6th Annual Judith Ramaley Celebration of Research and Creative Scholarship
|
Poster #63 Conditioned Media from Bovine Bronchiole Epithelial Cells Infected with Bovine Herpes Virus Causes a Decrease in Extracellular Trap Formation Kristina Kleinow, Tanya Sands, and Gina Labellarte
Faculty Mentor: Nicole Aulik
Bovine Respiratory Disease (BRD) is the primary cause of morbidity in the U.S. beef and dairy industries. Serious North American economic losses are, reported at between 600 million to 3 billion dollars per year, which leads to a major concern for producers. BRD is caused by viral and bacterial agents that lead to severe pleuropneumonia in cattle, which is characterized by inflammation, intense neutrophil infiltration, fibrin deposition, and consolidation of the lungs. Extensive amounts of extracellular DNA in the lungs of affected cattle have also been detected. One possible source of this DNA is from leukocytes that either die by necrosis or release DNA to form a fibrillar network referred to as extracellular traps (ETs). Previous research by this laboratory has demonstrated that neutrophils and macrophages produce ETs in response to Mannheimia haemolytica and its leukotoxin (LKT). Previous research has demonstrated that media removed from bovine herpes virus (BHV)-infected bovine bronchiole epithelial (BBE) cells contained several cytokines including interferons, IL-1 and IL-6. This conditioned media has been shown to cause an increase in neutrophil migration and diapedesis and enhances neutrophil cell death in response to the M. haemolytica LKT. Therefore, we examine if conditioned media from BBE cells infected with BHV affect ET formation from bovine neutrophils or macrophages. BBE cells were incubated with BHV for various times and conditioned media was removed and stored for further use. 106 bovine were incubated with conditioned media removed at various time points with M. haemolytica cells or its LKT. Similarly, various amounts of M. haemolytica cells or its LKT were incubated with 24 hour conditioned media or control media and ET formation was measured using PicoGreen fluorescence. Our data reveal decrease in ET formation when conditioned media was co-incubated with neutrophils and M. haemolytica cells or LKT in comparison to neutrophils incubated with M. haemolytica cells or LKT and control conditioned media (no BHV infection). Our finding suggest that BHV infection may cause an increase in M. haemolytica- or LKT-induced ET formation by bovine neutrophils, which could lead to an increase in consolidation of the lungs. |
|