Identification of two alternatively spliced forms of human tubulointerstitial nephritis antigen (TIN-Ag)

scRNA-Seq of Cultured Human Amniotic Fluid from Fetuses with Spina Bifida Reveals the Origin and Heterogeneity of the Cellular Content

Amniotic fluid has been proposed as an easily available source of cells for numerous applications in regenerative medicine and tissue engineering. The use of amniotic fluid cells in biomedical applications necessitates their unequivocal characterization; however, the exact cellular composition of amniotic fluid and the precise tissue origins of these cells remain largely unclear. Using cells cultured from the human amniotic fluid of fetuses with spina bifida aperta and of a healthy fetus, we performed single-cell RNA sequencing to characterize the tissue origin and marker expression of cultured amniotic fluid cells at the single-cell level. Our analysis revealed nine different cell types of stromal, epithelial and immune cell phenotypes, and from various fetal tissue origins, demonstrating the heterogeneity of the cultured amniotic fluid cell population at a single-cell resolution. It also identified cell types of neural origin in amniotic fluid from fetuses with spina bifida aperta. Our data provide a comprehensive list of markers for the characterization of the various progenitor and terminally differentiated cell types in cultured amniotic fluid. This study highlights the relevance of single-cell analysis approaches for the characterization of amniotic fluid cells in order to harness their full potential in biomedical research and clinical applications.

The Epidemiology behind Pectus Excavatum: Clinical Study and Review of the Literature

INTRODUCTION

 Pectus excavatum (PE) is a funnel-shaped indentation of the sternum and is the most common deformity of the chest wall. It is associated with syndromic diseases but can occur as an isolated form. Familial occurrence is assumed in up to 40% of cases, but large-scale studies are lacking. Most of the data are obtained from case reports which postulate autosomal recessive, dominant with reduced penetrance, X-linked, and multifactorial patterns of inheritance. No monogenetic cause has been identified to date. This study was designed to provide basic information on the epidemiology, family history, and comorbidity for a large cohort of isolated PE and to show that there is an inheritance pattern for PE that indicates a genetic background.

MATERIALS AND METHODS

 A retrospective study was done using a paper-based questionnaire for all PE patients attending two specialized centers for chest wall deformities. Patients with isolated PE were included and asked to provide information on family history and comorbidities.

RESULTS

 Family history was available for 78 patients. A positive family history was found in 42 patients (54%) with a total of 53 affected family members.

CONCLUSION

 The described family histories indicate an underlying genetic cause for PE. Identification of the genetic factors may contribute to characterize patients who are at risk of inheriting isolated PE.

Comprehensive search for cysteine cathepsins in the human genome

Our study was aimed at examinating whether or not the human genome encodes for previously unreported cysteine cathepsins. To this end, we used analyses of the genome sequence and mRNA expression levels. The program TBLASTN was employed to scan the draft sequence of the human genome for the 11 known cysteine cathepsins. The cathepsin-like segments in the genome were inspected, filtered, and annotated. In addition to the known cysteine cathepsins, the scan identified three pseudogenes, closely related to cathepsin L, on chromosome 10, as well as two remote homologs, tubulointerstitial protein antigen and tubulointerstitial protein antigen-related protein. No new members of the family were identified. mRNA expression profiles for 10 known human cysteine cathepsins showed varying expression levels in 46 different human tissues and cell lines. No expression of any of the three cathepsin L-like pseudogenes was found. Based on these results, it is likely that to date all human cysteine cathepsins are known.