# Cyclosporin fungus (Tolypocladium inflatum)

**Tolypocladium inflatum**

**Known today as.** A soil fungus.

Kind: Fungus

## What was it used for?

None, until ciclosporin was found in it.

## What does modern science say?

Its cyclosporin quiets the immune system, and in medical use since 1983 it greatly widened organ transplantation.

## Pharmacognosy and toxicology

- **ciclosporin**: cyclosporin A

**Mechanism.** Ciclosporin binds cyclophilin and so blocks calcineurin, the signal by which T cells are activated; in use since 1983, it greatly widened organ transplantation.

**Dose.** Harms the kidneys and raises blood pressure; blood levels should be checked. St John’s wort rich in hyperforin can halve them.

**Standing.** On the WHO list of essential medicines; isolated in 1971 from a soil fungus gathered in Norway, its immunosuppressive effect found at Sandoz in 1972.

## What lore surrounds it?

Found in a soil sample from Norway that was brought to Switzerland in 1969; Sandoz staff had gathered such samples.

## Sources

- Wikipedia, “Ciclosporin,” en.wikipedia.org (read 2 October 2026).
- Wikipedia, “Tolypocladium inflatum,” en.wikipedia.org (read 2 October 2026).
- Mai, I., et al. (2004). Hyperforin content determines the magnitude of the St John’s wort–cyclosporine drug interaction. *Clinical Pharmacology & Therapeutics* 76: 330–340.
- Borel, J. F., et al. (1976). “Biological effects of cyclosporin A: a new antilymphocytic agent.” *Agents and Actions* 6.

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*Cyclosporin fungus.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-03. The Thinking Press. https://thethinkingpress.org/materia-medica/cyclosporin-fungus

Historical description, not medical advice.