Abstract
Leukocyte transendothelial migration into inflamed areas is regulated by the integrity of endothelial cell junctions and is stabilized by adhesion molecules including junctional adhesion molecule-A (JAM-A). JAM-A has been shown to participate in homophilic interactions with itself and in heterophilic interactions with leukocyte function-associated antigen-1 (LFA-1) via its first and second immunoglobulin domains, respectively. Using competitive binding assays in conjunction with atomic force microscopy adhesion measurements, we provide compelling evidence that the second domain of JAM-A stabilizes the homo-philic interaction because its deletion suppresses the dynamic strength of the JAM-A homophilic interaction. Moreover, binding of the LFA-1 inserted domain to the second domain of JAM-A reduces the dynamic strength of the JAM-A homophilic interaction to the level measured with the JAM-A domain 2 deletion mutant. This finding suggests that LFA-1 binding cancels the stabilizing effects of the second immunoglobulin domain of JAM-A. Finally, our atomic force microscopy measurements reveal that the interaction of JAM-A with LFA-1 is stronger than the JAM-A homophilic interaction. Taken together, these results suggest that LFA-1 binding to JAM-A destabilizes the JAM-A homophilic interaction. In turn, the greater strength of the LFA-1/JAM-A complex permits it to support the tension needed to disrupt the JAM-A homophilic interaction, thus allowing transendothelial migration to proceed.
| Original language | English |
|---|---|
| Pages (from-to) | 285-293 |
| Number of pages | 9 |
| Journal | Biophysical Journal |
| Volume | 96 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jan 7 2009 |
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ASJC Scopus subject areas
- Biophysics
Cite this
LFA-1 binding destabilizes the JAM-A homophilic interaction during leukocyte transmigration. / Wojcikiewicz, Ewa P.; Koenen, Rory R.; Fraemohs, Line; Minkiewicz, Julia; Azad, Hashem; Weber, Christian; Moy, Vincent T.
In: Biophysical Journal, Vol. 96, No. 1, 07.01.2009, p. 285-293.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - LFA-1 binding destabilizes the JAM-A homophilic interaction during leukocyte transmigration
AU - Wojcikiewicz, Ewa P.
AU - Koenen, Rory R.
AU - Fraemohs, Line
AU - Minkiewicz, Julia
AU - Azad, Hashem
AU - Weber, Christian
AU - Moy, Vincent T.
PY - 2009/1/7
Y1 - 2009/1/7
N2 - Leukocyte transendothelial migration into inflamed areas is regulated by the integrity of endothelial cell junctions and is stabilized by adhesion molecules including junctional adhesion molecule-A (JAM-A). JAM-A has been shown to participate in homophilic interactions with itself and in heterophilic interactions with leukocyte function-associated antigen-1 (LFA-1) via its first and second immunoglobulin domains, respectively. Using competitive binding assays in conjunction with atomic force microscopy adhesion measurements, we provide compelling evidence that the second domain of JAM-A stabilizes the homo-philic interaction because its deletion suppresses the dynamic strength of the JAM-A homophilic interaction. Moreover, binding of the LFA-1 inserted domain to the second domain of JAM-A reduces the dynamic strength of the JAM-A homophilic interaction to the level measured with the JAM-A domain 2 deletion mutant. This finding suggests that LFA-1 binding cancels the stabilizing effects of the second immunoglobulin domain of JAM-A. Finally, our atomic force microscopy measurements reveal that the interaction of JAM-A with LFA-1 is stronger than the JAM-A homophilic interaction. Taken together, these results suggest that LFA-1 binding to JAM-A destabilizes the JAM-A homophilic interaction. In turn, the greater strength of the LFA-1/JAM-A complex permits it to support the tension needed to disrupt the JAM-A homophilic interaction, thus allowing transendothelial migration to proceed.
AB - Leukocyte transendothelial migration into inflamed areas is regulated by the integrity of endothelial cell junctions and is stabilized by adhesion molecules including junctional adhesion molecule-A (JAM-A). JAM-A has been shown to participate in homophilic interactions with itself and in heterophilic interactions with leukocyte function-associated antigen-1 (LFA-1) via its first and second immunoglobulin domains, respectively. Using competitive binding assays in conjunction with atomic force microscopy adhesion measurements, we provide compelling evidence that the second domain of JAM-A stabilizes the homo-philic interaction because its deletion suppresses the dynamic strength of the JAM-A homophilic interaction. Moreover, binding of the LFA-1 inserted domain to the second domain of JAM-A reduces the dynamic strength of the JAM-A homophilic interaction to the level measured with the JAM-A domain 2 deletion mutant. This finding suggests that LFA-1 binding cancels the stabilizing effects of the second immunoglobulin domain of JAM-A. Finally, our atomic force microscopy measurements reveal that the interaction of JAM-A with LFA-1 is stronger than the JAM-A homophilic interaction. Taken together, these results suggest that LFA-1 binding to JAM-A destabilizes the JAM-A homophilic interaction. In turn, the greater strength of the LFA-1/JAM-A complex permits it to support the tension needed to disrupt the JAM-A homophilic interaction, thus allowing transendothelial migration to proceed.
UR - http://www.scopus.com/inward/record.url?scp=58849161367&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=58849161367&partnerID=8YFLogxK
U2 - 10.1529/biophysj.108.135491
DO - 10.1529/biophysj.108.135491
M3 - Article
C2 - 18849408
AN - SCOPUS:58849161367
VL - 96
SP - 285
EP - 293
JO - Biophysical Journal
JF - Biophysical Journal
SN - 0006-3495
IS - 1
ER -