CD19 and type 1 diabetes mellitus: The basic immunophenotyping findings of the T1DM and SLE groups, when compared to controls, were as follows: a) Increased expression of CD69 molecule in two SLE patients and in one T1DM patient, b) elevated percentage of the CD3+ TCRγδ lymphocyte population (20%) in two SLE patients, c) increased expression of the HLA-DR + cells in 2 of the nine SLE children tested and d) absolute number of B lymphocytes (CD19+) beyond normal values in one SLE and in one T1DM patient.