History
It was first mentioned by the US Taxonomoist Murrill in the (Index of Fungi, 1947, pg. 16).
In 2002 Wasser, Didukh (Intl J Med Mush 4:267-290) discovered this species to be identical to the already known Agaricus brasiliensis.

Commercial use
Due to its high content of beta glucan, higher than both Reishi and Shiitake mushrooms, Agaricus subrufescens is used in oncological therapy, mainly in Japan and California. It has been commercially cultivated in Asia and South America since 1993. Because of this valuable polysaccharide, and lack of supply, Agaricus blazei is relatively expensive.
Agaricus blazei mushroom specifically helps in production of interferon and interleukin, which are instrumental in fighting off cancer cell metastasis, especially cancer of the uterus. It also reduces blood glucose, blood pressure, cholesterol levels, and the effects of arteriosclerosis.
The Beta Glucan found in ABM is actually three different substances:
1. Beta-(1-3)-D-glucan
2. Beta-(1-4)-a -D-glucan
3. Beta - (1-6)-D-glucan

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