Abstract: Objective Previous studies showed that subcutaneous injection of anti-dsDNA antibody idiotypic peptide had the protective effect on autoimmune lupus nephritic mice.Recently,some studies have found that the idiotypic peptide immunization can induce the decrease of specific T cell proliferation and autoantibodies production in animal models.And this may lead us to find a new method to manage the lupus nephritis.The present study intends to explore this kind of protective effect through other route of idiotypic peptide intake.Methods In order to get the lupus nephritic animal model,we invite the GVHD(C57BL/10×DBA/2) F1 mice.For the induction of chronic graft-versus-host disease(GVHD),8-10-week-old(C57B1/10×DBA/2)F1 hybrids were used as recipients,and the donor lymphocytes were from DBA/2 mice.Single-cell suspensions containing a mixture of donor's thymus,spleen,and lymphonode cells were injected intravenously 4 times at 3 to 4 day intervals.The recipient mice develop a variety of pathologic alterations associated with the formation of autoantibodies.A SLE-like disease was evoked,as in human systemic lupus erythematosus,autoantibodies were directly against nuclear antigens.Corresponding to human lupus nephritis,antinuclear antibodies are thought to play a pathologic role in animal renal involvement.For this study,thirtyfive females(C57BL/10×DBA/2) F1 were used for study.Ten of them were in the oral group,fifteen were in the subcutaneous group,and others served as controls.All of them were killed at 24 weeks of age,and body weight,urinary protein,renal histology,and serum IL6 levels were observed.Results After 12 weeks of oral or subcutaneous idiotypic peptide intake,the renal damage was significantly diminished than that in the control mice,and serum IL-6 level were significantly lower.After 10 weeks of idiotypic peptide subcutaneous injection,and after 12 weeks' oral intake,the body weight was significantly higher than that of the control ones.The urinary protein was reduced in subcutanious injection group after 4 weeks treatment,and in oral intake group after 8 weeks' treatment than that in the control ones.Conclusion Oral intake of the anti-dsDNA antibody idiotypic peptide has the same protective effect on lupus nephritis in(C57BL/10×DBA/2) F1 mice as that in subcutaneous injection.

Key words: oral intake idiotypic peptide, body weight, urinary protein, renal histology, IL-6