They are essential in B cell antibody class switching, in the activation and growth of cytotoxic T cells, and in maximizing bactericidal activity of phagocytes such as macrophages. Mature T h cells express the surface protein CD4 and are referred to as CD4+ T cells.Such CD4 + T cells are generally treated as having a pre-defined role as helper T cells within the immune system.hey are essential in B cell antibody class switching, in the activation and growth of cytotoxic T cells, and in maximizing bactericidal activity of phagocytes such as macrophages. Mature T h cells express the surface protein CD4 and are referred to as CD4+ T cells.
To boil artichokes: 1  Fill a large stainless-steel or enameled pot with lightly salted water; bring to boiling. 2  Add artichokes and return water to boiling. 3  Reduce heat; simmer, covered, for about 20 to 30 minutes or until you can easily pull out a leaf from the center of an artichoke.
Bring about 1/2 inch water to a boil in a pan deep enough to hold the artichoke(s) standing up. Add a teaspoon or two of salt (the artichoke will just be sitting it in, not submerged). Set the artichokes in the salted boiling water, cover the pan, reduce the heat to maintain a steady simmer, and cook 20 minutes.