- Beta 2-microglobulin-deficient mice are protected from hypergammaglobulinemia and have defective antibody responses because of increased IgG catabolism. Christianson, G.J., Brooks, W., Vekasi, S., Manolfi, E.A., Niles, J., Roopenian, S.L., Roths, J.B., Rothlein, R., Roopenian, D.C. J. Immunol. (1997)