Which immunoglobulins are in breast milk?

The Immunoglobulins in Breast Milk: A Vital Component of Infant Immunity
Breast milk is often heralded as the gold standard for infant nutrition, but its benefits extend far beyond mere sustenance. One of the most critical aspects of breast milk is its rich content of immunoglobulins, which play a pivotal role in protecting newborns from infections and aiding in the development of their immune systems.
Key Immunoglobulins Present in Breast Milk
The primary immunoglobulin found in breast milk is secretory Immunoglobulin A (sIgA). This antibody constitutes about 10-15% of the total serum IgA and is crucial for mucosal immunity. It acts as a first line of defense against pathogens by binding to viruses and bacteria, preventing them from adhering to and penetrating the mucosal surfaces of the infant’s gastrointestinal tract. This is particularly important as neonates are born with an immature immune system and rely heavily on maternal antibodies for protection.
In addition to sIgA, breast milk also contains Immunoglobulin G (IgG) and Immunoglobulin M (IgM), albeit in smaller quantities. IgG is known for its ability to neutralize toxins and viruses, while IgM is the first antibody produced in response to an infection. The presence of these immunoglobulins in breast milk helps to bolster the infant’s immune response during the critical early months of life.
The Role of Colostrum
Colostrum, the first milk produced after childbirth, is particularly rich in immunological components, including immunoglobulins. It is designed to provide a concentrated source of antibodies and other immune factors, making it essential for newborns. As breastfeeding continues, the composition of breast milk evolves from colostrum to transitional milk and eventually to mature milk, with varying concentrations of immunoglobulins throughout this process.
The Importance of Immunoglobulins
The immunoglobulins in breast milk not only protect infants from infections but also help in shaping and modulating their developing immune systems. This transfer of immunity is vital, as it provides infants with the necessary tools to combat pathogens they may encounter in their environment. Studies have shown that breastfeeding can significantly reduce the incidence of infections, allergies, and other health issues in infants.
In conclusion, the immunoglobulins present in breast milk, particularly sIgA, IgG, and IgM, are essential for providing infants with a robust immune defense. This natural transfer of immunity underscores the importance of breastfeeding in the early stages of life, offering a protective shield that supports the health and well-being of newborns.

Which immunoglobulin is abundant in breast milk?

The most abundant immunoglobulin in human milk is SIgA, which represents over 90% of milk antibodies. However, immunoglobulins G and M (IgM) are also present, but in concentrations much lower than SIgA (9–13).

Which antibodies are present in breast milk?

Of note, immune cells such as B and T lymphocytes, regulatory cells, monocytes/macrophages, neutrophils, natural killer cells and IgA, IgG and IgM antibodies are found in the breast milk (7).

Which immunoglobulin is most abundant in newborns?

Human infants receive the majority of maternal immunoglobulins (Ig), predominantly immunoglobulin G (IgG), via the placenta.

Which immunoglobulins are present in milk?

The primary immunoglobulin in cow colostrum and milk is IgG, whereas the primary immunoglobulin in human milk is IgA [1]. Nevertheless, bovine IgG from colostrum or milk can be effective as a means of providing passive immunity to protect animals and humans from disease.

What immunoglobulin is cow’s milk allergy?

Milk allergy can be either immunoglobulin E (IgE) or non-IgE mediated. IgE-mediated reactions typically occur immediately after ingestion whereas non-IgE mediated are delayed and take up to 48 hours to develop, but still involve the immune system.

What immunoglobulins are in breastfeeding?

In addition, breast milk also contains secretory IgM (SIgM), IgM, and IgG antibodies, but in smaller proportions. Like SIgA, there is selective homing to the mammary gland of plasma cells that produce IgM and IgG, which are subsequently transported into breast milk through pIgR.

What is IgM, IgG, IgA, IgD, IgE?

There are five immunoglobulin classes (isotypes) of antibody molecules found in serum: IgG, IgM, IgA, IgE, and IgD. They are distinguished by the type of heavy chain they contain.

What immunoglobulins are in breast milk?

Although all three major classes of immunoglobulins are present in human colostrum and milk, only IgA and IgM are locally produced in the human mammary gland. These immunoglobulins protect neonates and infants against infection, particularly IgA protects against respiratory tract and gastrointestinal infections.

Which immunoglobulin E is found in breast milk?

The levels of total IgE in breast milk and its fractions were low (<2.4 ng/ml), and those of maternal and infant serum were negligible (18 and 4.3 IU/ml, respectively).

Which immunoglobulin does the fetus get from the mother?

Placental transfer of maternal IgG antibodies to the fetus is an important mechanism that provides protection to the infant while his/her humoral response is inefficient. IgG is the only antibody class that significantly crosses the human placenta.