Cheng Wan

Objective: To establish a method to assess risks associated with preimplantation genetic testing (PGT) in embryos simultaneously with adhered sperm and cumulus cells. Design: A prospective pilot study. Setting: University teaching hospital. Patient(s): 120 frozen blastocysts that could be biopsied from 34 patients who had experienced repeated implantation failure or abortion due to chromosomal abnormalities after embryos transfer in prior routine IVF cycles. Intervention(s): Chromosome screening and parental DNA contamination testing was performed in the surplus frozen IVF blastocysts from 34 patients. Main Outcome Measure(s): Parental DNA contamination rate and euploidy rate in biopsied blastocysts. Result(s): A new quantification method for parental contamination testing (qPCT) in single-cell whole-genome amplification (WGA) products based on allelic ratio analysis was established and validated in an artificial model by comparing 22 results obtained before and after adding different numbers of sperm and cumulus cells to biopsied TE cells. The results of the prospective clinical study of qPCT-PGT-A showed that the maternal contamination rate was 0.83% (1/120) and the risk of paternal contamination was negligible. The euploidy rate in these blastocysts was 47.50% (57/120), and 21 frozen embryo transfer (FET) cycles resulted in ten ongoing clinical pregnancies and four healthy births. Conclusion(s): The evidence we provide in the study shows a low risk of PGT in embryos simultaneously with adhered sperm and cumulus cells. The qPCT assay can be used to detect the risk of potential contamination and ensure the accuracy of PGT results, thereby improving the clinical outcome of IVF. Capsule: During PGT for human frozen conventional IVF embryos, paternal source pollution is negligible, while maternal pollution can not be ignored. qPCT method can effectively detect the parent DNA contamination in WGA products of biopsied TE cells.

A microcapillary with a Q factor of 1.3×10 ⁶ and a 2-μm wall thickness is functionalized to detect glucose concentration of 2.78 mM, with sensitivity of 0.974 pm/mM and small sample volume ~ 90 nL.

We demonstrate label-free detection of low glucose concentration based on whispery gallery mode resonance in an optofluidic microcapillary (OFMC) biosensor. The wall surface of the OFMC is bio-chemically functionalized to detect cellular-level glucose concentration as low as 2.78 mM. The measured sensitivity is 0.966 pm/mM. The fabricated microcapillary has a thin wall thickness of 2 μm and a Q factor of 1.3 × 106, corresponding to a bulk refractive index sensitivity of 23.36 nm/RIU. The OFMC biosensor has advantages such as high resistance to environmental perturbation, small sample volume down to 90 nL and cost-effectiveness. Theoretical analysis shows the sensor sensitivity depends on the microcapillary wall thickness and liquid core refractive index.

Hemophagocytic lymphohistiocytosis (HLH) is a rare but fatal disease caused by uncontrolled proliferation of activated lymphocytes and macrophages. Six genes including SH2D1A, PRF1, UNC13D, STX11, STXBP2 and XIAP were reported as causative genes in most cases. Here we report a novel splicing mutation in UNC13D gene, which was identified in an 18-year-old female. Patient was diagnosed as HLH base on HLH-2004 guidelines, no history of inherited diseases was revealed in this family, parents were healthy and non-consanguineous. Splenomegaly and hemophagocytosis in bone marrow were observed in clinical examination. Amplicon sequencing for the whole coding region of 6 HLH-related genes was performed on Ion S5XL genetic analyzer. In all, four heterozygous mutations were detected, including 2 nonpathogenic SNPs (PRF1:c.900C > T, STX11:c.*70G > A) and 2 splicing mutations in UNC13D gene (UNC13D:c.1299 + 1G > A and UNC13D:c.2709 + 1G > A), both of which were predicted to be potentially pathogenic by human splicing finder (HSF3) tool. The result was confirmed by two-generation pedigree analysis base on sanger sequencing. Two compound heterozygous splicing mutations in UNC13D gene were identified and considered to be potential pathogenesis in a female patient of HLH. The mutation UNC13D:c.1299 + 1G > A was reported in HLH for the first time. The inheritance mode and source of the mutation in the proband was examined by family analysis. Our data suggest that further studies of the spectrum of HLH-related mutations in China are warranted.