The present invention relates to a synthetic saccharide of general formulate (I) that is related to Clostridium difficile PS-II cell-surface polysaccharide and conjugate thereof. Said synthetic saccharide, said conjugate and pharmaceutical composition containing said synthetic saccharide or said conjugate are useful for prevention and/or treatment of diseases associated with Clostridium difficile. Furthermore, the synthetic saccharide of general formula (I) is useful as marker in immunological assays for detection of antibodies against Clostridium difficile bacteria.

The present disclosure provides, among other things, a single-dose vaccine composition that includes a chitosan adjuvant and HPV virus-like particles (VLPs) of at least one type of human papillomavirus (HPV) selected from the group consisting of HPV types: 6, 11, 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 55, 56, 58, 59, 66, 68, 73, and 82, where the single-dose vaccine composition provides enhanced or comparable HPV vaccine response in comparison to a similar multiple-dose vaccine formulated without such chitosan adjuvant.

The present application is generally directed to novel pneumococcal polypeptide antigens and nucleic acids encoding such antigens, and immunogenic compositions comprising such antigens for treating and preventing pneumococcal infection. The present invention further provides method of using the antigens to elicits an immune response (e.g., IL-17A response, a T cell-mediated and/or B-cell-mediated immune responses). The present invention also provides methods of prophylaxis and/or treatment of pneumococcal-mediated diseases, such as sepsis, comprising administering an immunogenic composition including one or more of a combination of pneumococcal antigens or functional fragments thereof as disclosed herein. In some embodiments, one or more pneumococcal antigens can be present in a polysaccharide conjugate. The compositions induce an anti-pneumococcus immune response when administered to a mammal. The compositions can be used prophylactically to vaccinate an individual and/or therapeutically to induce a therapeutic immune response to an infected individual.

The present invention refers to new glycoconjugate antigens expressing built-in multiple epitopes and to polyvalent glycoconjugate vaccines intended for the protection of mammalians, and particularly for the protection of the human population from enteropathogenic bacteria, such as the Gram-positive anaerobic bacterium Clostridium difficile and the Gram-negative bacteria Salmonella typhi, Escherichia Coli, Vibrio Cholerae, Shigella flexneri, Salmonella typhimurium, Salmonella enteritidis, Salmonella paratyphi A, Shigella sonnei, Shigella dysenteriae, Salmonella cholerasuis, Klebsiella, Enterobacter, Pseudomonas aeruginosa and/or from viral gastrointestinal infections due to human noroviruses.

The present invention provides a fusion polypeptide that induces a humoral immune response and a cellular immune response to a virus, containing antigens or fragments thereof of the following (a) and (b), and having an oligomerization activity: (a) an antigen of the virus or a fragment thereof containing a B cell epitope conserved among subtypes of the virus; and (b) an antigen of the virus or a fragment thereof containing a T cell epitope conserved among subtypes of the virus (wherein the antigen(s) or the fragment(s) thereof of (a) and/or (b) have an oligomerization activity, or the fusion polypeptide further contains (c) a polypeptide having an oligomerization activity in addition to the antigens or the fragments thereof (a) and (b)).

A method for synthesizing influenza virus-like particles (VLPs) within a plant or a portion of a plant is provided. The method involves expression of influenza HA in plants and the purification by size exclusion chromatography. The invention is also directed towards a VLP comprising influenza HA protein and plant lipids. The invention is also directed to a nucleic acid encoding influenza HA as well as vectors. The VLPs may be used to formulate influenza vaccines, or may be used to enrich existing vaccines.

The invention provides improved staphylococcal antigens. Immunogenic compositions are also provided. The invention may find use in the prevention and treatment of staphylococcal infections.

Described herein are CpG-adjuvanted SARS-CoV-2 vaccines and compositions and methods of producing and administering said vaccines to subjects in need thereof.

Provided are a tumor immune enhancer, a pharmaceutical composition thereof, and a preparation method therefor. The enhancer comprises one or more polypeptides using sequences shown in SEQ ID NOs.: 1-9 as core structures, and can be used for preparing tumor vaccines.

Computational prediction of immunogenic epitopes is a promising platform for designing therapeutic and preventive vaccines. A potential target is, for example, the human immunodeficiency virus (HIV-1) for which, despite decades of efforts, no vaccine is available. Indeed, due to the enormous variability of the virus, a single formulation effective against all or most HIV strains might not be achievable. Moreover, upon infecting host cells, HIV-1 can integrate in the host genome and form long lasting latent reservoirs that are not susceptible to common antiretroviral treatments. Therefore, a therapeutic vaccine designed to eliminate infected cells might represent a key component of strategies aimed at curing the infection. We herein introduce an automated algorithm to produce personalized and population-based vaccines.