title: Immunologic responses in patients with Mycoplasma pneumoniae infections.
abstract: Serum concentrations of IgM and IgG antibodies in patients with Mycoplasma pneumoniae pneumonia were determined by means of the enzyme-linked immunosorbent assay. Analysis of serum specimens by treatment with protein A followed by fractionation on sucrose density gradient revealed for the first time the presence of rheumatoid factor in M. pneumoniae pneumonia with a remarkably high frequency. Development and persistence of the rheumatoid factor during the clinical course of this disease were also examined.
mesh_terms: D000293:Adolescent; D000328:Adult; D000888:Antibodies, Anti-Idiotypic / Q000032:analysis; D002499:Centrifugation, Density Gradient; D002648:Child; D002675:Child, Preschool; D003168:Complement Fixation Tests; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D007075:Immunoglobulin M / Q000276:immunology; D007156:Immunologic Memory; D007223:Infant; D008297:Male; D008875:Middle Aged; D011019:Pneumonia, Mycoplasma / Q000276:immunology*; D012217:Rheumatoid Factor / Q000032:analysis; D013205:Staphylococcal Protein A / Q000494:pharmacology
chemical_list: D000888:Antibodies, Anti-Idiotypic; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D013205:Staphylococcal Protein A; D012217:Rheumatoid Factor