Skin prick test reactions to brewer's yeast (Saccharomyces cerevisiae) in adult atopic dermatitis patients

The sensitizing capacity of brewer's yeast (Saccharomyces cerevisiae) was studied with the skin prick test method in 449 subjects, including 226 atopic dermatitis (AD) patients, 50 patients with allergic rhinitis (AR) and/or asthma (A), and 173 nonatopic controls. A positive SPT reaction (> or = + +) was seen in 94% of patients with severe AD, in 76% with moderate AD, and in 25% with mild AD or no history of AD. Patients with AR and/or A and nonatopic controls displayed a positive reaction in only 8 and 2% of cases, respectively. There was also a parallel skin prick test reactivity with other yeasts including Pityrosporum ovale and Candida albicans, suggesting cross-reactivity. Parallel skin reactivity was observed also with molds and animal dander but not with pollen or house-dust mite. A significant correlation was also found between total serum IgE level and skin prick test (SPT) results with S. cerevisiae.

[Mechanisms of clearance of foreign bodies by macrophages]

Macrophages have specific functions related to the sites where they are found. Pulmonary alveolar macrophages (PAM) may play an important role the clearance of invading and degenerative substances from the alveolar spaces. To clarify the mechanisms of the clearance by macrophages, we studied the role of scavenger receptors (SR) and Fc receptors (FcR) of PAM. 1) SR: Expression and localization of SR in human PAM. Type I and II SRs were expressed in human PAM, and the two SRs were confirmed in the same cells by double staining method using polyclonal antibodies to the SRs. These SRs were localized on the cell membrane and the endosome in part. The expression of SR in PAM from normal nonsmokers, smokers and patients with pneumoconiosis was studied, but there were no differences among these groups. Kinetics of SR and acetylated low density lipoprotein (acLDL) in PAM. SR recognized acLDL, and SR and acLDL-Au conjugates were concentrated in a coated pit 2 min after incubation. The conjugates were then internalized in the endosome 5 min after incubation. A few acLDL-Au conjugates were present in the endosome near the nucleus, but most of them were found in the lysosome 10 min after incubation. SR was found in the Golgi apparatus 15 min after incubation. These results suggest that SR in PAM may play an important role in the removal of alveolar surfactant. 2) FcR: Effects of FcR mediated phagocytosis on O2-release and phagosome-lysosome fusion in the phagosome of PAM.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies directed against a yeast carboxyl-terminal peroxisomal targeting signal specifically recognize peroxisomal proteins from various yeasts

The carboxyl-terminal tripeptide Ala-Lys-Ile is essential for targeting Candida tropicalis trifunctional enzyme (hydratase-dehydrogenase-epimerase) to peroxisomes of both Candida albicans and Saccharomyces cerevisiae (Aitchison,J.D., Murray, W.W. and Rachubinski, R. A. (1991).J. Biol. Chem. 266, 23197-23203). We investigated the possibility that this tripeptide may act as a general peroxisomal targeting signal (PTS) for other proteins in the yeasts C. tropicalis, C. albicans, Yarrowia lipolytica and S. cerevisiae, and in rat liver. Anti-AKI antibodies raised against the carboxyl-terminal 12 amino acids of trifunctional enzyme were used to search for this PTS in proteins of these yeasts and of rat liver. The anti-AKI antibodies reacted exclusively with multiple peroxisomal proteins from the yeasts C. tropicalis, C. albicans and Y. lipolytica. There was a weak reaction of the antibodies with one peroxisomal protein from S. cerevisiae and no reaction with peroxisomal proteins from rat liver. Antibodies directed against a synthetic peptide containing a carboxyl-terminal Ser-Lys-Leu PTS (Gould, S. J., Krisans, S., Keller, G.-A. and Subramani, S. (1990). J. Cell Biol. 110,27-34) reacted with multiple peroxisomal proteins of rat liver and with peroxisomal proteins of yeast distinct from those identified with anti-AKI antibodies. These results provide evidence that several peroxisomal proteins of different yeasts contain a PTS antigenically similar to that of C. tropicalis trifunctional enzyme and that this signal is absent from peroxisomal proteins from at least one mammalian system, rat liver.

Cross-reaction of clinical isolates of bacteria and yeasts with the chlamydiazyme test for chlamydial antigen, before and after use of a blocking reagent

More than 1,000 clinical isolates of bacteria and yeasts were identified, subcultured, and tested at 10(8) colony-forming units per milliliter with the Chlamydiazyme assay to determine the variety of microorganisms which could cause false-positive results for Chlamydial antigen. False-positive Chlamydiazyme results were obtained from 27 of 465 (5.8%) gram-negative, aerobic, or facultatively anaerobic bacterial isolates (including 8 of 39 [20.5%] Neisseria gonorrhoeae and 8 of 149 [5.4%] Escherichia coli isolates) and also from 2 of 46 (4.3%) Bacteroides species isolates. No false-positive results were obtained either from 373 gram-positive bacterial isolates or from 153 yeasts. Results from 21 of 29 (72.4%) isolates that cross-reacted with Chlamydiazyme antibodies were repeatedly positive, but all 21 were confirmed as false-positive results using a blocking antibody. When an initial Chlamydiazyme result is positive, repeating the test, with and without use of the blocking antibody, appears to be effective in identifying those results (more likely from poorly collected endocervical specimens) that are falsely positive, even in the presence of high concentrations of cross-reacting bacteria. Microscopic determination of endocervical specimen adequacy also may help to minimize false-positive (and false-negative) Chlamydiazyme results.

Presence of the diurnal rhythms of monocyte count and macrophage activities in chicks

The diurnal rhythms of monocyte count in the peripheral blood and the nonspecific activities of peritoneal macrophages were investigated in 6- to 12-wk-old White Leghorn chicks. It was evident that monocyte count and activities of peritoneal macrophages, i.e., phagocytosis and microbicidal activity, showed clear diurnal rhythms. The rhythmic pattern of monocyte count was biphasic, unlike those of humans or mice (which exhibit a monophasic fluctuation pattern). Diurnal rhythms of phagocytic activity and microbicidal activity also showed two peaks. However, the correspondence of fluctuation patterns between phagocytic activity and microbicidal activity that have been shown in chicken heterophils was not shown in chicken macrophages. This result suggests that the activities of both functions fluctuate independently in chicken macrophages. The patterns of macrophage-nonspecific activities were not in agreement with any rhythmic patterns concerning B cell and T cell activities reported previously. This result may indicate that the accessory functions of macrophage for helper T cell activation are not involved in the formation of the rhythmic patterns of B cell and T cell functions in chicks.

Distribution and immunological characterization of microbial aldehyde reductases

The distribution of microbial aldo-keto reductases was examined and their immunochemical characterization was performed. p-Nitrobenzaldehyde, pyridine-3-aldehyde and ethyl 4-chloro-3-oxobutanoate reductase activities were found to be widely distributed in a variety of microorganisms. In immunodiffusion studies, most yeasts belonging to the genera Sporobolomyces, Sporidiobolus and Rhodotorula formed precipitin bands with anti-Sporobolomyces salmonicolor aldehyde reductase serum. Furthermore, the results of immunotitration experiments suggested that Sporobolomyces salmonicolor AKU 4429 contains other enzyme(s) which can reduce p-nitrobenzaldehyde, pyridine-3-aldehyde and/or ethyl 4-chloro-3-oxobutanoate, and which are inactivated by anti-Sporobolomyces salmonicolor aldehyde reductase serum.

Arachidonic acid is essential for IgG Fc receptor-mediated phagocytosis by human monocytes

Phagocytosis is a specialized function of neutrophils and macrophages that requires coordination of multiple biochemical and biophysical events. Considerable progress has been made in identifying the membrane receptors involved in phagocytosis, but the intracellular signaling pathways that are necessary for particle ingestion are poorly understood. In an effort to address this complex question, we investigated the role of arachidonic acid (AA) in the uptake of yeast and IgG-coated E (EIgG) or C-coated E. Human monocytes, labeled with 3H AA, released this label during phagocytosis of yeast and EIgG, but not in response to EC3b. The PL inhibitors bromophenacyl bromide and manoalide abolished the release of 3H and inhibited phagocytosis of EIgG in parallel. Both drugs caused a similar inhibition of yeast-mediated 3H release but had little effect on yeast ingestion. Similar results were obtained with the inhibitor quinacrine (mepacrine). Exogenously added AA and dihomo-gamma-linolenic acid restored bromophenacyl bromide-inhibited EIgG ingestion; arachidonate analogs eicosatrienoic acid and eicosapentanoic acid did not. Inhibition of the cyclooxygenase and lipoxygenase pathways for AA metabolism by indomethacin or BW755C did not affect EIgG phagocytosis, demonstrating that these major AA metabolic pathways are not involved in phagocytic signaling. These experiments suggest that release of AA is essential for EIgG ingestion and that phagocytosis in monocytes proceeds by at least two mechanisms, one dependent on AA (EIgG) and one independent of it (yeast).

The immunoadjuvant effect of soluble glucan derivatives in mice

We examined the effect of soluble derivatives of yeast glucan on the humoral immune response of various strains of inbred mice after administration of different doses according to various schedules. Glucan was injected i.v. or s.c. in a single dose or repeatedly. The immune response was examined by determining the titres of serum hemagglutinins against sheep erythrocytes (SRBC-Ab). The immunoadjuvant effect of glucan derivatives depends on the inbred strain used, on the dose of glucan, mode and time of administration with respect to antigen injection. The results have shown that the stimulatory effect of glucan derivatives occurred already after a single injection, the optimum dose being 10-20 mg/kg. Intravenous injection was more efficient than the subcutaneous one. In some cases, a slight increase of the spleen mass was observed.

Immunogenicity of yeast-derived hepatitis B vaccine in Pakistani adults

A study of the immunogenicity and safety of 20 micrograms recombinant DNA yeast derived hepatitis B vaccine was conducted in 153 Pakistani adults. All participants were in good physical condition, had negative hepatitis B serological markers (HBsAg, anti-HBs, anti-HBc) and normal ALT. Anti-HBs developed in 33%, 81% and 98% of subjects one month after the first, second and third dose respectively. Minor systemic and local side-effects were observed in 39% of individuals. We conclude that yeast derived hepatitis B vaccine is safe, effective and immunogenic in Pakistani adults.

Production and isolation of rabbit anti-idiotypic antibodies directed against the human monocyte receptor for yeast beta-glucans

beta-Glucan receptors are present on mammalian phagocytic cells and provide an important physiologic mechanism for opsonin-independent clearance of yeasts and fungi. To prepare an immunologic probe to human monocyte beta-glucan receptors, an approach was taken that focused on the ligand specificity of the receptors as expressed by an anti-Id. The algal beta-glucan laminarin was chemically coupled to protein carriers to prepare an immunogenic beta-glucan. Three mouse IgG2a mAb were raised against laminarin, and one, mAb OEA10, exhibited specificity for the soluble unit ligand yeast heptaglucoside and the ligands present on zymosan and glucan particles that are recognized by monocyte beta-glucan receptors. These findings prompted usage of mAb OEA10 as immunogen for the preparation of an anti-Id. The resulting rabbit antiserum was subjected to sequential immunoaffinity chromatography to purify anti-idiotypic antibodies. The final product contained only IgG by SDS-PAGE and was shown to be specific by its selectively blocking binding of 125I-mAb OEA10 to laminarin. Pretreatment of adherent monocytes with 0.4 micrograms/ml of the anti-Id reduced the numbers of monocytes ingesting zymosan and glucan particles by 64 and 43%, respectively, whereas ingestion of IgG-coated SRBC was unaffected by as much as 16 micrograms/ml of the anti-Id. Incubation of adherent monocytes with increasing amounts of 125I-anti-Id in the absence and presence of 40-fold molar excess unlabeled anti-Id revealed dose-dependent specific binding, which approached plateau levels with 1 microgram/ml of labeled anti-Id. Thus, the anti-Id binds to monocytes and displays functional characteristics of soluble beta-glucan ligands, indicating that some of the anti-idiotypic antibodies recognize epitopes within monocyte beta-glucan receptors.

Schistosoma mansoni modulation of phagocytosis in Biomphalaria glabrata

Both short-term (3 hr) exposure of Biomphalaria glabrata snails (M-line and 13-16-R1) to Schistosoma mansoni (PR1) miracidia and in vitro incubation of parasite sporocysts with host hemolymph components altered host phagocytic ability. Hemocytes obtained from susceptible (M-line) snails that had been exposed to parasite miracidia for 3 hr showed reduced levels of phagocytosis of yeast cells in vitro compared to hemocytes from unexposed individuals. Incubation of whole hemolymph with sporocysts in vitro also reduced yeast phagocytosis in this susceptible strain. In contrast, resistant (13-16-R1) hemocytes showed increased levels of yeast phagocytosis after in vitro incubation with the parasite, and the opsonic properties of 13-16-R1 plasma were greater after exposure of snails to miracidia. These strain-specific effects of S. mansoni on host hemocyte phagocytosis and plasma opsonization were seen only when both plasma and hemocytes were present at the time of exposure to the parasite.

High levels of circulating neutralizing antibody in normal animals to recombinant mouse interferon-beta produced in yeast

Plasma from normal outbred Swiss mice not previously given interferon (IFN) neutralized a glycosylated (high-mannose) recombinant murine IFN-beta made in yeast (rMuIFN-beta y). The neutralization antibody titers were as high as 1:6,000 versus rMuIFN-beta y, whereas the titers obtained with native murine IFN-beta (MuIFN-beta) were 100-fold less; a recombinant murine IFN-beta make in Escherichia coli (rMuIFN-beta ec) was not neutralized at 1:10 dilution of plasma. An ELISA using rMuIFN-beta y demonstrated that it is gamma immunoglobulins in normal mouse plasma that bind rMuIFN-beta y. Normal rabbit serum also had very high endogenous neutralizing activity (1:5,300) against rMuIFN-beta y. Significant neutralizing activity also was detected in newborn bovine and normal human serum as well as pooled human immune serum globulin. Thus, endogenous neutralizing activity directed presumably at the carbohydrate residues of highly glycosylated recombinant proteins produced in yeast may limit their clinical utility.

Molecular cloning of a gene encoding a Chlamydia psittaci 57-kDa protein that shares antigenic determinants with ca. 60-kDa proteins present in many gram-negative bacteria

In order to develop reagents to study the immune response of guinea pigs to infection by Chlamydia psittaci guinea pig inclusion conjunctivitis strain (GPIC), we constructed a plasmid clone bank with C. psittaci DNA. One of the recombinant clones isolated produced large amounts of a 57-kilodalton (kDa) protein that was immunoreactive with sera from GPIC infected guinea pigs. While investigating this recombinant protein, we discovered that all the Gram-negative bacteria analyzed so far have immunoreactive proteins of similar size. This protein seems to be a 'common antigen' already described in various Gram-negative bacteria.

Recombinant-yeast-derived hepatitis B vaccine in healthy adults: safety and two-year immunogenicity of early investigative lots of vaccine

We tested the safety and long-term immunogenicity of two of the early investigative lots of a recombinant-yeast-derived hepatitis B vaccine in immunocompetent adults. Three 10-micrograms doses of recombinant hepatitis B vaccine (Merck Sharp & Dohme Research Laboratories, West Point, PA) were administered by deltoid intramuscular injection at time 0, 1, and 6 months to 65 seronegative adult health workers. Following a complete three-injection course, 98% of vaccinees acquired anti-HBs, 97% at levels greater than 10 mlU/ml, and 95% maintained such "protective" antibody levels at 1 year. At 2 years, 93% retained antibody, but only 68% had levels greater than 10 mlU/ml. In those who responded to vaccination by achieving any detectable level of antibody, the peak geometric mean titer of anti-HBs, measured at 9 months, was 741 +/- 6 mlU/ml; the geometric mean titer fell to 348 +/- 6 at 1 year and to 66 +/- 7 at 2 years. Side effects were trivial, and levels of yeast antibody, as measured by radioimmunoassay, were not changed from prevaccine levels. No serious adverse effects were encountered, and neither type B nor non-B hepatitis occurred in any vaccine. These findings demonstrate that the recombinant yeast hepatitis B vaccine is safe and immunogenic but that 10 micrograms of the early investigative lots of the recombinant vaccine is less immunogenic than 20 micrograms of the plasma-derived vaccine. Recipients of early investigative vaccine lots should be considered for booster vaccination with currently available, more immunogenic vaccine lots.

[Specific prevention of disorders in the immune status of experimental animals by inhalation exposure to products of microbiological synthesis]

The possibility of the specific prophylaxis of the immunosuppressing effect of the products of microbiological synthesis (MBS) on laboratory animals by the preliminary immunization of the animals with the vaccine prepared from the live culture of fungi releasing MBS products has been shown.

Ligand-specific cross-inhibition of monocyte phagocytosis

Human monocytes exposed to particles reacting with receptors of one specific type demonstrate a markedly reduced phagocytosis of particles reacting with receptors of another type. The phagocytosis of yeast particles (Saccharomyces cerevisiae) coated with C3 fragments and of uncoated ones by monocytes can inhibit the subsequent endocytosis of sheep erythrocytes sensitized with IgG antibody and vice versa. The erythrocytes were labelled with 51Cr and the yeast particles with 125I. The dependence of the receptor-ligand reaction on temperature and time of preincubation, as well as on ratio of cell and particle, suggests that this cross-inhibition may be associated with plasma membrane modulations beginning with the attachment of ligands to a receptor and followed by their endocytosis. The differences between the functions of temperature, time, and concentration in inhibition caused by different receptor-ligand reactions suggest that these membrane modulations are probably ligand-specific processes.

RNA11 protein is associated with the yeast spliceosome and is localized in the periphery of the cell nucleus

The yeast rna mutations (rna2 through rna10/11) are a set of temperature-sensitive mutations that result in the accumulation of pre-mRNAs at the nonpermissive temperature. Most of the yeast RNA gene products are involved in and essential for mRNA splicing in vitro, suggesting that they code for components of the splicing machinery. We tested this proposal by using an in vitro-synthesized RNA11 protein to complement the temperature-sensitive defect of the rna11 extract. During the in vitro complementation, the input RNA11 protein was associated with the 40S spliceosome and a 30S complex, suggesting that the RNA11 protein is indeed a component of the spliceosome. The formation of the RNA11-associated 30S complex did not require any exogenous RNA substrate, suggesting that this 30S particle is likely to be a preassembled complex involved in splicing. The RNA11-specific antibody inhibited the mRNA splicing in vitro, confirming the essential role of the RNA11 protein in mRNA splicing. Finally, using the anti-RNA11 antibody, we localized the RNA11 protein to the periphery of the yeast nucleus.

Allergenic cross-reactivity of yeasts

Yeast allergen extracts of Candida albicans, C. pseudotropicalis, C. krusei, C. parapsilosis, C. tropicalis, C. guilliermondi, C. humicola, C. norwegica, C. utilis, Cryptococcus albidus, Geotrichum candidum, Pityrosporon pachydermatis, P. ovale, Rhodotorula minuta, R. rubra, Saccharomyces cerevisiae, Torulopsis glabrata and Trichosporon cutaneum were investigated regarding their common allergenic properties. The enzyme immunoassay (EIA) using rabbit anti-Candida albicans antiserum showed remarkable immunological cross-reactivity only between the Candida species. However, there was a significant multiple sensitivity to the extracts of C. albicans, C. utilis, Cr. albidus, R. rubra and S. cerevisiae in skin prick testing in atopic patients, suggesting the possible presence of one or more common skin reactive allergens.

Therapeutic concentrations of melphalan do not affect yeast cell phagocytosis by monocytes

The effect of melphalan on monocyte phagocytosis was assessed by studying the uptake of fluorescent yeast cells by glass-adherent monocytes (a fluorescence-quenching technique). In contrast to several other cytotoxic agents, melphalan did not inhibit monocyte phagocytosis. Although the main immunosuppressive side effect of most cytotoxic drugs appears to be due to bone marrow depression with reduction of leukocyte counts, it is reasonable to assume that lack of interference with the function of mature leukocytes is a favourable feature of an antineoplastic drug.

[Determination of specific IgE against 16 widespread mould genera. Improvement of the efficacy of the diagnosis of allergy to moulds]

Serum samples from 55 Scandinavian and US patients with a clinical history of mould allergy were screened for specific IgE Ab against 16 different moulds, the 6 mould in the Phadebas RAST panel and 10 new moulds. The studies were performed using RAST-based techniques and the nitrocellulose immunoblotting method. The RAST screening of the patient panel, revealed that 42 patients (76%) had specific IgE to at least one of the 16 moulds. The two most frequent moulds were Rhizopus and Botrytis positive in 29 patients (53%) and 27 patients (42%), respectively. Top three in terms of frequency in the US patient group were: Rhizopus greater than Botrytis greater than Phoma and in the Scandinavian group: Cladosporium greater than Botrytis greater than Helminthosporium. 15 patients (27%) were negative against the moulds in the Phadebas RAST panel, but had specific IgE against one or more of the 10 new moulds. IgE Ab concentrations measured with different genera showed different degrees of positive concordance, e.g. Botrytis-Helminthosporium (79%) and Alternaria-Rhizopus (38%), indicating complex patterns of crossreacting and genus specific allergens. This was confirmed by immunoblotting with 22 (greater than 1 PRU/ml) of the 55 sera showing up to 25 IgE binding components. The results strongly suggest that the importance of some mould genera has been underestimated as allergens.

Phagocytosis of yeast cells by monocytes: effects of fluorouracil, doxorubicin and mitomycin

The drugs in the FAM combination (fluorouracil, doxorubicin, mitomycin) were tested for a possible effect on monocyte function by means of a glass-surface fluorescence-quenching technique of monocyte phagocytosis. The individual drugs significantly inhibited monocyte phagocytosis. The inhibition was located at the engulfment phase of phagocytosis and in an order of magnitude of 20-30%. The FAM combination did not suppress monocyte phagocytosis more than each one of the individual drugs. It is suggested that a slight inhibition of monocyte phagocytosis is a cost of cytotoxic treatment.

Aromatic alpha-glycosides of mannose are powerful inhibitors of the adherence of type 1 fimbriated Escherichia coli to yeast and intestinal epithelial cells

Adherence of bacteria via their surface lectins to host epithelial cells is considered an important initial event in bacterial pathogenesis. Mannose-specific (type 1) fimbriae are among the most commonly found lectins in enterobacteria. We studied the effect of aromatic alpha-glycosides of mannose on the agglutination of mannan-containing yeasts by different strains of Escherichia coli and on the adherence of the bacteria to guinea pig ileal epithelial cells. In both systems these compounds were considerably more effective inhibitors than methyl alpha-mannoside, with 4-methylumbelliferyl alpha-mannoside and p-nitro-o-chlorophenyl alpha-mannoside being the strongest inhibitors. Both compounds were approximately 400-times stronger inhibitors of yeast agglutination by E. coli O128 than was methyl alpha-mannoside and 1,000- and 470-fold stronger, respectively, than was methyl alpha-mannoside in inhibiting the adherence of the bacteria to ileal epithelial cells. 4-Methylumbelliferyl alpha-mannoside was 540 to 1,000 times more effective in inhibiting yeast agglutination by four additional strains of mannose-specific E. coli. It was also more efficient than methyl alpha-mannoside in removing adherent E. coli O128 from ileal epithelial cells. Our results provide further evidence that type 1 fimbriae of E. coli possess a hydrophobic region next to the mannose-binding site. The results suggest that 4-methylumbelliferyl alpha-mannoside and p-nitro-o-chlorophenyl alpha-mannoside are good candidates for the design of therapeutic agents that may prevent adherence in vivo and infection by E. coli strains that express type 1 fimbriae.

A human auto-immune antibody specifically recognizing initiator methionine tRNA from yeast and higher eucaryotes

Analysis of sera from 168 patients with autoimmune disorders revealed that one patient with Sjôgren's syndrome produced antibodies against deproteinized initiator methionine tRNA in addition to those against La protein. This anti-tRNAimet recognizes also tRNAimet from yeast but not from Phaseolus vulgaris chloroplasts (bean) or E. coli. It appears therefore that the epitope could be located in the TF loop in which an A residue in position 60 and the AUCG sequence are the only common features in yeast and human tRNAimet.