Described is a vaccine composition comprising an effective amount of at least one polypeptide selected from the group of IdeSsuis, rIdeSsuis, an analogue or a fragment thereof, or a polynucleotide encoding the same. This vaccine composition is used in the prophylactic, metaphylactic or therapeutic treatment of a Streptococcus suis infections in pigs or humans.

A polypeptide mimicking epitope of glycoprotein gp120 of HIV-1 virus that is recognized by a paratope of broadly neutralizing antibody VRC01 and has the length up to 100 amino acid residues and contains an amino acid sequence:

TABLE-US-00001 (SEQ ID NO. 1): X.sup.1YKNX.sup.2INX.sup.3AX.sup.4X.sup.5VX.sup.6X.sup.7VKRX.sup.8IDX.sup.9ILAX.sup.10LP X.sup.1 is selected from amino acids A, N, R; X.sup.2 is selected from amino acids A, R, D; X.sup.3 is selected from amino acids R, V, P; X.sup.4 is selected from amino acids V, L, S; X.sup.5 is selected from amino acids T, G, R; X.sup.6 is selected from amino acids G, T; X.sup.7 is selected from amino acids L, A; X.sup.8 is selected from amino acids V, I; X.sup.9 is selected from amino acids G, A, R; X.sup.10 is selected from amino acids R, A, G;
with a directly attached alpha-helical structure at the N-terminus or C-terminus is disclosed.

The invention relates to an immunogenic or vaccine composition against the 2019 novel coronavirus (SARS-CoV-2), comprising a nucleic acid construct encoding a SARS-CoV-2 coronavirus Spike (S) protein antigen or a fragment thereof comprising the receptor-binding domain, wherein the nucleic acid construct sequence is codon-optimized for expression in human.

Aspects of the disclosure relate to methods for producing an antigen-specific immune response to human cytomegalovirus (hCMV) in a subject by administering mRNA vaccines.

Disclosed herein include methods, compositions, and kits suitable for use in vaccination. There are provided, in some embodiments, nucleic acid compositions (e.g., mRNA vaccine, DNA vaccine) comprising a polynucleotide encoding a fusion protein. The fusion protein can comprise an antigenic polypeptide (AP) and an endosomal sorting complex required for transport (ESCRT)-recruiting domain (ERD). A plurality of fusion proteins can be capable of self-assembling into an enveloped nanoparticle (ENP) secreted from a cell in which the fusion proteins are expressed. There are provided, in some embodiments, populations of ENPs.

Provided is a vaccine composition including a recombinant DNA vaccine against a pathogen. The recombinant DNA vaccine includes an expression cassette operably linked to a promoter, and the expression cassette encodes a non-structural protein of a Sindbis virus and an antigenic protein of the pathogen. Also provided is a method of producing a protective immune response against a pathogen in a subject in need thereof by administering the vaccine composition to the subject.

Described herein is a method for cancer immunotherapy by administering to a subject an mRNA vaccine designed to express the carbonyl terminal segment of human chorionic gonadotropin (hCG). Also described an improved adjuvant by co-administration of an antisense IL-10 molecule to shift the vaccine immune response to enhanced T-cell responses to hCG. Other embodiments relate to devices and methods for improved delivery of the mRNA vaccine and adjuvant. The intended use involves repeated administration of the vaccine components to subjects over an interval of several months in a repeated boosting strategy.

A polypeptide comprising the sequence of SEQ. ID NO. 2, 3, 4, 7 or 8. The polypeptide may have the sequence of an immunogenic fragment thereof comprising at least eight amino acids, wherein the immunogenic fragment is not one of SEQ. ID NOS. 6 or 11 to 16. The polypeptide may have a sequence having at least 80% sequence identity to the aforementioned polypeptide or immunogenic fragment. The polypeptide is less than 100 amino acids in length and does not comprise the sequence of any of SEQ. ID NOS. 10, 46, 56, 57 or 59 to 62 and does not consist of the sequence of SEQ ID NO. 58. The polypeptide is useful in the treatment or prophylaxis of cancer.

The present disclosure provides particles for delivering a nucleic acid that encodes an immunogenic peptide in an antigen presenting cell. The disclosed particles can function as a vaccine and can be used to treat or prevent a viral or bacterial infection in a subject by expressing in vivo an immunogenic peptide, thereby stimulating the subject's immune system to attack the virus or bacteria that naturally express the immunogenic peptide.

The present invention relates to RNA, particularly an immunostimulatory RNA (isRNA), a coding RNA or a combination thereof, for use in the treatment or prophylaxis of a disease, in particular a tumor and/or cancer disease. The present invention also provides pharmaceutical compositions, and a kit comprising the RNA(s). Further, the invention also comprises medical uses of the RNA(s) and compositions comprising the RNA(s).