Randall J. Olsen, M.D., Ph.D.
Clinical Pathology Residency, Baylor College of Medicine, Houston, TX
After completing his fellowship in hematopathology, Dr. Olsen became an Instructor in The Methodist Hospital Research Institute. He was recently awarded a Fellow-to-Faculty transition award from the American Heart Association to investigate virulence genetics in group A Streptococcus. The study will focus on why certain strains are more capable of causing necrotizing fasciitis, or the devastating “flesh eating” disease. He is a member of several professional societies.
The research in Dr. Olsen’s laboratory is focused on studying the molecular pathogenesis of invasive group A Streptococcus (GAS) infections such as necrotizing fasciitis (NF, also termed the “flesh eating infection”). During the past several years, there have been marked advances in the study of GAS genetics and epidemiology, but overall knowledge of the key molecular pathways and host-pathogen interactions mediating GAS virulence in invasive deep soft tissue infections remains largely incomplete. Previous studies in the Musser laboratory suggest that the metal transporter of the Streptococcus regulator (mtsR) regulatory gene and/or the genes under its control (the “mtsR Axis”) may play an important role in GAS NF. Dr. Olsen’s laboratory uses an integrated molecular approach to study the “mtsR Axis” in GAS NF. Affymetrix GAS gene expression microarray analysis, Luminex-based human serum protein profiling, tissue microarray examination, flow cytometric analysis, in vivo molecular imaging, quantitative microbial culture, and in vitro immunologic assays will be used for the detailed study of specimens derived from preclinical models and human patients. The long-term goal is to leverage knowledge gained to aid the development of new diagnostic tools, vaccine strategies, and therapeutic agents that will significantly improve patient care.
Group A Streptococcus, necrotizing fasciitis, invasive infection, pathogen-host interactions, microbial virulence
Fellow-To-Faculty Transition Award, American Heart Association “Role of the mtsR gene in the molecular pathogenesis of group A Streptococcal necrotizing fasciitis”
Long SW, Williams D, Valson C, Cantu CC, Cernoch P, Musser JM, Olsen RJ. A Genomic Day In The Life of a Clinical Microbiology Laboratory. J Clin Microbiol. 2013 Jan 23. PMID: 23345298.
Cagle PT, Olsen RJ. Verifying the Role of Surgical Pathologists in the Precision Medicine of Lung Cancer. Arch Pathol Lab Med. 2012 Dec 31. PMID: 23276149.
Perez KK, Olsen RJ, Musick WL, Cernoch PL, Davis JR, Land GA, Peterson LE, Musser JM. Integrating Rapid Pathogen Identification and Antimicrobial Stewardship Significantly Decreases Hospital Costs. Arch Pathol Lab Med. 2012 Dec 6. PMID: 23216247.
Wimmer JL, Long SW, Cernoch P, Land GA, Davis JR, Musser JM, Olsen RJ. Strategy for Rapid Identification and Antibiotic Susceptibility Testing of Gram-Negative Bacteria Directly Recovered from Positive Blood Cultures using the Bruker MALDI Biotyper and BD Phoenix. J Clin Microbiol. 2012 Jul;50(7):2452-4
Fittipaldi N, Olsen RJ, Beres SB, Van Beneden C, Musser JM. Genomic analysis of emm59 group A Streptococcus invasive strains, United States. Emerg Infect Dis. 2012 Apr;18(4):650-2.
Olsen RJ, Long SW, Musser JM. Bacterial Genomics in Infectious Disease and the Clinical Pathology Laboratory. Arch Pathol Lab Med. 2012 Nov;136(11):1414-22.
Fittipaldi N, Beres SB, Olsen RJ, Kapur V, Shea PR, Watkins ME, Cantu CC, Laucirica DR, Jenkins L, Flores AR, Lovgren M, Ardanuy C, Liñares J, Low DE, Tyrrell GJ, Musser JM. Full-Genome Dissection of an Epidemic of Severe Invasive Disease Caused by a Hypervirulent, Recently Emerged Clone of Group A Streptococcus. Am J Pathol. 2012 Apr;180(4):1522-34.
Olsen RJ, Laucirica DR, Watkins ME, Feske ML, Garcia-Bustillos JR, Vu C, Cantu C, Shelburne SA 3rd, Fittipaldi N, Kumaraswami M, Shea PR, Flores AR, Beres SB, Lovgren M, Tyrrell GJ, Efstratiou A, Low DE, Van Beneden CA, Musser JM. Polymorphisms in regulator of protease B (RopB) alter disease phenotype and strain virulence of serotype M3 group A Streptococcus. J Infect Dis. 2012 Jun;205(11):1719-29.
Shelburne Iii SA, Olsen RJ, Makthal N, Brown NG, Sahasrabhojane P, Watkins EM, Palzkill T, Musser JM, Kumaraswami M. An amino-terminal signal peptide of Vfr protein negatively influences RopB-dependent SpeB expression and attenuates virulence in Streptococcus pyogenes. Mol Microbiol. 2011 Dec;82(6):1481-95.
Horstmann N, Sahasrabhojane P, Suber B, Kumaraswami M, Olsen RJ, Flores A, Musser JM, Brennan RG, Shelburne SA 3rd. Distinct single amino Acid replacements in the control of virulence regulator protein differentially impact streptococcal pathogenesis. PLoS Pathog. 2011 Oct;7(10):e1002311.
Wright AM, Beres SB, Consamus EN, Long SW, Flores AR, Barrios R, Richter GS, Oh SY, Garufi G, Maier H, Drews AL, Stockbauer KE, Cernoch P, Schneewind O, Olsen RJ, Musser JM. Rapidly Progressive, Fatal, Inhalation Anthraxlike Infection in a Human: Case Report, Pathogen Genome Sequencing, Pathology, and Coordinated Response. Arch Pathol Lab Med. 2011 Nov;135(11):1447-59.
Shelburne Iii SA, Sahasrobhajane P, Suber B, Keith DB, Davenport MT, Horstmann N, Kumaraswami M, Olsen RJ, Brennan RG, Musser JM. Niche-specific contribution to streptococcal virulence of a MalR-regulated carbohydrate binding protein. Mol Microbiol. 2011 Jul;81(2):500-14.
Carroll RK, Shelburne SA 3rd, Olsen RJ, Suber B, Sahasrabhojane P, Kumaraswami M, Beres SB, Shea PR, Flores AR, Musser JM. Naturally occurring single amino acid replacements in a regulatory protein alter streptococcal gene expression and virulence in mice. J Clin Invest. 2011 May 2;121(5):1956-68.
Olsen RJ, Watkins ME, Cantu CC, Beres SB, Musser JM. Virulence of serotype M3 group A Streptococcus strains in wax worms (Galleria mellonella larvae). Virulence. 2011 Mar-Apr;2(2):111-9.
Miller AR, Davis GL, Oden ZM, Razavi MR, Fateh A, Ghazanfari M, Abdolrahimi F, Poorazar S, Sakhaie F, Olsen RJ, Bahrmand AR, Pierce MC, Graviss EA, Richards-Kortum R. Portable, battery-operated, low-cost, bright field and fluorescence microscope. PLoS One. 2010 Aug 4;5(8):e11890.
Olsen RJ, Ashraf M, Gonulal VE, Ayeras AA, Cantu C, Shea PR, Carroll RK, Humbird T, Greaver JL, Swain JL, Chang E, Ragasa W, Jenkins L, Lally KP, Blasdel T, Cagle P, Musser JM. Lower respiratory tract infection in cynomolgus macaques (Macaca fascicularis) infected with group A Streptococcus. Microb Pathog. 2010 Dec;49(6):336-47.
Olsen RJ, Sitkiewicz I, Ayeras AA, Gonulal VE, Cantu C, Beres SB, Green NM, Lei B, Humbird T, Greaver J, Chang E, Ragasa WP, Montgomery CA, Cartwright J Jr, McGeer A, Low DE, Whitney AR, Cagle PT, Blasdel TL, DeLeo FR, Musser JM. Decreased necrotizing fasciitis capacity caused by a single nucleotide mutation that alters a multiple gene virulence axis. Proc Natl Acad Sci U S A. 2010 Jan 12;107(2):888-93.
Olsen RJ, Kobayashi SD, Ayeras AA, Ashraf M, Graves SF, Ragasa W, Humbird T, Greaver JL, Cantu C, Swain JL, Jenkins L, Blasdel T, Cagle PT, Gardner DJ, DeLeo FR, Musser JM. Lack of a major role of Staphylococcus aureus Panton-Valentine leukocidin in lower respiratory tract infection in nonhuman primates. Am J Pathol. 2010 Mar;176(3):1346-54.
Olsen RJ, Musser JM. Molecular pathogenesis of necrotizing fasciitis. Annu Rev Pathol. 2010;5:1-31. Review.
Shelburne SA, Olsen RJ, Suber B, Sahasrabhojane P, Sumby P, Brennan RG, Musser JM. A combination of independent transcriptional regulators shapes bacterial virulence gene expression during infection. PLoS Pathog. 2010 Mar 19;6(3):e1000817.
Olsen RJ, Shelburne SA, Musser JM. Molecular mechanisms underlying group A streptococcal pathogenesis. Cell Microbiol. 2009 Jan;11(1):1-12.