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PubMed1985

A comparative immunological investigation of the alkane hydroxylating cytochrome P-450 from the yeast Candida maltosa.

The immunological relations of the cytochrome P-450 from the n-alkane utilizing yeast Candida maltosa to cytochrome P-450 forms of other organisms - yeasts, bacteria and mammalia - were investigated using a solid-phase double-antibody radioimmunoassay. Only the microsomal fraction of other n-alkane utilizing yeasts shows a distinct cross-reaction with an antiserum against cytochrome P-450 from Candida maltosa. Neither the tested bacterial nor the mammalian cytochromes P-450 cross-react with the antiserum.

Alkanes↗
PubMed1988

Comparative immunological and electrophoretic analysis of Gc protein in sera from various animals.

1. On immunodiffusion, using an anti-human Gc antibody, serum Gc in all mammals tested revealed a partial identity with human Gc. 2. The relative cross-reactivities of serum Gc in monkeys, dogs, cats and rats with human Gc antiserum were found to be more than 70% while the serum Gc in other mammals (pigs, cattle, goats and a guinea pig) was less than 50%. 3. Testing, using the isoelectrofocusing method, showed specific patterns of Gc in the mammals. In the sera of cats and cattle, Gc polymorphisms were detected. 4. Neuraminidase treatment affected the isoelectrofocusing Gc patterns of pigs, goats and cattle, whereas those in other mammals remained unchanged.

Alleles↗
PubMedDate not supplied

Comparative immunological detection of lipids and carotenoids on peptides of photosystem I from higher plants and cyanobacteria.

Photosystem I preparations were obtained from wild-type tobacco Nicotiana tabacum var. JWB, three chlorophyll-deficient tobacco mutants: Su/su, Su/su var. Aurea and yellow-green leaf patches of the variegated mutant NC 95, Spinacia oleracea and furthermore from the mesophilic cyanobacterium Synechococcus PCC 7942 and the thermophilic cyanobacterium Synechococcus sp.. Peptides from these preparations were analyzed by SDS polyacrylamide gel electrophoresis and transferred for detection of bound lipids and carotenoids according to the Western blot procedure to nitrocellulose membranes. The PS I preparations from the Nicotiana tabacum species and spinach consist of the core complex and the LHCP I complex, the latter containing, however, traces of the LHCP II polypeptides. The core complex consists of the two core peptides with the apparent molecular mass of 66 kDa each and peptides with molecular masses of 22, 20, 19, 17, 16, 10 and 9 kDa. The LHCP I complex contains 4 subunits with molecular masses of 28, 26, 25 and 24 kDa. The PS I preparations of the two mutants Su/su and Su/su var. Aurea contain as impurities traces of the core peptides (D1/D2) and the two chlorophyll-binding peptides (CP43/CP47) of photosystem II. The PS I preparation from the mesophilic and thermophilic cyanobacterium consists of the two core peptides with the apparent molecular mass of 66 kDa and peptides with molecular masses of 16, 14 and 10 kDa. The peptides of the PS I preparations were characterized by specific PS I, CP I and LHCP I antisera. The antiserum to the PS I complex reacts in the Western blot with the homologous peptides of PS I from higher plants, but only with the CP I complex from the two cyanobacteria. In comparative studies with PS II from higher plants the PS I antiserum reacts with the LHCP II complex as expected. The antiserum to the CP I complex reacts only with the 66 kDa peptides of PS I from all objects. There is no cross reaction with the 66 kDa peptides (heterodimer of the D1/D2 peptides) of PS II. The antiserum to the LHCP I complex reacts only with the four LHCP I peptides of PS I from higher plants and as expected with the LHCP II of PS II: Because cyanobacteria do not have LHCP complexes, there is no reaction with the LHCP I antiserum. By means of polyclonal monospecific antisera to lipids it was shown by Western blot procedure that only two lipid species are bound to PS I peptides. The galactolipid monogalactosyldiglyceride is bound to the CP I complex of the Nicotiana tabacum species, spinach and the two cyanobacteria as well as to the LHCP I complex of the higher plants. The phospholipid phosphatidylglycerol is only associated with the CP I complex of the analyzed higher plants and cyanobacteria. With polyclonal monospecific antisera to carotenoids it was demonstrated that beta-carotene, lutein, neoxanthin and zeaxanthin are associated with the CP I complex of the higher plants and the cyanobacteria analyzed. Violaxanthin is also bound to the CP I complex of the two cyanobacteria, whereas it is bound together with neoxanthin to the LHCP I complex of the higher plants.

Animals↗
PubMedDate not supplied

Comparative immunological and chemical analysis of lipids and carotenoids of the D1-peptide and of the light-harvesting-complex of photosystem II of Nicotiana tabacum.

The light-harvesting-complex (LHCP) was isolated from photosystem II of Nicotiana tabacum var. John William's Broadleaf by means of the detergent acetyl-beta-D-glucopyranoside and fractionating centrifugation. The D1-peptide of photosystem II was isolated as a dimer with the molecular mass of 66 kDa from the chlorophyll-deficient tobacco mutant N. tabacum Su/su by means of sodium dodecyl sulfate polyacrylamide gel electrophoresis. Both preparations were characterized by means of the Western blot procedure using monospecific antisera to the proteins of photosystem II and monospecific antisera to lipids with which the lipids bound to peptides were determined. In parallel to this, lipids bound to the isolated LHCP-complex and to the isolated D1-peptide were determined by lipido-chemical methods. The extraction of the isolated core peptide D1 with a mixture of boiling methanol and chloroform and subsequent HPLC-chromatography showed that in the D1-peptide isolated via SDS-polyacrylamide gel electrophoresis, monogalactolipids, phosphatidylglycerol and sulfolipid molecules are bound in the molar ratio 1:3:17. By means of the immunological procedure of Western blotting we were able to show that the 66 kDa band of the isolated dimeric D1 reacts positively only with the antisera to monogalactolipid, sulfolipid, beta-carotene and violaxanthin. With the antiserum to digalactolipid and that to phosphatidylglycerol a positive reaction is only observed if the preparation used in the Western blot is not the isolated D1-peptide but a "total" photosystem II-preparation. The lipid extraction of the LHCP-complex and the subsequent analysis by thin-layer chromatography led to the result that the isolated LHCP complex contained in bound form 3 molecules monogalactolipid, 1 molecule of digalactolipid, 1 molecule of phosphatidylglycerol and 1 molecule of lutein. Less than 1 molecule of sulfolipid, beta-carotene, neoxanthin and violaxanthin are found. In the Western blot analysis only the antiserum to monogalactolipid and phosphatidylglycerol and among the carotenoid antisera only the antisera to beta-carotene, violaxanthin and to neoxanthin reacted. With the antisera to the digalactolipid, to the sulfolipid and the antisera to the xanthophylls, namely to lutein and neoxanthin, a positive reaction occurred only if the material used in the Western Blot was the "total" photosystem II-preparation. By gas chromatography of the fatty acids of the isolated peptide fractions it was shown that, compared to the lipids of photosystem II and of the thylakoid membrane, in lipids of the isolated D1-peptide and of the LHCP-complex the saturation degree of fatty acids is strongly increased. Whereas palmitic acid in chloroplast lipids makes up for only 11% of the fatty acids, this saturated fatty acid increases in the lipids of the LHCP to 20% and makes up for 74% of total fatty acids in the lipids of the D1-peptide. Linoleic and linolenic acids are completely absent and oleic acid makes up for 14% of total fatty acids. In contrast to the lipids of the thylakoid membrane, the lipids bound to proteins/peptides are characterized by a strongly saturated character.

Antibodies↗
PubMed1983

A comparative immunologic study of IgA nephropathy.

A conglutinin binding assay has been used to detect circulating immune complexes (CIC) containing IgA, IgG, or IgM in sera from patients with IgA nephropathy. IgA class CIC were detected in 40.7% of patient. IgG class CIC were detected only in patients with glomercular IgG deposits. IgM class CIC were detected more often in patients with glomerular IgM deposits than in patients without glomerular IgM deposits. These results demonstrate an association between the immunoglobulin in CIC and those in glomerular deposits. CIC were not detected in sera from most patients with IgA nephropathy by a Clq binding assay, however, since this assay does not detect IgA class CIC. Immunoelectronmicroscopic studies of IgA nephropathy have shown that C3 deposits are localized to the same areas as IgA deposits. In conclusion, we suggest that mesangial IgA deposits are composed of immune complexes and may be derived from CIC.

Antigen-Antibody Complex↗
PubMed1978

Comparative immunological studies in ITP.

Twelve splenectomized and 16 non-splenectomized patients with ITP were studied for autoimmune complement fixation (AICF), indirect immunofluorescence (IF), platelet "immuno-injury" (T-3), antinuclear antibody (ANA), and serum electrophoresis. AICF was found positive in 50%, IF in 81%, T-3 in 50%, ANA in 69% of splenectomized cases. No significant difference in any of above parameters or in the gamma globulin levels was found between the splenectomized and the non-splenectomized groups. These observations are less favourable than those reported by other workers in post-splenectomy cases of ITP. The results, in agreement with those of earlier lymphocyte-transformation studies of the authors, are consistent with the primary mechanical role of the spleen in ITP, and make it justified to connect the failure of ITP to respond adequately to splenectomy, and the persistent seropositivity in these cases, with an excessive IgG production by the bone marrow.

Adolescent↗
PubMedDate not supplied

[Comparative immunological analysis of echinoderm cellular and humoral defense factors].

Coelomocyte are found in the fluid filling coelomic cavity of echinoderms and depending on species can be a mixture of several morphologically different types. There are among them: granular and agranular amoebocytes, morula cells, vibratile and lymphocyte-like cells. All these cells take part in cellular response to immune challenges through phagocytosis, clotting, encapsulation of foreign particles, cytotoxicity, and the production of antimicrobial agents, such as reactive oxygen and nitric oxide. The data are given on a variety of humoral factors found in the coelomic fluid, including different types of lectines, agglutinins, hemolysins, acute phase proteins and antimicrobial factors. The discussion on cooperation between cellular and humoral arms of defense reactions during inflammation reveals the crucial role of coelomocytes in immune response. It is suggested that the sea urchin complement system (that is homologous to the alternative pathway in vertebrates) is appeared initially in echinoderms as a protein cascade that points to opsonization of foreign cells and particles, augmenting their phagocytosis and subsequent destruction by coelomocytes. So the identification of a simple complement system as a part of the echinoderm immune response shows that these animals as well as all invertebrate deuterostomes share innate immune system homologies with vertebrates. Studying the simpler immune response demonstrated by echinoderms is important for understanding the ancestral deuterostome defense system and reconstructing the evolution of immune system in higher vertebrates.

Animals↗
PubMed1996

Comparative immunological and genomic characterization of fowlpox virus isolates.

Chickens infected with fowlpox virus (FPV) IVRI vaccine strain and two field isolates collected from clinical cases of disease (Bareilly isolate and Panchmahal isolate) produced humoral antibody response after 2nd week post-infection, with a noticeable variation in degree of immune response. Serum antibody titre peaked at 4th week post-infection with a titre of 25,600, 25,600 and 51,200 being detected in ELISA and neutralization index of 2.75, 2.43 and 3.12 in serum neutralization test (SNT) with IVRI vaccine strain, Panchmahal isolate and Bareilly isolate, respectively. Cellular immune response was detected as early as 1st week post-infection by leukocyte migration inhibition test (LMIT). Per cent migration inhibition too peaked at 4th week with a value of 40.30 +/- 3.45, 36.93 +/- 4.11 and 45.45 +/- 3.66 being detected with the three viruses respectively. The Hind III and Hae III restriction fragment profile of viral DNA showed almost similar pattern both in vaccine strain and two field isolates. Hind III digestion produced 47 well resolved fragments of sizes between 24.30 and 1.20 kb and the total genomic size was estimated to be between 305.81 and 306.06 kb. Hae III digestion revealed 34 well resolved fragments of sizes between 27.55 and 1.32 kb. The three viruses could not be differentiated on the basis of their genomic restriction pattern. However immunogenic and antigenic differences were noticed by ELISA and SNT tests.

Animals↗
PubMed1994

Comparative immunological characterization of type-specific and conserved B-cell epitopes of pinniped, felid and canid herpesviruses.

Murine monoclonal antibodies (MAbs) were generated against phocid herpesviruses (PhHV 2557/Han88 and 7848/Han90) isolated from European harbour seals (Phoca vitulina), and against strains of both felid (FHV strain FVR 605) and canid herpesviruses (CHV isolate 5105/Han89). MAbs were characterized with respect to certain biological properties and used to outline antigenicity profiles of isolates of PhHV (n = 8), FHV (n = 7) and CHV (n = 3) in enzyme immunoassays employing fixed infected cells. A close antigenic relationship between herpesviruses derived from pinnipeds and terrestrial carnivores became evident: The majority of the MAbs was directed against epitopes which were expressed by at least two of the viral species tested. A number of MAbs detected epitopes which were conserved between all isolates of PhHV, FHV and CHV. A few MAbs recognized type-specific B-cell epitopes and facilitated the identification of single viral species. Moreover, the PhHV isolate 7848/Han90 was antigenically distinguishable both from seven other phocid herpesvirus isolates and from FHV or CHV. PhHV 7848/Han90 proved to be antigenically distinct from all other viruses tested when examined by cross neutralization utilizing various reconvalescent and hyperimmune sera. Although more data are needed to ensure that PhHV 7848/Han90 indeed is a new genuine seal herpesvirus, the preliminary clustering of two groups of phocid herpesvirus isolates, tentatively designated PhHV-1 (type isolate 2557/Han88) and PhHV-2 (represented by 7848/Han90), seems to be justified. By using selected MAbs an unambiguous identification and typing of herpesvirus isolates derived from marine mammals and terrestrial carnivores is significantly facilitated.

Alphaherpesvirinae↗
PubMed1983

Comparative immunological and biochemical analyses of viruses in the Venezuelan equine encephalitis complex.

Unclassified Venezuelan equine encephalitis (VEE) viruses Tonate (TON), Bijou Bridge (BB), Paramana (PARA), 71D-1252 and Cabassou (CAB) were characterized serologically and biochemically. The envelope glycoproteins of these and nine other VEE viruses representing VEE subtype variants I-AB, I-C, I-D, I-E, II, III and IV were separated by column isoelectric focusing. The E1 and E2 glycoproteins of all the Zwittergent-dissociated VEE viruses focused at pI 6.3 to 6.9 and pI 8.6 to 9.3 respectively. Haemagglutination-inhibition and neutralization tests using rabbit sera to the E2 glycoprotein of TON, BB and PARA viruses showed them to be indistinguishable from each other and closely related to prototype subtype III virus Mucambo (MUC). VEE strain 71D-1252 was also serologically closely related to prototype MUC virus. We proposed that MUC, TON and 71D-1252 VEE viruses be classified subtype III viruses, designated variants III-A, III-B and III-C respectively. CAB virus, which is not closely related to other VEE isolates, may represent a new VEE subtype (V). SDS-PAGE resolved the capsid protein (35 to 36 kdal) and two major envelope glycoproteins of 50 to 51 kdal (E1) and 51 to 58 kdal (E2) for all VEE viruses except CAB; the two glycoproteins of CAB virus co-migrated by PAGE with apparent identical mol. wt. of 51 kdal. Limited digestion of SDS-dissociated virus proteins with Staphylococcus aureus V8 protease produced identical peptide maps for serologically indistinguishable viruses. Oligonucleotide fingerprinting of virus RNA supported the close serological relationships observed at the genome level.

Capsid↗
PubMed1978

Comparative immunological analysis of host plasma proteins bound to bloodstream forms of Trypanosoma brucei subspecies.

The presence, location, host specificity, identity, and quantity of rat plasma proteins bound to bloodstream forms of Trypanosoma brucei subsp. brucei, T. brucei subsp. rhodesiense, and T. brucei subsp. gambiense were determined by a quantitative indirect fluorescent-antibody method and gel immunoassays. Fluorescence differences between trypanosomes obtained from rats and mice and treated with antiserum to normal rat plasma indicated that most, if not all, of the bound plasma proteins were host specific. Removal of plasma proteins by trypsinization of parasites provided evidence for their attachment to the surface of the parasite. The accreted proteins were found to be host albumin, immunoglobulin G (IgG), and complement (C3). The same quantities of these three plasma proteins were present on T. brucei subspecies collected from normal rats at 2 days postinfection, during low or peak parasitemias, or from cortisone-treated rats. IgM could only be detected on parasites collected from normal rats at peak parasitemia. With the aid of rocket immunoelectrophoresis, host albumin and IgG were found to account for 0.2 and 0.05%, respectively, of the total soluble proteins of the bloodstream forms. It was concluded from this study that: (i) host plasma proteins were bound to parasites early in the infection, suggesting a mechanism of adaptation to the mammalian host; (ii) the surface-bound IgG was not the result of a specific immune response against the parasites but might be the cause of C3 attachment; (iii) among the bloodstream forms of the three T. brucei subspecies, there were no differences in amounts of surface-bound albumin, IgG, or C3. A comparison between the present data dealing with T. brucei subspecies, on the one hand, and the previously published results concerning T. congolense, on the other, revealed significant differences in the amounts of the host plasma proteins attached to these hemoflagellates.

Animals↗
PubMed1979

Relatedness among coagulase-negative staphylococci: deoxyribonucleic acid reassociation and comparative immunological studies.

DNA-DNA-homology values were determined under restrictive to relaxed reassociation conditions with type strains and some additional strains of coagulase-negative staphylococci belonging to ten different species. The immunological relationship of the catalases present in the type strains of these species was also determined by applying double immunodiffusion and microcomplement fixation. The results of these studies support the previous proposal to subdivide the coagulase-negative staphylococci into at least ten separate species. However, it is evident that some of the species are more closely realted than others and can form species groups. According to the results presented in this study, the coagulase-negative staphylococci can be combined into five species groups: The Staphylococcus saprophyticus group is composed of S. saprophyticus, S. xylosus and S. cohnii. The S. epidermidis group comprises S. epidermis, S. capitis and S. warneri. The S. hominis group which exhibits a significant relationship to S. epidermidis includes S. hominis and S. haemolyticus. The species group S. sciuri consists of S. sciuri ssp. sciuri and S. sciuri ssp. lentus and the species group S. simulans is presently represented by the corresponding single species.

Catalase↗
PubMed1979

A comparative immunological study of catalases from coagulase-positive staphylococci.

Protein homology studies with catalase as a reference point were carried out with coagulase-positive staphylococci belonging to Staphylococcus aureus, S. intermedius and S. hyicus. Antisera against catalases of S. aureus ATCC 12600 and S. aureus ATCC12601 reacted very weakly employing double immunodiffusion and quantitative microcomplement-fixation assay with cell-free extracts or catalase enriched preparations of S. intermedius or S. hyicus. The differences between coagulase-positive staphylococci could be confirmed by using the antiserum against S. intermedius H 11 catalase. Within the strains of the species S. intermedius immunological distances ranging up to 25 indicate a heterogeneity which justify the separation of the biotypes E and F on a subspecies level. Coagulase-positive strains of S. hyicus revealed neither a close relationship to S. aureus nor to S. intermedius.

Animals↗