Cholinergic Autoantibodies and Oral Health in HIV+ Patients

Objective: To demonstrate the presence of serum cholinoreceptor autoantibodies, which are related to the stage of the disease evolution, in HIV infected patients. Methods: We evaluated a non random sample of 46 HIV+ adult male patients aged 21-51 years (HIV+/AIDS: 12; HIV+ asymptomatic: 34), at the Clinic for High Risk Patients Care, School of Dentistry, Buenos Aires University. HIV-non infected male individuals (26) aged 21-51 years served as controls. Each patient was clinically examined for oral lesions according to the presumptive criteria of European Community Clearinghouse classification. The CD4+ cell count was determined by flow cytometry and viral load by RT-PCR. Results: The prevalence of different oral disorders was associated with severe immunosuppression and their progressions in the presence of HIV infection were dependent upon the immunologic competence of the host. By ELISA using synthetic peptide corresponding to the aminoacid sequence of the second extracellular loop of human M1 muscarinic acetylcholine receptors (mAChR), we detected that the optical density values and frequency of serum anti M1 mAChR antibodies were higher in HIV+/AIDS patients than HIV+ asymptomatic patients. Sera from HIV- non infected individuals yield negative results. Significant correlation between M1 mAChR autoantibodies titres of each patients and the decrease in CD4+ cells and the increase of viral load was observed. Moreover, the affinity purified anti M1 peptide IgG was able to react with CD8+ T cells triggering the production of large amount of PGE2 from the cells. Conclusion: The antibody-lymphocyte interaction through the release of PGE2, acting as immunomodulator could maintain the immunosuppressive cell response described in AIDS patients.

Grants UBACYT O014, CONICET PIP 5680, Clinical Research Program of the Faculty of Dentistry, University of Buenos Aires (Profesor Rodolfo Erausquin).