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J J Marchalonis

Publications and source records attributed to J J Marchalonis.

At least 127 records · Page 7Linked to original sources
PubMed1984

Invertebrate recognition protein cross-reacts with an immunoglobulin idiotype.

To estimate the minimal structural requirements for cross-reaction of idiotypic determinants, we determined the capacity of monoclonal antibodies specific for the idiotype of the phosphorylcholine (PC)-binding myeloma protein TEPC-15 for cross-reactivities with the PC-binding, acute-phase protein C-reactive protein (CRP) and the hemagglutinin from the horseshoe crab Limulus polyphemus (limulin), which binds sialic acid and PC. Certain monoclonal antibodies (MAb) to the TEPC-15 idiotype showed strong cross-reactions with CRP and limulin when tested by enzyme-linked immunoadsorbent assays. The specificity of the cross-reactivities was confirmed by testing the binding of the reactive anti-TEPC-15 MAb to both CRP and limulin in the presence of p-nitrophenylphosphorylcholine (pNPPC), N-acetylneuraminic acid, and bovine submaxillary mucin. The binding of the MAb to both CRP and limulin was strongly decreased by pNPPC, partially decreased by free PC, and not affected by N-acetylneuraminic acid or bovine submaxillary mucin. Neither CRP nor limulin showed significant overall sequence homology to vertebrate immunoglobulins. However, CRP, limulin, and TEPC-15 variable region heavy chain (VH) shared short stretches of homology (8-10 amino acids) that mapped to a stretch comprised of the second complementarity determining region and third framework region of the TEPC-15 VH. These results might reflect either evolutionary convergence forced upon molecules of diverse evolutionary histories because of steric requirements of binding the same ligand, or a conservation of primitive combining site gene segments in evolution.

Animals↗
PubMed1984

Molecular analysis of the lymphocyte membrane.

Methods for the molecular analysis of lymphocyte membranes are reviewed briefly, and wherever possible presented in a manner relevant to comparative studies. The specific areas reviewed include the bulk isolation of lymphocyte membranes, the use of radioisotopes to covalently label lymphocyte membrane molecules, the use of lectins to characterize membrane glycoconjugates, and our current understanding of lymphocyte membrane immunoglobulins.

Animals↗
PubMed1984

Identification of amino acid residues implicated in the cross-reaction between immunoglobulin VH and a T cell receptor molecule.

The problem of the relationship between the immunoglobulin-related T cell receptor (IgT) and classical immunoglobulin heavy chain variable regions (VH) was approached by determining the capacity of a xenoantiserum made against the immune affinity purified product of a permanent in vitro T cell line of mature, amplifier phenotype to react with human and murine monoclonal immunoglobulins with completely sequenced VH regions. Most of the amino acid residues identified as critical for the observed serological cross-reaction were localized within the disulfide-bonded loop and all of these occur on the surface of the 3-dimensional structure of the VH molecule. The most strongly correlated residues were restricted to the second complementarity determining region and the third framework region. This suggests that IgT need not contain complete VH regions, but that the serological cross-reaction might result from the insertion of 'minigenes' into a non-immunoglobulin framework or from short stretches of shared sequence between VH and the products of separate VT gene cluster.

Amino Acid Sequence↗
PubMed1983

Rapid molecular weight estimation and separation of selected immunoglobulin chains by high speed gel filtration.

Rapid and reliable molecular weight estimations of reduced and alkylated immunoglobulin heavy or light chains were performed by high speed gel filtration in 6 M guanidinium chloride using a short (30 cm X 7.5 mm) TSK 3000 SW type column. Molecular weight estimations based on Kav values of eluted polypeptides and glycopolypeptides were generally unaffected by protein bound carbohydrate. Rapid separation of immunoglobulin H and L chains was also achieved during high speed gel filtration.

Animals↗
PubMed1983

Some T-cell leukemia lines express surface markers related to a restricted set of human VH determinants.

Serological studies were carried out to obtain information regarding the relationship of the VH-related determinants expressed by certain permanent in vitro T-cell leukemia lines and corresponding determinants expressed by characterized human serum immunoglobulins. A panel of conventional (goat and rabbit) antisera, produced against various Fab-related fragments of monoclonal human Waldenstrom macroglobulins and polyclonal IgG molecules, bound to certain in vitro T-cell leukemia lines, notably, 70-N2, MT-1, YT4E, and HUT78, as shown by microhemagglutination. Inhibition studies using characterized myeloma proteins to inhibit this agglutination indicated the expression of a restricted VH-related determinant by these T-cell lines. Parallel studies performed using conventional (rabbit) and murine monoclonal/hybridoma antibodies produced against the isolated 68,000-Da VH-related product synthesized by the 70-N2 line showed that the determinant expressed by this molecule was restricted in expression, comprising 2-3% of the normal, polyclonal human Fab pool, and that the determinants found on the other positive T-cell leukemias were cross-reactive rather than identical. The inhibition studies suggest that the determinant resides between residue 22 and the end of the VH region. These results further define the antigenic nature of the VH-related marker found on the surfaces of certain normal and neoplastic T-cell lines.

Animals↗
PubMed1983

Antigenic and structural characteristics of an immunoglobulin-related peptide purified from marmoset T-lymphoma cells.

A 7800 Mr peptide, apparently derived from a 70,000 Mr immunoglobulin-related protein synthesized by a marmoset T-lymphoma cell line, bears immunoglobulin-related determinants apparently contained in a disulfide-bonded loop comparable to that of the VH fragment of classical H chain. A membrane-enriched, crude particulate fraction was prepared from marmoset T-lymphoma cells, and peptides generated by papain digestion of the particulate fraction were selectively purified by affinity chromatography using IgG purified from serum of a goat immunized with the Fab fragment of a human Waldenstrom macroglobulin. The smallest of the affinity-purified peptides was particularly reactive with unfractionated goat anti Fab (G alpha Fab) serum, purified IgG from G alpha Fab serum, and with antibodies affinity purified from G alpha Fab serum using Waldenstrom macroglobulins. Partial specificity of G alpha Fab antibodies was determined by competition radioimmunoassay and radioimmunoprecipitation assays. High-performance reverse-phase liquid chromatography was used for final purification of the smallest peptide which retained its reactivity with G alpha Fab serum and affinity-purified G alpha Fab antibodies. The apparent molecular weight of the peptide, determined by gel filtration in 6 M guanidine, was estimated at 3900 in its native state but increased to 7800 after reduction and alkylation, indicating a role for a disulfide bond in the tertiary structure of the peptide. The amino acid composition of the peptide was presented, and its possible relationship to immunoglobulin-like T-cell surface proteins was discussed.

Amino Acids↗
PubMed1983

Serological characterization of humoral lectins from the freshwater prawn Macrobrachium rosenbergii.

We have detected and partially characterized multiple lectins present in the serum of the freshwater prawn Macrobrachium rosenbergii. Since agglutination of erythrocytes (RBC) is not abolished by treatment with Vibrio cholerae neuraminidase (VCN), Macrobrachium shows an agglutination pattern different from that of other sialic acid-specific lectins such as Limulus polyphemus lectin. However, after absorption with primate and bird VCN-treated RBC, Macrobrachium serum exhibits high titers with untreated and pronase-treated RBC and no agglutination of VCN-treated RBC, suggesting a typical sialic acid specific lectin agglutination profile. Hemagglutination-inhibition tests indicate that sialic acid containing compounds are the best inhibitors for Macrobrachium lectins. Subterminal sugars and type of linkage are probably important for the lectin binding since bovine submaxillary mucin (containing mainly terminal NANA-alpha-2 6-GalNAc-) is a better inhibitor than fetuin (containing mainly terminal NANA-alpha-2 leads to 3-Gal-) and colominic acid (-NANA-alpha-2 leads to 8-NANA-) is a weak inhibitor.

Animals↗
PubMed1983

Evidence for the existence of a diverse family of immunoglobulin-related recognition molecules.

All classes of molecule postulated to play a role in recognition or to have some structural homology to immunoglobulins were compared by the S delta Q index of differences in amino acid composition. The results suggest that there is a wide family of immunoglobulin-related molecules that includes vertebrate immunoglobulins, T cell receptors, MHC products, C-reactive proteins, and (some) invertebrate lectins.

Amino Acid Sequence↗
PubMed1983

Xenoantisera against a murine T cell tumor product cross-react with immunoglobulin Fab determinants.

Some murine monoclonal T lymphoma cells express a surface component that reacts with chicken antisera produced against the Fab fragment of normal mouse IgG. In the present study, we use a solid phase immunoadsorbent consisting of affinity-purified chicken anti-Fab coupled to Sepharose to isolate a product produced by the in vitro T cell line, WEHI-7.1. The affinity-purified T cell surface molecule (IgT) migrated on SDS-PAGE as a single band of approximately 65,000 daltons. The object of these studies was to produce xenoantisera against the purified T cell product cross-reactive with Ig determinants and to characterize the antisera. Rabbits immunized with this purified molecule produced antibodies that reacted with Fab fragments of polyclonal mouse IgG and with the myeloma proteins MOPC-104E and MOPC-41, as detected by enzyme-linked immunosorbent assay (ELISA). This binding was eliminated by adsorption of the antisera with normal polyclonal IgG; however, adsorption with fetuin did not significantly affect the reactivity of the antisera. Radioimmune precipitation assays revealed that the rabbit anti-IgT bound to normal murine spleen and thymus cells; this reactivity was abrogated by adsorption with insolubilized polyclonal IgG. Competition radioimmunoassays demonstrated that detergent extracts of the thymus and the spleen contained material that inhibited the precipitation of MOPC-41; nonlymphoid cells lacked such material. The rabbit anti-IgT serum blocked the binding of antigen by normal T cells; adsorption of the antiserum with polyclonal IgG-Sepharose abrogated this blocking capacity. A solid phase immunoadsorbent prepared from the IgG fraction of the rabbit anti-IgT isolated a single component from formic acid-solubilized mouse thymus. This molecule had an approximate mass of 65,000 to 70,000 daltons. The anti-IgT serum isolated surface IgM and IgD from lactoperoxidase-catalyzed radioiodinated B cells. The anti-IgT serum detected IgM and IgG in mouse serum with the use of immunoelectrophoresis. The anti-IgT immunoadsorbent isolated several components from normal mouse serum, that, when analyzed by SDS-PAGE under reducing conditions, revealed bands corresponding to mu-, gamma-, and light chains as well as components that migrated between mu- and gamma-chains, and another component with an approximate mass of 45,000 daltons. Our results with antibodies to a purified T cell product indicate that a surface component of normal T cells and certain monoclonal T cell tumor lines is serologically related to the Fab fragment of serum Ig and is implicated in the binding of antigen.

Animals↗
PubMed1982

Insulin binding to cultured B- and T-lymphocytes.

Insulin receptors have been demonstrated on activated but not resting T-lymphocytes. We compared insulin binding to several T- and B-cell tissue culture lines transformed by either radiation or lymphotrophic Herpes virus. Two T-cell lines derived from mouse lymphomas, one T-cell derived from the cotton top marmoset and one mouse B-cell line bound, at most, 3% of a tracer dose of [125I]insulin. In contrast, positive B-cell line (1605 L) derived from a leukemic cotton top marmoset, bound 40% of tracer [125I]insulin. The binding was of high affinity (1.9 nM-1), displayed analogue specificity characteristic of the insulin receptor and receptor number per cell was 16,600. The data show that a transformed B-lymphocyte binds substantial levels of insulin. The magnitude of such expression might be related to the fact that this B-cell line also expresses Epstein-Barr virus.

Animals↗
PubMed1982

Antigenic polypeptide fragments of a receptor related to the Fab fragment of human immunoglobulin from thymus-derived lymphocytes.

Certain thymus-derived lymphocytes of man and other primates express surface components related to the variable region of immunoglobulin heavy chains but lack constant region determinants defining any known immunoglobulin class. To obtain structural information on this molecule that can be used for comparison with known immunoglobulins and other surface molecules, we isolated the T cell-derived molecule by affinity chromatography using an antiserum raised against the monomeric Fab fragment of a human Waldenström macroglobulin and subjected the isolated molecule to either proteolysis using enzymes or cleavage with cyanogen bromide, followed by isolation of polypeptides which bore the Fab- or heavy chain variable region (VH)-related antigenic markers. The intact T cell molecule had an apparent mass of 68,000 daltons and no evidence was found for covalent or noncovalent association with polypeptides resembling light chains in apparent mass. The pattern of fragments obtained by cleavage of the T cell heavy chain suggests that the molecule is comprised of domains of approximate mass 12,000 daltons. Isolation of fragments from the digests that bear Fab-related serological markers shows that the molecule can be degraded into fragments resembling the Fd and VH of standard immunoglobulin heavy chains. A procedure was developed enabling the isolation of milligram quantities of VH-related T cell products. These results support the concept of a sharing of combining site determinants between T cell receptors and immunoglobulin heavy chains and show a general formal similarity between the two classes of molecules, even though they lack shared constant region determinants. The susceptibility of the T cell molecule to be cleaved into discrete antigenic fragments by controlled proteolysis might help to explain the plethora of sizes observed for antigen-specific T cell factors.

Animals↗
PubMed1982

Surface markers of primate B and T lymphoid cell lines identified by antibodies to human and simian lymphocyte antigens.

Simian B and T lymphoid cell lines were shown to maintain surface markers found on mature lymphocytes in vivo. The T lymphoid cell lines expressed Ia-like antigens on their surfaces, further suggesting that they represent mature, activated T cells. These Ia antigens show a structural similarity to Ia on human cells although some diversity exists. The Ia antigen expressed on T lymphoid cell lines was shown to be very similar to those on B lymphoid cell lines. Owl monkey and marmoset T lymphoid cell lines were also shown to express a VH immunoglobulin-related determinant, a marker which is thought to be associated with T cell antigen receptor. Owl monkey and marmoset T cell lines express a surface antigen which identifies the sheep erythrocyte receptor on human T cells and some of these lines express an antigen found on human helper T cells. It is noteworthy that substantial conservation of surface components has occurred within primate evolution such that monoclonal antibodies to human Ia, OKT-11a and Leu 3a markers can be used to type lymphocytes of lower primates.

Animals↗