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")
Death Is Called Engelchen Death Is Called Engelchen Death Is Called Engelchen () is a 1963 Czechoslovak war film directed by Ján Kadár and Elmar Klos. It was entered into the 3rd Moscow International Film Festival where it won a Golden Prize. At the end of the Second World War Zlín is liberated by advancing Soviet army. Young Czechoslovak partisan named Pavel was injured in a gunfight with Germans and lies in hospital. He is paralyzed and while recovering, he spends his days by lying on his back. He recalls memories from his life during the war - his experience as a resistance fighter,