This paper was presented in part at the National Meeting of the Society for Investigative Dermatology, Washington, DC, 30 April 1993.
Antibodies to proteins from Pityrosporum ovale in the sera from patients with psoriasis
Version of Record online: 27 APR 2006
Clinical and Experimental Dermatology
Volume 19, Issue 4, pages 289–293, July 1994
How to Cite
SQUIQUERA, L., GALIMBERTI, R., MORELLI, L., PLOTKIN, L., MILICICH, R., KOWALCKZUK, A. and LEONI, J. (1994), Antibodies to proteins from Pityrosporum ovale in the sera from patients with psoriasis. Clinical and Experimental Dermatology, 19: 289–293. doi: 10.1111/j.1365-2230.1994.tb01197.x
This research was supported by grants from Perez-Companc Foundation, Buenos Aires, Argentina, and Janssen Research Foundation, Belgium. The authors acknowledge the assistance of Dr Alberto Fossati (University of La Plata, Argentina) in the extraction experiments. The Pityrosporum ovale strains were provided by Dr Jan Faergemann (Gotheburg, Sweden).
- Issue online: 27 APR 2006
- Version of Record online: 27 APR 2006
- Accepted for publication 28 January 1994
In order to analyse the humoral immune response to the commensal yeast Pityrosporum ovale, we developed a western immunoblot technique with a salt soluble extract of P. ovale cytoplasm. In the present study, we tested sera from patients with psoriasis (n= 15), seborrhoeic dermatitis (n= 10), pityriasis versicolor (n= 8), and normal controls (n = 10). Seventy-three per cent (11/15) of the patients with psoriasis showed specific reactivity with a protein derived from P. ovale of estimated molecular mass 120 kDa, and 46% (7/15) of the cases recognized a 100-kDa protein. Sera from pityriasis versicolor and normal donors showed nonspecific reactivity with several bands of lower molecular weight.
To characterize the location of the 100 and 120-kDa proteins, we performed a lyticase digestion of the cell wall, and analysed the soluble digested products by western blotting. The sera from psoriasis patients detected several bands in the range 100–120 kDa. The finding of the immunoreactive 120-kDa protein in this fraction suggests its location at the space between cell wail and membrane (periplasmic space).
As a control, we performed an extraction of the cytoplasmic proteins of the dimorphic yeast Candida albicans. C. albicans showed a different pattern of banding in SDS–PAGE. Immunoblots with C. albicans did not allow the detection of any related band. A smear was observed in the high molecular weight range consistent with the presence of lipopolysaccharides.
The role of the immune response in infection by P. ovale has not yet been fully explored. The function of the antibodies recognizing 100-120-kDa bands in the majority of the patients with psoriasis seems to represent a specific immune response to the yeast phase of P. ovale.