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T Peters

Publications and source records attributed to T Peters.

At least 253 records · Page 14Linked to original sources

Immune recognition of serum albumin--XIV. Cross-reactivity by T-lymphocyte proliferation of subdomains 3, 6 and 9 of bovine serum albumin.

Recently, we have shown that, with rabbit antibodies against BSA, the BSA fragments 115-184, 307-285 and 505-582 (essentially corresponding to subdomains 3, 6 and 9 of BSA) exhibit a cross-reaction which increases remarkably with the time antisera are obtained after the initial immunization. In the present report, we have examined whether this cross-reaction at the B-cell level takes place also at the T-cell level. Optimum conditions for T-cell proliferation to BSA and the three fragments were determined in terms of priming dose, challenging dose, time lymph nodes are obtained after immunization and finally duration of culture. Several strains of mice representing independent haplotypes and recombinant strains were examined for their responsiveness to BSA by T-lymphocyte proliferation, performed in the respective preimmune sera of the same mice. This afforded the identification of high- and low-responder strains to BSA. It was determined that the immune response to BSA is controlled by genes in the I-A subregion of the H-2 gene complex with some slight non-H-2 influences. In order to avoid the possibility of genetic exclusion of response to a given antigenic site and to improve the change of total site recognition, two high-responder strains (B10.M and B10.G) were crossed. Antibodies raised in (B10.M X B10.G)F1 mice recognized subdomains 3, 6 and 9 and these were found to be cross-reactive. Specific 125I-labelled antibodies isolated on a given subdomain-adsorbent were bound very well by adsorbents of the other two subdomains. T-cells from the F1 mice that had been primed with subdomain 3 responded to subdomain 3 and were also high responders to subdomain 6 and intermediate responders to subdomain 9. After priming with subdomain 6, the T-cells responded equally as well to subdomains 3 or 6 and slightly to subdomain 9. Finally, priming with subdomain 9, gave T-cells that responded to subdomain 9 and also gave high responses to subdomains 3 or 6. It was concluded that the cross-reactions originally observed at the B-cell level also take place at the T-cell level.

Animals↗

Antibody production and antigenic specific suppression to bovine serum albumin in uremic rats.

Antibody response and antigen specific suppression to bovine serum albumin (BSA) in uremic rats have been investigated. Primary immune response was found to be significantly reduced independent of the route of administration or adjuvant while secondary response was affected only in animals in which a weak adjuvant such as Al(OH)3 was used. Antigen specific suppression of uremic rats was achieved by intravenous pretreatment with BSA or a C terminal fragment (505-582) of BSA. Secondary response in sham operated controls was suppressed by BSA but not by the fragment. There was about five-fold greater retention of the fragments in the uremic rats than in sham-operated controls at a 6 hr or later after i.v. administration.

Animals↗

A candidate reference method for determination of total protein in serum. I. Development and validation.

We developed a candidate Reference Method for measuring total serum protein by use of the biuret reaction. The method involves a previously described biuret reagent (Clin. Chem. 21: 1159, 1975) and Standard Reference Material (SRM) 927 bovine albumin (National Bureau of Standards) as the standard. At 25 degrees C, color development for 30 or 60 min provides identical serum protein values. Glucose (up to 10 g/L) and bilirubin (up to 300 mg/L) do not interfere. Hemoglobin, at 3 g/L, increases apparent serum protein by 0.4 g/L. The presence of dextran in serum causes easily detected turbidity, but this interference can be eliminated by centrifuging the reaction mixture. Therapeutic concentrations of ampicillin, carbenicillin, penicillin, oxacillin, nafcillin, chloramphenicol, cephalothin, and methicillin in blood do not interfere, nor do triglycerides up to 10 g/L. Within-run and day-to-day standard deviations of the method are 0.1 and 0.4 g/L, respectively.

Bilirubin↗

A candidate reference method for determination of total protein in serum. II. Test for transferability.

The transferability of the candidate Reference Method for total serum protein was tested in eight laboratories in the United States and Europe. National Bureau of Standards SRM 927 (bovine serum albumin) was used in each analytical run as the calibration standard. The mean absorptivity value obtained for this material was 0.2983 L g-1 cm-1. Four serum pools prepared at the Centers for Disease Control were analyzed on each of 15 days. Within-run variation of the protein values (expressed as CV) in the eight laboratories ranged from 0.1 to 2.5% and day-to-day (total) variation in six of the laboratories ranged from 0.4 to 1%.

Biuret Reaction↗

Sequence of residues 400--403 of bovine serum albumin.

A large tryptic peptide of bovine serum albumin (residues 377--582) was subjected to 32 cycles of Edman degradation to determine the sequence of the last remaining unknown segment of this protein. Residues 400--403 were identified as gly-Phe-Gln-Asn. Amide assignments were also made at positions 388 (glutamine), 389 (asparagine), 391 (aspartic acid) and 392 (glutamine).

Amino Acid Sequence↗

Ligand-binding properties of proalbumin Christchurch.

Proalbumin Christchurch, a circulating variant of human serum albumin, is secreted from the liver without cleavage of the hexapeptide situated at the N-terminal end of the peptide chain of proalbumin. We compared ligand-binding properties of proalbumin Christchurch and of normal albumin A from the same individual in order to test the effect of the presence of the hexapeptide. The two albumin forms exhibited similar affinities for palmitate, bilirubin, 8-anilinonaphthalene-1-sulphonate and Bromocresol Green. The patterns of endogenous fatty acids bound to the two forms of albumin were slightly different, although the differences were probably not of physiological significance. From these studies it would appear that the propeptide of proalbumin does not alter the protein conformation in such a way as to alter binding sites for organic anions.

Anilino Naphthalenesulfonates↗

High resolution computed tomography in cervical syringomyelia.

Thirty-two cases of documented cervical syringomyelia, 13 of which were already surgically proven, were explored by high resolution computed tomography (CT). A central cavitation was demonstrated in all cases. High resolution CT appears to be more reliable than myelography and should be the examination of choice in cervical syringomyelia.

Cervical Vertebrae↗

Studies on the allergenic significance and structure of rat serum albumin.

This study evaluated the capacity of rat serum albumin and of its proteolytic fragments to activate human basophils for IgE-mediated histamine release. The leukocytes from 8 out of 33 patients allergic to rats released histamine with rat serum albumin. Two proteolytic fragments of rat serum albumin, each constituting half of the molecule, were used to study the IgE-reactive antigenic sites. These fragments released histamine with the cells of some of the donors, thus demonstrating the presence of at least 2 antigenic determinants on each fragment for a total minimum of 4 sites on the intact rat serum albumin molecule. Most of the allergenic activity, however, was not recovered in the 2 fragments (total recovery mean = 6.4%, range between 0.1 and 31%). This loss could be due to cleavage of the rat albumin molecule in the middle of the third domain with loss of antigenic sites and/or due to minor conformational changes in the fragments as compared with the intact molecule. There was up to a 500-fold difference in the percent of activity recovered in the fragments when tested on cells from different patients. Therefore, there is no single immunodominant site on the molecule equally important for all patients. The cells of all 8 patients also reacted with mouse serum albumin but only 2 with bovine serum albumin. At least 1 determinant on mouse and rat serum albumin is cross-reactive with IgE.

Allergens↗