Live Recombinant Tuberculosis Vaccine
This invention involves live rBCG30 for vaccination in humans and other mammals. However, this recombinant technology can also be used to produce recombinant vaccines overexpressing proteins of varying mycobacterial species. In addition, this invention offers strategies to create TB vaccines for immunocompromised individuals, such as persons with AIDS. Traditional BCG vaccines can cause disseminated disease in patients with weakened immune systems, which may be fatal. The UCLA Researchers have created strains of the TB vaccine whose growth is regulatable or self-limited. Hence, these strains should be safe in immunocompromised patients.
UCLA researchers have developed a more effective TB vaccine utilizing a recombinant BCG strain (rBCG30), which over-expresses a 30-kDa protein, the most abundant protein produced by M. tuberculosis. Animal data have exhibited very promising results. rBCG30 vaccinated animals, when challenged by aerosol with a highly virulent strain of M. tuberculosis, exhibit much less lung, spleen and liver pathology, have ~10 fold fewer lesions, and 10-fold fewer M. tuberculosis organisms in their tissues than BCG-immunized animals. In addition, rBCG30 vaccinated animals exposed to TB infection survived significantly longer than BCG vaccinated groups. The possible virulence of rBCG30 has been compared with BCG, which has a well-established safety profile in humans. rBCG30 vaccinated animals displayed no adverse health effects and had the same rate of vaccine clearance as BCG. Additional safety studies investigating the possibility of genetic exchange between rBCG30 and other bacteria concluded that harmful genetic contamination is unlikely. The concept of inducing a strong protective immune response by immunizing with major extracellular proteins of an intracellular pathogen (of which M. tuberculosis is an example) has been demonstrated in the past in the case of Legionella pneumophila, the agent of Legionnaires disease. Immunization with either one of two major extracellular proteins of L. pneumophila was shown to significantly enhance the survival of animals challenged by aerosol with this pathogen. The findings of UCLAs rBCG30 studies lend further support to the extracellular protein hypothesis, which holds that the major secretory proteins of an intracellular pathogen are potentially highly potent immunoprotective molecules.
Patent Number: US6471967B1
Application Number: US2000550468A
Inventor: Horwitz, Marcus A. | Harth, Gunter
Priority Date: 17 Apr 2000
Priority Number: US6471967B1
Application Date: 17 Apr 2000
Publication Date: 29 Oct 2002
IPC Current: A61K003902 | A61K003904 | A61K0039108 | A61K0039116 | A61K0039118 | A61P003106 | A61P003704 | C07K001435 | A61K003800
US Class: 4242481 | 4240091 | 4240092 | 4241841 | 4241851 | 4241921 | 4242001 | 4242341 | 4353201
Assignee Applicant: The Regents of the University of California
Title: Recombinant intracellular pathogen vaccines and methods for use
Usefulness: Recombinant intracellular pathogen vaccines and methods for use
Summary: (A) are used to prevent infections caused by intracellular bacteria, protozoa, viruses and fungi, in humans or animals, most especially tuberculosis (claimed). (B) can also be used for immunotherapy of these infections. Guinea pigs were immunized intradermally, once, with 1000 colony-forming units (cfu) of Mycobacterium bovis BCG (Connaught) that harbored plasmid pMTB30, expressing the 30 kD major extracellular protein of M. tuberculosis Erdman strain, under control of its own promoter. Nine weeks later, the animals were challenged with 0.1 million cfu of the Erdman strain and after a further 10 weeks the spleen and right lung were analyzed. The mean Erdman strain count (log 10 of cfu) was then 4.53 in the lung and 3.65 in the spleen; compare 5.00 and 4.59 for animals treated similarly with non-transformed BCG. Gross examination of the lung indicated less damage (20% compared with 35%) in animals given the recombinant vaccine.
Novelty: Vaccine against intracellular parasites, useful for preventing tuberculosis, comprises attenuated intracellular pathogen that expresses recombinant antigen
Biomedical
Pathogen
State Of Development Background Related Materials A new vaccine against tuberculosis affords greater survival after challenge than the current vaccine in the guinea pig model of pulmonary tuberculosis. Infect Immun. (2003) Additional Technologies by these Inventors Tech ID/UC Case 23242/2000-377-0 Related Cases 2000-377-0
Recombinant bacillus calmette-guerin (BCG) vaccines expressing the Mycobacterium tuberculosis 30-kDa major secretory protein induce greater protective immunity against tuberculosis than conventional BCG vaccines in a highly susceptible animal model. Proc Natl Acad Sci U S A. (2000)
USA
