Pseudomonas Vaccines
Category: Vaccines | Immunology
Vaccines to Combat Pseudomonas aeruginosa Infections in Immunocompromised Patients
from Jennifer M. Scarff and Joanna B. Goldberg writing in Vaccine Design: Innovative Approaches and Novel Strategies
Pseudomonas aeruginosa is an important opportunistic pathogen that causes an array of nosocomial infections, such as ventilator-associated pneumonia and infections in cancer patients. P. aeruginosa infections are difficult to treat with antibiotics, making the need for other therapeutic options, such as vaccination, critical. The main target antigen for vaccines has been the lipopolysaccharide (LPS) of P. aeruginosa and studies show that vaccination may be partially protective, but that a combination of vaccination with either antibiotic treatment or cell transfusion protocols typically works best. The efficacy of vaccination, particularly against LPS, has been investigated in human cancer patients. These patients were capable of mounting an immune response, but it was often short-lived or accompanied by severe side effects. An anti-Pseudomonas vaccine could be beneficial to aid in treatment of nosocomial infections caused by this bacterium, but would need optimization for better efficacy.
Further reading: Vaccine Design: Innovative Approaches and Novel Strategies | Pseudomonas: Genomics and Molecular Biology
from Jennifer M. Scarff and Joanna B. Goldberg writing in Vaccine Design: Innovative Approaches and Novel Strategies
Pseudomonas aeruginosa is an important opportunistic pathogen that causes an array of nosocomial infections, such as ventilator-associated pneumonia and infections in cancer patients. P. aeruginosa infections are difficult to treat with antibiotics, making the need for other therapeutic options, such as vaccination, critical. The main target antigen for vaccines has been the lipopolysaccharide (LPS) of P. aeruginosa and studies show that vaccination may be partially protective, but that a combination of vaccination with either antibiotic treatment or cell transfusion protocols typically works best. The efficacy of vaccination, particularly against LPS, has been investigated in human cancer patients. These patients were capable of mounting an immune response, but it was often short-lived or accompanied by severe side effects. An anti-Pseudomonas vaccine could be beneficial to aid in treatment of nosocomial infections caused by this bacterium, but would need optimization for better efficacy.
Further reading: Vaccine Design: Innovative Approaches and Novel Strategies | Pseudomonas: Genomics and Molecular Biology
Salmonella and Cancer
Salmonella as the paradigm for bacterial therapy of cancer: A progress report
from Robert M. Hoffman writing in Salmonella: From Genome to Function
For over 300 years it has been observed that cancer patients who became infected with bacteria sometimes experienced spontaneous remission of their cancer. Recently, there have been attempts to develop cancer treatments by using tumor-targeting bacteria. Anaerobic microorganisms, such as Clostridium, that preferentially grow in necrotic tumor areas have mostly been used. However, the resulting tumor killing was, at best, limited. Salmonella was originally developed as an antitumor agent by attenuating the bacteria with multiple mutations, including auxotrophs. These multiple auxotrophs appeared to direct the bacteria to the metastatic areas of tumors where more nutrients are available. We have developed a more effective bacterial cancer therapy strategy by targeting viable tumor tissue with Salmonella enterica serovar Typhimurium containing only two auxotrophic mutations. These auxotrophs grow in viable as well as necrotic areas of tumors. However, the auxotrophy severely restricts growth of these bacteria in normal tissue, making this a safe treatment. The S. Typhimurium A1-R mutant, which is auxotrophic for leucine and arginine and had been selected for high antitumor virulence, was effective as monotherapy against human prostate and breast tumors that had been orthotopically implanted in nude mice. The approach described here, where bacterial monotherapy effectively treats primary and metastatic tumors, is a significant improvement over previous bacterial tumor-therapy strategies that require combination with toxic chemotherapy. Exploitation of the tumor-killing capability of Salmonella has great potential for a new paradigm of cancer therapy.
Further reading: Salmonella: From Genome to Function
from Robert M. Hoffman writing in Salmonella: From Genome to Function
For over 300 years it has been observed that cancer patients who became infected with bacteria sometimes experienced spontaneous remission of their cancer. Recently, there have been attempts to develop cancer treatments by using tumor-targeting bacteria. Anaerobic microorganisms, such as Clostridium, that preferentially grow in necrotic tumor areas have mostly been used. However, the resulting tumor killing was, at best, limited. Salmonella was originally developed as an antitumor agent by attenuating the bacteria with multiple mutations, including auxotrophs. These multiple auxotrophs appeared to direct the bacteria to the metastatic areas of tumors where more nutrients are available. We have developed a more effective bacterial cancer therapy strategy by targeting viable tumor tissue with Salmonella enterica serovar Typhimurium containing only two auxotrophic mutations. These auxotrophs grow in viable as well as necrotic areas of tumors. However, the auxotrophy severely restricts growth of these bacteria in normal tissue, making this a safe treatment. The S. Typhimurium A1-R mutant, which is auxotrophic for leucine and arginine and had been selected for high antitumor virulence, was effective as monotherapy against human prostate and breast tumors that had been orthotopically implanted in nude mice. The approach described here, where bacterial monotherapy effectively treats primary and metastatic tumors, is a significant improvement over previous bacterial tumor-therapy strategies that require combination with toxic chemotherapy. Exploitation of the tumor-killing capability of Salmonella has great potential for a new paradigm of cancer therapy.
Further reading: Salmonella: From Genome to Function