An analysis by ELISA of 100 rheumatoid factor (RF)-positive sera selected at random from a collection of sera from patients with various auto-immune diseases and joint pains, and 100 RF-negative sera from the same collection matched by patient age and gender, showed that the RF-positive sera had highly significantly (p ≪ 0·0001) raised levels of IgM antibody, but not IgG antibody, to over those of the RF-negative sera. This response was subsequently found to be associated with sera from patients who clinically had rheumatoid arthritis (RA). Sera from the RA patients had significantly greater amounts (p = 0·026) of IgM antibody to than to the other organisms tested and these values were also highly significantly different (p ≪ 0·0001) from IgM antibody levels in matched RF-negative sera. Sera from RA patients also had significantly greater amounts of IgA to (p ≪ 0·0001) and greater amounts of IgM to (p ≪ 0·0001) and (p ≪ 0·0001) than those in matched RF-negative sera. Other classes of antibody to these organisms and all classes of antibody to were not raised in the sera of RA patients over those of RF-negative controls. The IgM response in RA patients was not specific for only one O serotype of but was associated with all 11 different O serotypes of tested and those of other spp. Moreover, the IgM antibodies to spp. appeared to be independent from C-reactive protein and RF. Fourteen of 27 sera from RA patients had an IgM antibody that reacted with an internal 90-kDa protein of . This antibody was not found in RF-positive sera of patients with Sjogren's disease or systemic lupus erythematosus, nor in other RF-negative sera, nor in those of healthy people, nor in those with osteoarthritis or ankylosing spondylitis. IgM antibodies capable of reacting with the haemolysin protein Hpm B of were not found in sera of RA patients of unknown HLA status.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error