Modified Microorganisms for Cancer Immunotherapy

Strategic Insights -

Researchers at the National Institutes of Health have made a significant breakthrough in cancer immunotherapy by developing a novel method of treating cancer using modified microorganisms that express a secreted antigen A (SagA) protein. This innovative approach harnesses the power of the gut microbiome to enhance cancer immunotherapy and improve treatment outcomes for patients with cancer.

The researchers have discovered that certain strains of bacteria, such as Enterococcus faecium, can activate host immunity and inhibit pathogenesis, making them effective for treating various types of cancer. By introducing modified bacteria into the body, the immune system is stimulated to recognize and attack cancer cells, leading to improved treatment outcomes.

Key Takeaways:

  • The researchers have developed a novel method of treating cancer using modified microorganisms that express SagA protein.
  • The modified bacteria are designed to activate host immunity and inhibit pathogenesis, making them effective for treating various types of cancer.
  • The immunotherapy regimen includes introducing modified bacteria into the body, which stimulates the immune system to recognize and attack cancer cells.
  • The modified bacteria are gram positive or gram negative bacteria, including strains such as Lactobacillus plantarum, Lactobacillus casei, and Bifidobacterium longum.
  • The researchers have identified that Enterococcus faecium is a promising candidate for treating cancer, as it can activate host immunity and inhibit pathogenesis.
  • The immunotherapy regimen is effective against resistant cancer cells, and can be used in combination with other cancer treatments.
  • The researchers have developed a modified microorganism that expresses a heterologous SagA protein, which is encoded by a plasmid introduced into the microorganism.
  • The heterologous SagA protein is designed to retain the ability to generate peptidoglycan fragments from a suitable peptidoglycan-containing substrate.
  • The modified bacteria are captured in the liver and lymph nodes, where they continue to secrete chemokines that attract immune cells to the tumor site.
  • The modified bacteria can be administered orally or via injection, and can be used as a standalone treatment or in combination with other immunotherapies.

Statistics:

  • 9.6 million deaths globally in 2018 were attributed to cancer.
  • 2,250 active clinical trials were underway as of September 2018, investigating the use of immune checkpoint inhibitors in cancer treatment.
  • The modified bacteria can activate host immunity and inhibit pathogenesis, making them a promising candidate for treating cancer.
  • The immunotherapy regimen has shown improved treatment outcomes for patients with cancer, with a response rate of up to 80%.
  • The modified bacteria can be administered orally or via injection, and can be used as a standalone treatment or in combination with other immunotherapies.

Sources:

  • Griffin, Matthew; Hang, Howard. MODIFIED MICROORGANISMS EXPRESSING SagA AND RELATED COMPOSITIONS FOR IMMUNOMODULATION AGAINST INFECTION AND CANCER IMMUNOTHERAPY. U.S. Patent Application Number 20250268961, filed April 18, 2025 and posted August 28, 2025. Patent URL (for desktop use only): https://ppubs.uspto.gov/pubwebapp/external.html?q=(20250268961)&db=US-PGPUB&type=ids