Antibodies to alpha5beta1 and alpha(v)beta3 integrins react with Candida albicans alcohol dehydrogenase.

It has been hypothesized that Candida albicans possesses integrin-like receptors on its cell surface. This is because C. albicans binds numerous fluid-phase extracellular matrix (ECM) proteins on its cell surface and adheres to the same ECM proteins when immobilized. In addition, numerous antibodies to human integrins (receptors for ECM proteins) bind to the fungal cell surface and in so doing inhibit the binding of the respective proteins. To demonstrate the presence of such a cell surface integrin, a cDNA library of C. albicans yeast cells was screened with polyclonal antiserum to the human fibronectin receptor (alpha5beta1 integrin). Clones isolated by this screening technique also reacted specifically to antiserum against the human vitronectin receptor (alpha(v)beta3 integrin). DNA sequence analysis of the cloned insert predicted a 350 aa protein (37 kDa). This predicted protein showed 75% homology at the nucleotide sequence level to alcohol dehydrogenase (ADH) of Saccharomyces cerevisiae. In vitro transcription/translation of the cloned inserts yielded a 37 kDa protein that was immunoprecipitated with antibodies to the alpha5beta1 and alpha(v)beta3 integrins and an antibody to a C. albicans fibronectin receptor. These antibodies and an mAb to the human vitronectin receptor demonstrated an antigen of -37 kDa present in the cell-wall preparations of C. albicans and in spent growth medium. All four antibodies reacted with authentic ADH. The possible significance of these results in relation to C. albicans adherence is discussed.

The fibronectin adhesin of Candida albicans.

Candida albicans possesses on its cell surface an adhesin which binds the whole viable fungus to subendothelial extracellular matrix and matrix proteins. The adhesin is composed of 75 to 80% carbohydrate and approximately 20 to 25% protein by weight. High-performance liquid chromatography of material eluted from a fibronectin-agarose affinity column demonstrates the presence of three peaks, all of which on sodium dodecyl sulfate-polyacrylamide gel electrophoresis show the presence of one protein of approximately 60 kDa. Molecular weight sizing column chromatography, however, demonstrates that the adhesin elutes with an apparent molecular mass of 42 kDa. The N terminus of the 60-kDa glycoprotein is blocked to Edman degradation. The fibronectin adhesin of C. albicans is a glycoprotein that may be present and functional as an aggregate or multimer of a 60-kDa protein.

Prostatic fluid lactic dehydrogenase isoenzyme patterns of prostatic cancer and hyperplasia.

LDH isoenzyme patterns were determined in prostatic fluid from 286 patients with a prostate gland judged to be normal, the site of benign hyperplasia on clinical evidence or the site of benign hyperplasia or carcinoma on the basis of histologic evidence. Fluid from 12 of 15 patients (80 per cent) with carcinoma representing all stages and grades of disease showed an LDH-V/I ratio of more than 3. This ratio was exceeded in only 6 of 57 (11.8 per cent) and 14 of 97 (14.4 per cent) patients in whom the diagnosis of benign prostatic hyperplasia without evidence of infection was established histologically or clinically, respectively. An LDH-V/I ratio exceeding 3 was seen commonly in patients with a diagnosis of benign prostatic hyperplasia with a recent history suggesting infection and more than 10 WBCs per high power field on microscopic examination of the prostatic fluid. These observations suggest that an LDH-V/I ratio exceeding 3 in the prostatic fluid in the absence of a history of infection and more than 10 WBCs per high power field on microscopic examination should be regarded as an indication of a high risk of the presence or development of a malignancy of the prostate. The results obtained also support the concept that, in the presence of malignancy, expressed prostatic fluid provides an adequate sample of cells with altered metabolism.