Figure 6

Splenic MRC1⁺cells were replenished by monocytes and showed distinct phenotypic changes in chickens with LPS-induced inflammation. A–G PBMCs were isolated from 3-week-old chickens, labelled with CTV, and transferred into age-matched recipient chickens via the intravenous route (200 μL of 1 × 10⁷ cells). To cause LPS-induced inflammation, recipient chickens were intraperitoneally administered 200 μL of LPS (1 mg/kg body weight) or the same volume of PBS (control) immediately after the cell transfer. At 1, 6, and 48 h after LPS administration, spleens were isolated from recipient chickens, and the splenocytes were stained with anti-chicken MRC1 and MHCII antibodies. Injected PBMCs were distinguished from recipient cells (grey dots) by analysing the CTV⁺-pre-gated cells (pink dots). In addition, the MRC1⁺ cells were gated, and the expression of MRC1 and MHCII was examined by flow cytometry for MRC1^loMHCII^hi (solid line) and MRC1^hiMHCII^lo cells (dashed line). Representative dot plot of the results from 1-, 6-, and 48-h post-adoptive transfer A–F showed the proportion of donor MRC1⁺ cells (pink) within the recipient MRC1⁺ populations (grey) in the spleen. The bar graph G represents the proportion of MRC1^loMHCII^hi and MRC1^hiMHCII^lo cells within CTV⁺MRC1⁺ donor cells in the recipient after adoptive transfer (n = 10). H MRC1^loMHCII^hi cells were sorted from the spleen of 3-week-old chickens and labelled with CTV. CTV-labelled MRC1^loMHCII^hi cells were transferred into age-matched recipient chickens via the intravenous route (200 μL of 1 × 10⁷ cells). Then, the recipient chickens were intraperitoneally administered 200 μL of LPS (1 mg/kg body weight). Pink dots represent donor cells, and grey dots recipient cells. The bar graph displays the proportions of MRC1^loMHCII^hi and MRC1^hiMHCII^lo cells within CTV⁺MRC1⁺ cells (pink in the left panel) at 6 h after the cell transfer (n = 6). Data are represented as the mean values ± SD. * P < 0.05, *** P < 0.001.