No abstract

The X‐linked genetic bleeding disorder caused by deficiency of coagulator factor IX, hemophilia B, is a disease ideally suited for gene therapy with genome editing technology. Here, we identify a family with hemophilia B carrying a novel mutation, Y371D, in the human F9 gene. The CRISPR/Cas9 system was used to generate distinct genetically modified mouse models and confirmed that the novel Y371D mutation resulted in a more severe hemophilia B phenotype than the previously identified Y371S mutation. To develop therapeutic strategies targeting this mutation, we subsequently compared naked DNA constructs versus adenoviral vectors to deliver Cas9 components targeting the F9 Y371D mutation in adult mice. After treatment, hemophilia B mice receiving naked DNA constructs exhibited correction of over 0.56% of F9 alleles in hepatocytes, which was sufficient to restore hemostasis. In contrast, the adenoviral delivery system resulted in a higher corrective efficiency but no therapeutic effects due to severe hepatic toxicity. Our studies suggest that CRISPR/Cas‐mediated in situ genome editing could be a feasible therapeutic strategy for human hereditary diseases, although an efficient and clinically relevant delivery system is required for further clinical studies.

Promising vaccine adjuvants of self‐assembling peptide hydrogels for protein ovalbumin (OVA) are introduced in this study. The hydrogels are formed by the enzyme of phosphatase, and the vaccine adjuvant potency of both l‐ and d‐peptide hydrogels is evaluated. The results indicate that, compared with the clinically used alum adjuvant, both l‐ and d‐peptide hydrogels can increase the IgG production of OVA for about 1.3 and 3.8 times, respectively. Both gels can enhance antigen uptake and induce dendritic cell maturation, and promote and prolong accumulation of antigen in lymph node, as well as evoke germinal center formation. However, the d‐peptide hydrogel with OVA exhibits a slightly more efficient accumulation of OVA in the lymph nodes and seems preventing tumor growth more significantly than its l‐counterpart. With the good biocompatibility and degradability of peptide hydrogels, the hydrogels described in this study have big potential for the production of protein vaccines for immunotherapy against different diseases.

The source of dietary nitrate (NO3) is mainly green, leafy vegetables, partially absorbed into blood through intestinal mucosa. The recycled nitrate is reabsorbed and concentrated by the salivary glands and then secreted into saliva. In 2012, sialin was first discovered as the mammalian membrane nitrate transporter in salivary glands and plays a key role in circulation of inorganic nitrate, providing a scientific basis for further investigation into the circulation and functions of nitrate. Dietary nitrate can be converted to nitrite (NO2) by oral commensal bacteria under the tongue or in the stomach, following which nitrite is converted to nitric oxide (NO) through non-enzymatic synthesis. Previously, nitrate and nitrite were thought to be carcinogenic due to the potential formation of nitrogen compounds, whereas the beneficial functions of NO3--NO2--NO pathway were ignored. Under conditions of hypoxia and ischemia, the production of endogenous NO from L-arginine is inhibited, while the activity of exogenous NO3--NO2--NO is enhanced. Recently, a greater amount of evidence has shown that nitrate and nitrite serve as a reservoir and perform positive biological NO-like functions. Therefore, exogenous dietary nitrate plays an important role in various physiological activities as an effective supplement of nitrite and NO in human body. Here we generally review the source, circulation and bio-functions of dietary nitrate.