The ability of Candida albicans to adhere to host tissue may well represent an important virulence trait of this opportunistic fungal pathogen. The initiation of lesions at specific tissue locations in the host appears due to specific adherence interactions between adhesins of C. albicans and host cell surface ligands. We and others have found that adhesins appear associated with the phosphomannoprotein of the candidal cell surface. Hydrophilic yeast cells specifically attach to mouse splenic marginal zone macrophages via adhesins that are associated with the glycan portion of the phosphomannoprotein complex. Treatment of yeast cells with β-mercaptoethanol causes release of the fungal adhesin. The adhesin activity is preserved following boiling or digestion with proteolytic enzymes, but is lost following α-mannosidase digestion or periodate oxidation, thus giving support to the mannan nature of the adhesin (s). Hydrolysis of the mannan adhesins by 10mM HCl yields acid-stable and acidlabile moieties, and adhesin sites are associated with both moieties. Adhesin activity in the acid-stable part appears to involve the α-1, 6-linked mannose backbone and the α-1, 2-linked mannosyl side chains. In the acid-labile portion, a β-1, 2-linked tetramannose side-chain shows strong adhesin activity. In related work, we found that specific elimination of macrophages results in increased susceptibility of mice to disseminated candidiasis. In addition, mice induced to make an antibody response against the adhesin preparation are more resistant to disease. Our results indicate that macrophages are important in host resistance against disseminated candidiasis, and we speculate that antibodies specific for mannan adhesins aid in host resistance.

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The C. albicans and S. cerevisiae mannans showed many unique biological effects against mammalian cells in vitro and in vivo through the triggering of interaction between mannan and its receptor. Purified yeast neutral mannan showed antitumor activity against solid type tumor. However, commercial mannans were crude and did not exhibit the antitumor activity. This activity was not influenced by the presence of side chain of mannan but depended on the molecular weight. The neutral mannan showed the lethal activity only in mice; the mechanism was due to the production of PAF and LTC₄ and this activity did not correlate to the virulence of the yeasts. In conclusion, the mannan receptor recognized the macro structure of mannan to express the biological activity, which different from the antibody of micro structure-recognition.

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Recent advance in studies of host defense mechanisms against Candida albicans and Cryptococcus neoformans provides insight into our understanding of immunopathogenetic mechanisms underlying a variety of tissue responses against these yeast-like fungi. In candidiasis fungicidal activity by neutrophils is considered effective for killing hyphal forms of Candida. In contrast, granulomatous response, often seen in cryptococcosis, represents a tissue reaction induced by a specific cellular immunity that is mediated by a battery of cytokines and other inflammatory mediators. Some cryptococcal strains, potentially producing abundant capsular polysaccharide, are prone to induce mucoid cyst-like lesions, which appear to resist phagocytosis and killing by phagocytic cells. Despite the great amount of knowledge accumulated, the precise roles of as yet to be defined inflammatory mediators in the framework of antifungal cellular response still remain to be fully understood. Histopathologic studies, combined with in vitro studies make it easier to gain perspective of the overall immunoregulatory mechanism against these fungal pathogens.

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The present study was done to describe the mechanisms of the hematogenous spread of C. albicans from the lung.
ICR and BALB/c mice were administered anti-cancer drug and adrenocortic steroid hormone intraperitoneally to develop leukopenia of less than 4, 000/mm³. A spore suspension of 2×10⁶ live cells of C. albicans was inoculated intratracheally into non treated and drug-treated mice. The drug-treated animals developed disseminated candidiasis from the lung soon after inoculation. The mechanical destruction of vessel walls by fungi was important for their vascular invasion. The dissemination appeared when the fungal cells invaded into veins of more than 50μm in diameter. On the other hand, no dissemination occurred when the fungal cells entered into capillarys lumens of less than 50μm in diameter, because fibrin thrombi enclosed the cells. The fungal cells were surrounded by the cytoplasm of I type alveolar cells in alveoli of the lung. While the high incidence of dissemination occured by additional administration of heparin, the intraveneous injection of anti-C. albicans antibody after inoculation of C. albicans decreased the incidence of the dissemination.

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The clinical and antifungal effects of topical terbinafine treatment were studied in 24 cases with tinea pedis. The antifungal effects were evaluated by the KOH direct microscopic examination, slant culture, and foot-press culture which showed the dissemination of dermatophytes from the feet. Before the treatment dermatophytes were isolated from 17 cases (70.8%) by the foot-press culture, and from 18 cases (75.0%) by the slant culture. The negative rate of the KOH direct microscopic examination and the rate of clinical improvement were low in the first and second week after the treatment, but the rates of the foot-press culture were very high during this period.
Therefore, it can be concluded that the treatment with topical terbinafine cream reduces relative quickly the dissemination of dermatophytes from the feet of tinea pedis patients.

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An elastolytic proteinase was isolated from Aspergillus fumigatus by column chromatography using diethylaminoethyl (DEAE)-Sephacel, carboxymethyl (CM)-Sephadex C-50 and Mono-S. Homogeneity was confirmed by the formation of a single band after disk polyacrylamide gel electrophoresis (PAGE). This enzyme had a molecular weight of 32, 000 Da as determined by sodium dodecyl sulfate (SDS)-PAGE.
The enzyme activity was inhibited by leupeptin, diisopropyl fluorophosphate (DFP), phenylmethan-esulfonylfluoride (PMSF), α1-antitrypsin, α2-macroglobulin and ulinastatin. However, neither ethylene-diaminetetraacetic acid (EDTA) nor dithiothreitol (DTT) showed any effect on it. This enzyme contained 366 amino acid residues and exhibited an isoelectric point of 9.1. The Aα chain of human fibrinogen was cleaved first, followed later by the Bβ and γ chains.
Elastolytic proteinase from A. fumigatus possesses proteolytic activity as demmonstrated by the hydrolysis of Asn(3)-Gln(4), Gly(8)-Ser(9), Glu(13)-Ala(14), Tyr(16)-Leu(17), Gly(20)-Glu(21), Tyr(26)-Thr(27), and Lys(29)-Ala(30) bonds of oxidized insulin B chain.

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To detect Asp-hemolysin and its mRNA from clinical isolated strains of Aspergillus fumigatus (A. fumigatus), seventeen strains of A. fumigatus including A. fumigatus Fresenius-Muramatsu (FM) as a control were analyzed by Western and Northern blotting procedures. These strains were grown in liquid 199 medium and Sabouraud glucose broth medium. In the Western blot analysis, Asp-hemolysin was detected from the culture filtrate fractions of 12 isolates of A. fumigatus with liquid 199 medium. Northern analysis confirmed Asp-hemolysin mRNA of 0.7kb in 13 isolates of A. fumigatus with liquid 199 medium. These results indicate that, depending on the levels of protein or mRNA, several clinical isolates of A. fumigatus also produce Asp-hemolysin.

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We report a case of acute myeloid leukemia in which multiple nodular subcutaneous abscesses were shown in the extremities after chemotherapy began.
A 47-year-old male was treated with behenoyl-Ara C (BHAC) and daunorubicin (DNR) for acute myeloid leukemia (AML), but the bone marrow suppression continued for a long period and a high grade fever appeared. A month after the anti-leukemic chemotherapy, an abnormal shadow was seen in the right upper lung, and multiple subcutaneous abscesses were observed in the extremities. An abscess was also shown in front of the vertebral body by cervical CT scan. These subcutaneous abscesses were deep-seated in the muscle, and Candida tropicalis was cultured from the extracted tissue. The patient was then treated with fluconazole (FCZ), and five of seven subcutaneous abscesses were extracted. Two months later, the rest of the subcutaneous abscesses and the abscess the lung and vertebral body had disappered.

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Culture filtrate antigens derived from a strain of Aspergillus fumigatus were used in diagnosing aspergillosis, such as aspergilloma, allergic bronchopulmonary aspergillosis and tissue invasive aspergillosis, by the Western immunoblot method detecting the serum specific antibodies, immunoglobulin M (IgM) and immunoglobulin G (IgG). These antibodies in the sera from all patients with those types of aspergillosis were thus detected significantly more clearly than in the healthy, normal controls.
Double diffusion tests using the same antigens were also performed to compare the efficacy of these two methods. In several cases showing negative in the double diffusion test, these antibodies were found to react with proteins possessing the molecular weight of 20, 35, 50, 65 and 73kDa, while in other cases showing positive in the double diffusion test, the antibodies could not be distinguished from each other. We therefore used the Western blotting method to distinguish them.
From the data obtained it was concluded that serologic diagnosis by the detection of IgM and IgG using the immunoblot method plays an important role in strengthening the clinical diagnosis.

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The dermatophyte flora and epidemiological studies on tinea were carried out on outpatients visiting the Department of Dermatology, Gifu University School of Medicine during 1991 and 1992. Results obtained were as follows: 1) 534 cases of tinea, diagnosed by mycological examinations, were found, representing 8% of the total 6, 627 outpatients. 2) The number of cases of tinea was highest in June, July, May and August. 3) Tinea pedis was predominant in patients 50-60 years old, and tinea corporis in the younger or elderly patients. 4) The ratio of TR/TM was 1.4-1.3. A comparison with epidemiological research of 1981 and 1982 showed that the overall number of patients with tinea had dropped, and that of cases of tinea cruris and ungium had decreased; this meant that the cases of tinea corporis had increased in number. Additionally, the ratio of TR/TM was lower than that of 1981 and 1982 (3.0-4.0). Therefore, patient age, types of diseases and dermatophyte flora appear to have changed during the past 10 years.

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