The term ZBA (Zero Balance Account) is sometimes used to describe a transit account. In reality, ZBAs are a completely different story and are usually used in an acquiring and merchant account context, where one party opens the account and another sweeps (clears) it daily.
Helper T cells are the major driving force and the main regulators of the immune defense. Their primary task is to activate B cells and killer T cells. However, the helper T cells themselves must be activated.
Lymphocytes of specific immunity T cellsâincluding the subclasses helper T cells and killer T cellsâand B cells. The recipient's helper T cells coordinate specific immunity directed at the donor's self peptides or at the donor's Major histocompatibility complex molecules, or at both.