Figure 1: The Cμ4 domain of IgM binds to human FCMR.
From: Glycan-independent binding and internalization of human IgM to FCMR, its cognate cellular receptor
(a) Mouse BW5147 T cell lines alone (none) or transfected with the retroviral construct containing both human FCMR and GFP cDNAs (FCMR/GFP) were incubated with media alone (isotype control; left panels) or media supplemented with mouse anti-hFCMR mAb (1 μg: middle panels), washed and then labeled with anti-mouse IgG-APC to detect hFCMR expression by flow cytometry. The binding of human IgM (15 μg/ml; right panels) to these cell lines was confirmed. (b) GFP+ hFCMR-transfected cells were incubated with media supplemented with domain-swap Abs (blue trace), hIgM (black trace), or media alone (grey trace) for 1 hr at 4 °C, then washed extensively. Binding of Abs was determined by staining with F(ab’)2-anti lambda-RPE and subsequent flow cytometry analysis. Data are representative of three repeat experiments. Domain swap antibodies have been previously described in detail16,17,18.
