New "criminal evidence" of "net red bacteria" Helicobacter pylori is exposed again!

Helicobacter pylori (H.
pylori) exists in the pylorus of the human stomach.
It is one of the most common bacterial pathogens and is also the only microorganism species known to survive in the human stomach
.

As the "net celebrity bacteria" in the digestive world, Helicobacter pylori is a household name.
In 2005, the two doctors who discovered it, Marshall and Warren, won the Nobel Prize in Physiology and Medicine, and kept it secretive as a "method of murder".
Show the world
.

Recently, a research team led by Professor Dominique Velin from the University of Lausanne, Switzerland once again exposed the malicious behavior of Helicobacter pylori.
They published an article entitled Helicobacter pylori infection has a detrimental impact on the efficacy of cancer immunotherapies in Gut.
The article proves for the first time that infection of the stomach microbe Helicobacter pylori may weaken the effectiveness of cancer immunotherapy
.

In the era of tumor immunotherapy, the most important achievement in cancer treatment is undoubtedly the introduction of immune checkpoint inhibitors (ICIs)
.

Although immune checkpoint inhibitors have shown great potential in the field of cancer treatment, only a small number of patients have shown long-lasting curative effects.
Therefore, improving clinical response and overcoming drug resistance mechanisms have become the main challenges facing this field
.

In order to verify whether Helicobacter pylori can reduce the effectiveness of immunotherapy, the researchers conducted preliminary evaluations of "CTLA4 antibody therapy" and "CTLA4/PD-L1 combination therapy" based on the MC38 colon adenocarcinoma mouse model
.

In addition, the researchers also validated vaccine immunotherapy based on the B16-OVA melanoma mouse model.
They injected CpG-emulsified OVA polypeptide (SIINFEKL) subcutaneously into tumor-bearing mice carrying OVA-specific CD8+ T cells to activate immunity System to achieve the killing effect on tumors.
It was found that H.
pylori infection can also weaken the effect of tumor immunotherapy, but H.
felis, which is also a Helicobacter but lacks virulence factors, has little effect on tumor immunotherapy.

.

H.
pylori infection reduces the effectiveness of cancer immunotherapy in preclinical models

However, it is puzzling whether the weakening effect of H.
pylori on immunotherapy is caused by the change of the fecal microbiota caused by H.
pylori.
In order to find the root, the researchers verified the question based on 16s rRNA sequencing and stool transplantation technology.
The study found that the immunosuppressive effect of H.
pylori-mediated cancer immunotherapy has nothing to do with the intestinal flora
.

The immunosuppression of H.
pylori-mediated cancer immunotherapy has nothing to do with the modification of the fecal microbiota

After determining that H.
pylori itself plays an important role in the immune system, the researchers focused their research on the effect of H.
pylori on the function of the immune system
.

Research data shows that after receiving tumor vaccine immunotherapy, compared with mice not infected with H.
pylori, the total number of OT-1 cells and the number of activated cells in H.
pylori-infected mice declined significantly
.

Helicobacter pylori harms tumor-specific immune response

Finally, the researchers retrospectively analyzed the data of two independent non-small cell lung cancer (NSCLC) patient cohorts to explore the correlation between H.

H.

Note: The original text has been deleted

Reference materials:

[1]https://gut.