Anti-lymphocyte globulin

Anti-lymphocyte globulin (ALG) is an infusion of animal- antibodies against human T cells which is used in the treatment of acute rejection in organ transplantation. It was developed in the 1960s, during which time 74 scientific papers were published on its use. Experimental preparations were first used in the Stanford laboratories in heart transplantation, and commercial preparations have been available since the 1970s.

It has also been used in the treatment of aplastic anemia.

It is less commonly used than the similar anti-thymocyte globulin (ATG), and like ATG it is associated with cytokine release syndrome in the short term and an increased risk of post-transplant lymphoproliferative disorder in the long term. ALG is more likely to cause side effects than ATG, but is safer than OKT3.

One notable source of ALG was a horse called Volcano, who lived in South America. At one point in the mid-1990s, the world's entire supply of ALG came from this horse.

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