Nature: Bacterial peptides on the surface of tumor cells are expected to become a new target for cancer immunotherapy

News March 22, 2021/bioon.
com" target="_blank">/---Cancer immunotherapy may be promoted in an unexpected direction: bacteria residing in tumor cells.
In a new study, researchers from the Weizmann Institute of Science in Israel and their collaborators discovered that the immune system can "see" these bioon.
com/course_video/xi-jun-fei-bian-ma-RNA-de-xi-tong-fa604804.
html">bacteria and show that they can be used to trigger an immune response against bioon.
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html">tumors .
The study may also help clarify the connection between immunotherapy and the gut microbiome, explaining the results of previous studies that the gut microbiome influences the success of immunotherapy.
The relevant research results were published online in Nature on March 17, 2021.
The title of the paper is "Identification of bacteria-derived HLA-bound peptides in melanoma".

bioon.
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Picture from Nature, 2021, doi:10.

1038/s41586-021-03368-8.

In the past ten years, immunotherapy has greatly improved the recovery rate of certain cancers, especially malignant melanoma; but in bioon.
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Professor Yardena Samuels from the Department of Molecular bioon.
com/course/tags/%E7%BB%86%E8%83%9E%E7%94%9F%E7%89%A9%E5%AD%A6/">Cell Biology at the Weizmann Institute of Science has studied molecular "markers"-protein fragments on the cell surface, or peptides, which can mark cancer cells as foreign and may therefore become immunotherapy.
Potential new targets.
In this new study, she and her colleagues expanded the search for new cancer markers to include bioon.
com/course_video/xi-jun-fei-bian-ma-RNA-de-xi-tong-fa604804.
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bioon.
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bioon.
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com/course/tags/%E7%BB%86%E8%83%9E%E7%94%9F%E7%89%A9%E5%AD%A6/">Cell Biology bioon.
com/course_video/chang-fei-bian-ma-RNA-yu-zhong-liu959063.
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Using the method developed by Dr.
Ravid Straussman, Samuels and her team analyzed 17 metastatic bioon.
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They obtained a bioon.
com/course_video/xi-jun-fei-bian-ma-RNA-de-xi-tong-fa604804.
html">bacterial genome map of these tumors , and then used a method called HLA peptidomics to identify bioon.
com/course_video/chang-fei-bian-ma-RNA-yu-zhong-liu959063.
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bioon.
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HLA peptideomics analysis found that there are nearly 300 peptides from 41 different bioon.
com/course_video/xi-jun-fei-bian-ma-RNA-de-xi-tong-fa604804.
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A key new discovery is that these peptides are presented on the surface of cancer cells by HLA protein complexes, which are present on the cell membranes of all cells in our body and play a role in regulating immune responses.
One of the functions of HLA is to "present" foreign peptides to the immune system, allowing immune T cells to "see" them, thereby alerting any foreign matter.
bioon.
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bioon.
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Co-first author of the paper, Dr.
Shelly Kalaora, "said the HLA peptide genomics, we are able in an unbiased manner reveal a tumor antigen peptide HLA presentation.
In the past this approach has enabled us to identify in a bioon.
com/course_video/lin-chuang-shi-yan-de-feng-xian-jian-kong239833.
html">clinical trial manifestations Promising bioon.
com/course_video/chang-fei-bian-ma-RNA-yu-zhong-liu959063.
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” (Bioon.
com)

bioon.
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Reference materials: 1.

Shelly Kalaora et al.
Identification of bacteria-derived HLA-bound peptides in melanoma .

Reference materials: 1.
Shelly Kalaora et al.
Identification of bacteria-derived HLA-bound peptides in melanoma .
Nature, 2021, doi:10.
1038/s41586-021-03368-8.
2.
Study may explain the microbiome-immunotherapy connection
https: //medicalxpress.
com/news/2021-03-microbiome-immunotherapy.
html Identification of bacteria-derived HLA-bound peptides in melanoma