Murine monoclonal antibodies to the myelin-associated glycoprotein react with large granular lymphocytes of human blood.

Abstract

Monoclonal antibodies prepared to human myelin-associated glycoprotein were shown to react with a population of human peripheral blood mononuclear cells. The population is similar to the large granular lymphocytes or natural killer cells defined by antibody Leu 7 (also called HNK-1). The population also includes cells exhibiting the Leu 2 marker for suppressor/cytotoxic T cells. The results indicate a shared antigenicity between the nervous system and the immune system and may be relevant to the pathogenesis of demyelinating diseases.Evidence has been accumulating for shared antigenic determinants between the nervous system and the immune system (1-5). This crossreactivity may be involved in the etiopathology of such neurological diseases as multiple sclerosis (5) and myasthenia gravis (3, 4). It recently has been demonstrated that Leu 7 (or HNK-1)-a mouse monoclonal antibody, raised to a human lymphoblastoma, that recognizes human natural killer cells-reacts with components of nervous tissue (6, 7). The myelin-associated glycoprotein (MAG) was identified as a molecule in nervous tissue containing the epitope recognized by this monoclonal antibody (7,8). Furthermore, the epitope in MAG is in its carbohydrate moieties (9) and also is in other glycoconjugates of peripheral nerve (9, 10).In this paper, we describe the reaction of mouse monoclonal antibodies prepared to MAG (11) with a subpopulation of human peripheral blood mononuclear cells. Further experiments show that this population is similar to the large granular lymphocytes (LGL) recognized by Leu 7. The results indicate that MAG and a population of peripheral blood lymphocytes share a common antigenic determinant. This finding may have relevance in the pathogenesis of demyelinating diseases.MATERIALS AND METHODS Monoclonal Antibodies. Murine monoclonal antibodies to MAG were produced as described (11). Briefly, P3X63-Ag8.653 myeloma cells were fused with spleen cells from a female NZB/N mouse immunized with purified human MAG isolated from the central nervous system. Hybrids and subsequent clones were screened for antibody production to MAG by using a solid-phase enzyme immunoassay system. The following monoclonal antibodies were used in this study: G7C8, E8B8, and C6D9 of the IgM subclass with K light chains, which react with determinants in the carbohydrate moieties of human MAG; F7F7, an IgG2b subclass antibody with K light chains, which also reacts with a carbohydrate determinant of human MAG; and B11F7 (IgG2b) and D7E10 (IgGl) with K light chains, which react with polypeptide determinants of human and rat MAG. The hybridomas were grown as ascites tumors in pristane-primed NIH/Swiss nude mice. Monoclonal antibodies were purified from ascites fluid by Sepharose-protein A affinity chromatography (12) for antibodies F7F7 and B11F7 and by euglobulin fractionation followed by Sephadex G-200 chromatography (13) for antibody G7C8. Hybridoma HNK-1 (14) was purchased from the American Type Culture Collection. The hybridoma was grown and the monoclonal a...

Phylogenetically conserved antigen on nerve cells and lymphocytes resembles myelin-associated glycoprotein.

“…Noteworthy in this regard, monoclonal antibodies binding to polypeptide epitopes of the MAG glycoprotein lack immunoreactivity with human mononuclear cells reactive with HNK-1, whereas monoclonal antibodies directed against the sugar moiety of MAG react with the HNK-1+ granular lymphocytes (24). However, we observed that an antiserum reacting with the peptidic moiety of MAG, but that does not detect its HNK-1-defined carbohydrate antigenic determinant, still binds two membrane components from HNK-1+ thymocytes.…”

Myelin‐Associated Glycoprotein Shares an Antigenic Determinant with a Glycoprotein of Human Melanoma Cells

“…The results also demonstrate that the anti-melanoma antibodies (lOC5 and 1 lB5), like HNK-1, belong to a family of monoclonal antibodies that bind to carbohydrate determinants present in MAG, 19-28K-dalton glycoproteins of the PNS, and some sulfated, glucuronic acid-containing sphingoglycolipids of the PNS. A large number of mouse monoclonal antibodies raised in response to human MAG, as well as HNK-1, also react with these glycoconjugates (Ilyas et al, 1984~;Inuzuka et al, 1984;Nobile-Orazio et al, 1984;Dobersen et al, 1985b;OShannessy et al, 1985). In addition, the similarity of the anti-melanoma antibodies with some of the anti-MAG monoclonal antibodies and HNK-1 has been shown by their ability to immunostain the same subset of human lymphocytes with natural killer function as HNK-1 (J. R. Harper, N. M. Varki, P. Minden, P. J.…”

“…In addition, the similarity of the anti-melanoma antibodies with some of the anti-MAG monoclonal antibodies and HNK-1 has been shown by their ability to immunostain the same subset of human lymphocytes with natural killer function as HNK-1 (J. R. Harper, N. M. Varki, P. Minden, P. J. Kelleher, and R. A. Reisfeld, manuscript in preparation;Dobersen et al, 1985~).…”

Anti-myelin-associated glycoprotein antibody in sera from patients with demyelinating diseases

“…4). Recently, it has been reported that mouse monoclonal anti-human MAG antibodies also react with large granular lymphocytes or NK cells of human blood (25). Anti-HNK-1 has been thought to be one of the markers of human natural killer (NK) cells (20).…”