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31.
A hemocyte surface membrane marker (BGH1) has been identified using hemocyte-specific monoclonal antibodies (mABs) generated by somatic cell fusion methods. The BGH1 epitope was expressed on a subpopulation of circulating, glass-adherent blood cells from two strains of the snail, Biomphalaria glabrata. Approximately 40% of the circulating hemocytes from the PR albino (M-line) B. glabrata strain were BGH1?, compared to a prevalence of 10% BGH1+ cells in the 10-R2 snail strain. When hemocytes were firmly attached and spread on a glass surface, BGH1+ cells were morphologically distinguishable from BGH1? cells by their ovoid shape and the presence of short, thin filopodial projections along the ectoplasmic border. In contrast, BGH1? hemocytes were more pleomorphic and possessed long, spike-like filopodia. Moreover, the BGH1 epitope was trypsin-resistant and retained its antigenic reactivity with probe mABs following fixation with paraformaldehyde or paraformaldehyde/MeOH. Fixation with glutaraldehyde, however, significantly reduced mAB binding to the BGH1 surface epitope. There was no apparent age-dependent expression of the BGH1 determinant since circulating hemocyte populations in very young (1–2 mm) to adult (10–12 mm) snails were composed of both BGH1+ and BGH1? subpopulations. Quantitative shifts in the prevalence of epitope-bearing hemocytes between the smallest snail size class (1–2 mm) and the larger snails (3–4 and 10–12 mm) are believed to be due to a differential production and/or release of BGH1? hemocytes within the blood circulation rather than a gradual age-related change in the expression of surface antigens on individual cells. Experiments designed to assess the in vitro phagocytic capability and lysosomal acid phosphatase (APase) activity of mAB-reactive hemocytes revealed that BGH1+ cells, when compared to those lacking the surface marker, were significantly reduced in both their phagocytic and APase-producing activities. Since the PR albino strain of B. glabrata possesses a higher proportion of BGH1? hemocytes and a lower total concentration of circulating cells than do snails of the 10-R2 strain, PR albino snails are thus potentially reduced in their natural capacity to mount cellular reactions against foreign materials. 相似文献
32.
James W. Freeman Amitava Chatterjee Brenda E. Ross Harris Busch 《Molecular and cellular biochemistry》1985,68(1):87-96
Summary Extractable nucleolar proteins from HeLa cells were used as a source of antigen to immunize mice for monoclonal antibody (MAb) production. Ten of the resulting MAbs shown to identify nucleolar phosphoprotein (110 kD/pI 5.5) were purified and used in immunochemical studies to further characterize protein C23. All ten MAbs showed nucleolar localization by indirect immunofluorescence; one antibody (FR2) also showed some nucleoplasmic localization that was attributed to a shared epitope between protein C23 and a 72 kD nuclear/nucleolar antigen. Reciprocal antibody cross blocking studies indicated that the ten MAbs identified nine distinct epitopes on protein C23. Interestingly, seven of the nine epitopes were shown by immunofluorescence and competitive ELISA studies to be species related. Immunostained patterns of exponentially growing HeLa cells suggest that protein C23 exists in vivo solely as a 110 kD peptide. However, protein C23 was subject to rapid degradation into a number of proteolytic fragments upon extraction or storage of isolated nucleoli. The failure to find protein C23 related peptides with molecular sizes less than 110 kD in exponentially growing cells and the lack of cytoplasmic localization of any of the ten MAbs suggests that protein C23 is not a prepro-protein processed in vivo to form ribosomal proteins as previously suggested (1). 相似文献
33.
Histoplasma capsulatum yeast cells have been studied by immunoelectron microscopy using rabbit polyclonal antisera and a biotin-avidin-peroxidase detection system. An antigenic surface layer has been visualized in the cell wall of immunostained organisms. This layer was not seen in samples prepared by standard electron microscopic methods or in negative controls used with the immunocytochemical technique. Without immunostaining the cell wall ofHistoplasma appeared almost transparent. In contrast, after immunoperoxidase staining the cell wall was conspicuous, bounded by the darkly stained outer layer. This electron dense layer, appeared to be a reservoir of surface antigens that were recognized by anti-Histoplasma antibodies.Abbreviations CHHA
Cystine-heart-hemoglobin agar
- PBS
phosphate buffered saline
- Ig
immunoglobulin
- TBS
Tris buffered saline
- DAB
3,3-diaminobenzidine tetrachloride
- FITC
fluorescein isothiocyanate
- M199
tissue culture medium 199, according to Morgan et al. (1950) 相似文献
34.
Peter H. Seidl Jochen R. Golecki Norbert Franken Karl Heinz Schleifer 《Archives of microbiology》1985,142(2):121-127
The peptide subunit pentapeptide H-L-Ala-D-Glu(L-Lys-D-Ala-D-Ala-OH)-NH2 of peptidoglycan was localized in the cell walls of several Gram-positive bacteria employing the indirect immunoferritin technique. Specific antibodies to the D-alanyl-D-alanine moiety of non-crosslinked peptide subunit pentapeptide were raised in rabbits by immunization with synthetic immunogen albumin-(CH2CO-Gly-L-Ala-L-Ala-D-Ala-D-Ala-OH)39. Specificity of these antibodies for the peptide subunit pentapeptide and not for the peptide subunit tetrapeptide was corroborated in a Farr-type radio-active hapten binding assay. Specificity of labelling with ferritin was established by immunoelectron microscopic controls, and by the excellent correlation between specific labelling of cells with ferritin and the particular peptidoglycan primary structure of bacterial strains investigated. Cells of Lactobacillus gasseri, Streptococcus pyogenes and Staphylococcus aureus revealing non-crosslinked peptide subunit pentapeptides in their peptidoglycans could specifically be labelled. Lactobacillus acidophilus and Bacillus subtilis, on the contrary, missing such pentapeptides, failed in labelling.The implication of this method to possibly localize the points of attack of penicillin or cycloserine is discussed.Abbreviations used meso-A2pm
meso-diaminopimelic acid
- DSM
Deutsche Sammlung für Mikroorganismen, Göttingen, FRG
This paper is dedicated to Professor Gerhart Drews on the occasion of his 60th birthday 相似文献
35.
ABSTRACT. The detailed behavioural mechanisms underlying an instance of compensation for changes in dietary nutrients are described for the first time in an insect. Nymphs of Locusta migratoria L. were given one of four artificial diets on the third day of the fifth instar, and their feeding patterns recorded in detail for 12 h. The diets represented combinations of two protein and two digestible carbohydrate levels (28% and 14% dry weight) presented in an otherwise complete nutrient mix. At the nutrient levels used, locusts regulated their intake of food with respect to protein but not digestible carbohydrate in the diet. They ate more of the lower protein diets by eating the same sized meals more frequently than insects fed on the higher protein diets. Compensation was not complete over the 12 h observation period: insects on the lower-protein diets ingested and absorbed 72% as much nitrogen as those insects fed on the higher-protein diets. Possible physiological mechanisms underlying the behavioural mechanisms are discussed. 相似文献
36.
Antisera have been developed against the wholecell antigens of Desulfovibrio africanus Benghazi and Walvis Bay, D. vulgaris Hildenborough, D. salexigens British Guiana, D. gigas, and D. desulfuricans Essex 6. An enzymelinked immunoadsorption assay (ELISA) was developed to measure the reaction of these antisera with the homologous and heterologous antigens. The ELISA method demonstrated a reaction between pre-immune sera and cells of D. africanus, D. gigas and D. desulfuricans, suggesting the presence of a lectin-like substance on these cell surfaces. Extensive cross-reactions were seen between the antisera and heterologous cells, suggesting the sharing of a number of surface antigens amongst the Desulfovibrio. However, the pattern of these cross-reactions was different from that observed for an ELISA reaction developed for the cytochrome c3 from various Desulfovibrio.Abbreviation ELISA
enzyme-linked immunoadsorption assay 相似文献
37.
Antisperm antibodies are implicated as one causative factor of infertility, but the target antigens have not been identified. Immune responses to sperm antigens are qualitatively variable even within a single mouse strain. We took advantage of this variability and immunized individual female mice to allogeneic sperm to reflect their natural exposure during mating. We determined the ability of the individual sera to inhibit in vitro fertilization and to bind to sperm antigens separated by electrophoresis. Compared to preimmune sera, four of five immune sera significantly inhibited in vitro fertilization. The serum from individual mice bound variable panels of sperm antigens. By comparing the panels, we identified two polypeptides with molecular weights of 40,000 and 44,000 that were bound by all sera. We propose that these molecules may be good candidates for further investigation of the immunoprophylaxis of pregnancy. 相似文献
38.
Epitope expression on primate lymphocyte surface antigens 总被引:1,自引:0,他引:1
The cross-reactivity of peripheral blood mononuclear cells from 28 nonhuman primates was investigated with ten kinds of Leu series of monoclonal antibodies specific to human T-, natural killer/killer-, and B-cells. The chimpanzees possessed all ten epitopes examined but the orangutan lacked Leu4 and Leu7 epitopes and the gibbons lacked Leu4, Leu7, and Leu12 epitopes. In addition to the above epitopes, the Old World monkeys lacked Leu1 and Leu10 epitopes. The Leu3a/Leu2a cell ratios varied from 0 to 1.56 among the 12 macaque species and this enabled classification of these species into three groups. In the New World monkeys, Leu2a epitope was absent, whereas Leu11a epitope was detected in several species and Leu3a epitope was found only in the owl monkeys. The prosimians expressed only HLA-DR epitope. 相似文献
39.
Summary Human, bovine and canine articular chondrocytes have been shown to bear cartilage matrix, chondrocyte-specific and histocompatibility antigens. These cell-surface antigens of chondrocytes were demonstrated both simultaneously and separately either by complement-mediated cytotoxicity or by immunohistochemical reactions. The chondrocyte-specific antigens involve subsets of species-common and species-specific determinants, which are also present on the surfaces of rib and laryngeal chondrocytes. In addition to these antigens, human and calf articular chondrocytes also express unique cell-surface components that are capable of producing a blastogenic stimulation of autologous T-lymphocytes in vitro. These putative autoantigens segregated from lymphocytes in vivo could be released in trauma and in inflammatory joint diseases triggering the immune system of the host. 相似文献
40.
Host receptor sites involved in the attachment of Bdellovibrio bacteriovorus and Bdellovibrio stolpii 总被引:1,自引:0,他引:1
Abstract The location of lipoteichoic acid and 3 cell wall-associated protein antigens in fresh isolates of Streptococcus mutans (serotype c ) and in variants derived from these parental strains by repeated subculture in vitro has been examined by electrophoretic and dot-immunobinding techniques. Following subculture there was a marked shift in the distribution of all four antigens from the cell wall to the extracellular culture supernatants. It is therefore apparent that that the decreased hydrophobicity and the impaired ability of the subcultured variants to colonise in vivo, as observed by others, cannot be correlated with changes in a single surface molecule. 相似文献