Physiological role of macrophage inflammatory protein-3 alpha induction during maturation of intestinal macrophages.
Intestinal macrophages (IMAC) are a central component in the defense of the intestinal mucosa against luminal microbes. In normal mucosa, monocytes differentiate to immunologically tolerant IMAC with a typical phenotype lacking activation markers such as CD14 and TLRs 2 and 4. CD33+ IMAC were isolated from normal intestinal mucosa by immunomagnetic beads. A subtractive hybridization subtracting mRNA from normal IMAC from those of in vitro differentiated macrophages was performed. IMAC differentiation was studied in multicellular spheroids (MCS). Functional assays on migration of CD45R0+ T cells were performed in MCS coculture models. Of 76 clones, 3 obtained by subtractive mRNA hybridization showed >99% homology to mRNA of MIP-3alpha, indicating that this chemokine is induced in IMAC compared with in vitro differentiated macrophages. MIP-3alpha protein expression was confirmed in cryostat sections of normal intestinal mucosa by immunohistochemistry. IMAC in the lamina propria stained positive for MIP-3alpha. FACS of purified IMAC clearly indicated expression of MIP-3alpha in these cells. In the MCS-in vitro differentiation model for IMAC, MIP-3alpha protein expression was absent on day 1 but detectable on day 7 of coculture, demonstrating the induction of MIP-3alpha during differentiation of IMAC. IMAC attracted CD45R0+ T cells to migrate into an MCS coculture model. In human mucosa, a close contact between IMAC and CD45R0+ T cells could be demonstrated. MIP-3alpha is induced during the differentiation of monocytes into IMAC. Our data suggest that MIP-3alpha expression could be involved in the recruitment of CD45R0+ cells into the lamina propria.
Hausmann
Martin
M
Department of Internal Medicine I, University of Regensburg, Regensburg, Germany. martin.hausmann@klinik.uni-regensburg.de
Bataille
Frauke
F
Spoettl
Tanja
T
Schreiter
Katja
K
Falk
Werner
W
Schoelmerich
Juergen
J
Herfarth
Hans
H
Rogler
Gerhard
G
D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000378:metabolism; D015214:Antigens, Differentiation, Myelomonocytic / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology*; D002465:Cell Movement / Q000235:genetics / Q000276:immunology; D002478:Cells, Cultured; D054418:Chemokine CCL20; D019742:Chemokines, CC / Q000096:biosynthesis / Q000502:physiology*; D018920:Coculture Techniques; D003106:Colon / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry; D019073:HT29 Cells; D006801:Humans; D007413:Intestinal Mucosa / Q000166:cytology / Q000276:immunology* / Q000378:metabolism*; D017493:Leukocyte Common Antigens / Q000096:biosynthesis / Q000378:metabolism; D019402:Macrophage Inflammatory Proteins / Q000096:biosynthesis / Q000502:physiology*; D008264:Macrophages / Q000166:cytology / Q000276:immunology* / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009693:Nucleic Acid Hybridization; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018874:Spheroids, Cellular / Q000276:immunology / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D000097382:CD68 Molecule
D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D054418:Chemokine CCL20; D019742:Chemokines, CC; D017493:Leukocyte Common Antigens; D019402:Macrophage Inflammatory Proteins; C108355:CCL20 protein, human; C067980:CD68 antigen, human; D000097382:CD68 Molecule