Definition of IgG and IgM

Immunoglobulins are molecules that intervene in the defense processes against microorganisms, foreign cells and also against substances capable of producing allergies. They are commonly known as antibodies.

Different types of immunoglobulins are produced in the body, each one is specific against a certain antigen. This is what allows a memory immunological, which is obtained when coming into contact for the first time with a certain microorganism, or when it is vaccinated, causing that once a certain disease infectious it does not reappear.

Some examples of immune memory are diseases such as measles, chicken pox, and rubella.

There are five types of immunoglobulins: A (IgA), G (IgG), M (IgM), E (IgE) and D (IgD)

The A, E and D are those that are produced in less quantity and are related to local defenses at the level of the mucous membranes of the respiratory tract and the apparatus digestive, as well as allergic-type responses.

For their part, My G they are related to the defense of the organism against microorganisms.

Antibodies are present mainly in the blood, in secretions such as saliva and tears, as well as attached to the surface of B lymphocytes, which are the cells of the immune system responsible for producing the antibodies.

Functions of immunoglobulins G and M

Once a microorganism or a cell foreign to the body, the immune system is activated.

If it is the first time that this agent comes into contact with the immune system, the Ig M, which is the first type of antibody to be produced against a certain microorganism, this lasts on average about three weeks and then disappears. Once the initial attack against the foreign agent has been carried out, it begins to occur the Ig G, this has a duration forever so it is the one that provides permanent protection against this disease.

Ig G is specific for each microorganism, there are as many types of Ig G as there are microorganisms with which it has come into contact throughout life. For this reason, this is the type of antibody that we have in higher concentrations in the blood.

Once the immunoglobulins bind to the cells recognized as foreign, they are able to activate a special type of attack against external investors that is the system of complement. This consists of a series of protein different that are activated in a cascade to finally produce the rupture of the cells and therefore their death.

How to interpret IgG and IgM results

They can be determined by examinations carried out in a show of blood. In general terms, the results can be interpreted as follows:

Positive IgM with negative IgG: We are in the presence of an acute infection.

Negative IgM with positive IgG: The person has already developed an infection by this microorganism at some point in his life, but it cannot be established when.

Positive IgM with positive IgG: It means that the person had an infection in the past and that they came into contact with the microorganism again, that is, they have a re-infection.

Negative IgM with negative IgG. The person does not have the infection by a certain microorganism at the present time nor has he had it in the past.

Photo: Fotolia - designua

Subjects in IgG and IgM