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")
A Man Called Hawk hair and shaved his goatee, as a means of distinguishing his character Benjamin Sisko from Hawk. However, the goatee was added to Sisko's look near the end of Season 3, and his head was permanently shaven at the start of Season 4. Also on "Deep Space Nine", Sisko's old friend and mentor, Dax, was called 'Old Man' by Brooks' character. The TV One network resumed airing episodes of "A Man Called Hawk" in September 2006. A Man Called Hawk A Man Called Hawk is an American action drama series that ran on ABC from January 1989 until May 13, 1989.