Selective lymphocyte deficiency in seronegative rheumatoid arthritis

Area of Science:

• Immunology
• Virology
• Rheumatology

Background:

• Epstein Barr virus (EBV) is known to induce IgM rheumatoid factor (RF) production in vitro.
• Seropositive rheumatoid arthritis lymphocytes show higher EBV-induced IgM RF production compared to normal lymphocytes.

Purpose of the Study:

• To investigate the in vitro IgM rheumatoid factor production by Epstein Barr virus-infected lymphocytes from seronegative rheumatoid arthritis patients.
• To determine if seronegative rheumatoid arthritis patients have a deficiency in Epstein Barr virus-responsive B cells.

Main Methods:

• In vitro infection of lymphocytes with Epstein Barr virus.
• Quantification of IgM rheumatoid factor production.

Main Results:

• Lymphocytes from seronegative rheumatoid arthritis patients produced significantly less IgM rheumatoid factor after EBV infection compared to normal lymphocytes.
• This indicates a reduced capacity for IgM RF generation in response to EBV in this patient group.

Conclusions:

• Peripheral blood of seronegative rheumatoid arthritis patients may be deficient in Epstein Barr virus-responsive rheumatoid factor precursor B cells.
• This deficiency could contribute to the pathogenesis of seronegative rheumatoid arthritis.