Comparison of cytoplasmic extracts of eight Candida species and Saccharomyces cerevisiae

Crossed-line immunoelectrophoresis of cytoplasmic extracts of eight Candida species and Saccharomyces cerevisiae demonstrated the presence of antigens reactive with a rabbit antiserum to a C. albicans extract in all species except C. glabrata. A previously defined major cytoplasmic antigen of C. albicans was also present in C. tropicalis and C. guilliermondii.

Direct activation of human adherent cells by yeast cell wall in vitro

Adherent cells from human peripheral blood could be activated by cocultivation with yeast cell wall for 3 days and the acid phosphatase activity of these cells was elevated. Lymphocyte response to phytohemagglutinin (PHA) was reduced in the presence of yeast cell wall ranging from 0.1 microgram/ml to 1000 micrograms/ml. When the activated adherent cells were added to non-adherent cells or the cells from lymphoid cell line (HD-10), derived from Hodgkin's disease, DNA synthesis of these target cells was suppressed. The supernatants from the activated adherent cells were also inhibitory to the proliferation of the cell line. It is suggested that this in vitro system is useful in investigating the mechanisms of macrophage activation and the roles of macrophages in immune responses.

Opsonic effect of normal and infected human urine on phagocytosis of Escherichia coli and yeasts by neutrophils

The opsonic effect of urine from normal adults and patients with acute cystitis on phagocytosis of yeast and E. coli by purified human neutrophils was investigated. Urine with an osmotic pressure between 200 and 500 mOsm./kg. was the most effective as an opsonic buffer in either phagocytosis of yeast or E. coli by PMN. However, those with an osmotic pressure greater than 500 mOsm./kg. or less than 200 mOsm./kg. were rather suppressive to phagocytosis by PMN. Patient's urine exhibited a more potent opsonic effect on phagocytosis of either bacteria when compared with that of normal urine with a similar osmotic pressure. Heat inactivation gave no effect on the potent opsonic activity of patient's urine, suggesting that complement may not be working in these phagocytosis systems or that the test urine may originally contain no complement. However, immunoelectrophoretic survey of test urine and addition of serum proteins into the urine suggest the possibility that certain serum derived urine proteins other than complement may play an opsonic role in phagocytosis by PMN in the patient's urine, although the factors have not been determined.

Phagocytosis, chemoluminescence, and intracellular killing of fungi by phagocytes from subjects with deficiency of the second component of complement

The capacity of phagocytes from animals or humans with complement component deficiency to ingest and kill Candida albicans has been much disputed. We show that peripheral blood polymorphonuclear leukocytes and mononuclear phagocytes from subjects with hereditary C2 deficiency (C2D) ingested C. albicans or Saccharomyces cerevisiae at an abnormally slow rate. After preincubating C. albicans in C2D plasma, the slow rate of phagocytosis was corrected and subsequent intracellular killing of C. Albicans was normal. A normal number of C2D phagocytes reduced nitroblue tetrazolium after stimulation with either phorbol myristate acetate or ingestion of C. albicans. The rate at which chemoluminescence was generated in response to C. albicans was abnormally slow, but peak chemoluminescence produced by C2D phagocytes in response to C. albicans was normal.

Modulation of polymorphonuclear leukocyte chemiluminescent response to the chemoattractant f-Met-Leu-Phe

Upon the interaction between polymorphonuclear leukocytes (PMNL) and soluble or particulate matter, the cells become metabolically activated and produce chemiluminescence. To respond with chemiluminescence to the chemotactic peptide formyl-methionyl-leucyl-phenylalanine (f-Met-Leu-Phe), the PMNL required conditioning of the cells at 22 degrees C or higher temperature prior to stimulus addition. This was not required when phorbolmyristate acetate or opsonized yeast particles were used as stimulus. When cell samples were obtained from PMNL suspensions during 240 min from preparation, the chemiluminescence signal triggered by f-Met-Leu-Phe progressively increased. Scatchard plot analysis of the chemiluminescence data indicated that storage of the cells resulted in modulation of both the number of functional receptors and the affinity for the receptor. The importance of receptor function control in the inflammatory process is discussed.

Mechanism of the serum defect in yeast opsonization in children with fulminant hepatic failure (FHF)

Defective opsonization of heat-killed baker's yeast was found in all 14 children with fulminant hepatic failure (FHF) but returned to normal in two who recovered and was normal in six mothers of patients. Yeast opsonization was significantly correlated with factor B activity of FHF serum but not with other components of classical or alternative pathways of complement. Reconstitution and family studies suggested that defective yeast opsonization in FHF is secondary and, although dependent on factor B activity, is qualitatively and quantitatively similar to that of primary yeast opsonization deficiency. These findings suggest that the factors responsible for opsonization of yeasts, or their regulation, are synthesized or controlled by the liver.

A study of C3b deposition on yeast surfaces by sera of known opsonic potential

C3c fragments released by the actin of trypsin from C3b molecules bound to zymosan may be readily quantitated by conventional gel techniques to give a measurement of the efficiency of C3b opsonization. Using this approach, the rate of deposition of C3b molecules was found to be very rapid in sera known to opsonize yeast normally. In contrast, sera defective in yeast opsonization deposited C3b much more slowly. The C3b elution technique was found to correlate well with both a direct phagocytosis assay using baker's yeast (r = 0.87, P less than 0.001) and a recently described neutrophil iodide uptake assay (r = 0.88, P less than 0.001).

Inhibition of the in vitro growth of Plasmodium falciparum by human polymorphonuclear neutrophil leucocytes

Polymorphonuclear neutrophil leucocytes (PMN) from children with acute Plasmodium falciparum malaria significantly inhibited parasite growth in homologous and in non-immune sera. Phagocytosis of schizonts in vitro was observed. PMN from uninfected children and uninfected adults had no effect on parasite growth.

Radioimmunoassay for yeast killer toxin from Saccharomyces cerevisiae

A radioimmunoassay was developed for the K1 killer toxin from strain T158C/S14a of Saccharomyces cerevisiae. 125I-labeled toxin was made to a specific activity of 100 microCi/mg of protein (1 microCi = 37 kBq). Antibody to purified toxin was prepared in rabbits using toxin cross-linked to itself. These antibodies, partially purified by 50% ammonium sulfate precipitation and Sepharose CL-6B column chromatography, produced one precipitation band with killer toxin and bound 125I-labeled toxin in a radioimmunoassay. The antibody preparation also bound with the toxins from another K1 killer, A364A, and three chromosomal superkiller mutants derived from it.

Immunological comparison of ribosomal proteins from archaebacteria

Antisera were raised in rabbits against ribosomal proteins of Methanobacterium bryantii and used to analyze immunological relationships to ribosomes from other archaebacteria, from eubacteria, and from yeasts. Cross-reaction could be detected within the methanogens and with a member of the extreme halophiles; the degree of immunological similarity reflected the relationship delineated by 16S ribosomal ribonucleic acid oligonucleotide analysis (Fox et al., Science 209:457-463, 1980). With the methods and the anti-total-protein sera employed, there was no detectable cross-reaction with ribosomal proteins or ribosomes from Sulfolobus sp., eubacteria, or yeast.

Effect of antimicrobial agents on human polymorphonuclear leukocyte microbicidal function

The effect of 19 antimicrobial agents on human polymorphonuclear leukocyte function was evaluated by chemiluminescence assays, yeast phagocytosis and killing, and lactate dehydrogenase release. Tetracycline and trimethoprim inhibited chemiluminescence and reduced killing at therapeutic concentrations of 2 microgram/ml. Cephalothin inhibited yeast killing at a concentration of 20 microgram/ml, but a significant depression of polymorphonuclear leukocyte chemiluminescence was encountered only at higher levels of 200 microgram/ml. The inhibition shown by these drugs was reversible. None of the other antimicrobial agents tested demonstrated inhibition of chemiluminescence, phagocytosis, or killing at usual clinical serum levels. No antimicrobial agent tested caused release of lactate dehydrogenase from polymorphonuclear leukocytes. The results suggest that therapeutic concentrations of tetracycline, trimethoprim, and cephalothin may inhibit optimal polymorphonuclear leukocyte microbicidal function.

Evidence for defect of complement-mediated phagocytosis by monocytes from patients with rheumatoid arthritis and cutaneous vasculitis

In-vitro measurements of the rate of monocyte phagocytosis of heat-killed yeast preopsonised in human AB serum from 14 patients with rheumatoid arthritis and 14 normal controls showed a significant reduction in five patients with active vasculitis but no change in nine with active arthritis alone. Further studies of complement- and Fc-mediated monocyte phagocytosis in which the rate constants (Kc and KFc respectively) were determined using complement-coated Saccharomyces cerevisiae and Candida albicans opsonised with IgG in monocytes from nine patients with rheumatoid vasculitis and 12 controls showed a significant reduction in Kc (p less than 0.01) but normal KFc. Kc was normal in three patients with inactive vasculitis. Low Kc was correlated with low serum C3 concentrations but not with Clq binding or anticomplementary activity, and no evidence of intracytoplasmic or membrane-bound immune complexes was detected in monocytes from patients with active vasculitis. These results show that cutaneous vasculitis in rheumatoid arthritis is associated with selective impairment of complement-mediated monocyte phagocytosis, which does not appear to result from receptor blockade by immune complexes.

Serological cross-reactivity between Sporothrix schenckii and various unrelated fungi

The serological cross-reactivity of Sporothrix schenckii with various unrelated fungi was investigated by use of immunodiffusion tests. A rabbit anti S. schenckii serum was obtained, which reacted with Cladosporium werneckii, C. carrionii, C. bantianum, Coccidioides immitis, Phialophora jeanselmei, P. gougerotii, P. dermatitidis, Fonsecaea pedrosoi, Aspergillus fumigatus, Histoplasma capsulatum and Trichophyton mentagrophytes, but not with Saccharomyces cerevisiae antigens. The serological determinants responsible for the cross-reactions were suggested to be D-galactosyl residues.

Macrophage antimicrobial activity: evidence for participation by lysosomes in the killing of Saccharomyces cerevisiae by normal resident macrophages

Ammonium chloride added to normal resident mouse peritoneal macrophages reduced the rate of killing of ingested Saccharomyces cerevisiae. It is suggested that this is attributable to the inhibition by ammonia of phagosome-lysosome fusion or of lysosomal protein degradation and that, consequently, lysosomal mechanisms contribute to the normal killing of these yeasts.

Polymorphonuclear neutrophil iodination response as an estimate of defective yeast opsonization

Polymorphonuclear neutrophil iodide uptake can be used as a measure of yeast opsonization and optimal assay conditions are described for the identification of sera defective in this function. The use of standard normal and defective sera permits correction of inter-assay variations resulting from the use of different cell donors. The iodination assay correlated well (r = 0.74, P less than 0.001) with a direct assay of yeast opsonization when both were used to measure this function in a panel of 72 sera. Differences in results between the two assay systems for some sera may be explained by a requirement for two different surface-associated opsonic molecules in the initiation of neutrophil metabolic activity.

Immunochemical analysis of the plasma membrane from baker's yeast Saccharomyces cerevisiae

Yeast plasma membranes have been isolated from homogenized yeast cells, identified as pure plasma membrane vesicles which were used as antigens. By crossed immunoelectrophoresis with anti-membrane immunoglobulins, 17 discrete antigens have been detected in Triton X-100 extracts from plasma membranes. Three different immunoabsorption experiments were performed with : a) isolated membranes exposing the cytoplasmic surfaces (PS) and the external surfaces (ES), b) yeast protoplasts exposing only antigenic determinants on the ES, c) lysed protoplasts which had been saturated on the ES with antibodies prior to lysis. These absorption experiments demonstrated that seven of the antigens are expressed on the ES while eight immunogens expose antigenic determinants on the PS. Four of the principal immunoprecipitates are not affected by absorption with surface antigens whereas two of the antigens indicate transmembrane characteristics. Of these 17 immunoprecipitates four were shown by zymograms to possess enzymatic activities: ATPase (EC 3.6.1.3) and NADH-dehydrogenase (EC 1.8.99.3) (three separate components). Three of these enzymes are expressed on the PS, and one NADH-dehydrogenase exposes determinants on the ES of the protoplasts. The presence of antigens on the PS of the plasma membrane could also be demonstrated on micrographs by the indirect ferritin-antibody labeling technique followed by freeze-etching and shadowing of the membranes.

Immunochemical studies of the mannans of Saccharomyces cerevisiae X2180-1A-5 and Saccharomyces cerevisiae 4484-24D-1 mutant strains, with special reference to their phosphate content

The mannans from Saccharomyces cerevisiae mutant strains X2180-1A-5 and 4484-24D-1, both of which were shown to contain small amounts of phosphate (less than 0.2%), were fractionated on a column of diethylaminoethyl-Sephadex into five subfractions designated as fractions I to V. These subfractions contain different amounts of phosphate, ranging from 0.03 to 0.09 (strain X2180-1A-5) and from 0.01 to 0.17% (strain 4484-24D-1). Fractions I to IV from strain X2180-1A-5 showed nearly identical precipitin activities against the homologous anti-whole cell serum, whereas fraction V, containing the largest amount of phosphate and protein among this mannan subfraction series, showed unexpectedly weaker precipitin activity than those of the other fractions. A synthetic mannan consisting or consecutive alpha-1 leads to 6-linked D-mannopyranosyl residues was found to be cross-reactive with all the mannan subfractions of strain X2180-1A-5 against anti-X2180-1A-5 serum. On the other hand, antibody-precipitating activities of the mannan subfractions of the latter strain were proportional to their phosphate content, although the increments of precipitated antibody nitrogen among the subfractions were quite small. However, fraction V of this mannan subfraction series, containing the largest amounts of phosphate and protein, showed lower precipitin activity than did the other four fractions. These findings indicate that mannans containing no phosphate or relatively small amounts of phosphate, such as those investigated in the present study, are less heterogeneous in the densities of the branching moieties than are highly phosphorylated mannans. These findings suggest that the transfer step of mannosyl-1-phosphate into the precursor(s) of the wild-type strain mannans during the biosynthetic process corresponds to the key reaction responsible for the anionic heterogeneity due to the density heterogeneity of the antigenic determinants.

Defective opsonisation and complement deficiency in serum from patients with fulminant hepatic failure

Serum from 23 of 26 patients with fulminant hepatic failure and grade IV encephalopathy had defective opsonisation of E. coli and yeast (S. cerevisiae). No toxic serum factors acting on the polymorphonuclear leucocytes or inactivators of the normal serum opsonisation factors were found. Complement deficiency was shown to be the most likely cause of the defect in opsonisation. The addition of a heat-labile fraction of normal serum at low concentration corrected the defect and factors of both the classical and the alternative pathways of complement were reduced to below 40% of the activity of the control serum. During the early stages of clinical recovery serum opsonisation and complement activity returned to normal with statistically significant correlations between tests of opsonisation and total haemolytic complement CH50, C3 and total alternative pathway activity. Defective serum opsonisation and complement deficiency represent major defects in the body's defences against infection.

Defective yeast opsonisation of serum in tuberculosis

We have studied the opsonising ability of the sera of 92 patients with tuberculosis. Fourteen per cent of these patients showed defective opsonising ability compared with 4% in a clinic control group. This increased frequency in TB was accounted for by the greatly increased proportion with defects found in patients with intrathoracic TB (21%). We may have identified a section of the population with a specific genetically linked abnormality of a host defence mechanism which renders them more susceptible to intrathoracic TB. Further population studies are required.

Yeast opsonisation in children with chronic diarrhoeal states

Four patients with defective yeast opsonisation and protracted diarrhoea are reported. Plasma infusions improved the opsonising function in all 4 and the diarrhoea in 3. This immunological abnormality was assessed in 100 sequential patients with chronic diarrhoea associated with various gastrointestinal disorders; 52 with protracted diarrhoea and failure to thrive of undetermined cause, 26 with 'toddler diarrhoea', 8 with coeliac disease, 5 with chronic inflammatory bowel disease, and 9 with miscellaneous disorders. 23% of the patients with protracted diarrhoea of undetermined cause had defective opsonisation, a greater proportion (P less than 0.05) than that in 'toddler diarrhoea' or the remaining patients, in whom the frequency (4%) was similar to that (5%) in healthy populations. We suggest that yeast opsonisation be tested in children with protracted diarrhoea, as plasma infusions can be an effective form of treatment.

Altered immunochemical reactivity of Saccharomyces cerevisiae a-cells after alpha-factor-induced morphogenesis

Antibodies were raised against Saccharomyces cerevisiae a-cells that had been exposed to the sex pheromone, alpha-factor. After adsorption of the antiserum with diploid cells, antibodies remained that reacted specifically with the mannan from haploid cells. The characteristic determinant was observed in mannan from pheromone-treated a-cells, in mannan from untreated alpha-cells, and at a much lower concentration, in mannan from control a-cells. The antigens from these three mannans appeared to be identical. The determinant was destroyed by mild-acid hydrolysis or periodate oxidation, but not by proteolysis or digestion with exo-alpha-mannanase. Mutants with altered mannan were unable to express the antigen. Complete acid hydrolysates mannan from alpha-factor-treated a-cells contained mannose, glucose, and N-acetylglucosamine. Partial acid hydrolysis, under conditions that destroyed the antigenic determinant, released only mannose and mannobiose. The mannose fraction was labeled to high specific activity during response of a-cells to alpha-factor if radioactive glucose was the carbon source. Neither alpha- not beta-D-mannopyranosyl phosphate was a hapten. The results are consistent with the presence of a haploid-specific antigen containing an acid-labile mannose determinant and show that the amount of this antigen in a-cell mannan is increased in response to alpha-factor.

[Cross reactions of eight yeasts and their importance in serological Candida diagnostic (author's transl)]

While the antigen structure of yeast cell walls is well known, the immunological cross reactivity of these is often difficult to interpret. The cross reactions of eight yeasts were tested in rabbit hyperimmune sera by the indirect immunofluorescence test. Among the eight species examined were the medically important yeasts C. albicans, C. pseudotropicalis, C. krusei, C. parapsilosis, C. tropicalis, T. glabrata, and C. guilliermondii and the apathogenic yeast S. cerevisiae. It has been shown, that there is no correlation between the number of common antigens and the degree of cross reactivity which give identical titers. Therefore it appears, that the quantitative contributions of the single antigens have an important rule, i.e., some antigens are immunogenic in one species while having only hapten characteristics in another. Further the results show that in infections with C. krusei, C. pseudotropicalis, and C. guilliermondii homologous antigens have to be used for the serological diagnosis. The testing of human sera with the yeast antigens by the same methods showed that the strikingly distributions of the Candida titer and the Saccharomyces titer were similar. A larger number of sera of healthy people and patients were compared in the hemagglutination test. These results showed that pathological C. albicans titers cannot be caused by S, cerevisiae antibodies.

The synthesis of antigenic determinants for yeast D-mannans and a linear (1to 6)-alpha-D-gluco-D-mannan, and their protein conjugates

2-O-Benzoyl-3,4,6-tri-O-benzyl-1-O-tosyl-D-mannopyranose and 2,3,4-tri-O-benzyl-6-O-(N-phenylcarbamoyl)-1-O-tosyl-D-glucopyranose were allowed to react with partially blocked 2-[4-(ptoluensulfonamido)phenyl]ethyl alpha-D-manno- and gluco-pyranosides. Disaccharides having alpha-D-Manp-(1 to 2)-alpha-D-Manp, alpha-D-Manp-(1 to 6)-alpha-D-Glcp, alpha-D-Manp-(1 to 6)-alpha-D-Manp, and alpha-D-Glcp-(1 to 6)-alpha-D-Manp structures, and a branched trisaccharide having the structure alpha-D-Manp-(1 to 2)-[alpha-D-Manp-(1 to 6)]-alpha-D-Manp were synthesized. The oligosaccharid:s were deblocked with sodium in liquid ammonia to give glycopyranosides having a free primary aromatic amine which were converted into isothiocyanate derivatives with thio-phosgene. The functionalized oligosaccharides were then coupled to bovine serum albumin to give protein conjugates.