The effects of thermal Injury and sepsis on the production of leukocyte microvesicles (INC1P.360)

• Published in: The Journal of immunology (1950) 2015-05, Vol.194 (1_Supplement), p.54-54.17
• Main Authors: Babcock, George, Domenico, Karen, Robinson, Chad
• Format: Article
• Language: English
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.194.Supp.54.17

Microvesicles (MV) are membranous extra cellular vesicles derived from various cells following cell activation or apoptosis. MVs are typically defined as being from 0.1 to 1 µ in size. There have been several reports of biologically active MVs in the blood in certain clinical conditions. The goal of this study was to examine the effects of thermal injury plus sepsis on the number and type of MVs released from leukocytes. C57BL/J mice received 15% total body surface area burn followed by infection with Pseudomonas aeruginosa. At times post injury the blood and bone marrow were examined for MV expressing CD11b, CD19, CD34, CD41, and CD117 using flow cytometry. Generally,the absolute number of MV in the blood dropped following, however, the percentage of the various cell types changed. The percentage of CD11b, 34, and 42 increase slightly following burns but significantly following burn/infection.The absolute numbers of all MV dropped with the exception of CD 19 which increased both in percentage and absolute number in the burn group but not the burned/infected group. The absolute number of CD117+ MV increased significantly in the burn/infected group.The bone marrow remained relative stable with a slight increase in CD117+ MV. These data indicate that the pattern of MVs production changes following burn injury and burn infection. Because the number of CD34+ MV did not increase it would appear that the large increase in CD117+ MV was due to increase in common myeloid progenitors.