Vaccination is the most effective measure for reducing and preventing influenza and related complications. In this study, we analyzed the mutation trend and the antigen dominant site changes of the amino acid sequence of hemagglutinin subunit 1 (HA1) of human influenza A virus (IAV) in the northern hemisphere from 2012 to 2022. According to the HA1 sequences of A/Darwin/6/2021 (H3N2) and A/Wisconsin/588/2019 (H1N1) recommended by the World Health Organization in the 2022 influenza season in northern hemisphere, we employed the mosaic algorithm to design three Mosaic-HA1 antigens through stepwise substitution. Mosaic-HA1 was expressed and purified in 293F cells and then mixed with the alum adjuvant at a volume ratio of 1:1. The mixture was used to immunize BALB/c mice, and the immunogenicity was evaluated. Enzyme-linked immunosorbent assay showed that Mosaic-HA1 induced the production of IgG targeting two types of HA1, the specific IgG titers for binding to H3 protein and H1 protein reached 10⁵ and 10³ respectively. The challenge test showed that Mosaic-HA1 protected mice from H3N2 or H1N1. This study designs the vaccines by recombination of major antigenic sites in different subtypes of IAV, giving new insights into the development of multivalent subunit vaccines against influenza.
Animals ; Influenza A Virus, H1N1 Subtype/genetics* ; Influenza A Virus, H3N2 Subtype/genetics* ; Mice, Inbred BALB C ; Mice ; Influenza Vaccines/genetics* ; Hemagglutinin Glycoproteins, Influenza Virus/genetics* ; Humans ; Antibodies, Viral/blood* ; Antigens, Viral/genetics* ; Immunoglobulin G/immunology* ; Female ; Orthomyxoviridae Infections/prevention & control* ; HEK293 Cells

PURPOSE: This study was performed to investigate the epidemiologic and clinical features of human metapneumovirus (hMPV). METHODS: We performed real-time reverse transcription polymerase chain reaction with nasopharyngeal samples from 2,403 children who were hospitalized with acute respiratory infection. Then medical records of 120 children, who were diagnosed with hMPV respiratory infection between 2011 and 2014, were retrospectively analyzed retrospectively and compared to epidemiologic data on respiratory virus infection reported by Korea Centers for Disease Control and Prevention. RESULTS: We detected 120 hMPV-positive cases out of 1,723 virus-positive specimens (7.0%), which prevailed mostly in spring between March and May. Respiratory infection with hMPV was more common in female patients (55.0%) and hPMV infection was prevalent among children aged <5 years (80.8%). Coinfections with other respiratory viruses were observed in 34 patients of 120 hMPV-positive cases (28.3%), mostly with rhinovirus (52.9%). In addition, hPMV infection mostly presented with pneumonia (71.7%). Among 120 hMPV-positive patients during the recent 4 years, most (68.3%) were diagnosed in 2014. During 2011–2014, influenza virus infection was prevalent mainly from January to March, and hMPV infection started to appear just after the end of influenza virus outbreak. CONCLUSION: In Korean children, hMPV was a common causative organism of viral pneumonia during the spring season. The hMPV infection pandemic was observed in 2014 and the clinical importance of hMPV has recently been increasing. Therefore, additional studies are required to define the epidemiology, disease characteristics caused by hMPV, and the cause of recent outbreak.
Centers for Disease Control and Prevention (U.S.) ; Child* ; Coinfection ; Epidemiology* ; Female ; Humans* ; Korea ; Medical Records ; Metapneumovirus* ; Orthomyxoviridae ; Pandemics ; Pneumonia ; Pneumonia, Viral ; Polymerase Chain Reaction ; Respiratory Tract Infections ; Retrospective Studies ; Reverse Transcription ; Rhinovirus ; Seasons

Swine influenza viruses (SwIVs) cause considerable morbidity and mortality in domestic pigs, resulting in a significant economic burden. Moreover, pigs have been considered to be a possible mixing vessel in which novel strains loom. Here, we developed and evaluated a novel M2e-multiple antigenic peptide (M2e-MAP) as a supplemental antigen for inactivated H3N2 vaccine to provide cross-protection against two main subtypes of SwIVs, H1N1 and H3N2. The novel tetra-branched MAP was constructed by fusing four copies of M2e to one copy of foreign T helper cell epitopes. A high-yield reassortant H3N2 virus was generated by plasmid based reverse genetics. The efficacy of the novel H3N2 inactivated vaccines with or without M2e-MAP supplementation was evaluated in a mouse model. M2e-MAP conjugated vaccine induced strong antibody responses in mice. Complete protection against the heterologous swine H1N1 virus was observed in mice vaccinated with M2e-MAP combined vaccine. Moreover, this novel peptide confers protection against lethal challenge of A/Puerto Rico/8/34 (H1N1). Taken together, our results suggest the combined immunization of reassortant inactivated H3N2 vaccine and the novel M2e-MAP provided cross-protection against swine and human viruses and may serve as a promising approach for influenza vaccine development.
Animals ; Antibodies, Viral/blood ; Antigens, Viral/genetics/*immunology ; Body Weight ; Cross Protection/*immunology ; Disease Models, Animal ; Epitopes, T-Lymphocyte/genetics/immunology ; Female ; Influenza A Virus, H3N2 Subtype/genetics/*immunology ; Influenza Vaccines/*immunology ; Mice ; Mice, Inbred BALB C ; Orthomyxoviridae Infections/*immunology/mortality/pathology/prevention & control ; Peptides/genetics/*immunology ; Random Allocation ; Survival Analysis ; Vaccines, Synthetic/immunology ; Virus Replication

OBJECTIVETo investigate the preventive effects of Qiangzhi Decoction (, QZD) on influenza A pneumonia through inhibition of inflammatory cytokine storm in vivo and in vitro.

METHODSOne hundred ICR mice were randomly divided into the virus control, the Tamiflu control and the QZD high-, medium-, and low-dose groups. Mice were infected intranasally with influenza virus (H1N1) at 10 median lethal dose (LD50). QZD and Tamiflu were administered intragastrically twice daily from day 0 to day 7 after infection. The virus control group was treated with distilled water alone under the same condition. The number of surviving mice was recorded daily for 14 days after viral infection. The histological damage and viral replication and the expression of inflammatory cytokines were monitored. Additionally, the suppression capacity on the secretion of regulated on activation normal T cells expressed and secreted (RANTES) and tumor necrosis factor-α (TNF-α) in epithelial and macrophage cell-lines were evaluated.

RESULTSCompared with the virus control group, the survival rate of the QZD groups significantly improved in a dose-dependent manner (P<0.05), the viral titers in lung tissue was inhibited (P<0.05), and the production of inflammatory cytokines interferon-γ (IFN-γ), interleukin-6 (IL-6), TNF-α, and intercellular adhesion molecule-1 (ICAM-1) were suppressed (P<0.05). Meanwhile, the secretion of RANTETS and TNF-α by epithelial and macrophage cell-lines was inhibited with the treatment of QZD respectively in vitro (p<0.05) CONCLUSIONS: The preventive effects of QZD on influenza virus infection might be due to its unique cytokine inhibition mechanism. QZD may have significant therapeutic potential in combination with antiviral drugs.

Animals ; Cell Line ; Cell Survival ; drug effects ; Chemokine CCL5 ; metabolism ; Chemokines ; metabolism ; Cytokines ; metabolism ; Dogs ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Enzyme-Linked Immunosorbent Assay ; Hemagglutination, Viral ; drug effects ; Humans ; Inflammation ; pathology ; Influenza A Virus, H1N1 Subtype ; drug effects ; physiology ; Influenza A Virus, H1N2 Subtype ; drug effects ; Lung ; drug effects ; pathology ; Madin Darby Canine Kidney Cells ; Mice, Inbred ICR ; Orthomyxoviridae Infections ; complications ; pathology ; prevention & control ; Pneumonia ; complications ; pathology ; prevention & control ; Protective Agents ; pharmacology ; therapeutic use ; Survival Rate ; Tumor Necrosis Factor-alpha ; pharmacology

BACKGROUND AND OBJECTIVES: This study is aimed at elucidating potential temporal associations between the occurrence of Kawasaki disease (KD) and various viral infections. SUBJECTS AND METHODS: We obtained monthly patterns of KD from the seventh nationwide survey and viral detection data from the Korea Centers for Disease Control and Prevention from 2009 to 2011 and evaluated temporal correlations between them for each month. The respiratory viruses detected using a multiplex real-time-polymerase chain reaction kit were influenza virus (A/H1N1, A/H3N2, A/H5N1, and B), adenovirus, parainfluenza virus (type 1, 2, 3), respiratory syncytial virus (type A, B), human rhinovirus, human coronavirus (OC43/229E, NL63), human bocavirus, and enterovirus. RESULTS: We obtained data from a total of 13031 patients who were treated for acute KD from 87 hospitals with pediatric residence programs. During this survey, KD showed highest overall incidence in summer and winter seasons and lowest incidence in February and October. We received viral detection data for a total of 14267 patients. Viral detection was highest during winter and spring seasons. The most commonly detected virus was human rhinovirus (32.6%), followed by influenza virus (26.8%). The monthly incidence of KD showed significant correlation with the monthly overall viral detection (p=0.022, r=0.382). In particular, human bocavirus and enterovirus have significant correlations with monthly patterns of KD occurrence (p=0.032 and p=0.007, respectively) and influenza virus correlated with KD occurrence with borderline significance (p=0.063). CONCLUSION: The temporal association between monthly occurrence of KD and viral detection suggests the etiologic importance of precedent infection in the development of KD.
Adenoviridae ; Centers for Disease Control and Prevention (U.S.) ; Coronavirus ; Enterovirus ; Human bocavirus ; Humans ; Incidence ; Korea ; Mucocutaneous Lymph Node Syndrome* ; Orthomyxoviridae ; Paramyxoviridae Infections ; Respiratory Syncytial Viruses ; Rhinovirus ; Seasons

Novel reassortant H3N2 swine influenza viruses (SwIV) with the matrix gene from the 2009 H1N1 pandemic virus have been isolated in many countries as well as during outbreaks in multiple states in the United States, indicating that H3N2 SwIV might be a potential threat to public health. Since southern China is the world's largest producer of pigs, efficient vaccines should be developed to prevent pigs from acquiring H3N2 subtype SwIV infections, and thus limit the possibility of SwIV infection at agricultural fairs. In this study, a high-growth reassortant virus (GD/PR8) was generated by plasmid-based reverse genetics and tested as a candidate inactivated vaccine. The protective efficacy of this vaccine was evaluated in mice by challenging them with another H3N2 SwIV isolate [A/Swine/Heilongjiang/1/05 (H3N2) (HLJ/05)]. Prime and booster inoculation with GD/PR8 vaccine yielded high-titer serum hemagglutination inhibiting antibodies and IgG antibodies. Complete protection of mice against H3N2 SwIV was observed, with significantly reduced lung lesion and viral loads in vaccine-inoculated mice relative to mock-vaccinated controls. These results suggest that the GD/PR8 vaccine may serve as a promising candidate for rapid intervention of H3N2 SwIV outbreaks in China.
Animals ; Female ; Influenza A Virus, H3N2 Subtype/*genetics/immunology ; Influenza Vaccines/genetics/immunology/*therapeutic use ; Mice ; Mice, Inbred BALB C ; Orthomyxoviridae Infections/immunology/*prevention & control/virology ; Reassortant Viruses/genetics/immunology ; Reverse Genetics/methods/*veterinary ; Swine ; Swine Diseases/immunology/*prevention & control/virology ; Vaccines, Inactivated ; Virus Replication

Animals ; Communicable Disease Control ; Epidemiological Monitoring ; Humans ; Influenza, Human ; prevention & control ; Orthomyxoviridae Infections ; prevention & control

To investigate the seasonal influenza split vaccine's immune protective effectiveness against the homologous and heterogonous subtypes of influenza A virus challenge and the relationship between the protective effectiveness and hemagglutination inhibition (HI) antibody titer in mice. Two components of H1N1 and H3N2 in Chinese 2008-2009 seasonal influenza spilt vaccine, were derived from vaccine strain A/Brisbane/59/2007 (H1N1)-like virus and A/Brisbane/10/2007 (H3N2)-like virus respectively, and were used to immune BALB/c mice. Firstly, different doses of the vaccines were used to immunize mice and the HA immunization dosage that can induce the HI antibody titer of 40 in mice was identified; Secondly, H1N1 vaccine immunized mice were challenged with different doses of influenza virus mouse adaptation strains of A/Brisbane/59/2007 (H1N1)-like virus (MA) (referred to as A1 virus, well matched-strain in the homologous subtype) and A/Purto Rico/8/34 (H1N1) (referred to as PR8 virus, poor matched-strain in the homologous subtype) respectively, and H3N2 vaccine immunized mice were challenged with H1N1 influenza virus of A1 strain (Heterogonous subtype), body weight changes and survival rates were observed to explore the immune protective effectiveness of influenza split vaccine against the homologous and heterogonous subtypes of influenza A virus in mice. Results indicated that HI antibody titers were elevated as the HA protein immunization dosages increased from 0.15 microg, 0.5 microg, 1.5 microg, 5 microg to 15 microg in mice, and 1.5 microg HA of the seasonal influenza split vaccine could induced HI antibody titer of 40 in mice; 3LD50, 10LD50, 30LD50, 100LD50, 300LD50,1000LD50 and 3000LD50 of influenza virus strain A1 were used to challenge the H1N1 immunization mice, 1.5 microg HA of H1N1 vaccine could 100% protect mice against challenge with 1000LD50 of matched and homologous subtype of influenza virus strains A1, mice immunized with 15 microg HA of H1N1 vaccine even could 100% protect mice against challenge with 3000LD50 of influenza virus strains A1; but mice immunized with both the 1.5 microg and 15 microg HA of H1N1 vaccine were all sacrificed when challenged with 3LD50 of the mismatched and homologous subtype of influenza virus strain PR8, and mice immunized with the high dosage of 15 microg HA of H3N2 vaccine also were all sacrificed when challenged with 3LD50 of the heterogonous subtype of influenza virus strain A1. These results suggest that 1.5 microg HA of seasonal influenza split vaccine could induced HI antibody titer of 40 after one dose in mice, this dosage of HA can effectively protect mice against matched homologous subtype of influenza virus strain, but hardly to protect mice against mismatched homologous or heterogonous subtype of influenza virus strain. These results provide materials for the establishment of influenza vaccine evaluation system based on seasonal influenza vaccine.
Animals ; Antibodies, Viral ; blood ; Cells, Cultured ; Chick Embryo ; Dogs ; Female ; Influenza A Virus, H1N1 Subtype ; immunology ; Influenza Vaccines ; immunology ; Mice ; Mice, Inbred BALB C ; Orthomyxoviridae Infections ; prevention & control ; Vaccination

It is to investigate the effect of two kinds of Houttuynia Cordata Injection on preventing and treating H1N1 influenza virus infection in mice. Pneumonia model was set up by intranasal infection of the normal and immunocompromised mice with influenza virus FM1 and PR8. The two injections were administered before and after the administration of virus, separately, and the lung index was observed. The results showed that the two preparations have obvious therapeutic effect on normal mice infected with influenza virus FM1 and PR8. And to FM1, the new injection's effect is better at small dosage. The results also showed that the two preparations have obvious prophylactic effect on immunodepressed mice infected with influenza virus FM1 and PR8. And to PR8, the old injection's effect is better at small dosage. Houttuynia Cordata Injection can improve the mice pneumonia caused by influenza virus H1N1 and decrease the lung index markedly. It has a remarkable preventive and therapeutic effect on H1N1 influenza virus in mice.
Animals ; Antiviral Agents ; administration & dosage ; therapeutic use ; Drugs, Chinese Herbal ; administration & dosage ; isolation & purification ; therapeutic use ; Female ; Houttuynia ; chemistry ; Immunocompromised Host ; Influenza A Virus, H1N1 Subtype ; drug effects ; immunology ; Injections ; Male ; Mice ; Mice, Inbred ICR ; Orthomyxoviridae Infections ; complications ; drug therapy ; immunology ; prevention & control ; Plants, Medicinal ; chemistry ; Pneumonia, Viral ; drug therapy ; etiology ; prevention & control ; Random Allocation

OBJECTIVETo elevate the immunological effect of subunit influenza vaccine in infants and aged people (over 60) using liposomal adjuvant in the context of its relatively low immunity and to investigate the relation between vaccine antigens and liposomal characteristics.

METHODSSeveral formulations of liposomal subunit influenza vaccine were prepared. Their relevant characteristics were investigated to optimize the preparation method. Antisera obtained from immunizinged mice were used to evaluate the antibody titers of various samples by HI and ELISA.

RESULTSLiposomal trivalent influenza vaccine prepared by film evaporation in combinedation with freeze-drying significantly increased its immunological effect in SPF Balb/c mice. Liposomal vaccine stimulated the antibody titer of H3N2, H1N1, and B much stronger than conventional influenza vaccine. As a result, liposomal vaccine (mean size: 4.5-5.5 microm, entrapment efficiency: 30%-40%) significantly increased the immunological effect of subunit influenza vaccine.

CONCLUSIONThe immune effect of liposomal vaccine depends on different antigens, and enhanced immunity is not positively correlated with the mean size of liposome or its entrapped efficiency.

Animals ; Influenza A Virus, H1N1 Subtype ; immunology ; Influenza A Virus, H3N2 Subtype ; immunology ; Influenza B virus ; immunology ; Influenza Vaccines ; administration & dosage ; immunology ; Liposomes ; Mice ; Mice, Inbred BALB C ; Orthomyxoviridae Infections ; prevention & control ; Specific Pathogen-Free Organisms ; Vaccines, Subunit ; administration & dosage ; immunology