RESUMO
The presence of anti-Ro (SS-A) antibody in maternal serum has been associated with congenital heart block. Using human sera monospecific for anti-Ro (SS-A) antibodies in an indirect immunofluorescence assay, Ro (SS-A) antigen was found to be present in the nuclei of myocardial cells and cells of the cardiac conduction system. The possible relationship between the location of Ro (SS-A) antigen, anti-Ro (SS-A) antibody, and heart block is discussed.
Assuntos
Autoantígenos/análise , Coração Fetal/patologia , Bloqueio Cardíaco/imunologia , Sistema de Condução Cardíaco/patologia , RNA Citoplasmático Pequeno , Ribonucleoproteínas , Autoantígenos/imunologia , Colinesterases/metabolismo , Coração Fetal/imunologia , Imunofluorescência , Idade Gestacional , Sistema de Condução Cardíaco/imunologia , Humanos , Soros Imunes/análiseRESUMO
Four hundred fifty-five sera from patients with various connective tissue diseases were screened for the presence of fluorescent antinuclear antibodies (ANA) on two different substrates-mouse kidney sections and WiL-2 cell smears-and precipitin antibodies by using WiL-2 cell extracts as an antigenic source. The antigen for the precipitin was prepared as for extractable nuclear antigen tests. Of 258 sera from systemic lupus erythematosus cases, 73% were positive for ANA on mouse kidney sections, 98% on Wil-2 cell smears, and 47% by precipitin tests. However, 33 sera which were ANA negative on mouse kidney sections were positive on WiL-2 cell smears and also positive for precipitin antibodies. WiL-2 cells used as ANA substrates increased the frequency of ANA in connective tissue diseases, and there was a strong correlation between the WiL-2 cell ANA and the presence of precipitin antibodies. Twenty-four of these 33 sera had anti-SSA/Ro antibody. Some sera containing anti-SSB/La or anti-nRNP antibodies were ANA negative on mouse kidney sections, but all were positive on WiL-2 cells.
Assuntos
Anticorpos Antinucleares/análise , Anticorpos/análise , Doenças do Colágeno/imunologia , Linhagem Celular , Técnicas de Cultura , Imunofluorescência , Humanos , Imunodifusão , PrecipitinasRESUMO
SSA/Ro and SSB/La are soluble cellular proteins to which antibodies are frequently produced in patients with Sjögren's syndrome and systemic lupus erythematosus. In this investigation, we examined anti-SSA/Ro and anti-SSB/La staining patterns on synchronized WiL2 cells and mixed lymphocyte culture cells using monospecific antisera. In addition to its presence in the nucleoplasm, the SSB/La antigen was highly concentrated in the nucleolus of cells during the late G1 and early S phase and is thus cell cycle-related. In contrast, the SSA/Ro antigen was found to be independent of cell cycle, showing a nuclear speckled pattern in all phases. Blocking experiments indicated that free SSB/La is responsible for the nucleolar staining, whereas the combination of both SSA/Ro and SSB/La determines the nucleoplasmic speckled staining pattern.