Thymomodulin Warning

As this issue went to press, a reader in Germany called to
tell us that the German Ministry of Health had warned people
not to use calf thymus or other organ extracts (widely used
in Europe in cancer treatment), because of a theoretical risk
of contamination with BSE (bovine spongiform encephalopathy,
also called "mad cow disease"), which has killed over 100,000
cattle in England. The warning was broadcast in a television
report in late June or early July.

Thymomodulin, covered in our last issue, is a calf thymus
extract. The warning does not apply to synthetic thymic
hormones, such as TP-5 or thymosin alpha 1, which are not
made from animal thymus glands.

BSE has been a major issue in Europe, where there has been
much controversy over the safety of eating British beef. The
cattle are believed to have acquired the infection through
meat from sheep which was used in their feed. That feed has
been banned for several years, so it had been assumed that
meat and organs from calves were safe. But in February 1994,
British agricultural officials confirmed that a calf born in
1989, a year after the feed ban, had the disease, raising
safety questions again.

Apparently no person is known to have been infected with BSE.
But laboratory animals have been infected, and some experts
suspect that BSE may be the same as Creutzfeldt-Jakob
disease, a rare but fatal condition in humans. A proposed
German ban on the import of British beef has led to a
diplomatic dispute between the countries.

The U.S. public is largely unfamiliar with this issue because
the press has mostly ignored it, carrying only about two
percent of the number of articles published in the British
press.

Comment

It is hard to judge how serious this risk (if any) may be.
The controversy has been around for years, and manufacturers
have adopted precautions, such as only using animals from
areas free of BSE. Persons considering using thymus extracts
should be aware of the warning.