(a-b-) — referred to throughout this report as Lu(a-b-)d.

The monoclonal antibodies described in this report have been characterised with regard to specificity, thermal and pH optima, ionic strength dependence, enzyme sensitivity and sensitivity to aminoethylisothioronium bromide (AET) and dithiothreitol (DTT). Immunoglobulin class and subclass have been determined and immunoblotting performed with culture supernatants 9 W 11, 9 W 13 and 13 W 1.