IN SITU CULTURES OF DERMATOPHYTES

Abstract

Studies were undertaken to correlate structure with life cycle in four common species of fungi causing skin disease in man. Hairs naturally infected by Microsporon audouini, M. felineum, and Trichophyton gypseum and scutula of Achorion schoenleini were placed, without any nutrient medium, in van Tieghem cells at various humidities controlled by osmotic solutions of known vapor pressure. These fungi, which while parasitizing the animal body produce hyphae and thallospores only, were then found to undergo a second period of growth on the detached infected host tissue in moist atmospheres. During this phase they produced all the highly differentiated spore forms previously known only on various media. The aerial hyphae, aleuriospores, fuseaux and spirals produced by such in situ cultures are described in some detail. It is suggested that in nature the saprophytic phase is initiated when the infected tissues fall from the animal body in a moist situation, and that this phase may have significance in the epidemiology of the disease.

Requirements for the Growth and Sporulation of Trichophyton persicolor

“…The effect of humidity on spore germination was determined by using the technique devised by Davidson & Gregory (1934). Spores of several strains of T .…”

A new method for the study of hair digestion by dermatophytes

“…DAVlDSON &GERGORY (1933 and1934) cultured infected hairs in a moist chamber, van Tieghem cells, and described tile microscopic morphology developed in such cultures to be identical with that developed in culture on Sabouraud's medium. DAVlDSON &GERGORY (1933 and1934) cultured infected hairs in a moist chamber, van Tieghem cells, and described tile microscopic morphology developed in such cultures to be identical with that developed in culture on Sabouraud's medium.…”

The effect of temperature and humidity on the growth of Trichophyton mentagrophytes spores on human stratum corneum in vitro

“…Little is known concerning the moisture requirements of dermatophytes. Davidson & Gregory (1934) placed naturally infected hairs in van Tieghem cells in which the humidity was controlled by sucrose solutions of varying concentrations. The lowest humidity which allowed spore germination was 97^)0 for Microsporum audouini and T. mentagrophytes, ^6% for Microsporum canis and 93% for Trichophyton schoenleini.…”