Dendritic cells: what are they, what are their functions and main types

Dendritic cells (DC) are cells produced in the bone marrow that can be found in blood, skin and in the digestive and respiratory tract, which form part of the immune system and are responsible for identifying the infection and developing the immune response.

In this way, when the immune system feels threatened, these cells are activated with the objective of identifying the infectious agent and promoting its elimination. Therefore, if the dendritic cells do not function properly, the immune system makes it more difficult to defend the organism, with a greater probability of developing a disease and even cancer.

Function of dendritic cells

Dendritic cells are responsible for capturing the invading microorganism and presenting antigens that are available on their surface to T lymphocytes, initiating the immune response against the infectious agent, fighting the disease.

Due to the ability to capture and present the antigens on their surface, which are part of the infectious agent, dendritic cells receive the name of Antigen Presenting Cells or APC.

In addition to promoting the first immune response against a certain invading agent and guaranteeing innate immunity, dendritic cells are essential for the development of adaptive immunity, which is the one in which memory cells are generated, preventing it from happening again in a different way. lighter, the infection by the same microorganism.

Understand how the immune system works.

Types of dendritic cells

Dendritic cells can be classified according to their migration characteristics, expression of markers on their surface, location and function they perform. In this way, dendritic cells can be classified mainly into the following types:

• Plasmacytoid dendritic cells, are located mainly in the blood and in lymphoid organs, such as the spleen, thymus, bone marrow and lymph nodes. These cells act especially against viruses due to their ability to produce interferon alpha and beta, which are proteins responsible for the regulation of the immune system, as well as having antitumor properties in some cases, in addition to their antiviral capacity.

• myeloid dendritic cells, They are located in the skin, blood and mucosa. Cells located in the blood receive the name of inflammatory DCs, which produce TNF-alpha, which is a type of cytokine responsible for the death of tumor cells and for the inflammatory process. In tissue, these cells can receive the name of interstitial or mucosal DC and when they are present in the skin, they are called Langerhans or migratory cells, and after their activation, they migrate through the skin to the lymph nodes where they present the antigens to the T lymphocytes.

The origin of the dendritic cells continues to be studied, but it is considered that it may have the origin of both a lymphoid and myeloid lineage. In addition, there are two theories that try to explain the origin of these cells:

1. Functional Plasticity Modelwhich considers that the different types of dendritic cells represent different stages of maturation of a single cell line, with different functions as a result of the location where they are present;

2. Specialized Lining Modelwhich considers that the different types of dendritic cells are derived from different cell lines, this being the reason for their different functions.

Both theories are believed to be grounded and in the organism, and it is probable that the two theories succeed simultaneously.

How can you help treat cancer

Due to its fundamental role in the immune system and the ability to regulate all processes related to immunity, studies have been carried out with the objective of verifying its effectiveness in the treatment against cancer, mainly in the form of a vaccine.

In the laboratory, dendritic cells are placed in contact with samples of tumor cells and their ability to eliminate cancer cells is verified. In case the effectiveness of the results of the findings in experimental and animal models is verified, it is possible that the results of the vaccine against cancer with dendritic cells may be available for the population. Despite being promising, more studies are needed for the development of the vaccine, as well as for the type of cancer that this vaccine would be able to fight.

In addition to being able to be used against cancer, the application of dendritic cells has also been studied in the treatment against AIDS and systemic sporotrichosis, which are serious diseases and lead to the reduction of the immune system. See some ways to improve and strengthen the immune system.