Preclinical evaluation of a plant-derived SARS-CoV-2 subunit vaccine: Protective efficacy,immunogenicity, safety,and toxicity

Coronavirus disease 2019 (COVID-19) is an acute respiratory illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The prevention of SARS-CoV-2 transmission has become a global priority. Previously, we showed that a protein subunit vaccine that was developed based on the fusion of the SARS-CoV-2 receptor-binding domain (RBD) to the Fc portion of human IgG1 (RBD-Fc), produced in Nicotiana benthamiana, and adjuvanted with alum, namely, Baiya SARS-CoV-2 Vax 1, induced potent immunological responses in both mice and cynomolgus monkeys. Hence, this study evaluated the protective efficacy, safety, and toxicity of Baiya SARS-CoV-2 Vax 1 in K18-hACE2 mice, monkeys and Wistar rats. Two doses of vaccine were administered three weeks apart on Days 0 and 21. The administration of the vaccine to K18-hACE2 mice reduced viral loads in the lungs and brains of the vaccinated animals and protected the mice against challenge with SARS-CoV-2. In monkeys, the results of safety pharmacology tests, general clinical observations, and a core battery of studies of three vital systems, namely, the central nervous, cardiovascular, and respiratory systems, did not reveal any safety concerns. The toxicology study of the vaccine in rats showed no vaccine-related pathological changes, and all the animals remained healthy under the conditions of this study. Furthermore, the vaccine did not cause any abnormal toxicity in rats and was clinically tolerated even at the highest tested concentration. In addition, general health status, body temperature, local toxicity at the administration site, hematology, and blood chemistry parameters were also monitored. Overall, this work presents the results of the first systematic study of the safety profile of a plant-derived vaccine, Baiya SARS-CoV-2 Vax 1; this approach can be considered a viable strategy for the development of vaccines against COVID-19.     

右美托咪定联合综合体温保护对腔镜手术治疗老年恶性肿瘤患者苏醒期质量及免疫功能的影响

目的 探讨右美托咪定联合综合体温保护对腔镜手术治疗老年恶性肿瘤患者苏醒期质量及免疫功能的影响。方法 选择择期行腔镜手术治疗的老年恶性肿瘤患者90例，随机均分为3组：对照组（C组）、体温保护组（T组）和体温保护联合右美托咪定组（T-D组），每组30例。C组常规体温保护，T组和T-D组综合体温保护；T-D组麻醉诱导前10 min泵注右美托咪定0.5 μg/kg。记录3组患者麻醉诱导开始时（T₀）、手术开始30 min（T₁）、60 min（T₂）、90 min（T₃）、120 min（T₄）以及手术结束时（T₅）的鼻咽温度；于T₀、术后2 h（T₆）、24 h（T₇）和48 h（T₈）时抽取静脉血标本，测定T淋巴细胞亚群（CD3⁺、CD4⁺和CD8⁺）和自然杀伤细胞（NK cell）水平；记录患者术中麻醉药物用量及苏醒期质量指标。结果 与T₀比较，C组T₂～T₅时点鼻咽温度均明显降低（P < 0.05）；与C组比较，T组和T-D组T₂～T₅时点鼻咽温度明显升高（P < 0.05）。与T₀时点比较，C组、T组和T-D组T₆、T₇和T₈时点CD3⁺和NK cell活性均明显降低（P < 0.05）；C组在T₆、T₇和T₈时点，T组和T-D组在T₆和T₇时点，CD4⁺活性均明显降低（P < 0.05）。与C组比较，T组和T-D组T₆和T₇时点CD3⁺细胞活性均明显升高（P < 0.05）；T组在T₇时点，T-D组在T₆和T₇时点，CD4⁺细胞活性均明显升高（P < 0.05）；T组在T₇时点，T-D组在T₆、T₇和T₈时点，NK cell活性均明显升高（P < 0.05）。结论 采用体温保护措施联合右美托咪定能够维持老年恶性肿瘤患者的体温稳定，减少围手术期意外低体温（IPH）的发生，并有效提高患者苏醒期质量，减轻免疫抑制程度，加速患者早期恢复。     

Phase 1/2 clinical trial of COVID-19 vaccine in Japanese participants: A report of interim findings

We initiated a randomized, placebo-controlled, phase 1/2 trial to evaluate the safety and immunogenicity of the S-268019-b recombinant protein vaccine, scheduled as 2 intramuscular injections given 21 days apart, in 60 randomized healthy Japanese adults. We evaluated 2 regimens of the S-910823 antigen (5 μg [n = 24] and 10 μg [n = 24]) with an oil-in-water emulsion formulation and compared against placebo (n = 12). Reactogenicity was mild in most participants. No serious adverse events were noted. For both regimens, vaccination resulted in robust IgG and neutralizing antibody production at days 36 and 50 and predominant T-helper 1-mediated immune reaction, as evident through antigen-specific polyfunctional CD4+ T-cell responses with IFN-γ, IL-2, and IL-4 production on spike protein peptides stimulation. Based on the interim analysis, the S-268019-b vaccine is safe, produces neutralizing antibodies titer comparable with that in convalescent serum from COVID-19-recovered patients. However, further evaluation of the vaccine in a large clinical trial is warranted.     

PARP7 negatively regulates the type I interferon response in cancer cells and its inhibition triggers antitumor immunity

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动脉三级淋巴组织与动脉粥样硬化关系的研究进展

学者们对动脉血管的研究常聚焦在血管内膜动脉粥样硬化(As)斑块的形成,而很少关注血管外膜的免疫反应及其对疾病病程的影响。前期研究发现,老龄的ApoE－/－小鼠动脉外膜出现免疫细胞的有序集聚,形成类似淋巴结的异位淋巴组织,称之为动脉三级淋巴组织(ATLO),其形成对内膜As具有明显的调控作用。ATLO的发现及研究为As的研究指明了新的方向,并为其他疾病状况下三级淋巴组织(TLO)的研究提供了很好的范例。因此,阐明TLO的特点及形成机制对As的防治具有重要的意义,并为其在其他疾病中的临床运用提供坚实的基础。     

Dendritic cells can prime anti-tumor CD8+ T cell responses through major histocompatibility complex cross-dressing

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