Fundamental Toxicological Sciences

Paper Details

Fundamental Toxicological Sciences
Vol. 5 No. 1 March 07, 2018 p.33-48
Original Article
Subacute toxicity evaluation of KMRC011, a Toll-like receptor-5 agonist administered by intramuscular injection to rats
  • Hong-Soo Lee (Jeonbuk Department of Inhalation Research, Korea Institute of Toxicology, Korea /
  • Jong-Choon Kim (College of Veterinary Medicine, Chonnam National University, Korea /
Min-Sung Kang 1) , Min-Seok Kim 1) , Sung-Hwan Kim 1) 2) , Doin Jeon 1) , Hyeon-Young Kim 1) , Kwang-Hyun Lim 1) , Su-Cheol Han 1) , Kyuhong Lee 1) 2) , Woo-Jong Lee 3) , Chi-Min Choi 3) , Hong-Soo Lee 1) , Jong-Choon Kim 4)
1) Jeonbuk Department of Inhalation Research, Korea Institute of Toxicology, Korea , 2) Department of Human and Environmental Toxicology, University of Science & Technology, Korea , 3) Biomedical Manufacturing Technology Center, Korea Institute of Industrial Technology, Korea , 4) College of Veterinary Medicine, Chonnam National University, Korea
Keywords: KMRC011, Subacute toxicity, Toll-like receptor-5, No-observed-adverse-effect level

The present study investigated the potential subacute toxicity of KMRC011, a Tolllike receptor-5 agonist, by a 4-week repeated intramuscular injection in Sprague-Dawley rats. The test article was administered once daily by intramuscular injection to rats at doses of 0, 0.06, 0.13, and 0.25 mg/kg/day for 4 weeks. At the end of the treatment period, 10 rats/sex/group were sacrificed. The study was continued for the remaining 5 rats/sex in the vehicle control and high dose groups without treatment for 2 weeks (recovery period). During the test period, clinical signs, mortality, body weight, food consumption, ophthalmoscopy, urinalysis, hematology, serum biochemistry, gross findings, organ weight, and histopathology were examined. Hematological investigations revealed a decrease in the hemoglobin, hematocrit, and mean corpuscular hemoglobin values and an increase in the absolute and relative reticulocyte counts. Histopathological evaluation indicated an increase in the incidence of inflammatory cell infiltration in the cecum, lymphocytes infiltration in the duodenum, and hemopoiesis in the femoro-tibial joint/marrow and sternum/marrow in male and female rats. These changes decreased or were no longer observed after the 2-week recovery period, indicating these were reversible changes. Otherwise, no adverse effects were observed in any treatment group. Based on these results, the no-observed-adverse-effect level was considered to be greater than 0.25 mg/kg/day in the rats