[Prevalence of antinuclear envelope antibodies and their isotypes in sera positive for antinuclear antibodies].
Antinuclear antibodies detected in HEp-2 cells by indirect immunofluorescence assay display a great variety of images, including the nuclear envelope pattern. This is quite a less frequent finding. Two thousand five hundred and ninety-four sera were processed, and 37.6% of ANA were detected. The prevalence of anti-nuclear envelope antibodies (ANEA) was of 1.2%, with a high association with autoimmune liver diseases (83%) and a low association with systemic lupus erythematosus. In 21 sera of patients with ANEA, no anti-DNAn antibodies were found; but 28.6% of anti-smooth muscle antibodies and 19% of anti-mitochondrial antibodies were detected. The triple rodent tissue section proved to be a less sensitive substrate than HEp-2 for the detection of ANEA. When using conjugates against different isotypes of antibodies for the detection of ANA, 90.5% of IgG, 66.6% of IgA and 9.5% of IgM. Two patients had ANEA-IgA at high titers (> or = 1:160) without ANEA-IgG. In this work, the importance of performing complementary tests for the detection of anti-smooth muscle antibodies, anti-mitochondrial antibodies and anti-DNAn is highlighted in order to apply these tests as guidelines for the clinical diagnosis of patients with ANEA. Besides, this study expresses the need of using total anti-Ig antibodies as conjugate for IIF-HEp-2 instead of anti-lgG; until the role of IgA antibodies in these autoimmune diseases is clarified.
Arcavi
Miriam
M
Laboratorio de Inmunología Clínica, Departamento de Bioquímica Clínica, Facultad de Farmacia y Bioquímica, Hospital de Clínicas José de San Martín, Universidad de Buenos Aires. arcavimiriam@hotmail.com
Orfus
Gladys
G
D000818:Animals; D000974:Antibodies, Antinuclear / Q000097:blood* / Q000276:immunology; D004847:Epithelial Cells / Q000276:immunology; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007132:Immunoglobulin Isotypes / Q000097:blood* / Q000276:immunology; D023421:Models, Animal; D009685:Nuclear Envelope / Q000276:immunology*; D034881:Nuclear Lamina / Q000276:immunology; D022022:Nuclear Pore / Q000276:immunology; D051381:Rats
D000974:Antibodies, Antinuclear; D007132:Immunoglobulin Isotypes