Kappa and lambda receptor sites on single lymphocytes.
Light chain receptors on human circulating lymphocytes of thirty-three normal individuals were visualized by the immunocyto-adhesion reaction in which human (anuclear) erythrocytes coated with κ chains and chicken (nucleated) erythrocytes coated with λ chains (or vice versa) were used. 4·4 (±2·3)% of the lymphocytes had κ and 4·15 (±2·4)% had λ receptors, when the lymphocytes were sensitized with antisera to either κ and λ chains. When both antisera were used simultaneously only 5·3 (±3)% were found to have receptors and the majority of cells carried both κ and λ receptors. These findings suggest that in these cells the genes for the constant regions of both light chains are active.