SARS-CoV-2 spike-ferritin-nanoparticle adjuvanted with ALFQ induces long-lived plasma cells and cross-neutralizing antibodies.

This study demonstrates the impact of adjuvant on the development of T follicular helper (Tfh) and B cells, and their influence on antibody responses in mice vaccinated with SARS-CoV-2-spike-ferritin-nanoparticle (SpFN) adjuvanted with either Army Liposome Formulation containing QS-21 (SpFN + ALFQ) or Alhydrogel® (SpFN + AH). SpFN + ALFQ increased the size and frequency of germinal center (GC) B cells in the vaccine-draining lymph nodes and increased the frequency of antigen-specific naive B cells. A single vaccination with SpFN + ALFQ resulted in a higher frequency of IL-21-producing-spike-specific Tfh and GC B cells in the draining lymph nodes and spleen, S-2P protein-specific IgM and IgG antibodies, and elicitation of robust cross-neutralizing antibodies against SARS-CoV-2 variants as early as day 7, which was enhanced by a second vaccination. This was associated with the generation of high titer, high avidity binding antibodies. The third vaccination with SpFN + ALFQ elicited high levels of neutralizing antibodies against the Omicron variant. No cross-neutralizing antibodies against Omicron were induced with SpFN + AH. These findings highlight the importance of ALFQ in orchestrating early induction of antigen-specific Tfh and GC B cell responses and long-lived plasma cells in the bone marrow. The early engagement of S-2P specific naive B cells and high titer IgM antibodies shape the development of long-term neutralization breadth.

Stress Experience of COVID-19 Patients as Reported by Psychological Supporters in South Korea: A Qualitative Study.

Background: COVID-19 patients experience various stressors during the quarantine period and after release from quarantine. However, stressors experienced during each period remain unclear. Methods: A total of 15 mental health experts from the integrated psychological support group for COVID-19participated in this study. Psychological support was provided for the total 932 confirmed COVID-19 patients and their families. Qualitative data were collected using Focus Group Interview (FGI). The participants were divided into two groups and semi-structured questions were used to allow participants to speak their minds. Results: During the quarantine period, difficulties of being diagnosed with COVID-19, concerns about recovery from COVID-19, stress related to quarantine, issues related to the treatment environment, and limited information about COVID-19 and communication were frequently reported. After release from quarantine, the reported main stressors include reinfection or reactivation, concerns about complications, and financial difficulties. Confusion as vectors and victims, stigma and discrimination, and conflicts within a family were observed during both periods. Conclusions: COVID-19 patients suffered various stressors during the quarantine period and after release from quarantine. Moreover, returning to their daily life required timely psychosocial support, intervention, and treatment for COVID-19 infection.

Stress Experience of COVID-19 Patients as Reported by Psychological Supporters in South Korea: A Qualitative Study

Background: COVID-19 patients experience various stressors during the quarantine period and after release from quarantine. However, stressors experienced during each period remain unclear. Methods A total of 15 mental health experts from the integrated psychological support group for COVID-19participated in this study. Psychological support was provided for the total 932 confirmed COVID-19 patients and their families. Qualitative data were collected using Focus Group Interview (FGI). The participants were divided into two groups and semi-structured questions were used to allow participants to speak their minds. Results During the quarantine period, difficulties of being diagnosed with COVID-19, concerns about recovery from COVID-19, stress related to quarantine, issues related to the treatment environment, and limited information about COVID-19 and communication were frequently reported. After release from quarantine, the reported main stressors include reinfection or reactivation, concerns about complications, and financial difficulties. Confusion as vectors and victims, stigma and discrimination, and conflicts within a family were observed during both periods. Conclusions COVID-19 patients suffered various stressors during the quarantine period and after release from quarantine. Moreover, returning to their daily life required timely psychosocial support, intervention, and treatment for COVID-19 infection.

SF-qPCR: Strand Displacement-Based Fast Quantitative Polymerase Chain Reaction.

Nucleic acid testing (NAT) is important for the identification and quantification of specific nucleic acid targets, both DNA and RNA, in life sciences and clinical diagnostics. Nucleic acid amplification can be a time-consuming step in NAT using the polymerase chain reaction (PCR) assay. Therefore, this study aimed to develop a simple method to reduce the amplification time while maintaining the PCR system. The three-step process of a general qPCR was reduced to a two-step process. The annealing/extension temperatures were increased to minimize the differences between the denaturation temperature and the annealing/extension temperatures. Subsequently, the time for each of these steps was reduced and, finally, the denaturation temperature was lowered. Taq polymerase was replaced with SD polymerase because it has strand displacement activity and is efficient in amplifying partial dsDNA at lower denaturation temperatures. In the two-step qPCR of genomic DNA using SD polymerase, the final conditions included an initial denaturation at 92 °C for 2 min, and 1 s at each cycling step with a denaturation temperature of 87 °C and an annealing/extension temperature of 72 °C. Amplification of the nucleocapsid (N) gene of SARS-CoV-2 RNA virus was evaluated at a template concentration as low as 10 copies. This method, named SF-qPCR (strand displacement-based fast quantitative polymerase chain reaction), can stably detect less than 10 copies of DNA and RNA within 25-40 min. This new protocol allows for sensitive and rapid detection of important DNA and RNA targets in clinical diagnosis. Supplementary Information: The online version contains supplementary material available at 10.1007/s13206-021-00044-x.

SF-qPCR: Strand Displacement-Based Fast Quantitative Polymerase Chain Reaction

Nucleic acid testing (NAT) is important for the identification and quantification of specific nucleic acid targets, both DNA and RNA, in life sciences and clinical diagnostics. Nucleic acid amplification can be a time-consuming step in NAT using the polymerase chain reaction (PCR) assay. Therefore, this study aimed to develop a simple method to reduce the amplification time while maintaining the PCR system. The three-step process of a general qPCR was reduced to a two-step process. The annealing/extension temperatures were increased to minimize the differences between the denaturation temperature and the annealing/extension temperatures. Subsequently, the time for each of these steps was reduced and, finally, the denaturation temperature was lowered. Taq polymerase was replaced with SD polymerase because it has strand displacement activity and is efficient in amplifying partial dsDNA at lower denaturation temperatures. In the two-step qPCR of genomic DNA using SD polymerase, the final conditions included an initial denaturation at 92 °C for 2 min, and 1 s at each cycling step with a denaturation temperature of 87 °C and an annealing/extension temperature of 72 °C. Amplification of the nucleocapsid (N) gene of SARS-CoV-2 RNA virus was evaluated at a template concentration as low as 10 copies. This method, named SF-qPCR (strand displacement-based fast quantitative polymerase chain reaction), can stably detect less than 10 copies of DNA and RNA within 25–40 min. This new protocol allows for sensitive and rapid detection of important DNA and RNA targets in clinical diagnosis. Supplementary Information The online version contains supplementary material available at 10.1007/s13206-021-00044-x.

SARS-CoV-2 ferritin nanoparticle vaccines elicit broad SARS coronavirus immunogenicity.

The need for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) next-generation vaccines has been highlighted by the rise of variants of concern (VoCs) and the long-term threat of emerging coronaviruses. Here, we design and characterize four categories of engineered nanoparticle immunogens that recapitulate the structural and antigenic properties of the prefusion SARS-CoV-2 spike (S), S1, and receptor-binding domain (RBD). These immunogens induce robust S binding, ACE2 inhibition, and authentic and pseudovirus neutralizing antibodies against SARS-CoV-2. A spike-ferritin nanoparticle (SpFN) vaccine elicits neutralizing titers (ID50 > 10,000) following a single immunization, whereas RBD-ferritin nanoparticle (RFN) immunogens elicit similar responses after two immunizations and also show durable and potent neutralization against circulating VoCs. Passive transfer of immunoglobulin G (IgG) purified from SpFN- or RFN-immunized mice protects K18-hACE2 transgenic mice from a lethal SARS-CoV-2 challenge. Furthermore, S-domain nanoparticle immunization elicits ACE2-blocking activity and ID50 neutralizing antibody titers >2,000 against SARS-CoV-1, highlighting the broad response elicited by these immunogens.

Current approaches to HIV vaccine development: a narrative review.

INTRODUCTION: The development of an effective vaccine to protect against HIV is a longstanding global health need complicated by challenges inherent to HIV biology and to the execution of vaccine efficacy testing in the context of evolving biomedical prevention interventions. This review describes lessons learnt from previous efficacy trials, highlights unanswered questions, and surveys new approaches in vaccine development addressing these gaps. METHODS: We conducted a targeted peer-reviewed literature search of articles and conference abstracts from 1989 through 2021 for HIV vaccine studies and clinical trials. The US National Library of Medicine's Clinical Trials database was accessed to further identify clinical trials involving HIV vaccines. The content of the review was also informed by the authors' own experience and engagement with collaborators in HIV vaccine research. DISCUSSION: The HIV vaccine field has successfully developed multiple vaccine platforms through advanced clinical studies; however, the modest efficacy signal of the RV144 Thai trial remains the only demonstration of HIV vaccine protection in humans. Current vaccine strategies include prime-boost strategies to improve elicitation of immune correlates derived from RV144, combination mosaic antigens, novel viral vectors, antigens designed to elicit broadly neutralizing antibody, new nucleic acid platforms and potent adjuvants to enhance immunogenicity across multiple classes of emerging vaccine candidates. CONCLUSIONS: HIV vaccine developers have applied lessons learnt from previous successes and failures to innovative vaccine design approaches. These strategies have yielded novel mosaic antigen constructs now in efficacy testing, produced a diverse pipeline of early-stage immunogens and novel adjuvants, and advanced the field towards a globally effective HIV vaccine.