naive B cell CD38-negative naive B cell CD38-negative naive B-lymphocyte CD38- naive B-cell CD38-negative naive B-cell CD38- naive B cell CD38- naive B lymphocyte CD38-negative naive B lymphocyte CD38- naive B-lymphocyte A CD38-negative naive B cell is a mature B cell that has the phenotype CD38-negative, surface IgD-positive, surface IgM-positive, and CD27-negative, that has not yet been activated by antigen in the periphery.