The present invention relates to a method of preparing a live attenuated vaccine by irradiation and a live attenuated vaccine composition prepared by the same, and more particularly, a method of preparing a live attenuated vaccine by irradiation including irradiating a pathogenic microorganism with a dose of 0.5 to 2 kGy of radiation per single radiation six to fifteen times; and a live attenuated vaccine composition including a pathogenic microorganism attenuated to not be revertant to a wild type by generation of at least one mutation of nucleotide insertion and nucleotide deletion by irradiation.

Disclosed herein are immunogenic compositions (e.g., vaccines) for use in the treatment of mycobacteria infections and biomarkers for monitoring of therapeutic responsiveness to the immunogenic compositions in a subject (e.g., a human). In a first aspect, the disclosure features a pharmaceutical composition containing between 1×10{circumflex over ( )}2 CPU and 1×10{circumflex over ( )}10 CPU of a Mycobacterium tuberculosis strain (Mtb) with one or more mutations that ablate or reduce expression of LprG and Rv1410 (ΔLprG Mtb) in a volume of between 0.05 mL and 3 mL.

The disclosure relates to doubly attenuated malaria parasites that have had the functionality of LISP2 and PlasMei2 genes interrupted through genetic manipulation. The double attenuated malaria parasites disclosed herein are useful for methods and compositions for stimulating of vertebrate host immune systems because of the complete cessation of lifecycle progression in the late liver stage, while providing a comprehensive antigenic presentation representing wildtype liver stage parasites. The disclosure also relates to the additional blood stage and gametocyte antigens to compositions of genetically attenuated malaria parasites (GAPs) to enhance efficient immune stimulation and prevention of disease and transmission related to the presence of blood stage parasites.

Methods of treating a Pseudomonas bacterial infection and/or eliciting an immune response in a subject are provided and include administering to the subject a vaccine including a modified Pseudomonas bacterium missing or deficient in alpha-1,3-rhamnosyltransferase and/or one or more other virulence factors. Vaccines comprising a modified Pseudomonas bacterium missing or deficient in alpha-1,3-rhamnosyltransferase are further provided.

Provided herein are methods and compositions related to EVs useful as therapeutic agents.

Disclosed are an attenuation system and the use thereof for attenuating plasmodia, specifically the use of an EF1g gene for attenuating plasmodia. The attenuation system regulates the expression or degradation of the EF1g gene by using a regulatory system, thereby controlling the growth of plasmodia and achieving the attenuation of plasmodia.

Disclosed are a construction method of a recombinant drug-resistant Mycobacterium bovis (M. bovis) Bacillus Calmette-Guerin (BCG) strain and a pharmaceutical composition for treating tuberculosis (TB). The construction method includes: using BCG as an original bacterial strain to construct a drug-resistant BCG strain resistant to at least one selected from the group consisting of STR, LFX, EMB, PRO, PAS, and AMK; and further inserting sequence fragments that can express related antigens Ag85b and Rv2628 causing an immune response into a genome of the strain to construct a recombinant drug-resistant BCG strain. The recombinant drug-resistant BCG strain can compete with Mycobacterium tuberculosis (Mtb) for growth, thereby accelerating the death of Mtb. When used in combination with a drug for treating TB, the recombinant drug-resistant BCG strain can further enhance a therapeutic effect for Mtb, and can also avoid re-infection of a patient.

The present disclosure relates to Salmonella Gallinarum mutant strains and uses thereof. A vaccine composition according to an aspect has no risk of recovering pathogenicity, has no residual pathogenicity due to detoxification of an endotoxin, and does not cause lesions and bacterial re-isolation, thereby exhibiting significantly improved safety compared to the existing fowl typhoid vaccines. In addition, since the vaccine composition induces a high-level immune response even when administered to young chicks, it may be used regardless of age, and as the vaccine strain may be used as a live vaccine having an excellent protective capability by itself, the vaccine composition may be useful for preventing and alleviating fowl typhoid.

The present disclosure provides an attenuated Nocardia seriolae and its construction method and use thereof, which belongs to the technical field of genetic engineering. In the present disclosure, part or all of the glutamate endopeptidase homologue (GluNS) gene sequence of wild-type Nocardia seriolae is knocked out by means of genetic engineering to construct an attenuated strain with the characterized of good protection to the host. The attenuated strain may not only effectively reduce the pathogenicity of the bacteria, but also retain good immunogenicity. At the same time, the attenuated Nocardia seriolae constructed in the present disclosure may also have the characteristics of high genetic stability and may be used as a vaccine candidate strain for the preparation of a vaccine or other biological products for preventing and treating Nocardiosis.

The present invention relates to a method for producing a DNA vaccine for cancer immunotherapy comprising at least the steps of (a) transforming an attenuated strain of Salmonella with at least one DNA molecule comprising at least one expression cassette encoding at least one antigen or at least one fragment thereof; (b) characterizing at least one transformed cell clone obtained in step (a); and (c) selecting at least one of the transformed cell clone(s) characterized in step (b) and further characterizing said at least one selected transformed cell clone. The present invention further relates to a DNA vaccine obtainable by the method according to the present invention.