Figure 2

Expression of laminin chains in limbal stem/progenitor and associated niche cells in vitro. (A) Phase contrast images of (i) limbal epithelial cell clusters after collagenase digestion, (ii) cultured limbal epithelial progenitor cells, and (iii) associated mesenchymal stromal cells. (B) Quantitative real-time polymerase chain reaction (qRT-PCR) primer assays confirming differential expression of established epithelial (KRT3, KRT15, CEACAM1) and mesenchymal (ICAM1, KIT, SOX2) markers in cultured limbal epithelial progenitor cells (LEPC) compared with cultured limbal mesenchymal stromal cells (LMSC). Data are expressed as means (2^−ΔCT × 1,000) ± SEM (n = 5). (C) Flow cytometry analyses of cultured LMSC showing positive expression of CD44, CD73, CD90, and CD105, but negative expression of CD31, CD34, and CD45. Percentages (%) of positive cells are expressed as means ± SEM (n = 3). (D) qRT-PCR primer assays showing higher expression levels of laminin α3 (LAMA3), α5 (LAMA5), β3 (LAMB3), γ2 (LAMC2) in cultured LEPC, and higher expression levels of laminin α2 (LAMA2), α4 (LAMA4), β2 (LAMB2), γ1 (LAMC1), γ3 (LAMC3) in cultured LMSC; laminin α1 (LAMA1), β1 (LAMB1), and β4 (LAMB4) showed no differential expression patterns. Data are expressed as means (2^−ΔCT × 1,000) ± SEM (n = 5); *p < 0.05; Mann-Whitney U test. (Abbreviations: KRT, Keratin; CEACAM1, carcinoembryonic antigen-related cell adhesion molecule 1; ICAM1, intercellular cell adhesion molecule 1; Sox2, sex determining region Y-box 2; CD, cluster of differentiation).