TY - JOUR
T1 - Recombinant expression of bovine LFA-1 and characterization of its role as a receptor for Mannheimia haemolytica leukotoxin
AU - Dileepan, Thamotharampillai
AU - Thumbikat, Praveen
AU - Walcheck, Bruce
AU - Kannan, Mathur S.
AU - Maheswaran, Samuel K.
N1 - Funding Information:
This work was supported by USDA-NRI competitive grant # 35204-9230, and Minnesota Agricultural Experimental Station grant.
Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2005/5
Y1 - 2005/5
N2 - Mannheimia (Pasteurella) haemolytica leukotoxin (LktA) is the primary virulence factor contributing to the pathogenesis of lung injury in bovine pneumonic mannheimiosis (BPM), a disease which causes major economic loss to the US cattle industry annually. Recent work from our laboratory using an antibody-based approach has shown that LktA binds to bovine LFA-1 in target cells. While this study suggests that LFA-1 might be a specific receptor, it remains to be conclusively shown that LFA-1 is sufficient to induce susceptibility to LktA. It was of interest to determine if functionally active bovine LFA-1 could be reconstituted on a LFA-1 negative cell line and reconstitute susceptibility to LktA. Here, we report the successful recombinant expression of bovine LFA-1 on the cell surface of the human erythroleukemic K562 cell line. The BoLFA-1 transductant expresses bovine CD18 and CD11a as a heterodimer. We found that LktA binds to both the CD18 and CD11a subunits of BoLFA-1 cells. Exposure of BoLFA-1 cells to LktA, induced tyrosine phosphorylation of the CD18 tail, elevation of intracellular calcium, and cytolysis. This is the first report on recombinant expression of functionally active bovine LFA-1 by transduction into an LktA-non-susceptible human cell line.
AB - Mannheimia (Pasteurella) haemolytica leukotoxin (LktA) is the primary virulence factor contributing to the pathogenesis of lung injury in bovine pneumonic mannheimiosis (BPM), a disease which causes major economic loss to the US cattle industry annually. Recent work from our laboratory using an antibody-based approach has shown that LktA binds to bovine LFA-1 in target cells. While this study suggests that LFA-1 might be a specific receptor, it remains to be conclusively shown that LFA-1 is sufficient to induce susceptibility to LktA. It was of interest to determine if functionally active bovine LFA-1 could be reconstituted on a LFA-1 negative cell line and reconstitute susceptibility to LktA. Here, we report the successful recombinant expression of bovine LFA-1 on the cell surface of the human erythroleukemic K562 cell line. The BoLFA-1 transductant expresses bovine CD18 and CD11a as a heterodimer. We found that LktA binds to both the CD18 and CD11a subunits of BoLFA-1 cells. Exposure of BoLFA-1 cells to LktA, induced tyrosine phosphorylation of the CD18 tail, elevation of intracellular calcium, and cytolysis. This is the first report on recombinant expression of functionally active bovine LFA-1 by transduction into an LktA-non-susceptible human cell line.
KW - Bovine LFA-1
KW - Leukotoxin
KW - Mannhemia haemolytica
KW - Transductant
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U2 - 10.1016/j.micpath.2005.02.005
DO - 10.1016/j.micpath.2005.02.005
M3 - Article
C2 - 15925274
AN - SCOPUS:19544363788
SN - 0882-4010
VL - 38
SP - 249
EP - 257
JO - Microbial Pathogenesis
JF - Microbial Pathogenesis
IS - 5-6
ER -