scholarly journals The protein antigens secreted in vivo by adult male Schistosoma mansoni

Parasitology ◽  
1997 ◽  
Vol 114 (3) ◽  
pp. 245-255 ◽  
Author(s):  
L. CUTTS ◽  
R. A. WILSON

Adult schistosomes can be transferred surgically from donor C57BL/6 mice to the portal veins of naive recipients with complete success. This procedure bypasses larval development and the antibody response of the host is directed against, and can be used to identify, those antigens released only by viable, mature parasites. Serum collected from the recipient mice (WTS) was used in Western blotting studies to probe fractionated parasite protein. Twelve immunodominant proteins were identified, ranging in molecular weight from 14 to 208 kDa. The magnitude of the IgG response against each antigen could be divided into 2 categories, on the basis of optical densitometry of the blots. In addition, defined parasite fractions were probed with WTS by Western blotting, in order to determine the relative abundance and distribution of each antigen in schistosome tissue. To confirm and expand on these initial observations, oligospecific polyclonal antibody for each immunogen was affinity purified from Western blots; it was then used in immunocytochemistry to identify the sources of secretion for 8 of the 12 antigens, at the cellular level. From the results, it appeared that after the transfer of adult worms, the first antibodies detected were mostly directed against the gastrodermis. At later times additional reactivity was expressed against the tegumental membrane. These differences probably reflect the relative abundances of the gut and tegumental secretory products.

Blood ◽  
1995 ◽  
Vol 86 (1) ◽  
pp. 283-293 ◽  
Author(s):  
R Ford ◽  
A Tamayo ◽  
B Martin ◽  
K Niu ◽  
K Claypool ◽  
...  

The molecular basis of neoplastic B-cell growth is complex and poorly understood. Cytokines have been postulated to contribute to neoplastic cell growth, and many in vitro studies have confirmed this prediction, but little is known about the in vivo role of these growth factors. We have examined the production of interleukin-14 (IL-14) (high molecular weight [HMW], B-cell growth factor [BCGF]) by aggressive intermediate (diffuse large cell) lymphomas of the B-cell type non-Hodgkin's lymphoma (NHL-B) in four patients with lymphomatous effusions. In these studies, IL-14 was detected in the effusion fluids by Western blots and IL-14 mRNA was constitutively expressed in the freshly isolated lymphoma cells that also expressed the receptor for IL-14 (IL14R). Lymphoma B cells placed at low serum and cell density proliferated in vitro to either purified IL-14 or IL-14 derived from effusion fluids. Antibodies to IL-14 removed the growth-stimulating cytokine(s) from the effusions. Cell lines developed from these patients produced IL-14 in vitro and antisense oligos to IL-14 blocked their growth in vitro. Thus, autocrine or paracrine production of IL-14 may play a significant role in the rapid proliferation of aggressive NHL-B. Interrupting this pathway could be a useful goal of therapy for patients resistant to conventional chemotherapy.


1982 ◽  
Vol 156 (5) ◽  
pp. 1312-1324 ◽  
Author(s):  
A G Barbour ◽  
S L Tessier ◽  
H G Stoenner

Borrelia hermsii, a relapsing fever agent, manifests antigenic variation in vivo and in vitro. We studied three mouse-passaged serotypes of strain HS1 (7, 14, and 21) and a HS1 derivative obtained after multiple in vitro passages (C serotype). All four serotypes had two major proteins in whole cell lysates fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. One major protein species (pII) had the same apparent subunit molecular weight (or approximately 3.9 X 10(4) in all the serotypes. In contrast, the other abundant protein in lysates, pI, had a different apparent molecular weight in each serotype. In one gel the molecular weights of pIc, pI7, pI14, and pI21 were 1.9, 4.2, 4.1, and 4.0 X 10(4), respectively. Serotype-specific mouse antisera bound to both hemologous and heterologous pIIs, to homologous pI, but not to heterologous pI in Western blots. Hybridomas were raised from spleens of mice infected with B. hermsii. Monoclonal antibodies were identified by immunofluorescence assays using whole organisms. Monoclonal antibodies specific for serotype 7 (H1826) or for serotype 21 (H3326) bound only to pI7 or pI21, respectively, in Western blots. The surface location of the pI was suggested not only by the immunofluorescence studies but also by the labeling of pI7 and pI21 when whole cells of serotypes 7 and 21 were incubated with 125I in the presence of Iodogen. Under the same circumstances, pII was relatively poorly labeled. These studies have identified the variable pI proteins of B. hermsii as serotype-specific antigens. A change from one pI to another may be the basis of antigenic variation of Borrelia species during relapsing fever.


2021 ◽  
Author(s):  
Cameron O Zadeh ◽  
Jonah R Huggins ◽  
Baylee C Westbury ◽  
William R Interiano ◽  
S Ashley Phillips ◽  
...  

Western blotting is a widely-used technique for molecular-weight-resolved analysis of proteins and their post-translational modifications, but has been refractory to affordable scale-up. Here, we report the Mesowestern blot, which uses a 3D-printable gel-casting mold to enable affordable, high-throughput Western blotting with standard sample preparation and small (<1 uL) sample sizes. The casted polyacrylamide gel contains 336, 0.5 uL micropipette-loadable sample wells arranged within a standard microplate footprint. Polyacrylamide % can be altered to change molecular weight resolution range. Proof-of-concept experiments using both infrared-fluorescent molecular weight protein ladder as well as cell lysate (RIPA buffer) demonstrate protein loaded in Mesowestern gels is amenable to the standard Western blotting steps. The main difference between Mesowestern and traditional Western is that semi-dry horizontal instead of immersed vertical gel electrophoresis is used. The linear range of detection is approximately 2 orders of magnitude, with a limit of detection (for beta-actin) of around 30 ng of total protein from mammalian cell lysates (~30-3000 cells). Because the gel mold is 3D-printable, users have significant design freedom for custom layouts, and there are few barriers to adoption by the typical cell and molecular biology laboratory already performing Western blots.


2005 ◽  
Vol 51 (10) ◽  
pp. 1933-1945 ◽  
Author(s):  
Mark S Lowenthal ◽  
Arpita I Mehta ◽  
Kristina Frogale ◽  
Russell W Bandle ◽  
Robyn P Araujo ◽  
...  

Abstract Background: Albumin binds low–molecular-weight molecules, including proteins and peptides, which then acquire its longer half-life, thereby protecting the bound species from kidney clearance. We developed an experimental method to isolate albumin in its native state and to then identify [mass spectrometry (MS) sequencing] the corresponding bound low–molecular-weight molecules. We used this method to analyze pooled sera from a human disease study set (high-risk persons without cancer, n= 40; stage I ovarian cancer, n = 30; stage III ovarian cancer, n = 40) to demonstrate the feasibility of this approach as a discovery method. Methods: Albumin was isolated by solid-phase affinity capture under native binding and washing conditions. Captured albumin-associated proteins and peptides were separated by gel electrophoresis and subjected to iterative MS sequencing by microcapillary reversed-phase tandem MS. Selected albumin-bound protein fragments were confirmed in human sera by Western blotting and immunocompetition. Results: In total, 1208 individual protein sequences were predicted from all 3 pools. The predicted sequences were largely fragments derived from proteins with diverse biological functions. More than one third of these fragments were identified by multiple peptide sequences, and more than one half of the identified species were in vivo cleavage products of parent proteins. An estimated 700 serum peptides or proteins were predicted that had not been reported in previous serum databases. Several proteolytic fragments of larger molecules that may be cancer-related were confirmed immunologically in blood by Western blotting and peptide immunocompetition. BRCA2, a 390-kDa low-abundance nuclear protein linked to cancer susceptibility, was represented in sera as a series of specific fragments bound to albumin. Conclusion: Carrier-protein harvesting provides a rich source of candidate peptides and proteins with potential diverse tissue and cellular origins that may reflect important disease-related information.


Parasitology ◽  
1997 ◽  
Vol 114 (3) ◽  
pp. 257-262 ◽  
Author(s):  
Z. M. NOR ◽  
K. M. HOUSTON ◽  
E. DEVANEY ◽  
W. HARNETT

The mechanism of linkage of phosphorylcholine (PC) to excretory–secretory products (ES) of adult Brugia pahangi has been investigated. Biosynthetic radio-isotope labelling of ES with [3H]choline followed by SDS–PAGE/fluorography revealed a smear of molecular weight approximately 40–100 kDa which loses its radiolabel following exposure to N-glycosidase F, but not mild alkali. PC is thus attached to this smear of molecules via N-type glycans, a mechanism of linkage previously observed with respect to PC–ES of Acanthocheilonema viteae. Western blotting analysis of non-radiolabelled ES demonstrated the existence of additional PC–ES which were insensitive to N-glycosidase F, but not to alkali. This second group of molecules is therefore likely to contain PC linked to O-glycans. Filarial nematodes may thus utilize 2 classes of glycan for attachment of PC. Examination of B. pahangi and A. viteae whole worm extracts by Western blotting indicated that their PC content could not be cleaved by N-glycosidase F and hence the use of N-type glycans may be restricted to a subset of ES products. The implications of these findings with respect to developing inhibitors of PC attachment for use as anti-filarial drugs are discussed.


Author(s):  
J. D. Shelburne ◽  
Peter Ingram ◽  
Victor L. Roggli ◽  
Ann LeFurgey

At present most medical microprobe analysis is conducted on insoluble particulates such as asbestos fibers in lung tissue. Cryotechniques are not necessary for this type of specimen. Insoluble particulates can be processed conventionally. Nevertheless, it is important to emphasize that conventional processing is unacceptable for specimens in which electrolyte distributions in tissues are sought. It is necessary to flash-freeze in order to preserve the integrity of electrolyte distributions at the subcellular and cellular level. Ideally, biopsies should be flash-frozen in the operating room rather than being frozen several minutes later in a histology laboratory. Electrolytes will move during such a long delay. While flammable cryogens such as propane obviously cannot be used in an operating room, liquid nitrogen-cooled slam-freezing devices or guns may be permitted, and are the best way to achieve an artifact-free, accurate tissue sample which truly reflects the in vivo state. Unfortunately, the importance of cryofixation is often not understood. Investigators bring tissue samples fixed in glutaraldehyde to a microprobe laboratory with a request for microprobe analysis for electrolytes.


1994 ◽  
Vol 72 (06) ◽  
pp. 942-946 ◽  
Author(s):  
Raffaele Landolfi ◽  
Erica De Candia ◽  
Bianca Rocca ◽  
Giovanni Ciabattoni ◽  
Armando Antinori ◽  
...  

SummarySeveral “in vitro” and “in vivo” studies indicate that heparin administration may affect platelet function. In this study we investigated the effects of prophylactic heparin on thromboxane (Tx)A2 biosynthesis “in vivo”, as assessed by the urinary excretion of major enzymatic metabolites 11-dehydro-TxB2 and 2,3-dinor-TxB2. Twenty-four patients who were candidates for cholecystectomy because of uncomplicated lithiasis were randomly assigned to receive placebo, unfractionated heparin, low molecular weight heparin or unfractionaed heparin plus 100 mg aspirin. Measurements of daily excretion of Tx metabolites were performed before and during the treatment. In the groups assigned to placebo and to low molecular weight heparin there was no statistically significant modification of Tx metabolite excretion while patients receiving unfractionated heparin had a significant increase of both metabolites (11-dehydro-TxB2: 3844 ± 1388 vs 2092 ±777, p <0.05; 2,3-dinor-TxB2: 2737 ± 808 vs 1535 ± 771 pg/mg creatinine, p <0.05). In patients randomized to receive low-dose aspirin plus unfractionated heparin the excretion of the two metabolites was largely suppressed thus suggesting that platelets are the primary source of enhanced thromboxane biosynthesis associated with heparin administration. These data indicate that unfractionated heparin causes platelet activation “in vivo” and suggest that the use of low molecular weight heparin may avoid this complication.


1993 ◽  
Vol 70 (03) ◽  
pp. 438-442 ◽  
Author(s):  
B Grøn ◽  
C Filion-Myklebust ◽  
S Bjørnsen ◽  
P Haidaris ◽  
F Brosstad

SummaryFibrinogen and fibrin related chains in reduced human plasma as well as the bonds interlinking partially cross-linked fibrin from plasma clots have been studied by means of 1D- and 2D electrophoresis and Western blotting. Immunovisualization of reduced plasma or partially cross-linked fibrin with monoclonal antibodies specific for the α-chains or the γ-chains have shown that several bands represent material belonging to both chains. In order to decide whether these bands constitute αγ-chain hybrids or superimposed α- and γ-chain dimers, the cross-linked material was separated according to both isoelectric point (pI) and molecular weight (MW) using Pharmacia’s Multiphor II system. Western blotting of the second dimension gels revealed that partially cross-linked fibrin contains αsγt-chain hybrids and γ- polymers, in addition to the well-known γ-dimers and α-polymers. The main αsγt-chain hybrid has a pI between that of the α- and the γ-chains, a MW of about 200 kDa and contains Aα-chains with intact fibrinopeptide A (FPA). It was also observed that soluble fibrinogen/fibrin complexes as well as partially cross-linked fibrin contain degraded α-dimers with MWs close to the γ-dimers. These findings demonstrate that factor XIII-catalyzed cross-linking of fibrin is a more complex phenomenon than earlier recognized.


1981 ◽  
Vol 46 (03) ◽  
pp. 612-616 ◽  
Author(s):  
U Schmitz-Huebner ◽  
L Balleisen ◽  
F Asbeck ◽  
J van de Loo

SummaryHigh and low molecular weight heparin fractions obtained by gel filtration chromatography of sodium mucosal heparin were injected subcutaneously into six healthy volunteers and compared with the unfractionated substance in a cross-over trial. Equal doses of 5,000 U were administered twice daily over a period of three days and heparin activity was repeatedly controlled before and 2, 4, 8 hrs after injection by means of the APTT, the anti-Xa clotting test and a chromogenic substrate assay. In addition, the in vivo effect of subcutaneously administered fractionated heparin on platelet function was examined on three of the volunteers. The results show that s.c. injections of the low molecular weight fraction induced markedly higher anti-Xa activity than injections of the other preparations. At the same time, APTT results did not significantly differ. Unfractionated heparin and the high molecular weight fraction enhanced ADP-induced platelet aggregation and collagen-mediated MDA production, while the low molecular weight fraction hardly affected these assays, but potently inhibited thrombin-induced MDA production. All heparin preparations stimulated the release of platelet Factor 4 in plasma. During the three-day treatment periods, no side-effects and no significant changes in the response to heparin injections were detected.


1964 ◽  
Vol 12 (01) ◽  
pp. 232-261 ◽  
Author(s):  
S Sasaki ◽  
T Takemoto ◽  
S Oka

SummaryTo demonstrate whether the intravascular precipitation of fibrinogen is responsible for the toxicity of heparinoid, the relation between the toxicity of heparinoid in vivo and the precipitation of fibrinogen in vitro was investigated, using dextran sulfate of various molecular weights and various heparinoids.1. There are close relationships between the molecular weight of dextran sulfate, its toxicity, and the quantity of fibrinogen precipitated.2. The close relationship between the toxicity and the precipitation of fibrinogen found for dextran sulfate holds good for other heparinoids regardless of their molecular structures.3. Histological findings suggest strongly that the pathological changes produced with dextran sulfate are caused primarily by the intravascular precipitates with occlusion of the capillaries.From these facts, it is concluded that the precipitates of fibrinogen with heparinoid may be the cause or at least the major cause of the toxicity of heparinoid.4. The most suitable molecular weight of dextran sulfate for clinical use was found to be 5,300 ~ 6,700, from the maximum value of the product (LD50 · Anticoagulant activity). This product (LD50 · Anticoagulant activity) can be employed generally to assess the comparative merits of various heparinoids.5. Clinical use of the dextran sulfate prepared on this basis gave satisfactory results. No severe reaction was observed. However, two delayed reactions, alopecia and thrombocytopenia, were observed. These two reactions seem to come from the cause other than intravascular precipitation.


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