A monoclonal antibody to a cell wall component of Candida albicans

Abstract

A heterologous fusion between mouse myeloma cells and rat lymphocytes resulted in the isolation of a rat immunoglobulin M monoclonal antibody with both agglutinating and precipitating activity. Indirect immunofluorescence and direct agglutination tests showed that the corresponding antigen was present in the cell wall of the three Candida species considered to be the most pathogenic, C. albicans, C. tropicalis, and C. glabrata, and also in the cell wall of C. guilliermondii. The antigen appeared to be predominantly polysaccharide in nature. Precipitation by counterimmunoelectrophoresis suggested that the epitope is shared by at least two separate molecules with different electrophoretic mobilities. Presence of this epitope varied from strain to strain within a given species and may be related to the morphological stage in the cell cycle. Antigen was shown to be present in the cytoplasm, in the periplasmic space, and at the cell surface of C. albicans. Indirect immunofluorescence also suggested that antigen is excreted from the cell.

Ultrastructural immunodetection of a Pichia anomala killer toxin: a preliminary study

“…Studies have been particularly directed towards pathogenic yeast species to characterize molecules which could be associated with virulence factors secreted along the cellular cycle [5,20]. A monoclonal antibody was used to localize C albicans glycoproteins secreted at the cell surface by immunofluorescence and through the cell wall by ultrastructural immunodetection [14]. Some preferential secretion "ways' were described through the C albicans cell wall characterized by higher concentration of the reacting epitope [2,30].…”

Identification and immunochemical characterization of a germ tube specific antigen of Candida albicans

“…The strategy for immunization which we followed was different from previous studies. The search for specific germ tube antigens defined by monoclonal antibodies is usually undertaken using viable or killed microorganisms [23]. Therefore, most described mAbs are related to carbohydrate moieties and in particular to the cell wall polysaccharide mannan [19,21,22,24].…”

“…Therefore, most described mAbs are related to carbohydrate moieties and in particular to the cell wall polysaccharide mannan [19,21,22,24]. Similar structures were also recognized by rat mAbs [23]. The choice of high responder Biozzi mice did not elicit antibodies of a more restrictive specificity [22].…”

“…It is interesting to note that the expression of some cell surface antigens of C. albicans was variable during morphogenesis of the cells [17][18][19][20]. The epitopes so far identified by mAbs (generally IgM) were generally oligomannosyl residues [18,19,[21][22][23][24] linked to high molecular mass components [19].…”

Rapid identification of medically important yeasts by electrophoretic protein patterns

“…The electrophoretic or antigenic properties of yeast enzymes allowed good species discrimination but the preparation of extracts was time consuming [9,10]. Monoclonal antibodies able to agglutinate blastospores were purified but again were not speciesspecific [11][12][13][14]. DNA probes and DNA fingerprints seemed to be good tools for the differentiation of medically important species but the extrac-tion and purification of the corresponding DNA required about two days [15,16].…”