One B cell culture from Patient 6 was selected for further evaluation since cell culture supernatants were observed to have a higher degree of binding to A-375 and SK-MEL-28 cells compared to melanocytes by ELISA ( Figure 5 , C; right). After limiting dilution of this melanoma-reactive B cell culture, a monoclonal antibody (6_2G3) was further assessed for specificity to 6 melanoma cell lines, melanocytes and fibroblasts by live cell flow cytometry ( Figure 6 ). Since more antibody was available after monoclonal dilution, 2 additional melanoma cell lines along with dermal fibroblasts were evaluated. In concordance with the cellbased ELISA findings ( Figure 5 , C), the 6_2G3 clone bound to a range of melanoma cell lines, but not to melanocytes ( Figure 6 ). The antibody had no reactivity against primary human dermal fibroblasts. In summary, by evaluating the specificity of antibodies to melanoma cells versus melanocytes and fibroblasts we could identify a melanoma-specific monoclonal antibody clone 6_2G3. While we had limited amounts of monoclonal antibodies our B cell culture supernatants after evaluating melanoma-cell specificity, we were able to conduct a limited functional investigation of this antibody.