Generation of monoclonal antibodies specific to mesothelioma

In attemp to develop mesothelioma specific McAb in our laboratory, spleen cells a mouse immunized with isolated tumor cells from a fresh mesothelioma specimen were fused to a drug resistant mouse myeloma cell lines or mesothelioma tumor biopsy tissues. Two monoclonal antibodies, 2A3 and $e1, were identified that bound 6/7 of the mesotheliomas tested, but failed to bind to the majority, 11/13 (for 4E1), of other lung tumors. Based upon western blot analysis of one-and two-dimensional gels and upon the distribution pattern of the antibody-recognized molecule, the 2A3 antibody binds to the cell adhesion molecule CD44. While the specificity of 4E1 has not yet been unequivocally established, it appears to recognize a variant form of the CD44 molecule. Those two monoclonal antibodies are not specific to mesothelioma but useful for differential diagnosis between meosthelioma and other tumors of the lung.