Altogether, these data showed that our culture model maintained a diversity of the mTEC subpopulations comparable with that in global thymuses. Open in a separate window Figure 2 Primary cultured human thymic cells display medulla thymic epithelial cell features. and and Values were obtained using the ANOVA test. Asterisks indicate significant differences (**and and thymic expression and 87% of thymic expression were due to the medullary microdissected areas of human thymuses CCK2R Ligand-Linker Conjugates 1 while K8 was mainly cortical (Figure S3 in Supplementary Material). The compared analysis of the gene expressions and their ratios in TEC cultures versus thymic biopsies, confirmed that our culture method sustained the growth of cells expressing predominantly medullary markers such as and agglutinin-1 (UEA) lectin (27, 48, 49), a marker of highly proliferative mTECs expressing autoimmune regulator (AIRE) protein (45). Figure ?Figure22 showed that cultured cells exhibited positive labeling for K5/14, for CLAUDIN 4 (Figures ?(Figures2ACC)2ACC) as compared with thymic biopsies (Figures ?(Figures2DCF).2DCF). These labeling mirrored the medulla compartment of the thymus tissue (Figures ?(Figures2DCF).2DCF). The UEA antibody labeled few cultured mTECs (Figures ?(Figures2GCI).2GCI). Similarly, few mTECs in human thymic sections were stained with this antibody (Figures ?(Figures2JCL).2JCL). The percentage of positive cells in cultured mTECs and in CCK2R Ligand-Linker Conjugates 1 the thymic medullary areas is shown for the different markers in Figure ?Figure2M,2M, and no statistical differences were observed. Altogether, these data showed that our culture model maintained a diversity of the mTEC subpopulations comparable with that in global thymuses. Open in a separate window Figure 2 Primary cultured human thymic cells display medulla thymic epithelial cell features. Representative pictures of a primary cultured human thymic epithelial cells (TECs) (day 7) (ACC) and human thymus (DCF) co-labeled with an anti-Claudin 4 antibody (red), anti-keratin 5, and 14 antibodies (green). Representative pictures of primary cultured human TECs (GCI) and human thymus (JCL) co-labeled with an agglutinin I lectin (UEA) (red), anti-keratin 5 and 14 antibodies (green). The percentage of positive cells in primary cultured human TECs represented the number of KERATIN 5/14, CLAUDIN 4, or UEA positive cells versus the total cell number (M). For thymic sections, the surface of KERATIN 5/14 or CLAUDIN 4 positive areas was measured and compared with the thymic medulla. Images were acquired with a Zeiss Axio Observer Z1 Inverted Microscope using 20 magnification. The counting was done as previously described in Dragin et al. (50). ImageJ software was used to display the digital pictures and to count manually the labeled cells. Graph bar represents the results obtained with four different human biopsies and primary cultured human TECs. The non-parametric MannCWhitney test was used for statistical analyses. Human Primary Cultured mTECs Express Factors Involved in T Cell Negative Selection Process Medulla thymic epithelial cells play a major role in immune tolerance by expressing and presenting TSAs to developing T cells. TSAs expression in mTECs is controlled by various transcription factors among them AIRE, FEZf2, and PRDM1. We CCK2R Ligand-Linker Conjugates 1 evaluated the ability of cultured primary TECs to express such tolerance markers. At day 7, we observed that primary cultured TECs expressed (Figure ?(Figure3A)3A) and various TSAs, such as the -acetylcholine receptor (Values were obtained using the non-parametric MannCWhitney test. Asterisks indicate significant differences (*(Figure ?(Figure4A),4A), tumor growth factor- ((Figure ?(Figure4C),4C), and (Figure ?(Figure4D)4D) compared with the other cell types. Of course, in human thymuses, different cell types may express Values were obtained Rabbit polyclonal to AKAP5 using the MannCWhitney test. Asterisks indicate significant differences (*mRNA expression is CCK2R Ligand-Linker Conjugates 1 regulated by RANK/CD40 and lymphotoxin beta receptor signaling pathways (56C58). We observed a significant increase of AIRE mRNA expression (Figure ?(Figure5A)5A) suggesting that the CCK2R Ligand-Linker Conjugates 1 cultured cells conserved their ability to overexpress.