Tissue transplantation organ rejection types

Even if tissue types are dosely matched, transplanted organs are usually rejected unless preventive measures are taken. Rejection, if it occurs, can begin soon after transplantation - acute rejection - but can... 

Aging (skin and other tissues), myocardial infarct or stroke, inflammation, rheumatoid arthritis, atherosclerosis, pulmonary disorders (asthma and chronic obstructive pulmonary diseases), radiation injury, organ transplant rejection, psoriasis, hypertension, AIDS, multiple types of cancer, neuro-degenerative diseases (Parkinson s), diabetes, muscular dystrophy... 

In order to fully understand the complex biochemical mechanisms by which the thymus and its hormones control the expression of immunity, it is first necessary to review briefly the organization of the thymus-dependent (T cell) immune system (Fig. I). The predominant cells of the peripheral lymphoid tissue (i.e., spleen, lymph nodes) includes both B and T lymphocytes. In the presence of foreign antigens, B lymphocytes differentiate into plasma cells, which in turn synthesize antibody thus, B cells make up the humoral arm of the immune system. In contrast, T lymphocytes are responsible for mediating all the classical cellular immune responses such as delayed type hypersensitivity skin responses, organ transplant rejections, and sensitized antitumor immunity as well as immunity toward various viral, fungal, and protozoal pathogens (Reinherz and Schlossman, 1980). 

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