Sjögren's syndrome in MRL/l and MRL/n mice

Six autoimmune murine models (MRL/l, MRL/n, NZB, NZB/NZW, PN, C57BL/6J-lpr/lpr) were compared with normal control C57BL/6J and DBA/2 mice to determine if spontaneous autoimmune disease was associated with evidence of Sjögren's syndrome. Schirmer tests documented dry eyes in NZB/NZW and PN mice; other autoimmune strains and controls had normal tear formation. All autoimmune mice had conjunctivitis, but this abnormality was most severe in the PN strain. Ninety-eight percent of MRL/l and MRL/n mice had mononuclear cell infiltrates in lacrimal glands, and salivary glands were involved to a lesser degree. New Zealand mice and PN mice had smaller gland lesions. The extensive gland destruction in MRL/l and MRL/n mice suggested that these substrains merit further studies as animal models of Sjögren's syndrome.