or cellular immunity, occur through the T-cell system. On exposure to an antigen, the lymphoid tissues release large numbers of activated T cells into the lymph system. These T cells pass into the general circulation. There are three main groups of T cells: (a) helper. (b) cytotoxic T cells: which attack and kill microorganisms and sometimes the body's own cells.
Organ Donation Day. About Organ Donation Day. Organ Donation Day in India is celebrated on 13th of August every year by the people, government organizations and other related professions in order to motivate normal human beings to donate the organs as well as to understand the value of organ donation in the life of an individual.
1 The kidney is the most commonly transplanted organ. For the first time, the number of patients currently awaiting kidney transplants in the U.S. exceeds 100,000.  Of those on the waiting list, more than one-third will wait three or more years for a transplant.