Immunoglobulin A only weakly. IgA exists in two isotypes, IgA1 and IgA2. They are both heavily glycosylated proteins. While IgA1 predominates in serum (~80%), IgA2 percentages are higher in secretions than in serum (~35% in secretions); the ratio of IgA1 and IgA2 secreting cells varies in the different lymphoid tissues of the human body: Both IgA1 and IgA2 have been found in external secretions like colostrum, maternal milk, tears and saliva, where IgA2 is more prominent than in the blood. Polysaccharide antigens tend to induce more IgA2 than protein antigens. Both IgA1 and IgA2 can be in membrane-bound form. ("see B-cell receptor")
Infant nutrition formula-fed. Colostrum is a great source of nutrition for a newborn baby, it is a thick yellow fluid that a mother first produces after birth. It has valuable nutrition that aids the baby with building immunity because it helps destroy disease-causing viruses. Other benefits of colostrum include: prevention of jaundice, aiding the baby in passing their first stool, building a strong immune system, providing a great number of vitamins and protein, and prevents low blood sugar in babies. Overall, the sticky, thick, yellow liquid called colostrum has many benefits for a newborn baby which can be only provided to the