Preclinical evaluation of RQ3013, a broad-spectrum mRNA vaccine against SARS-CoV-2 variants

The global emergence of SARS-CoV-2 variants has led to increasing breakthrough infections in vaccinated populations, calling for an urgent need to develop more effective and broad-spectrum vaccines to combat COVID-19. Here we report the preclinical development of RQ3013, an mRNA vaccine candidate intended to bring broad protection against SARS-CoV-2 variants of concern (VOCs). RQ3013, which contains pseudouridine-modified mRNAs formulated in lipid nanoparticles, encodes the spike(S) protein harboring a combination of mutations responsible for immune evasion of VOCs. Here we characterized the expressed S immunogen and evaluated the immunogenicity, efficacy, and safety of RQ3013 in various animal models. RQ3013 elicited robust immune responses in mice, hamsters, and nonhuman primates (NHP). It can induce high titers of antibodies with broad cross-neutralizing ability against the Wild-type, B.1.1.7, B.1.351, B.1.617.2, and the omicron B.1.1.529 variants. In mice and NHP, two doses of RQ3013 protected the upper and lower respiratory tract against infection by SARS-CoV-2 and its variants. We also proved the safety of RQ3013 in NHP models. Our results provided key support for the evaluation of RQ3013 in clinical trials.

Expression of angiopoietin-1 during scar strophying / 中华医学美学美容杂志

Objective To explore the expression of angiopoietin 1 in scar during the scar strophying.Methods The rabbit ear scar model was established in the same position of each ear ventral center skin regardless of gender.The weight of each rabbit was greater than 2.0 kg weight.The scars were collected at weeks 1,2,4,8,and 12.After 12 weeks of scar tissue samples were collected,together with normal skin tissues in the rabbit ear ventral normal skin.The tissues were preseved in 10％ formalin liquid and cryopreserved in liquid nitrogen,respectively.The general form of scar tissues and the expression of Ang-1 in scar were investigated by hematoxylin and eosin staining and Western-blot.Results The expression of Ang-1 increased gradually,and the highest at 2 week after epithelial change as (0.29±0.11),then decreased gradually,and the lowset at week 12 as (0.00± 0.00),which was close to normal skin expression as (0.05±0.01) (P＜0.05).Conclusions Ang-1 may play an important role during the scar atrophying.

[Therapeutic strategy for different types of epicanthus].

OBJECTIVE: To explore the reasonable therapeutic strategy for different types of epicanthus. METHODS: Patients with epicanthus were classificated according to the shape, extent and inner canthal distance and treated with different methods appropriately. Modified asymmetric Z plasty with two curve method was used in lower eyelid type epicanthus, inner canthus type epicanthus and severe upper eyelid type epicanthus. Moderate upper epicanthus underwent '-' shape method. Mild Upper epicanthus in two conditions which underwent nasal augumentation and double eyelid formation with normal inner canthal distance need no correction surgery. The other mild epicanthus underwent '-' shape method. RESULTS: A total of 66 cases underwent the classification and the appropriate treatment. All wounds healed well. During 3 to 12 months follow-up period, all epicanthus were corrected completely with natural contour and unconspicuous scars. All patients were satisfied with the results. CONCLUSIONS: Classification of epicanthus hosed on the shape, extent and inner canthal distance and correction with appropriate methods is a reasonable therapeutic strategy.