Ferritin nanoparticle based SARS-CoV-2 RBD vaccine induces persistent antibody response and long-term memory in mice

Since the outbreak of COVID-19, over 200 vaccine candidates have been documented and some of them have advanced to clinical trials with encouraging results. However, the antibody persistence over 3 months post immunization and the long-term memory have been rarely reported. Here, we report that a ferritin nanoparticle based SARS-CoV-2 RBD vaccine induced in mice an efficient antibody response which lasts for at least 7 months post immunization. Significantly higher number of memory B cells were maintained and a significantly higher level of recall response was induced upon antigen challenge. Thus, we believe our current study provide the first information about the long-term antibody persistence and memory response of a COVID-19 vaccine. This information would be also timely useful for the development and evaluation of other vaccines.

The Mutations and Sequencing of HPV16E6E7Gene of Human Papillomavirus from Patients with HPV Infection in Beijing / 中华皮肤科杂志

Objective To investigate the gene sequence and mutations of human papillomavirus(HPV)type16E6E7in patients with HPV infection in Beijing.Methods Sample DNA was extracted from lesions in patients with HPV infection.HPV types were identified by polymerase chain reaction(PCR).E6E7gene,isolated from samples infected with HPV16only,was cloned into plasmid pGEM-3zf and sequenced.Results The recombinant plasmid pGEM/16E6E7was constructed successfully.The whole HPV E6E7gene was776bp in length which was equal to that of the standard strain.Three nucleotides exchanges,i.e.,p60PROE6,p96GLUE6,p565SERE7,were found in E6E7gene.Conclusion The data suggest that there are nucleotide differences of HPV E6E7gene between HPV obtained from Beijing and that of standard sequence.