TY - JOUR
T1 - Polarized expression of CD74 by gastric epithelial cells
AU - Barrera, Carlos A.
AU - Beswick, Ellen J.
AU - Sierra, Johanna C.
AU - Bland, David
AU - Espejo, Rosario
AU - Mifflin, Randy
AU - Adegboyega, Patrick
AU - Crowe, Sheila E.
AU - Ernst, Peter B.
AU - Reyes, Victor E.
PY - 2005/12
Y1 - 2005/12
N2 - CD74 is known as the major histocompatibility complex (MHC) class II-associated invariant chain (II) that regulates the cell biology and functions of MHC class II molecules. Class II MHC and II expression was believed to be restricted to classical antigen-presenting cells (APC); however, during inflammation, other cell types, including mucosal epithelial cells, have also been reported to express class II MHC molecules. Given the importance of Ii in the biology of class II MHC, we sought to examine the expression of II by gastric epithelial cells (GEC) to determine whether class II MHC molecules in these nonconventional APC cells were under the control of II and to further support the role that these cells may play in local immune and inflammatory responses during Helicobacter pylori infection. Thus we examined the expression of II on GEC from human biopsy samples and then confirmed this observation using independent methods on several GEC lines. The mRNA for II was detected by RT-PCR, and the various protein isoforms were also detected. Interestingly, these cells have a high level expression of surface II, which is polarized to the apical surface. These studies are the first to demonstrate the constitutive expression of II by human GEC.
AB - CD74 is known as the major histocompatibility complex (MHC) class II-associated invariant chain (II) that regulates the cell biology and functions of MHC class II molecules. Class II MHC and II expression was believed to be restricted to classical antigen-presenting cells (APC); however, during inflammation, other cell types, including mucosal epithelial cells, have also been reported to express class II MHC molecules. Given the importance of Ii in the biology of class II MHC, we sought to examine the expression of II by gastric epithelial cells (GEC) to determine whether class II MHC molecules in these nonconventional APC cells were under the control of II and to further support the role that these cells may play in local immune and inflammatory responses during Helicobacter pylori infection. Thus we examined the expression of II on GEC from human biopsy samples and then confirmed this observation using independent methods on several GEC lines. The mRNA for II was detected by RT-PCR, and the various protein isoforms were also detected. Interestingly, these cells have a high level expression of surface II, which is polarized to the apical surface. These studies are the first to demonstrate the constitutive expression of II by human GEC.
KW - Antigen presentation
KW - CD74
KW - Invariant chain
KW - Mucosal immunity
UR - http://www.scopus.com/inward/record.url?scp=28344435788&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=28344435788&partnerID=8YFLogxK
U2 - 10.1369/jhc.4A6552.2005
DO - 10.1369/jhc.4A6552.2005
M3 - Article
C2 - 15923369
AN - SCOPUS:28344435788
SN - 0022-1554
VL - 53
SP - 1481
EP - 1489
JO - Journal of Histochemistry and Cytochemistry
JF - Journal of Histochemistry and Cytochemistry
IS - 12
ER -