Jaspreet S. Gujral, M.D., Ph.D.

Dr. Gujral earned his Ph.D. in Interdisciplinary Toxicology from the University of Arkansas for Medical Sciences. His dissertation project involved the study of mechanisms of inflammatory liver injury, especially the role of neutrophils. He has experience with animal models of chemical-induced and inflammatory hepatotoxicity involving both modes of cell death, apoptosis and necrosis, as well as pathological assessment of liver tissues.

After joining Exponent, Dr. Gujral has worked on numerous projects involving the toxicology, mode of action and health effects of hexavalent chromium, such as allergic contact dermatitis and the carcinogenicity of hexavalent chromium. Dr. Gujral has experience in the design and conduct of studies in human volunteers, e.g., to evaluate allergic contact dermatitis from dermal exposures to a pesticide containing hexavalent chromium. He also has experience with institutional review board (IRB) approvals of study protocols, to ensure the ethical conduct of human studies, and the review and approval process of studies by EPA’s Human Studies Review Board (HSRB).

Before coming to the United States for his graduate studies in Toxicology, Dr. Gujral received an M.D. degree from Delhi University in New Delhi, India. He practiced as a physician in Lok Nayak Hospital, New Delhi, where he did his internship and a one-year residency in the management of burn patients.

Wagner M., Zollner G, Fickert P, Gumhold J, Silbert D, Fuchsbichler A, Gujral JS, Zatloukal K, Denk H, Jaeschke H, Trauner M. Hepatobiliary transporter expression in intercellular adhesion molecule 1 knockout and Fas receptor-deficient mice after common bile duct ligation is independent of the degree of inflammation and oxidative stress. Drug Metabolism and Disposition 2007; 35:1694–1699. Epub 2007 Jun 18.

Dorman RB, Gujral JS, Bajt ML, Farhood A, Jaeschke H. Generation and functional significance of CXC chemokines for neutrophil-induced liver injury during endotoxemia. Am J Physiol 2005; 288:G880-G886.

Jaeschke H, Gujral JS, Bajt ML. Apoptosis and necrosis in liver disease (Invited Review). Liver Int 2004; 24:85–89.

Gujral JS, Hinson JA, Jaeschke H. Chlorotyrosine protein adducts are reliable biomarkers of neutrophil-induced cytotoxicity in vivo. Comp Hepatol 2004; 3(Suppl 1):S48.

Gujral JS, Liu J, Farhood A, Jaeschke H. Reduced oncotic necrosis in Fas receptor-deficient C57BL/6J-lpr mice after bile duct ligation. Hepatology 2004; 40:998–1007.

Gujral JS, Liu J, Farhood A, Hinson JA, Jaeschke H. Functional importance of intercellular adhesion molecule-1 in the mechanism of neutrophil-induced liver injury in bile duct-ligated mice. Am J Physiol 2004; 286:G499–G507.

Gujral JS, Hinson JA, Farhood A, Jaeschke H. NADPH oxidase-derived oxidant stress is critical for neutrophil cytotoxicity during endotoxemia. Am J Physiol 2004; 287:G243–G252.

Gujral JS, Farhood A, Bajt ML, Jaeschke H. Neutrophils aggravate acute liver injury during obstructive cholestasis in bile duct-ligated mice. Hepatology 2003; 38:355–363.

Gujral JS, Farhood A, Jaeschke HH. Oncotic necrosis and caspase-dependent apoptosis during galactosamine-induced liver injury in rats. Toxicol Appl Pharmacol 2003; 190:37–46.

Gujral JS, Knight TR, Farhood A, Bajt ML, Jaeschke H. Mode of cell death after acetaminophen overdose in mice: Apoptosis or oncotic necrosis? Toxicol Sci 2002; 67:322-328.

Gujral JS, Bucci TJ, Farhood A, Jaeschke H. Mechanism of cell death during ischemia-reperfusion in rat livers: Apoptosis or necrosis? Hepatology 2001; 33:397–405.

Bajt ML, Lawson JA, Vonderfecht SL, Gujral JS, Jaeschke H. Protection against Fas-receptor-mediated apoptosis in hepatocytes and nonparenchymal cells by a caspase-8 inhibitor in vivo: Evidence for postmitochondrial processing of caspase-8. Toxicol Sci 2000; 58:109–117.

Published Abstracts

Gujral J, Fowler J, Su S, Morgan D, Proctor D. Repeated open application tests for allergic contact dermatitis using two chemicals containing hexavalent chromium. Annual meeting of the Society of Toxicology, Seattle, WA, March 16–20, 2008. The Toxicologist 102(1):317.

Proctor D, Su S, Gujral J, Fowler J, Morgan D. Risk assessment of allergic contact dermatitis due to dermal exposures to hexavalent chromium in environmental and occupational settings. Annual Meeting of the Society of Toxicology, Seattle, WA, March 16–20, 2008. The Toxicologist 102(1): 368.

Gujral JS, Fowler Jr. JF, Su SH, Morgan D, Proctor DM. Repeated open application tests for allergic contact dermatitis due to hexavalent chromium [Cr(VI)]: Risk assessment for dermal contact with Cr(VI). 3rd conference of Occupational and Environmental Exposure of Skin to Chemicals, Golden, CO, June 17–20, 2007.

Proctor DM, Gujral JS, Hong SJ, Gatto NM. Airborne exposures to hexavalent chromium in the chromate production and aerospace industries. 15th Annual Conference of the International Society of Exposure Analysis, Tucson, AZ, October 30–November 3, 2005.

Wagner M, Zollner G, Fickert P, Gumhold J, Silbert D, Fuchsbichler A, Gujral JS, et al. Alterations of hepatobiliary transporter expression in response to common bile duct ligation in mice are independent of ICAM-1 and Fas-receptor expression. Annual Meeting of the European Association for the Study of Liver, Paris, April 13–17, 2005. J. Hepatol. 42 (Suppl. 2):115.

Wagner M, Zollner G, Fickert P, Gumhold J, Silbert D, Fuchsbichler A, Gujral JS, et al. Role of inflammation for hepatobiliary transporter expression in ICAM-/- and lpr mice after common bile duct ligation. Digestive Disease Week and the 106th Annual Meeting of the American Gastroenterological Association, Chicago, IL, May 14-19, 2005. Gastroenterology 128 (4)(Suppl. 2): A89.

Gujral JS, Jaeschke H. Pathophysiological role of selectins in the neutrophil-induced injury phase after bile duct ligation. 12th International Symposium on the Cells of the Hepatic Sinusoid, Bilbao, Spain, 2004.

Gujral JS, Farhood A, Jaeschke H. Neutrophil extravasation and acute liver injury in bile duct-ligated mice is dependent on intercellular adhesion molecule-1 (ICAM-1). Annual Meeting of the American Association for the Study of Liver Diseases, Boston, MA, 2003. Hepatology 38(4) Suppl 1:688A.

Gujral JS, Farhood A, Jaeschke H. Apoptosis and oncotic necrosis during acute liver injury after bile duct ligation in mice. Annual Meeting of the American Association for the Study of Liver Diseases, Boston, MA, 2003. Hepatology 38(4) Suppl 1:240A.

Dorman RB, Gujral JS, Bajt ML, Farhood A, Jaeschke H. Generation and functional importance of CXC chemokines for neutrophil-induced liver injury during endotoxemia in mice. Seminar at the Annual Meeting of the American Association for the Study of Liver Diseases, Boston, MA, 2003. Hepatology 38(4) Suppl 1:249A.

Gujral JS, Farhood A, and Jaeschke H. Galactosamine-induced oncotic necrosis and caspase-dependent apoptosis in rat liver. Annual Meeting of the Society of Toxicology, Salt Lake City, UT, 2003. The Toxicologist: 194.

Gujral J, Farhood A, Bajt ML, Jaeschke H. Neutrophils aggravate cholestatic liver injury in bile duct-ligated animals: Studies with CD18-deficient mice. Annual Meeting of the American Association for the Study of Liver Diseases, Boston, MA, 2002. Hepatology 36(4):331A.

Gujral JS, Farhood A, Jaeschke H. Oncotic necrosis and caspase-dependent apoptosis during galactosamine-induced liver injury in rats. Annual Meeting of the American Association for the Study of Liver Diseases, Boston, MA, 2002. Hepatology 36(4):466A.

Gujral JS, Hinson JA, Jaeschke H. Chlorotyrosine protein adducts are reliable biomarkers of neutrophil cytotoxicity in the liver in vivo. 11th International Symposium on the Cells of the Hepatic Sinusoid, Tucson, AZ, 2002.

Jaeschke H, Gujral JS. Liver ischemia-reperfusion injury: Role of apoptotic cell death? International Conference on Transplantation, Nagoya, Japan, 2001.

Gujral JS, Knight TR, Farhood A, Jaeschke H. Mechanism of cell death after acetaminophen overdose: Apoptosis or necrosis? Annual Meeting of the Society of Toxicology, San Francisco, CA, 2001. Toxicologist 60(1):351.

Gujral JS, Bucci TJ, Farhood A, Jaeschke H. Mechanism of cell death during ischemia-reperfusion in rat livers: Apoptosis or necrosis? Annual Meeting of the American Association for the Study of Liver Diseases, Dallas, TX, 2000. Hepatology 32(4):249A.

Bajt ML, Gujral JS, Lawson JA, Vonderfecht SL, Jaeschke H. Postmitochondrial processing of caspase-8 amplifies the activation of the caspase cascade during Fas-receptor-mediated apoptosis in the liver. Shock 2000; 13(supplement 1):114.

Technical Reports

Proctor DM, Gujral J, Su S, Fowler Jr. JF. Repeated open application test for allergic contact dermatitis due to hexavalent chromium [Cr(VI)] as CopperShield®: Risk assessment for dermal contact with Cr(VI). FPRL #012506. Environmental Protection Agency, Washington, DC, July 2006.

Proctor DM, Gujral J, Su S, Fowler Jr. JF. Repeated open application test for allergic contact dermatitis due to hexavalent chromium [Cr(VI)] as potassium dichromate: Risk assessment for dermal contact with Cr(VI). FPRL #012406. Environmental Protection Agency, Washington, DC, September 2006.

Presentations

Gujral JS. Role of neutrophils in liver injury induced by obstructive cholestasis in bile duct-ligated mice. Dissertation Defense, Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR, 2004.

Gujral JS. Generation and functional importance of CXC chemokines for neutrophil-induced liver injury during endotoxemia in mice. The Annual Meeting of the American Association for the Study of Liver Diseases, Boston, MA, 2003.

Gujral JS. Neutrophils aggravate liver injury during obstructive cholestasis in bile duct-ligated mice. The Seager Braswell Student Research Symposium, Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR, 2003.

Gujral JS. Galactosamine-induced liver injury in rats consists of oncotic necrosis and caspase-dependent apoptosis. The Seager Braswell Student Research Symposium, Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR, 2002.

Gujral JS. Mechanism of cell death during ischemia-reperfusion in rat livers: Apoptosis or necrosis? The Seager Braswell Student Research Symposium, Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR, 2001.

• Graduate Assistant, Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, 1999–2004
• Junior Resident, Department of Burns and Plastic Surgery, Lok Nayak Hospital, New Delhi, India, 1998
• Medical Intern, Lok Nayak Hospital, New Delhi, India, 1997
  

Designed and conducted studies in human volunteers to evaluate allergic contact dermatitis from dermal exposures to chemicals containing hexavalent chromium. Protocol was reviewed by an institutional review board (IRB) to ensure the fulfillment of ethical requirements for human subject studies. Dose-response data were analyzed using EPA benchmark dose software to determine the minimum elicitation threshold (MET 10%) for these chemicals. Study reports were submitted to EPA’s Office of Pesticide Programs for consideration in its dermal risk assessments for community exposures to treated wood and for environmental exposures, such as deriving soil cleanup criteria. Studies were also reviewed by the Human Studies Review Board (HSRB) and were approved for use by the EPA.

Designed and conducted studies in human subjects to evaluate the extent of water adherence to the skin under various exposure conditions. Protocol was approved by the institutional review board (IRB). Information gathered from these studies was helpful in estimating exposures to accidental splashes or transient immersion in contaminated water or aqueous solutions of chemicals.
Provided comments on the newly proposed soil remediation standards by the New Jersey Department of Environmental Protection (NJDEP).

Prepared comments to the National Toxicology Program (NTP) on its findings from chronic animal studies with hexavalent chromium in drinking water.

Provided litigation support on a case involving health effects, such as asbestosis, mesothelioma and lung cancer, in the plaintiffs due to suspected exposures to asbestos.

Reviewed ATSDR’s health consultations and health statistics reviews on vermiculite exfoliation plants that received contaminated vermiculite from Libby, Montana. These health consultations described occupational and community exposures to vermiculite ore, exfoliated vermiculite product, and asbestos-contaminated waste. They were published by ATSDR under its National Asbestos Exposure Review (NAER) program.

Provided litigation support in a case involving suspected hexavalent chromium emissions from cooling towers at rocket engine testing facilities and suspected hexavalent chromium-induced cancers.

Reviewed epidemiological studies for hexavalent chromium, evaluated the utility of biomonitoring, and the concept of threshold for lung carcinogenicity relating to hexavalent chromium. Assisted in the preparation of comments to OSHA regarding its new proposed PEL for hexavalent chromium.

Conducted an electron microscopy study to evaluate particle size of residue from the historical chromate production industry. The data from this study was included in our comments to OSHA regarding a new proposed PEL for hexavalent chromium.

Conducted searches of ATSDR’s Public Health Assessments to evaluate the criteria for setting up medical monitoring programs.

Evaluated the occurrence of chromium and other metals at tannery sites and sludge disposal areas through review of historical literature, EPA’s Records of Decision and ATSDR’s Public Health Assessments.

Reviewed findings of animal studies on chromium-induced toxicity by the oral route conducted by the National Toxicology Program and other groups, and prepared an assessment of liver toxicity due to chromium, and whether the effects observed in the liver can be used as early indicators of liver toxicity.

• Society of Toxicology