Roman Dziarski (Polish pronunciation: IPA: /ˈrɔ.man//ˈd͡ʑar.ski/ born December 11, 1949) is a Polish-born American immunologist and microbiologist.

[2] From 1963 to 1967, Dziarski received his secondary education at Reytan High School (Polish: VI Liceum Ogólnokształcące im.

[1][2] From 1973 to 1977, Dziarski was a Research Scientist in the Department of Bacteriology at the National Institute of Public Health (Polish: Narodowy Instytut Zdrowia Publicznego – Państwowy Zakład Higieny), Warsaw, Poland, where he performed research for his Doctor of Philosophy (Ph.D.) degree,[1][2] which culminated in 1977 with the defense of his Ph.D. thesis, titled, Immunobiological properties of Staphylococcus aureus cell wall polysaccharides, with Janusz Jeljaszewicz as his thesis advisor.

[1][2] In 1977, Dziarski joined the Department of Microbiology, Immunology and Pathology at Temple University School of Podiatric Medicine in Philadelphia, Pennsylvania, USA, as a research associate and assistant professor.

[40][41][42][43][44][45][46] Furthermore, Dziarski's and Gupta's groups identified the involvement of several signal transduction molecules and pathways in peptidoglycan-induced cell activation.

[51][52][53] Using similar molecular biology approach the research groups of Carsten J. Kirschning (at Tularik Inc.) and Douglas Golenbock (at Boston University School of Medicine) in collaboration with Dziarski, discovered that TLR2 is the cell-activating receptor for peptidoglycan and other components of Gram-positive bacteria.

In 2001, Dziarski's and Gupta's groups discovered and cloned three human PGRPs, which they named PGRP-L, PGRP-Iα, and PGRP-Iβ (for long and intermediate size transcripts).

[6] They established that the human genome codes for a family of 4 PGRPs: PGRP-S (short PGRP), PGRP-L, PGRP-Iα, and PGRP-Iβ.

[6][60][61] Then, they identified the functions of human PGRPs: PGLYRP2 is a peptidoglycan-lytic enzyme, N-acetylmuramoyl-L-alanine amidase,[63][64] and PGLYRP1, PGLYRP3, and PGLYRP4 are directly bactericidal for both Gram-positive and Gram-negative bacteria.

[65] Collaborative research of Dipika Gupta's and Dziarski's groups also identified and cloned three zebrafish PGRPs and showed that they are highly expressed in eggs, developing embryos, and adult tissues that contact the external environment.

[72] They further showed that these PGRPs have both peptidoglycan-lytic amidase and bactericidal activities and are essential for defense against bacterial infections and survival of the developing zebrafish embryos.

[77] Dziarski's and Gupta's groups further showed that mouse PGRPs play a role in maintaining anti- and pro-inflammatory homeostasis in the intestine, skin, lungs, and joints.

[1] In 1996, Dziarski married Dipika Gupta, a biochemist and molecular biologist at Indiana University School of Medicine.