Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0393754 (HSA)
 2,996 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Staphylococcus epidermidis peptidoglycans solubilized by sonication or lysozyme digestion, and synthetic peptidoglycan analogs such as HSA-carboxymethyl-Gly-L-Ala-L-Ala-D-Ala-D-Ala (HSA-pentapeptide) or L-Ala-gamma-D-Glu-L-Lys-D-Ala-D-Ala (pentapeptide) have been labeled with 125I and tested for their applicability in the radioactive antigen binding assay. Use of radioiodinated Staph. epidermidis peptidoglycans was found to be considerably impeded by the presence of at least 2 different antigenic sites on such molecules, the pentapeptide and the glycan determinant. Application of labeled HSA-pentapeptide was limited by the necessity to use PEG for precipitation of Ag-Ab-complexes and by short linear potions of binding curves. However, the synthetic pentapeptide hapten, radioiodinated by the active ester method of BOLTON and HUNTER, proved to be a most useful regent for the selective measurement of pentapeptide antibody. Inhibition studies indicated that the immunological specificity of the labeled hapten was retained. Pentapeptide binding curves were linear from 15-500 g/ml of antibody. Generally, there was good agreement between pentapeptide antibody concentrations measured by radioimmunoassay and quantitative precipitation.
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PMID:Measurement of peptidoglycan antibodies by a radioimmunoassay. 5 37

The effect of related and unrelated compounds on the specific binding of dinitrophenyl-coupled bacteriophage (DNP-T4) to lymphoid cell receptors has been examined and compared with the effect on the neutralization of DNP-T4 by anti-DNP serum. Spleen cells and sera from Balb/c mice immunized with DNP-bovine serum albumin were used. The binding of DNP-T4 to the cells was inhibited by DNP-eAcp, di-DNP-Lys, DNP-Tyr, DNP-p(Ornith) and DNP-BSA (among the DNP-derivatives tested), TNP-BSA, ARS-p(Tyr) and TGA. In addition with the above named DNP and TNP compounds, the DNP-T4neutralization by antiserum was also prevented by DNP-derivatives with either L-cysteic acid, alanine, glutamine or poly-L-glutamic acid, while ARS-p(Tyr) and TGA were not effective. Plain carriers (BSA, HSA, poly-ornithine, polylysine and polyglutaminc acid) and cell-mitogens (ConA, LPS and PPD) had no significant inhibitory effect. The results obtained indicate the occurrence of differences between cell-bound receptors and circulating antibodies in what concerning their specific reaction with the dinitrophenyl determinant.
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PMID:Inhibition of specific binding of DNP (dinitrophenyl) determinant to lymphoid-cell receptors by related and unrelated compounds : quantitative studies in vitro. 6 Sep 7

Carp anti-DNP antibodies were raised by various DNP-carrier conjugates. Their intrinsic affinity (K0) to monovalent E-DNP-L-lysine and functional affinity (DF) for binding to the multivalent DNP-T4 bacteriophages were determined. The functional affinity of antibodies elicited by T-cell-dependent DMPn-HSA (n = 3, 15, 33) is relatively high (KF):1010-1012 M-1). These KF values increase more than K0 during the immune response. The functional affinity is dependent on the molar KNP: HSA ratio. The mediate coupled DMP15-HSA elicits antibodies with the highest functional affinity. Carps immunized with T-cell-independent DNP-conjugates synthesize antibodies which have similar K0 as the antibodies elicited with DNP-HSA. However, the KF-values are in the range from 107 to 1010 M-1 only. The KF of antibodies raised with DNP-BA are 103-104 fold, those of DNP-S III and DNP-Ficoll elicited are only 4 . 101 to 4,7 . 102 fold higher than their corresponding K0-values. This means that these antibodies are not very effective in binding the multivalent DNP-T4. Specifically purified antibodies have also such low functional affinities. These strong differences in the functional affinity of carp DNP-antibodies elicited by T-cell dependent and independent DNP-conjugates are discussed with regard to stimulation of different B-cell subpopulations.
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PMID:[Regulations of IgM immune response. IV. Effect of the hapten: carrier ratio and the nature of the carrier on the intrinsic and functional affinity of carp DNP-antibodies]. 12 87

As an advanced stage of glycation, glycated human serum albumin (G-HSA; glucose content, 2 mol of 5-hydroxymethylfurfural equivalent/mol of HSA) was incubated at 37 degrees C up to 30 d in 0.2 M phosphate buffer, pH 7.4, with 100 microM Fe3+. G-HSA incubated for 30 d (G-HSA-30(Fe)) was subsequently hydrolyzed at 110 degrees C for 24 h in 6 N HCl. In the hydrolysate, N epsilon-carboxymethyllysine (CML) was identified by cochromatography with synthesized CML on an amino acid analyzer. pI of HSA (4.8) shifted to 4.5 in G-HSA. A more acidic fraction, pI 4.3, appeared in G-HSA-30(Fe). CML content (mol of CML/mol of HSA) of HSA and G-HSA was as follows; 0 in HSA, 0.2 in HSA-30(Fe), 0.4 in G-HSA and 1.5 in G-HSA-30(Fe) pI 4.3. The amino acid compositions also changed in lysine, arginine and tyrosine at the advanced stage of the reaction.
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PMID:Identification of the carboxymethyllysine residue in the advanced stage of glycated human serum albumin. 161 83

The deposition of antigens and immune complexes (IC) in the renal glomerulus is charge-dependent. The demonstration that molecules of net anionic charge, but with discrete positively charged regions, exhibit affinity for the glomerular basement membrane (GBM) extends this concept. Charge hybrid (polar) molecules were constructed by covalently coupling small polycations (lysozyme or linear poly-L-lysine chains with a mean of 17 and 20 residues) to larger polyanions (ovalbumin or human serum albumin (HSA]. Although the products were of overall net anionic charge they still bound to glomerular structures. Immunofluorescence studies performed after i.v. injection of the samples into rats revealed that HSA:poly-L-lysine had the highest affinity. Radioisotopic measurements showed uptake of HSA:poly-L-lysine to be a function of the number of lysine residues; binding of HSA:poly-L-lysine20 was 2.5 times higher than HSA:poly-L-lysine17 (P less than 0.01). Prior injection of a small competing polycation (polyethyleneimine 1200) reduced uptake of HSA:poly-L-lysine by 75%, indicating the charge-based nature of the interaction. HSA:poly-L-lysine20 alone was effectively eliminated from the glomeruli within 72 h. Administration of HSA:poly-L-lysine followed by anti-HSA antibody induced immune complex formation in the capillary wall, giving rise to a granular immunofluorescence pattern and discrete subendothelial and subepithelial deposits. Molecules with polar structure do occur naturally and may contribute to immune complex formation in glomerulonephritis.
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PMID:Surface charge distribution is a determinant of antigen deposition in the renal glomerulus: studies employing 'charge-hybrid' molecules. 174 55

The immunogenicity of captopril (CP), conjugated to heterologous proteins, was investigated in male New Zealand White rabbits by monthly injections of CP-protein conjugates in Freund's Complete Adjuvant. Anti-CP antibody activity was readily detected by immunodiffusion in sera of rabbits immunized with the amide-linked CP-HSA (23:1) conjugate. Hapten inhibition studies revealed that the antigenic determinant contained CP and a lysine residue from the protein carrier. When rabbits were immunized with disulphide-linked CP-S-S-HSA (9:1) and CP-S-S-KLH (160:1) conjugates, anti-CP antibody activity was detected by a sensitive ELISA method, but not by immunodiffusion and radioligand binding assays. The specificity of the serum IgG anti-CP activity after immunization with disulphide-linked CP-S-S-protein conjugates was confirmed since anti-CP activity was inhibited by preincubation of the antisera with CP conjugated to an unrelated protein carrier (CP-S-S-OVA), but not by the corresponding unconjugated protein, nor by penicillamine-S-S-protein conjugates. These results show that disulphide-linked CP-protein conjugates are sufficiently stable to induce humoral (B lymphocyte) anti-hapten responses under the experimental conditions employed. In a separate study, delayed-type skin hypersensitivity reactions to topically applied CP were demonstrated in the guinea pig. The specific and sensitive immunochemical technique (ELISA) described here could be useful in future studies for determining whether or not patients taking CP produce antibodies to the drug.
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PMID:Drug-protein conjugates--IX. Immunogenicity of captopril-protein conjugates. 393 17

To assess the immunological cross-reactivity of the monobactam antibiotic aztreonam (AZ), rabbits were immunized with protein conjugates of benzylpenicillin, cephalothin (CEPH), and AZ. The resulting antibenzylpenicilloyl (BPO) and anti-CEPH rabbit antibodies showed negligible cross-reactivity with AZ conjugated to human serum albumin (AZ-HSA), whereas anti-AZ showed negligible cross-reactivity with BPO-HSA and CEPH-HSA. Unlike benzylpenicillin and CEPH, unconjugated AZ was as effective as AZ conjugated to epsilon aminocaproic acid (AZ-EACA) in inhibiting the binding of homologous antibody. Studies with various analogs of AZ confirmed that immunoglobulin G (IgG) anti-AZ was entirely side-chain specific. The inhibition of the binding of human IgE anti-penicilloyl to BPO-HSA was studied in the presence of AZ-EACA, BPO-formyl lysine, and CEPH-EACA. Whereas CEPH-EACA displayed 3% cross-reactivity with BPO-lysine, AZ-EACA showed little or no cross-reactivity (much less than 0.9%). To assess the immunogenicity of AZ in humans, IgE and IgG antibodies were measured in sera from 36 healthy male volunteers receiving 0.5 or 1 g intravenously or intramuscularly every 8 h for 7 days. None of the subjects had detectable preexisting IgE reactive with AZ or demonstrated an IgE response to antibiotic administration. Four subjects gave evidence for naturally occurring IgG cross-reactive with AZ, but only one subject demonstrated a rise in IgG levels after exposure to AZ. This anti-AZ IgG did not cross-react with BPO or CEPH conjugates of bovine thyroglobulin and was completely side-chain specific. These studies suggest that AZ displays very low immunological cross-reactivity with other beta-lactam antibiotics and may be only weakly immunogenic in humans.
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PMID:Immunology of the monobactam aztreonam. 653 98

Covalently cross-linked immune complexes were prepared with multivalent antigens, obtained by coupling varying numbers of 4-azido-4-nitrophenyl groups (NAP) on human serum albumin as the carrier molecule (NAPn . HSA). In this system the haptenic group served to bind the antigen to the antibody (antibodies to NAP) and to form covalent bonds upon photoactivation. The covalently cross-linked immune complexes contained around 30% of antibodies that were dissociable from complexes by SDS polyacrylamide gel electrophoresis. A comparable portion of antibody-combining sites were accessible to the free hapten (NAP . lysine) in molar excess by equilibrium dialysis. The stable, covalently cross-linked complexes with NAP7.0 . HSA and NAP12.9 . HSA were prepared and separated into complexes with varying degrees of lattice by sequential steps of gel filtration. Ag1Ab1 complexes were obtained with reasonable homogeneity. Other preparations contained successively higher lattices but were not homogeneous. When these complexes were injected into mice, the increasing lattice of complexes resulted in increasingly rapid removal of the complexes from the circulation. The antigen, independent of lattice, also contributed to removal of complexes from circulation. NAP12.9 . HSA alone was removed from circulation faster than NAP7.0 . HSA, and Ag1Ab1 complexes with NAP12.9 . HSA were removed faster than Ag1Ab1 complexes with NAP7.0 . HSA. The studied system adds covalently cross-linked immune complexes with multivalent antigens to the armamentarium of covalently cross-linked complexes that previously were obtained only with bivalent affinity labels.
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PMID:Covalently cross-linked immune complexes prepared with multivalent cross-linking antigens. 729 22

A stable 99mTc-labelled compound that is easy to prepare and that is retained for a long period of time in the blood would constitute an ideal replacement for 99mTc-HSA (limited by its rapid diffusion) and 99mTc-erythrocytes (lengthy and risky in vitro labelling) as tracer agent for ventriculography. We investigated whether 99mTc-labelled polymers would be suitable for this purpose. Four types of poly-L-lysine (PL) (Mw 41,000 to 377,000) were used either in underivatized form labelled at pH 12, or derivatized with a varying number of mercaptoacetyl (MA) substituents by reaction with N-hydroxysuccinimidyl-S-acetylmercaptoacetate followed by deprotection with hydroxylamine and labelling at pH 7.5. A high labelling yield was obtained in all cases. HPLC-purified 99mTc-PLs and 99mTc-MA-PLs were evaluated in mice, with 125I-HSA as an internal biological standard. The retention in the blood at 10 minutes and 60 minutes p.i. was not higher than about 30% for any of the tested compounds versus 84% for 125I-HSA, and was only 10% for the smallest 99mTc-labelled PL and MA-PL. Liver uptake was high for the 99mTc-PLs, whereas the 99mTc-MA-PL's were excreted in significant amounts to the urine. It is concluded that 99mTc-labelled poly-L-lysines or polymercaptoacetyl-poly-L-lysines are not suitable as blood pool tracer agents.
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PMID:Labelling of poly-L-lysine with 99mTc and evaluation as a possible tracer agent for ventriculography. 763 72

The active principles of a monoclonal antibody (791T/36)-human serum albumin-methotrexate (MoAb-HSA-MTX) conjugate have been investigated and identified. This drug-carrier conjugate has previously been shown to be selective for the target cell line, more potent than the 'free' drug, to be internalized into the lysosomes of the cell and to work by a lysosomotropic mechanism. Digestion of MTX-HSA by lysosomal enzymes showed three peaks by HPLC assay. Using authentic standards prepared by solid-phase peptide synthesis, these peaks were identified as 'free' MTX, MTX-Lys (alpha-epsilon) and MTX-Lys (gamma-epsilon). Optimization of the digestion conditions allowed for a maximum total release of MTX-containing material of 5% after 48 h. Of this released material, only 10% was in the form of 'free' MTX. It was shown that increasing the ratio of drug to carrier improved the efficiency of release of drug, and these results were complemented by in vitro cytotoxicity assays. Such a low level of drug release associated with a conjugate which has been shown to be superior, in terms of cytotoxicity, to 'free' drug against the target cell line was an unexpected finding. The consequences of these results are discussed.
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PMID:Studies on the mechanism of action of an MTX-HSA-MoAb conjugate. 769 11


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