A vércsoport antitestek (A,B) mikor kerülnek a vérbe?

Az AB0 vércsoport antitestjei már kisgyermekkorban (kb. 3-6 hónapos kor körül) elkezdenek termelődni. Ez azért van, mert egyes baktériumok antégiénjei nagyon hasonlítanak az A illetve a B antigénekhez.

"The antibodies develop between 3 - 6 months of age due to unknown antigenic stimuli, presumably bacteria and foodstuffs."

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"They are produced in response to environmental stimulants, such as bacteria, and are therefore termed naturally occurring antibodies. Antibody production begins after birth and is usually detected by 4–6 months of age, reaches a peak at age 5–10 years, and then declines with increasing age."

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"ABO antibodies in the serum are formed naturally. Their production is stimulated when the immune system encounters the "missing" ABO blood group antigens in foods or in micro-organisms. This happens at an early age because sugars that are identical to, or very similar to, the ABO blood group antigens are found throughout nature."

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