Antigen presentation by B cells leads to a sex-specific immune response in DRB1*0401 mice suggesting a role of B cells and HLA-DR in rendering susceptibility to develop arthritis in females.
However, when stratified by antibiotic response, the frequencies of DRB1 alleles in the 71 patients with antibiotic-refractory arthritis differed significantly from those in the 50 antibiotic-responsive patients (log likelihood test, P = 0.006; exact test, P = 0.008; effect size, Wn = 0.38).
The magnitude of OspA(163-175) binding correlated well with the frequencies of the DRB1 alleles in patients with treatment-resistant arthritis, but the binding of hLFA-1alpha(L330-342) showed only an association with the DRB*04 alleles.
Additionally, persistent disease was predicted by the presence of DRB1*08, and joint erosions were predicted by symmetric arthritis and DRB1*08 and HLA-B27 in combination.
DRB1 alleles encoding a DERAA motif in their third hypervariable region provided a strong dominant protection against RA among DQ5-positive individuals and decreased arthritis activity among DQ3-positive patients.
Using peptide from DRB1*0402 molecule, known to be associated with resistance to RA, prior to induction of collagen induced arthritis prevents the onset of disease.
Co-immunization of the DRB 1*0402 peptide significantly reduced the severity of arthritis (mean score = 1.5+/-0.6 vs 5.2+/-1.4 in controls), whereas multiple doses of the peptide reduced the incidence of disease (3.5% vs 35-60% in controls).
When we try to find a common sequence for all DRB1 alleles involved in juvenile and adult arthritis, we can notice hydrophobic amino acid at position 74, which is present in all these alleles, but not in nonsusceptible alleles, where is the hydrophilic amino acid at position 74.