Differential molecular and anatomical basis for B cell migration into the peritoneal cavity and omental milky spots.
The constitutive migration of B cells from the circulation into the peritoneal cavity and back is essential for peritoneal B cell homeostasis and function. However, the molecular machinery and the anatomical basis for these migratory processes have hardly been investigated. In this study, we analyze the role of integrins as well as the role of the omentum for B2 cell migration into and out of the peritoneal cavity of mice. We demonstrate that alpha(4)beta(7) integrin-mucosal addressin cell adhesion molecule 1 interaction enables B2 cell migration from the circulation into omental milky spots but not into the peritoneum. In contrast, alpha(4)beta(1) integrin mediates direct entry of B2 cells into the peritoneal cavity as well as their retention at that site, limiting B2 cell egress via the draining parathymic lymph nodes. Surgical removal of the omentum results in a 40% reduced immigration of B2 cells from the circulation into the peritoneum but does not impair B cell exit from this compartment. In conclusion, these data reveal the existence of alternative routes for B2 cell entry into the peritoneal cavity and identify integrins as key factors for peritoneal B2 cell homeostasis, mediating B2 cell migration into and out of the peritoneal cavity as well as their retention at this site.
Berberich
Simon
S
Institute of Immunology, Hannover Medical School, Carl-Neuberg-Strasse 1, Hannover, Germany.
Dähne
Sabrina
S
Schippers
Angela
A
Peters
Thorsten
T
Müller
Werner
W
Kremmer
Elisabeth
E
Förster
Reinhold
R
Pabst
Oliver
O
D000818:Animals; D016175:B-Lymphocyte Subsets / Q000166:cytology* / Q000378:metabolism / Q000637:transplantation; D018821:CD18 Antigens / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology; D002465:Cell Movement / Q000276:immunology*; D006706:Homeostasis / Q000276:immunology; D039441:Integrin alpha4 / Q000502:physiology; D039641:Integrin beta Chains / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology; D019012:Integrin beta1 / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology; D008221:Lymphoid Tissue / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D009852:Omentum / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism; D010529:Peritoneal Cavity / Q000166:cytology* / Q000502:physiology; D013154:Spleen / Q000166:cytology / Q000276:immunology / Q000637:transplantation
D018821:CD18 Antigens; D039641:Integrin beta Chains; D019012:Integrin beta1; C091368:integrin beta7; D039441:Integrin alpha4