Production and characterisation of two monoclonal antibodies recognising equine IgG Fc receptors

Despite the importance of IgG Fc receptors in the regulation of various imm unological mechanisms, these receptors have not been well characterised in the domesticated animals including equines. This paper describes the produc tion of two monoclonal antibodies (CVS 59 and CVS 61) that recognise equine IgG Fc receptors. Fusions were conducted using BALB/c mice hyperimmunised with equine peripheral blood mononuclear cells. Hybridoma supernatants were screened on the basis of their ability to inhibit the resetting of equine antibody coated sheep erythrocytes with equine peripheral blood mononuclear cells. The mAbs were then characterised for cellular distribution of the a ntigen by flow cytometry. Using immunoprecipitation, it was shown that both under reducing and non-reducing conditions, CVS 59 and CVS 61 precipitated a 80 and 40 kD protein, respectively. From the functional study coupled wi th cellular distribution and molecular weight of the antigen recognised by these mAbs, it would appear that CVS 59 and CVS 61 recognise an epitope on equine equivalent of human and murine Fc gamma RIII and Fc gamma RII, respe ctively. (C) 2000 Elsevier Science B.V. All rights reserved.