Heterologous vaccination utilizing viral vector and protein platforms confers complete protection against SFTSV.

Severe fever with thrombocytopenia syndrome virus was first discovered in 2009 as the causative agent of severe fever with thrombocytopenia syndrome. Despite its potential threat to public health, no prophylactic vaccine is yet available. This study developed a heterologous prime-boost strategy comprising priming with recombinant replication-deficient human adenovirus type 5 (rAd5) expressing the surface glycoprotein, Gn, and boosting with Gn protein. This vaccination regimen induced balanced Th1/Th2 immune responses and resulted in potent humoral and T cell-mediated responses in mice. It elicited high neutralizing antibody titers in both mice and non-human primates. Transcriptome analysis revealed that rAd5 and Gn proteins induced adaptive and innate immune pathways, respectively. This study provides immunological and mechanistic insight into this heterologous regimen and paves the way for future strategies against emerging infectious diseases.

Analyzing Genetic Differences Between Sporadic Primary and Secondary/Tertiary Hyperparathyroidism by Targeted Next-Generation Panel Sequencing.

Secondary hyperparathyroidism (SHPT) is characterized by excessive serum parathyroid hormone levels in response to decreasing kidney function, and tertiary hyperparathyroidism (THPT) is often the result of a long-standing SHPT. To date, several genes have been associated with the pathogenesis of primary hyperparathyroidism (PHPT). However, the molecular genetic mechanisms of uremic hyperparathyroidism (HPT) remain uncharacterized. To elucidate the differences in genetic alterations between PHPT and SHPT/THPT, the targeted next-generation sequencing of genes associated with HPT was performed using DNA extracted from parathyroid tissues. As a result, 26 variants in 19 PHPT or SHPT/THPT appeared as candidate pathogenic mutations, which corresponded to 9 (35%) nonsense, 8 (31%) frameshift, 6 (23%) missense, and 3 (11%) splice site mutations. The MEN1 (23%, 6/26), ASXL3 (15%, 4/26), EZH2 (12%, 3/26), and MTOR (8%, 2/26) genes were frequently mutated. Sixteen of 25 patients with PHPT (64%) had one or more mutations, whereas 3 (21%) of 21 patients with SHPT/THPT had only 1 mutation (p = 0.001). Sixteen of 28 patients (57%) with parathyroid adenoma (PA) had one or more mutations, whereas 3 of 18 patients (17%) with parathyroid hyperplasia (PH) had just one mutation (p = 0.003). Known driver mutations associated with parathyroid tumorigenesis such as CCND1/PRAD1, CDC73/HRPT2, and MEN1 were identified only in PA (44%, 7/16 with mutations). Our results suggest that molecular genetic abnormalities in SHPT/THPT are distinct from those in PHPT. These findings may help in analyzing the molecular pathogenesis underlying uremic HPT development.

IL-6 and IL-10 Levels, Rather Than Viral Load and Neutralizing Antibody Titers, Determine the Fate of Patients With Severe Fever With Thrombocytopenia Syndrome Virus Infection in South Korea.

Severe fever with thrombocytopenia syndrome (SFTS) is a new tick-borne viral disease, and most SFTS virus (SFTSV) infections occur via bites from the tick Haemaphysalis longicornis; however, SFTSV transmission can also occur through close contact with an infected patient. SFTS is characterized by acute high fever, thrombocytopenia, leukopenia, elevated serum hepatic enzyme levels, gastrointestinal symptoms, and multiorgan failure and has a 16.2 to 30% mortality rate. In this study, we found that age, dyspnea rates, aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase, multiorgan dysfunction score (MODS), viral load, IL-6 levels, and IL-10 levels were higher in patients with fatal disease than in patients with nonfatal disease during the initial clinical course of SFTS. In addition, we found that IL-6 and IL-10 levels, rather than viral load and neutralizing antibody titers, in patients with an SFTSV infection strongly correlated with outcomes (for severe disease with an ultimate outcome of recovery or death).

Peptides Derived From S and N Proteins of Severe Acute Respiratory Syndrome Coronavirus 2 Induce T Cell Responses: A Proof of Concept for T Cell Vaccines.

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants that escape vaccine-induced neutralizing antibodies has indicated the importance of T cell responses against this virus. In this study, we highlight the SARS-CoV-2 epitopes that induce potent T cell responses and discuss whether T cell responses alone are adequate to confer protection against SARS-CoV-2 and describe the administration of 20 peptides with an RNA adjuvant in mice. The peptides have been synthesized based on SARS-CoV-2 spike and nucleocapsid protein sequences. Our study demonstrates that immunization with these peptides significantly increases the proportion of effector memory T cell population and interferon-γ (IFN-γ)-, interleukin-4 (IL-4)-, tumor necrosis factor-α (TNF-α)-, and granzyme B-producing T cells. Of these 20 peptides, four induce the generation of IFN-γ-producing T cells, elicit CD8+ T cell (CTL) responses in a dose-dependent manner, and induce cytotoxic T lymphocytes that eliminate peptide-pulsed target cells in vivo. Although it is not statistically significant, these peptide vaccines reduce viral titers in infected hamsters and alleviate pulmonary pathology in SARS-CoV-2-infected human ACE2 transgenic mice. These findings may aid the design of effective SARS-CoV-2 peptide vaccines, while providing insights into the role of T cells in SARS-CoV-2 infection.

Immunization with RBD-P2 and N protects against SARS-CoV-2 in nonhuman primates.

Since the emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), various vaccines are being developed, with most vaccine candidates focusing on the viral spike protein. Here, we developed a previously unknown subunit vaccine comprising the receptor binding domain (RBD) of the spike protein fused with the tetanus toxoid epitope P2 (RBD-P2) and tested its efficacy in rodents and nonhuman primates (NHPs). We also investigated whether the SARS-CoV-2 nucleocapsid protein (N) could increase vaccine efficacy. Immunization with N and RBD-P2 (RBDP2/N) + alum increased T cell responses in mice and neutralizing antibody levels in rats compared with those obtained using RBD-P2 + alum. Furthermore, in NHPs, RBD-P2/N + alum induced slightly faster SARS-CoV-2 clearance than that induced by RBD-P2 + alum, albeit without statistical significance. Our study supports further development of RBD-P2 as a vaccine candidate against SARS-CoV-2. Also, it provides insights regarding the use of N in protein-based vaccines against SARS-CoV-2.

A novel EPB41 p.Trp704* mutation in a Korean patient with hereditary elliptocytosis: a case report.

Objectives: Hereditary elliptocytosis (HE) is inherited in an autosomal dominant fashion, and the majority of HE-associated defects occur due to qualitative and quantitative defects in the RBC membrane skeleton proteins α-spectrin, ß-spectrin, or protein 4.1R. The complex EPB41 gene encodes a diverse family of protein 4.1R isoforms which are key components of the erythroid membrane skeleton that regulates red cell morphology and mechanical stability. The purpose of this study was to investigate the genome of a Korean patient with HE to discover the causative gene mutation using gene panel sequencing. Methods: An 89-year-old female presented to the Emergency Department and was diagnosed with pancreatitis and gallstones. A peripheral blood smear revealed that approximately 60% of the RBCs were abnormally shaped and appeared oval or elongated, from slightly egg-shaped to rod or pencil forms (elliptocytes). Targeted gene panel sequencing consisting of 33 genes related to inherited RBC disorders and Sanger sequencing were performed. Results: A heterozygous c.2112G > A of the EPB41 gene leading to premature termination codon (NM_001166005.1:c.2112G > A, p.Trp704*) was identified. This variant, which had not been previously reported to be related to HE, was confirmed by Sanger sequencing. Thus, the patient's diagnosis of HE-1 was genetically confirmed. Conclusion: The present study confirmed a novel mutation of the EPB41 gene that plays an important role in expanding the mutational distribution in HE-1. It could also be helpful for understanding the correlation between the genotype and phenotype in HE.

Characteristics of DNMT3A mutations in acute myeloid leukemia.

BACKGROUND: DNMT3A mutations occur in approximately 20% of AML cases and are associated with changes in DNA methylation. CDKN2B plays an important role in the regulation of hematopoietic progenitor cells and DNMT3A mutation is associated with CDKN2B promoter methylation. We analyzed the characteristics of DNMT3A mutations including their clinical significance in AML and their influence on promoter methylation and CDKN2B expression. METHODS: A total of 142 adults, recently diagnosed with de novo AML, were enrolled in the study. Mutations in DNMT3A, CEBPA, and NPM1 were analyzed by bidirectional Sanger sequencing. We evaluated CDKN2B promoter methylation and expression using pyrosequencing and RT-qPCR. RESULTS: We identified DNMT3A mutations in 19.7% (N=28) of enrolled patients with AML, which increased to 29.5% when analysis was restricted to cytogenetically normal-AML. Mutations were located on exons from 8-23, and the majority, including R882, were found to be present on exon 23. We also identified a novel frameshift mutation, c.1590delC, in AML with biallelic mutation of CEBPA. There was no significant difference in CDKN2B promoter methylation according to the presence or type of DNMT3A mutations. CDKN2B expression inversely correlated with CDKN2B promoter methylation and was significantly higher in AML with R882H mutation in DNMT3A. We demonstrated that DNMT3A mutation was associated with poor AML outcomes, especially in cytogenetically normal-AML. The DNMT3A mutation remained as the independent unfavorable prognostic factor after multivariate analysis. CONCLUSION: We characterized DNMT3A mutations in AML and revealed the association between the DNMT3A mutation and CDKN2B expression and clinical outcome.

Inactivated influenza vaccine formulated with single-stranded RNA-based adjuvant confers mucosal immunity and cross-protection against influenza virus infection.

Influenza vaccination is considered the most valuable means to prevent and control seasonal influenza infections, which causes various clinical symptoms, ranging from mild cough and fever to even death. Among various influenza vaccine types, the inactivated subunit type is known to provide improved safety with reduced reactogenicity. However, there are some drawbacks associated with inactivated subunit type vaccines, with the main ones being its low immunogenicity and the induction of Th2-biased immune responses. In this study, we investigated the role of a single-stranded RNA (ssRNA) derived from the intergenic region in the internal ribosome entry site of the Cricket paralysis virus as an adjuvant rather than the universal vaccine for a seasonal inactivated subunit influenza vaccine. The ssRNA adjuvant stimulated not only well-balanced cellular (indicated by IgG2a, IFN-γ, IL-2, and TNF-α) and humoral (indicated by IgG1 and IL-4) immune responses but also a mucosal immune response (indicated by IgA), a key protector against respiratory virus infections. It also increases the HI titer, the surrogate marker of influenza vaccine efficacy. Furthermore, ssRNA adjuvant confers cross-protective immune responses against heterologous influenza virus infection while promoting enhanced viral clearance. Moreover, ssRNA adjuvant increases the number of memory CD4+ and CD8+ T cells, which can be expected to induce long-term immune responses. Therefore, this ssRNA-adjuvanted seasonal inactivated subunit influenza vaccine might be the best influenza vaccine generating robust humoral and cellular immune responses and conferring cross-protective and long-term immunity.

MERS-CoV Spike Protein Vaccine and Inactivated Influenza Vaccine Formulated with Single Strand RNA Adjuvant Induce T-Cell Activation through Intranasal Immunization in Mice.

The effectiveness of vaccines is enhanced by adding adjuvants. Furthermore, the selection of an inoculation route depends on the type of adjuvant used and is important for achieving optimum vaccine efficacy. We investigated the immunological differences between two types of vaccines-spike protein from the Middle East respiratory syndrome virus and inactivated influenza virus vaccine, in combination with a single-stranded RNA adjuvant-administered through various routes (intramuscular, intradermal, and intranasal) to BALB/c mice. Intramuscular immunization with the RNA adjuvant-formulated spike protein elicited the highest humoral immune response, characterized by IgG1 and neutralizing antibody production. Although intranasal immunization did not elicit a humoral response, it showed extensive T-cell activation through large-scale induction of interferon-γ- and interleukin-2-secreting cells, as well as CD4+ T-cell activation in mouse splenocytes. Moreover, only intranasal immunization induced IgA production. When immunized with the inactivated influenza vaccine, administration of the RNA adjuvant via all routes led to protection after viral challenge, regardless of the presence of a vaccine-specific antibody. Therefore, the inoculation route should depend on the type of immune response needed; i.e., the intramuscular route is suitable for eliciting a humoral immune response, whereas the intranasal route is useful for T-cell activation and IgA induction.

Development and validation of multiplex real-time PCR assays for rapid detection of cytomegalovirus, Epstein-Barr virus, and polyomavirus BK in whole blood from transplant candidates.

Transplant recipients are more susceptible to bacterial and viral infections. Cytomegalovirus (CMV), Epstein-Barr virus (EBV), and polyomavirus BK (BK) are risk factors for graft dysfunction. All three of them are latent viruses that can cause serious disease in immunocompromised patients. Mainly qualitative PCR tests are required for diagnosis and quantitative monitoring, which are used to follow the response to transplantation. We developed a multiplex real-time PCR (qPCR) method to detect these viruses during blood screenings of transplant recipients. We also validated analytical and clinical performance tests using the developed multiplex qPCR. The limit of detection (LOD) was 100, 125, and 183 copies/ml for CMV, EBV, and BK, respectively. These results had high linearity (R2 = 0.997) and reproducibility (CV range, 0.95-2.38%, 0.52-3.32%, and 0.31-2.45%, respectively). Among 183 samples, we detected 8 samples that were positive for CMV, while only 6 were positive for EBV, and 3 were positive for BK. Therefore, the viral infection prevalence in transplant candidates was 4.40% for CMV, 3.29% for EBV, and 1.64% for BK. This multiplex qPCR method should be used widely for diagnosing and monitoring latent viral infections in transplant recipients.