Comparison of Allogenic and Autogenic Implantations of Dedifferentiated Fat Cells On Monoclonal Antibody 1-22-3-Induced Glomerulonephritis in Rats

Background We established an adipogenic progenitor cell line derived from mature adipocytes and named these cells dedifferentiated fat (DFAT) cells, which have been shown to have characteristics very similar to those of mesenchymal stem cells (MSCs). The potential application of DFAT cells to support cell-based therapies for regenerative and immunosuppressive therapies has been suggested. The present study was designed to address beneficial ways that DFAT implantation can be used clinically as immunosuppressive therapy to treat immunological glomerulonephritis. Methods We evaluated distribution of DFAT cells after intravenous injection through the tail vein in Wistar rats. We examined effects of allogenic implantation of DFAT cells on BrdU incorporation into kidney from rats with monoclonal antibody (mAb) 1-22-3-induced glomerulonephritis. We compared effects of allogenic and autogenic implantations of DFAT cells on excretion of urinary protein, renal function, and glomerular and nephrotubular injuries in these rats, and serum levels of tumor necrosis factor-stimulated gene-6 (TSG-6), and expression of TSG-6 mRNA in kidney. Results The allogenic implantations of DFAT cells trapped in lung improved excretion of urinary protein and renal function, and significantly suppressed glomerular and nephrotubular injuries in the rats with mAb1-22-3-induced glomerulonephritis compared with the autogenic implantations. The allogenic implantation of DFAT cells increased serum levels of TSG-6 especially in mAb 1-22-3-induced glomerulonephritis and significantly increased the expression of TSG-6 mRNA in kidney compared to the autogenic implantation. Conclusion These findings suggest that allogenic implantation of DFAT cells could be clinically useful immunosuppressive therapy for immunological glomerulonephritis.

Ultrastructural Profile Combined with Immunohistochemistry of a Hepatic Progenitor Cell Line in Pediatric Autoimmune Hepatitis: New Insights into the Morphological Pattern of the Disease

Considering that the heterogenic population of a hepatic progenitor cell line (HPCL) can play a vital role in autoimmune hepatitis (AIH), we decided to conduct pioneering retrospective evaluation of these cells in pediatric AIH by means of transmission electron microscopy (TEM). The aim of the study was to assess the ultrastructure of the HPCL in children with untreated AIH. Ultrastructural analysis of the HPCL population, preceded by immunohistochemical staining for cytokeratin 7 (CK7), was performed using pretreatment liver biopsies from 23 children with clinicopathologically diagnosed AIH. Immunohistochemical assessment for CK7 allowed detection of proliferating immature epithelial cells differentiating towards periportal and intralobular intermediate hepatocytes without marked formation of ductular reactions in AIH children. Using TEM, we distinguished three morphological types of HPCs: I—the most undifferentiated progenitor cells; III—intermediate hepatocyte-like cells; II—intermediate bile duct cells. Most frequent were the cells differentiating towards hepatocytes, most rare—those differentiating towards cholangiocytes. The results indicate that an HPCL may be an important source of hepatocyte regeneration. Ultrastructural analyses of the HPCL population, combined with immunohistochemistry for CK7, might be a useful tool to evaluate liver cell regeneration, including fibrogenesis, and may help better understand the morphological pattern of the disease, in pediatric AIH. Frequent appearance of an HPCL in the vicinity of fibrotic foci, often accompanied by hyperactive Kupffer cells and transitional hepatic stellate cells, may indicate their significant involvement in liver fibrogenesis.

Autophagy Is Required for Hepatic Differentiation of Hepatic Progenitor Cells via Wnt Signaling Pathway

The molecular mechanisms regulating differentiation of hepatic progenitor cells (HPCs), which play pivotal roles in liver regeneration and development, remain obscure. Autophagy and Wnt signaling pathways regulate the development and differentiation of stem cells in various organs. However, the roles of autophagy and Wnt signaling pathways in hepatic differentiation of HPCs are not well understood. Here, we describe the effects of autophagy and Wnt signaling pathways during hepatic differentiation of HPCs. We used a well-established rat hepatic progenitor cell line called WB-F344, which was treated with differentiation medium to promote differentiation of WB-F344 cells along the hepatic phenotype. Firstly, autophagy was highly activated in HPCs and gradually decreased during hepatic differentiation of HPCs. Induction of autophagy by rapamycin or starvation suppressed hepatic differentiation of HPCs. Secondly, Wnt3a signaling pathway was downregulated, and Wnt5a signaling pathway was upregulated in hepatic differentiation of HPCs. At last, Wnt3a signaling pathway was enhanced, and Wnt5a signaling pathway was inhibited by activation of autophagy during hepatic differentiation of HPCs. In summary, these results demonstrate that autophagy regulates hepatic differentiation of hepatic progenitor cells through Wnt signaling pathway.

AG424 and AG427 antibodies recognize the human TrkB protein by western blot

The recombinant antibodies AG424 and AG427 detect the human TrkB protein in the human neural progenitor cell line ReNcell® VM and in human brain by western blot.