SAN DIEGO—During the past several decades, an understanding of the pathogenesis of many rheumatic diseases, such as rheumatoid arthritis (RA) and psoriatic arthritis (PsA), has been illuminated by the discovery of the key role played by certain human leukocyte antigen (HLA) alleles. What is now known, according to Robert Winchester, MD, professor of pediatrics, medicine, and pathology in the department of pathology and cell biology, division of rheumatology, at the College of Physicians and Surgeons of Columbia University in New York, is that both RA and PsA are autoimmune in pathogenesis, and that the most important determinants of disease susceptibility are certain alleles encoding the particular major histocompatibility complex, HLA. “While the roles and significance of the HLA genes differ in these two diseases, the HLA molecules encoded by these genes likely contribute importantly to specifying the type of adaptive immune response that underlies each disease,” he said.
What are the implications of this knowledge on understanding the pathogenesis of RA and PsA? Dr. Winchester walked participants through an answer to this question via an elegant lecture on the meaning and significance of HLA associations in rheumatologic diseases during the 2013 Paul Klemperer, MD, Memorial Lecture, “Rheumatoid Arthritis, Psoriatic Arthritis and Autoimmunity: Good Genes, Elegant Mechanisms, Bad Results,” here at the 2013 ACR/ARHP Annual Meeting, held October 26–30. [Editor’s Note: This session was recorded and is available via ACR SessionSelect at www.rheumatology.org/sessionselect.]