Robert Colbert, M.D., Ph.D.
Pediatric Translational Research Branch
The mission of the Pediatric Translational Research Branch (PTRB) is to understand the pathogenesis of chronic inflammation and its impact on structural remodeling of bone in spondyloarthritic diseases such as ankylosing spondylitis. Recent advances from genome wide association studies are beginning to bring genetic susceptibility into focus and suggest that a relatively small number of genes may account for the majority of risk. Fitting the pieces of the complex genetic puzzle together into a cogent pathogenic mechanism for this and other rheumatic diseases remains one of the great challenges in medicine.
While some of the susceptibility genes are envisioned to create a pro-inflammatory diathesis, others are implicated in downstream pathways and may affect responsiveness of cells and tissues to inflammatory mediators and contribute to the unique phenotype. One strategy of the PTRB is to make use of animal models that facilitate molecular dissection of gene function in spondyloarthritis, including the influence of polymorphisms, combined with translational approaches using patient derived material to establish relevance. Recent studies have focused on the role of HLA-B27 in rat spondyloarthritis, resulting in the discovery that this gene product has a tendency to misfold, generating ER stress and activating the unfolded protein response (UPR) particularly when HLA-B27 is upregulated. Novel links between the UPR and inflammatory cytokine production that may drive Th17 activation have also been uncovered. Major projects include: (1) evaluating mechanism and consequences of HLA-B27 misfolding and the UPR on (a) IL-23 production and Th17 activation in rat spondyloarthritis; (b) osteoclast and osteoblast development and function; (2) elucidating genes that influence the development of HLA-B27-associated spondyloarthritis in rats; (3) determining how ERAP1/ARTS1, a newly discovered susceptibility gene, affects disease pathogenesis including functional interactions with HLA-B27 and/or effects on cytokine receptor biology; (4) understanding how susceptibility genes and gene products found to be differentially expressed in spondyloarthritis, modify downstream events in TNF-a-driven sacroiliitis including structural remodeling in post-inflammatory phases of disease. Through these studies we hope to determine how a genotype comprised of relatively common alleles results in a unique disease phenotype, with implications for new treatment strategies.
Before coming to NIAMS, Dr. Colbert served as the director of the Division of Rheumatology at Cincinnati Children's Hospital Medical Center (CCHMC) of the University of Cincinnati College of Medicine (UCCOM). He is certified in pediatric rheumatology by the American Board of Pediatrics and holds memberships in the American Academy of Pediatrics, the American Association of Immunologists, the American College of Rheumatology, the Society for Pediatric Research, and the American Pediatric Society. His research career has included authoring 53 papers and serving as an investigator on a number of NIAMS and other NIH and industry-funded research studies. Dr. Colbert’s accomplishments have been recognized in numerous honors and awards, including Pfizer Postdoctoral Fellowship and Scholar Awards, the James R. Klinenberg Science Award from the Arthritis Foundation, and the American College of Rheumatology’s Deborah Kredich Pediatric Rheumatology Service Award.
- Tran TM, Gill T, Bennett J, Hong S, Holt V, Lindstedt AJ, Bakshi S, Sikora K, Taurog JD, Breban M, Navid F, Colbert RA. Paradoxical Effects of Endoplasmic Reticulum Aminopeptidase 1 Deficiency on HLA-B27 and Its Role as an Epistatic Modifier in Experimental Spondyloarthritis. Arthritis Rheumatol. 2023;75(2):220-231.
- Beck DB, Ferrada MA, Sikora KA, Ombrello AK, Collins JC, Pei W, Balanda N, Ross DL, Ospina Cardona D, Wu Z, Patel B, Manthiram K, Groarke EM, Gutierrez-Rodrigues F, Hoffmann P, Rosenzweig S, Nakabo S, Dillon LW, Hourigan CS, Tsai WL, Gupta S, Carmona-Rivera C, Asmar AJ, Xu L, Oda H, Goodspeed W, Barron KS, Nehrebecky M, Jones A, Laird RS, Deuitch N, Rowczenio D, Rominger E, Wells KV, Lee CR, Wang W, Trick M, Mullikin J, Wigerblad G, Brooks S, Dell'Orso S, Deng Z, Chae JJ, Dulau-Florea A, Malicdan MCV, Novacic D, Colbert RA, Kaplan MJ, Gadina M, Savic S, Lachmann HJ, Abu-Asab M, Solomon BD, Retterer K, Gahl WA, Burgess SM, Aksentijevich I, Young NS, Calvo KR, Werner A, Kastner DL, Grayson PC. Somatic Mutations in UBA1 and Severe Adult-Onset Autoinflammatory Disease. N Engl J Med. 2020;383(27):2628-2638.
- Kim H, Dill S, O'Brien M, Vian L, Li X, Manukyan M, Jain M, Adeojo LW, George J, Perez M, Grom AA, Sutter M, Feldman BM, Yao L, Millwood M, Brundidge A, Pichard DC, Cowen EW, Shi Y, Lu S, Tsai WL, Gadina M, Rider LG, Colbert RA. Janus kinase (JAK) inhibition with baricitinib in refractory juvenile dermatomyositis. Ann Rheum Dis. 2021;80(3):406-408.
- Gill T, Asquith M, Brooks SR, Rosenbaum JT, Colbert RA. Effects of HLA-B27 on Gut Microbiota in Experimental Spondyloarthritis Implicate an Ecological Model of Dysbiosis. Arthritis Rheumatol. 2018;70(4):555-565.
- Gill T, Brooks SR, Rosenbaum JT, Asquith M, Colbert RA. Novel Inter-omic Analysis Reveals Relationships Between Diverse Gut Microbiota and Host Immune Dysregulation in HLA-B27-Induced Experimental Spondyloarthritis. Arthritis Rheumatol. 2019;71(11):1849-1857.
Related Scientific Focus Areas
Genetics and Genomics
Molecular Biology and Biochemistry
This page was last updated on Saturday, September 2, 2023