Tissue distribution of stem cell factor in adults

Abstract

Stem cell factor (SCF) is an essential cytokine during development and is necessary for gametogenesis, hematopoiesis, mast cell development, stem cell function, and melanogenesis. Here, we measure SCF concentration and distribution in adult humans and mice using gene expression analysis, tissue staining, and organ protein lysates. We demonstrate continued SCF expression in many cell types and tissues into adulthood. Tissues with high expression in adult humans included stomach, spleen, kidney, lung, and pancreas. In mice, we found high SCF expression in the esophagus, ovary, uterus, kidney, and small intestine. Future studies may correlate our findings of increased, organ-specific SCF concentrations within adult tissues with increased risk of SCF/CD117-related disease.

Keywords: C-kit; CD117; Immunohistochemistry; Stem cell factor.

Figure 1.. SCF gene expression in human and murine tissues.

(A-B) SCF (KITLG) expression in normal tissues (A) and bone marrow progenitor cells (B) using data mined from the EMBL—European Bioinformatics Institute Gene Expression Atlas and the NIH GenBank. (C) SCF (Kitlg) expression in normal murine tissues based on data mined from the EMBL—European Bioinformatics Institute Gene Expression Atlas.

Figure 2.. Human SCF TMA representative images for both male and female organs.

Immunohistochemistry was performed on the human tissue microarrays, stained for SCF, and analyzed by VisioPharm to compare percent SCF positive cells to total cells within the ROI. From left to right are representative images of the six highest SCF expressing tissues: stomach (a), spleen (b), kidney (c), lung (d), lymph node (e), and pancreas (f). Scale bars are equal to 100 μm.

Figure 3.. Murine SCF tissue expression in TMA and ELISA.

(A) Murine tissue microarrays were stained for SCF and analyzed by VisioPharm. Percent SCF positive cells were compared to total cells within the ROI. Shown from left to right, representative images from the TMA of the six highest expressing tissues: esophagus (a), ovary (b), kidney (c), uterus (d), small intestine (e), and colon (f). Scale bar represents 200 μm. (B-C) An ELISA was performed to obtain SCF concentration in various female (B) and male (C) murine tissues and is shown as mean ± SD (n=4).