PT  - JOURNAL ARTICLE
AU  - J Rugtveit
AU  - P Brandtzaeg
AU  - T S Halstensen
AU  - O Fausa
AU  - H Scott
TI  - Increased macrophage subset in inflammatory bowel disease: apparent recruitment from peripheral blood monocytes.
AID  - 10.1136/gut.35.5.669
DP  - 1994 May 01
TA  - Gut
PG  - 669--674
VI  - 35
IP  - 5
4099  - http://gut.bmj.com/content/35/5/669.short
4100  - http://gut.bmj.com/content/35/5/669.full
SO  - Gut1994 May 01; 35
AB  - Mucosal specimens from active Crohn's disease (ileum, n = 6; colon, n = 6), active ulcerative colitis (n = 9), normal ileum (n = 6), and normal colon (n = 6) were subjected to paired immunofluorescence staining for characterisation of macrophage subsets in situ. In the normal state, only few CD68+ macrophages (< 10%) expressing the myelomonocytic L1 antigen (calprotectin) were seen. In inflamed mucosa, especially near small vessels, the CD68+L1+ fraction increased with the degree of inflammation, near ulcers to median 65% (range 35-91%). Cells reactive with the monoclonal antibody RFD7 were also increased in inflammation but less than 5% of them costained for L1 antigen. It is concluded that L1 producing macrophages are distinct from the RFD7+ subset and probably recently recruited from peripheral blood monocytes. Like granulocytes, L1+ macrophages may be important in non-specific defence, providing calprotectin with putative anti-microbial and anti-proliferative properties.