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.
Trim the tops from the artichokes, then cut in half lengthwise, and place halves into the bowl of lemon water to prevent them from turning brown. Bring a large pot of water to a boil. Meanwhile, preheat an outdoor grill for medium-high heat. Add artichokes to boiling water, and cook for about 15 minutes. Drain. Squeeze the remaining lemon wedges into a medium bowl. Stir in the olive oil and garlic, and season with salt and pepper. Brush the artichokes with a coating of the garlic dip, and place them on the preheated grill. Grill the artichokes for 5 to 10 minutes, basting with dip and turning frequently, until the tips are a little charred. Serve immediately with the remaining dip.