Abstract: An object of the present invention is to provide a novel agent for inhibiting proliferation of SARS-COV-2 and a novel agent for preventing onset of COVID-19. According to the present invention, there is provided an agent for inhibiting proliferation of SARS-CoV-2 comprising a lactic acid bacterium as an active ingredient. Also, according to the present invention, there is provided an agent for preventing onset of COVID-19 comprising a lactic acid bacterium as an active ingredient. The lactic acid bacterium which is the active ingredient of the present invention is preferably Lactococcus lactis subsp. lactis. The agent of the present invention is preferably in the form of a food composition.

Abstract: In this invention, a non-infectious particle has been produced, comprising a pathogen antigen protein caused to be expressed on the surface of a virus particle having at least one species of paramyxovirus envelope protein missing from the particle. This particle has been found to hold within the particle a large amount of antigen protein compared to an infectious particle, and to be capable of eliciting a host immune response with extremely high efficiency. The non-infectious particle according to the present invention is useful as a vaccine against a pathogenic virus, or the like.

Abstract: The present invention provides polypeptides for selectively inducing target antigen-specific CD8-positive T-cell responses. Since induction of human immunodeficiency virus (HIV)-specific CD4-positive T-cell responses by vaccine could promote HIV infection, an HIV vaccine antigen that selectively induces HIV-specific CD8-positive T-cell responses would be useful if obtained. Thus, in the present invention, polypeptide antigens were designed in which 8- to 12-residue amino acid sequences divided from the amino acid sequence of a target antigen protein were connected in an order different from that of the original amino acid sequence. DNA and viral vector vaccines expressing these antigens were tested by inoculation into monkeys. As a result, they were shown to be able to efficiently induce antigen-specific CD8-positive T-cell responses in a selective manner. The instant antigens may be useful as vaccine antigens that induce CD8-positive T cells in a highly selective manner.

Abstract: In this invention, a non-infectious particle has been produced, comprising a pathogen antigen protein caused to be expressed on the surface of a virus particle having at least one species of paramyxovirus envelope protein missing from the particle. This particle has been found to hold within the particle a large amount of antigen protein compared to an infectious particle, and to be capable of eliciting a host immune response with extremely high efficiency. The non-infectious particle according to the present invention is useful as a vaccine against a pathogenic virus, or the like.

Abstract: The present invention provides a vaccine containing a Sendai virus vector encoding a virus protein of an immunodeficiency virus. By intranasally administering a Sendai virus encoding a virus protein of an immunodeficiency virus to a macaque monkey, the present inventors have succeeded in efficiently inducing protective immunity against an immunodeficiency virus. As a result of intranasal inoculation of vaccine, expression of an antigen protein mediated by Sendai virus vector was detected in intranasal mucous membrane and local lymph nodes and antigen-specific cellular immune response was induced at a significant level. No pathological symptom by vaccination was observed. After vaccination, exposure of simian immunodeficiency virus was performed and the effect was examined. As a result, the amount of virus in plasma significantly decreased, compared with that of the control animal. The present invention provides a promising vaccine as an AIDS vaccine.

Abstract: The present invention provides a vaccine containing a Sendai virus vector encoding a virus protein of an immunodeficiency virus. By intranasally administering a Sendai virus encoding a virus protein of an immunodeficiency virus to a macaque monkey, the present inventors have succeeded in efficiently inducing protective immunity against an immunodeficiency virus. As a result of intranasal inoculation of vaccine, expression of an antigen protein mediated by Sendai virus vector was detected in intranasal mucous membrane and local lymph nodes and antigen-specific cellular immune response was induced at a significant level. No pathological symptom by vaccination was observed. After vaccination, exposure of simian immunodeficiency virus was performed and the effect was examined. As a result, the amount of virus in plasma significantly decreased, compared with that of the control animal. The present invention provides a promising vaccine as an AIDS vaccine.

Abstract: The present invention provides a vaccine containing a Sendai virus vector encoding a virus protein of an immunodeficiency virus. By intranasally administering a Sendai virus encoding a virus protein of an immunodeficiency virus to a macaque monkey, the present inventors have succeeded in efficiently inducing protective immunity against an immunodeficiency virus. As a result of intranasal inoculation of vaccine, expression of an antigen protein mediated by Sendai virus vector was detected in intranasal mucous membrane and local lymph nodes and antigen-specific cellular immune response was induced at a significant level. No pathological symptom by vaccination was observed. After vaccination, exposure of simian immunodeficiency virus was performed and the effect was examined. As a result, the amount of virus in plasma significantly decreased, compared with that of the control animal. The present invention provides a promising vaccine as an AIDS vaccine.