Figure 1.
Signalling lymphocyte activation molecule family member 4 (SLAMF4) is a marker of intestinal immune cells. (A) SLAMF4 expression was assessed on haematopoietic-derived (CD45+) cells in the Peyer's patches (PP) and caecal patch (CP) which belong to the gut-associated lymphoid tissue (GALT), mesenteric lymph nodes (MLN), spleen (SPL), peripheral lymph nodes (PLN), as well as other organs as indicated. Bar graph summarises SLAMF4 expression as means of % CD45 cells that are SLAMF4+. (Inset) Dot plots show SLAMF4 expression by CD45+ cells in different tissues. (B) Gut mucosal CD45+ cells express both SLAMF4 and its ligand CD48. Data are presented as means of % SLAMF4+CD45+ cells that are CD48+. Data shown in (A, B) are from ten experiments using two to three mice per experiment for intestinal tissues and four experiments using two to three mice per experiment for other organs. (C) Dot plots show SLAMF4 expression by CD45+ cells in the intraepithelial (IEL) compartment of different segments of the small intestine and colon. Numbers indicate % SLAMF4+CD45+ cells. (D) Murine IEL and lamina propria (LP) fractions were prepared from the small intestine and colon and stained for flow cytometry. Bar graphs show SLAMF4 expression as means of % CD45+ cells that are SLAMF4+ in the IEL compartment versus those in the LP. Data shown in (C, D) are from n=6. (E) SLAMF4 expression was assessed on human small intestine (n=7) and colon (n=10) samples. Dot plots show SLAMF4 expression on human CD45+ cells in the IEL and LP compartments. (F) Data are shown as means of % human CD45+ cells expressing SLAMF4 and (G) relationship between IEL and LP for each tissue sample. Error bars represent SEM. A two-tailed Student's t-test distribution with paired groups of samples was evaluated for statistical significance. A value of p>0.05 is considered not significant (NS); *p<0.05, **p<0.005, ***p<0.005, ****p<0.00005.