Journal: bioRxiv
Article Title: Myeloid-Derived Suppressor Cells are relevant factors to predict the severity of multiple sclerosis
doi: 10.1101/2022.04.20.488896
Figure Lengend Snippet: A-C: CD14 + cells showed different levels of HLA-DR in demyelinating lesions. Based on the intensity of HLA-DR (á′, b′′, ć′) we identified two cell subpopulations: CD14 + HLA-DR -/low cells were considered as M-MDSC-like cells ( A , B ) and CD14 + HLA-DR hi cells were identified as putative inflammatory macrophages ( C ). The lack of CD15 expression in CD14 + cells (á′′, b′′′, ć′′) corroborated the exclusive presence of M-MDSC-like cells in MS lesions. D - G : Both CD14 + cell subpopulations were stained for CD11b, confirming their myeloid cell nature. Arrowheads point to myeloid cells with M-MDSC phenotype, i.e CD14 + CD11b + HLA-DR low , while arrows indicate CD11b + inflammatory macrophages. H - O : TMEM119 + cells with microglial morphology were detected in the NAWM ( H - K ). The lack of TMEM119 immunoreactivity observed in amoeboid CD14 + HLA-DR -/low M-MDSC-like cells (pointed by arrows on L-O) confirmed the peripheral origin of these cells. Yellow and white arrowheads in L-O point to inflammatory monocyte-derived macrophages (CD14 + HLA-DR hi ) and microglial-derived macrophages (CD14 - HLA-DR hi ), respectively. P : Quantification of the density of putative M-MDSC in all MS lesion types from SPMS and PPMS patients. The abundance of CD14 + CD15 - HLA-DR -/low cells was significantly higher in the AL and in the rAIL (n=46 AL, 27 AIL and 24 IL from 33 MS patients). Q: AL and the rAIL from SPMS and PPMS patients showing a greater presence of M-MDSC-like cells than in cAIL and IL (n = 24 AL, 14 AIL and 14 IL from 20 SPMS patients; 22AL, 12 AIL and 10 IL from 13 PPMS patients). Scale bar: A-C = 5 µm; insets in A-C = 10 µm; D-G = 40 µm; H-K = 20 µm; L-O = 37 µm. Comparative analyses were carried out with ANOVA and the mean + SEM data are shown: *, # p < 0.05. In Q, * represents the difference with respect to AL and # with respect to the rAIL. rAIL, rim of AIL; cAIL, center of AIL; High. Inf Area, high inflammatory area; Weak Inf Area, weak inflammatory area.
Article Snippet: Subsequently, immunohistochemistry (IHC) or immunofluorescence (IF) staining was performed by incubating sections overnight at 4°C with the following primary antibodies: rabbit anti-CD11b (1:100; Abcam, ab133357); rabbit anti-TMEM119 (1:50; Sigma-Aldrich, HPA0518870); biotinylated sheep anti-CD14 (1:25; R&D, BAF383), mouse anti-CD15 (1:25; Agilent, ISO62, carb-3 clone) and mouse anti-human leukocyte antigen (HLA)-DR (1:200 for IHC, 1:100 for IF; Agilent, M0746, TAL.1B5 clone).
Techniques: Expressing, Staining, Derivative Assay