Joseph Merriman

Address: 3-401 BSB
Phone: (319) 335-7817
Email: joseph-merriman@uiowa.edu

Mentor: Patrick M. Schlievert, PhD

Undergraduate Institution: University of Minnesota

Year Entered Into Program: 2012

Research Description

My research focuses on the role of superantigens in chronic wound infections such as surgical site infections. Staphylococcus aureus is the most commonly (25-50%) isolated pathogen from surgical site infections with the most common reservoir (80%) being the patients’ nares. Staphylococcus aureus is capable of producing an array of virulence factors both cell surface associated (MSCRAMMs) and secreted (cytolysins, proteases, and superantigens). As the epidermis is increasingly recognized as not only a physical, but immunological barrier, it is important to understand how highly immuno-stimulatory bacterial products, i.e. superantigens, interact with the epidermis. Previous publications have noted superantigens remarkable capability to stimulate a myriad of human cells, ranging from T-cells, antigen presenting cells, and notably keratinocytes and fibroblasts, all of which play critical roles in the wound healing process. Our lab has previously demonstrated the importance of superantigens in serious diseases such as sepsis, endocarditis, and pneumonia. It is our belief that staphylococcal superantigens are also capable of extending the time to heal wounds through localized and systemic interactions. Through the use of epidemiology, in vitro cell culture, and in vivo models of infection I aim to determine the relative importance of superantigens in chronic skin infections.


Salgado-Pabón W, Herrera A, Vu BG, Stach CS, Merriman JA, Spaulding AR, and Schlievert PM. 2014.Staphylococcus aureus β-toxin Production is Common in Strains with the β-toxin Gene Inactivated by Bacteriophage. J Infect Dis (Epub ahead of print). PMID: 24620023

Merriman JA, and Schlievert PM. 2014. Are we close to a vaccination against Staphylococcus aureus? Future Microbiol 9:717-20. PMID 25046518

Spaulding AR, Salgado-Pabón W, Merriman JA, Stach CS, Ji Y, Gillman AN, Peterson ML, and Schlievert PM. 2014. Vaccination against Staphylococcus aureus pneumonia. J Infect Dis 209:1955-62. PMID: 24357631

van Sorge NM, Cole JN, Kuipers K, Henningham A, Aziz RK, Kasirer-Friede A, Lin L, Berends ET, Davies MR, Dougan G, Zhang F, Dahesh S, Shaw L, Gin J, Cunningham M, Merriman JA, Hütter J, Lepenies B, Rooijakkers SH, Malley R, Walker MJ, Shattil SJ, Schlievert PM, Choudhury B, and Nizet V. 2014. The classical lancefield antigen of group a Streptococcus is a virulence determinant with implications for vaccine design. Cell Host Microbe 11:729-40. PMID: 24922575

Merriman JA, Nemeth KA, and Schlievert PM. 2014. Novel antimicrobial peptides that inhibit gram positive bacterial exotoxin synthesis. PLoS One 9:e95661. PMID: 24748386

Schlievert PM, Merriman JA, Salgado-Pabón W, Mueller EA, Spaulding AR, Vu BG, Chuang-Smith ON, Kohler PL, and Kirby JR. 2013. Menaquinone analogs inhibit growth of bacterial pathogens. Antimicrob Agents Chemother 57:5432-7. PMID: 23959313

Salgado-Pabón W, Breshears L, Spaulding AR, Merriman JA, Stach CS, Horswill AR, Peterson ML, and Schlievert PM. 2013. Superantigens are critical for Staphylococcus aureus Infective endocarditis, sepsis, and acute kidney injury. MBio. 4:e00494-13. PMID: 23963178

Brosnahan AJ, Merriman JA, Salgado-Pabón W, Ford B, and Schlievert PM. 2013. Enterococcus faecalis inhibits superantigen toxic shock syndrome toxin-1-induced interleukin-8 from human vaginal epithelial cells through tetramic acids. PLoS One 8:e61255. PMID: 23613823

Spaulding AR, Lin YC, Merriman JA, Brosnahan AJ, Peterson ML, and Schlievert PM. 2012. Immunity to Staphylococcus aureus secreted proteins protects rabbits from serious illnesses. Vaccine 30:5099-109. PMID: 22691432

Spaulding AR, Satterwhite EA, Lin YC, Chuang-Smith ON, Frank KL, Merriman JA, Schaefers MM, Yarwood JM, Peterson ML, and Schlievert PM. Comparison of Staphylococcus aureus strains for ability to cause infective endocarditis and lethal sepsis in rabbits. Front Cell Infect Microbiol 2:18. PMID: 22919610

Wilson GJ, Seo KS, Cartwright RA, Connelley T, Chuang-Smith ON, Merriman JA, Guinane CM, Park JY, Bohach GA, Schlievert PM, Morrison WI, and Fitzgerald JR. 2011. A novel core genome-encoded superantigen contributes to lethality of community-associated MRSA necrotizing pneumonia. PLoS Pathog 7:e1002271. PMID: 22022262