Engineered AAV13 variants with enhanced transduction and confined spread.

Precise targeting of specific regions within the central nervous system (CNS) is crucial for both scientific research and gene therapy in the context of brain diseases. Adeno-associated virus 13 (AAV13) is known for its restricted diffusion range within the CNS, making it an ideal choice for precise labeling and administration within small brain regions. However, AAV13 mediates relatively low expression of target genes. Here, we introduced specifically engineered modifications to the AAV13 capsid protein to enhance its transduction efficiency. We first constructed AAV13-YF by mutating tyrosine to phenylalanine on the surface of the AAV13 capsid. We then inserted the 7m8 peptide, known to enhance cell transduction, into positions 587/588 and 585/586 of the AAV13 capsid, resulting in two distinct variants named AAV13-587-7m8 and AAV13-585-7m8, respectively. We found that AAV13-YF exhibited superior in vitro infectivity in HEK293T cells compared to AAV13, while AAV13-587-7m8 and AAV13-585-7m8 showed enhanced CNS infection capabilities in C57BL/6 mice, with AAV13-587-7m8 infection retaining a limited spread range. These modified AAV13 variants hold promising potential for applications in gene therapy and neuroscience research.

[Identification, biological characterization, and fungicide screening of pathogen causing southern blight in Aster tataricus].

This study aims to clarify the species and biological characteristics of the pathogen causing southern blight in Aster tataricus and screen out effective fungicides for the prevention and control of this disease. We collected the typical diseased plants and sclerotia on soil surface for the isolation of the pathogen, and identified the pathogen based on morphological characteristics, molecular biological characteristics, and pathogenicity. Further, we evaluated the inhibitory effects of 12 fungicides on the pathogen by plate growth inhibition assay. In the diseased plants, watery brown spots first appeared at the stem base and then spread upward, which were covered with white mycelia and surrounded by white to yellow-brown sclerotia. From the diseased plants, 15 strains with consistent traits were isolated. The pathogen was identified as Athelia rolfsii based on morphological characteristics and ITS and TEF sequences. The pathogenicity test was carried out according to Koch's rule, which showed the disease symptoms consistent with those in the field. The pathogen presented the optimum growth at 28-30 ℃, pH 5-8, and full darkness. The preliminary indoor screening demonstrated that four chemical fungicides(taifujin, hymexazol, flusilazole, and lime-sulphur-synthelic-solution), two botanical fungiticides(ethylicin and garlic oil), and a microbial agent(Bacillus subtilis) had good inhibitory effects on A. rolfsii. The results of gradient inhibition experiments showed that B. subtilis, flusilazole, and ethylicin had stronger inhibitory activity. The further in vivo screening indicated that ethylicin can be used as the main fungicide for the prevention and treatment of southern blight in A. tataricus.

[Acupuncture of intraorbital and extraorbital acupoints reduces apoptosis of retinal ganglion by down-regulating expression of Caspase-3 and ratio of Bax/Bcl-2 in rabbits with nonarteritis anterior ischemic optic neuropathy].

OBJECTIVE: To observe the effect of acupuncture of intraorbital and extraorbital acupoints on apoptosis and expression of Bax, Bcl-2 and Caspase-3 proteins of retinal ganglion tissue in rabbits with nonarteritis anterior ischemic optic neuropathy (NAION), so as to reveal its mechanism underlying improvement of NAION. METHODS: Female New Zealand rabbits were randomly divided into four groups: model, intraocular needling (ION), extraocular needling (EON), ION＋EON groups (n＝5 per group), and the 5 healthy eyes of those rabbits in the model group were selected to be used as the control group. The NAION model of the right eye was established by photodynamic stroke method. For ION group, acupoints "Jingming" (BL1), "Chengqi" (ST1) and "Qiuhou" (EX-HN7) were needled, and for EON group, "Cuanzhu" (BL2), "Yuyao" (EX-HN4) and "Qiaoming" (EX) were needled with filiform needles, followed by retaining the needles for 30 min. For ION＋EON group, the 6 acupoints were needled simutaneously. The treatment was conducted once daily for 3 days. The apoptosis of retinal ganglion tissue was detected by using TUNEL fluorescence labeling, and the expression of Bax, Bcl-2 and active Caspase-3 in the retinal ganglion were detected by immunohistochemistry. RESULTS: Following modeling and compared with the control group, the number of the apoptotic cells, and the expression levels of Bax and Caspase-3 proteins, as well as the ratio of Bax/Bcl-2 were significantly increased in the model group (P<0.01), while the expression of Bcl-2 was significantly decreased (P<0.01). After intervention, the number of the apoptotic cells in the ION, EON and ION＋EON groups, and the ratio of Bax/Bcl-2 in EON and ION＋EON groups, and the expression of Caspase-3 proteins in the ION and ION＋EON groups were significantly down-regulated (P<0.01, P<0.05), and the expression levels of Bcl-2 in both EON and ION＋EON groups were significantly up-regulated in comparison with the model group (P<0.01). No significant changes were found in the expression levels of Bax in the 3 needling groups relevant to the model group (P>0.05). CONCLUSION: Acupuncture of intraorbital and extraorbital acupoints can reduce apoptosis of retinal ganglion in NAION rabbits via inhibiting the activation of Caspase-3 protein and ratio of Bax/Bcl-2, and up-regulating the expression of Bcl-2 protein.