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The objective of the present work was to set up a routine test adapted to screening for antiendothelial cell antibodies (AECAs) in serum samples with minimal interference from antinuclear antibodies (ANAs) or rheumatoid factors (RFs). We compared the titers of AECAs titrated following two enzyme-linked immunosorbent assays (ELISAs): (i) an ELISA with ethanol-fixed EA.hy926 monolayers as the antigenic substrate and (ii) an ELISA with nucleus-depleted lysates prepared from EA.hy926 cells and normalized for protein (1.0 to 1.7 mg/ml) and DNA (< or =0.1 microg/ml) contents as a surrogate substrate (postnuclear supernatant ELISA [PNS-ELISA]). The AECA titers in 51 serum samples, including 28 samples containing ANAs, were compared. A significantly positive correlation (r = 0.77; P < 0.001) between the two series was shown only for the ANA-negative serum samples. Conversely, ANAs or RFs in samples were shown not to interfere in tests for AECAs by the PNS-ELISA. AECAs recognize their antigenic targets in postnuclear supernatants, which is representative of the endothelial antigenic content, with improvement of the reliability of the assay, a prerequisite to application of the assay for their evaluation in clinical practice.

During infection by human immunodeficiency virus (HIV), oral pseudomembranous candidiasis frequency is high. Adherence of Candida albicans to epithelial cells constitutes one of the first step in the setting up of candidiasis. Adherence ability of Candida albicans to buccal epithelial cells (BEC) is estimated for 83 isolates. The yeasts are isolated from buccal swabs from HIV+ patients with clinical oropharyngeal candidiasis. Results show that Candida albicans ability to adhere to BEC is variable within isolates; it appears that most of the isolates are weakly adherent. In addition, adherence is not correlated with the serotype A or B of yeasts. We do not either observe any correlation between adherence capacity and sensibility of yeasts to fluconazole. Moreover, no correlation is observed between a group of 13 genetically identical isolates (analysed on 21 loci with isoenzymes method) and their adherence to BEC. Finally, Candida albicans virulence, which is studied in vivo on intravenously infected mouse model, does not seem to be correlated with capacity of each yeast to adhere on BEC in vitro.