Mouse and human studies support DSTYK loss of function as a low-penetrance and variable expressivity risk factor for congenital urinary tract anomalies.

PURPOSE: Previous work identified rare variants in DSTYK associated with human congenital anomalies of the kidney and urinary tract (CAKUT). Here, we present a series of mouse and human studies to clarify the association, penetrance, and expressivity of DSTYK variants. METHODS: We phenotypically characterized Dstyk knockout mice of 3 separate inbred backgrounds and re-analyzed the original family segregating the DSTYK c.654+1G>A splice-site variant (referred to as "SSV" below). DSTYK loss of function (LOF) and SSVs were annotated in individuals with CAKUT, epilepsy, or amyotrophic lateral sclerosis vs controls. A phenome-wide association study analysis was also performed using United Kingdom Biobank (UKBB) data. RESULTS: Results demonstrate ∼20% to 25% penetrance of obstructive uropathy, at least, in C57BL/6J and FVB/NJ Dstyk-/- mice. Phenotypic penetrance increased to ∼40% in C3H/HeJ mutants, with mild-to-moderate severity. Re-analysis of the original family segregating the rare SSV showed low penetrance (43.8%) and no alternative genetic causes for CAKUT. LOF DSTYK variants burden showed significant excess for CAKUT and epilepsy vs controls and an exploratory phenome-wide association study supported association with neurological disorders. CONCLUSION: These data support causality for DSTYK LOF variants and highlights the need for large-scale sequencing studies (here >200,000 cases) to accurately assess causality for genes and variants to lowly penetrant traits with common population prevalence.

[Influence of TLR2- and TLR4-activated Mesenchymal Stem Cells on Migration of Cord Blood CD34+ Cells].

OBJECTIVE: This study was aimed to investigate the possible effect of Toll-like receptors 2 (TLR2) and Toll-like receptors 4 (TLR4) on the migration function of umbilical cord blood (UCB) CD34+ hematopoietic stem/progenitor cells induced by bone marrow-derived mesenchymal stem cells (MSCs) and to explore the underlying mechanism. METHODS: The expression of TLR2 and TLR4 on MSC was detected with flow cytometry. After the MSC were pretreated with TLR2 agonist (PAM3CSK4) and/or TLR4 agonist (LPS), the supernatants were collected. The effect of the supernatants on the migration of CD34+ cells was evaluated with chemotaxis assays. Alterations of chemokine (SDF-1) secreted by MSC in the supernatants were assayed by ELISA. RESULTS: The expression levels of TLR2 and TLR4 were (31.5±4.6)% and (85.6±6.7)% respectively. Compared with the blank group, the migration ability of CD34+ cells increased significantly in control, LPS and/or PAM3CSK4 groups (P<0.01). Further study found that LPS and/or PAM3CSK4 enhanced the chemotactic ability of CD34+ cells (P<0.05), but the concentration of SDF-1 was not changed significantly in all of LPS and/or PAM3CSK4 groups (P>0.05) in comparison with the control group. CONCLUSION: TLR2 and TLR4 signalings may indirectly increase the migration of CD34+ hematopoietic stem/progenitor cells by modulating BM-MSC functions, which may not significantly correlate with the production of chemokine SDF-1 by MSCs.