A team of researchers has taken an important step towards a new form of cancer immunotherapy. A two -phase treatment vaccine has demonstrated promising results in stimulating the immune system against cancer cells in preclinical studies, performed on animals.
A new revolutionary vaccine against photo cancer: Pixabay
Our immune system is not only limited to combating bacteria and viruses, acting as a natural barrier against infections, but has the ability to fight cancer.
However, not all tumor cells are easily recognized by the immune system, as they are continuously changes and “camouflage ” To get rid of the body’s natural defense mechanisms, writes News.
To improve treatment, current medical research aims to develop immunotherapy vaccines for patients already diagnosed with cancer.
In these researches, a team from the Department of Gastroenterology, Hepatology, Infectious Diseases and Endocrinology of Hannover Medical School (MHH), which developed a new liposomal vaccine, with a two -stage administration protocol, was involved in these researches.
With this oncological immunotherapy, only two injections administered subcutaneously (under the skin) are sufficient to effectively mobilize the tumor immune system in just 14 days, notes the study, published in the cellular & molecular magazine Immunology.
MHH researchers have been working for 15 years to improve cancer vaccines.
“Dendritic cells are the key factor in triggering the immune response”says Dr. Thomas Wirth.
These cells are part of the innate immune system and constantly scan the body in search of viruses, bacteria and tumor cells. If I recognize structures as foreign or abnormal, they absorb and degrade them, through a natural mechanism of elimination of “intruders”.
As specialized cells that make antigens visible to the immune system, they are able to break down foreign cells into smaller fragments and then display them in the form of peptides on their cellular surface.
These mini-proteins show certain T cells in the acquired immune system how to recognize foreign structures, thus activating a targeted immune response.
In order to achieve this as quickly and efficiently as possible, the researchers opted for a two -phase vaccination protocol. These heterological vaccines involve a two -dose scheme, in which the same antigen is administered twice: a basic dose followed by a booster, each with a different composition.
In this case, a single peptide sequence recognized by the immune system and produced specifically by the tumor cells was sufficient to activate the dendritic cells in the body.
However, since the peptide alone does not trigger a strong enough immune response, the researchers added a so -called agonist – a substance (usually a molecule) that binds to a cell receiver and activates it, by imitating the effect of a natural compound produced by the body.
In other words, an agonist “Encourage” The receiver should trigger a certain biological response, in both phases of vaccination, to further activate the immune cells in the body.
“For primary immunization, we pack peptide with the immune activator in a lipid coating,” explains Dr. Wirth. This determines the dendritic cells in the body to present the tumor antigen of specific T cells, so that they can recognize and attack the tumor.
The liposomal structures used for primary immunization have been developed in a collaboration with the Netherlands.
“At the booster administered after a week, we also add an antibody that acts as an additional stimulator to ensure the ultra-fast multiplication of T cells targeting the tumor,” added Dr. Wirth.
Remarkable improvement of T cell response
The vaccination regime was tested on a rodent replicated model for colon cancer. The effect is amazed even the researchers.
“After only two vaccinations, I noticed an extremely powerful immune response that led to the complete regression of the tumor”notes Dr. Dimitrij Ostroumov from MHH, who led the research with Dr. Wirth.
The experiments of the researchers have shown that liposomal structures can be used effectively for the transport of peptides, and have confirmed a remarkable amplification of the response of T cells, stimulated by the presence of antibodies with an activating effect through the heterological immunization scheme.
The development of the vaccine in a short time and the rapid anti-tumor effect is a considerable gain, and can give, in this way, a survival advantage for people with cancer, say the authors.
An additional benefit of this vaccination regime is its flexibility: the peptide used can be replaced and configured according to the context, offering a personalized approach.
“We can adapt the peptide to the genetic profile of the tumor, and thus produce personalized vaccines, individually adapted to each patient. At the same time, the peptide should not be exclusively a tumor antigen, but can be bearing relevant information for identifying parasites, bacteria or viruses,” concluded Dr. Wirth.
Before the vaccine can be adopted in standard treatments, additional steps are required. The next step is his testing in clinical trials to confirm the effectiveness and safety profile in patients.
