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J J Marchalonis

Publications and source records attributed to J J Marchalonis.

At least 181 records · Page 10Linked to original sources
PubMed1977

Lymphocyte-like cells of the tunicate, Pyura stolonifera: binding of lectins, morphological and functional studies.

In vitro investigations were carried out to determine whether lymphocyte-like (small round) cells of the tunicate Pyura stolonifera react to allogeneic cells and mitogens in a manner comparable to that of vertebrate immunocytes. The lymphocyte-like cells possessed receptors for concanavalin A, wheat germ agglutinin and soybean lectin as shown by binding of radioiodinated lectins in scintillation counting and autoradiographic assays. This binding did not induce mitogenesis. Mixtures of cells of P. stolonifera individuals taken from the same or distinct localities did not show enhanced DNA synthesis when assayed at time intervals ranging from 3 to 10 days. The small round cells of this and other tunicates are not completely similar to vertebrate lymphocytes in morphology. Our observations support the concept that these cells are not directly homologous to immunologically competent vertebrate lymphocytes, but may serve as haemopoietic stem cells as proposed by other (Endean, 1954; Freeman, 1970).

Animals↗
PubMed1977

Direct demonstration of murine thymus-dependent cell surface endogenous immunoglobin.

Antisera raised in mammals to murine immunoglobulin (Ig) do not detect surface Ig on thymus-dependent (T) lymphoma cells as assessed by immunofluorescence analysis. In contrast, chicken antibodies, produced against the (Fab)2 fragment of normal mouse IgG and purified by binding to and elution from IgG-Sepharose 4B, give strong indirect fluorescence with murine T cells and cultured T lymphoma cells. The surface Ig caps, is shed, and reappears, indicating that it is of endogenous origin. Nonlymphoid tumor cells of various myeloid types do not bind this reagent, even though they bear avid Fc receptors. The capacity of chicken antibodies to bind to both bone-marrow-dependent and T cell lymphomas was abolished by adsorption with myeloma-derived kappa chains coupled to Sepharose. The kappa antigenic determinant recognized by the chicken antibodies may thus be different from that seen by mammalian antibodies, and the degree of exposure of Ig on the T lymphoma surface might also affect ease of detectability with these reagents. These data provide direct evidence that T lymphocytes and T lymphoma cells express and synthesize a surface Ig containing determinants that at least 'crossreact with bone-marrow-cell-derived kappa chains.

Animals↗
PubMed1977

Immunoglobulin gamma chains of a monotreme mammal, the echidna (Tachyglossus aculeatus): amino acid composition and partial amino acid sequence.

The echidna represents the lowest stage in phylogeny at which molecules clearly homologous to IgG antibodies appear to occur. We provide evidence that a fraction of gamma chains possess an unblocked N terminal sequence comparable to the VHIII sub-group of human gamma chains and that glycine is the C-terminal residue. Statistical comparison of amino acid composition of the component chains with other immunoglobulin heavy chains suggests that echidna gamma chains are more closely related to eutherian gamma chains than to the 7S Ig heavy chains from amphibia or aves. The results are consistent with our view that true gamma-type heavy chains did not appear in evolution until after the mammalian line diverged from the stem reptiles.

Amino Acid Sequence↗
PubMed1977

Structural restriction and similarities of the light chains of antibodies to group B streptococcal carbohydrate produced in a single rabbit.

Comparison of the amino acid compositions, N-terminal amino acids and tryptic peptide maps of two L chains (145 LI and 145 LII) derived from antibodies produced in a single rabbit to group B streptococci indicates a high degree of sequence homology of the two chains. Furthermore, comparison of these data with similar analysis of L chains prepared from pooled antibodies to group B streptococci indicates a high degree of V region restriction in the L chains of antibodies elicited by hyperimmunization with streptococci.

Amino Acids↗
PubMed1977

Molecular properties of T lymphoma immunoglobulin. I. Serological and general physicochemical properties.

Immunoglobulin (Ig) released into the medium by monoclonal continuously cultured murine T lymphoma cells of the lines WEHI-22 and WEHI-7 was isolated by serological precipitation or solid-phase immunoadsorption techniques. The intact immunoglobulin had an electrophoretic mobility on sodium dodecyl-sulphate (SDS) containing polyacrylamide gels comparable to that of IgG (mass 150,000). This mobility was significantly faster than that of '7S' IgM of murine B lymphocyte surfaces. The T lymphoma immunoglobulin consisted of a pair of heavy chains linked by disulphide bonds and light chains non-covalently bound to the heavy chains. The isolated heavy chains migrated slightly faster than the mu chains of MOPC 104E IgM. Some, but not all, antisera directed against mu chains of normal mouse serum IgM bound T lymphoma immunoglobulin apparently via a cross-reaction localized to the Fd fragment. These data indicate that immunoglobulin of T lymphoma cells and, presumably normal T lymphocytes, represents an immunoglobulin isotype which is distinct from those immunoglobulins found on the B cell surface.

Animals↗
PubMed1977

Evidence for common and distinct determinants of colon carcinoembryonic antigen, colon carcinoma antigen-III, and molecules with carcinoembryonic antigen activity isolated from breast and ovarian cancer.

This study was designed to answer the question, do molecules with carcinoembryonic antigen (CEA) activity from colon, breast, and ovarian cancer differ? Extracts of two breast and three ovarian cancers with CEA activity were compared to three colon cancer CEA preparations and to the related antigen, colon carcinoma antigen-III, in terms of lectin- and antiserum-binding properties. With the use of Farr-type radioimmunoassays with the lectins, concanavalin A and wheat germ agglutinin, the iodinated colon CEA and CEA-like preparations from breast and ovarian cancer all showed distinctly different patterns of binding. Specificity of binding was confirmed by inhibition studies with the relevant monosaccharides. Similarly, with antisera prepared against colon CEA, colon carcinoma antigen-III, or breast CEA, it was shown that, although all preparations shared some antigens, unique antigenic determinants were also present on all preparations. These data are consistent with the concept of a series of closely related CEA and CEA-like molecules with distinct characteristics for each tissue source of CEA.

Antibodies, Neoplasm↗
PubMed1976

Effects of dibutyrylcyclic AMP on the in vitro primary response of mouse spleen cells to sheep erythrocytes.

Exogenously added N6, 02'-dibutyryladenosine-3'-5'-cyclic phsophate (DBcAMP) exerted a biphasic effect on the in vitro primary response of mouse spleen cells to sheep erythrocytes (SRBC). High concentrations of DBcAMP were markedly suppressive, whereas lower concentrations brought about significant increases in the peak numbers of antibody-forming cells. The kinetics of the response were not altered by DBcAMP. A direct effect of DBcAMP on bone-marrow derived lymphocytes was suggested because this nucleotide increased the in vitro response of "nude" mouse spleen cells to SRBC. The magnitude of the response, however, was considerably less than that mounted by spleen cells of normal mice. These results show that DBcAMP can have either enhancing or suppressive effects on antibody formation and these effects are dependent upon nucleotide concentration, antigen-dosage and time of assay. The effects of this cyclic nucleotide differed in two major respects from those of the synthetic polyribonucleotide adjuvant, polyadenylic acid-polyuridylic acid (poly A:U) complexes. Thus poly (A:U) decreased the time of peak response in vitro but did not increase the magnitude of the response.

Animals↗
PubMed1976

Plasma membrane of a murine T cell lymphoma: surface labelling, membrane isolation, separation of membrane proteins and distribution of surface label amongst these proteins.

Two established techniques for analysis of plasma membranes, namely, lactoperoxidase catalyzed surface radioiodination of intact cells and bulk membrane isolation following disruption of cells by shear forces, were applied in studies of membrane proteins of continuously cultured cells of the monoclonal T lymphoma line WEHI-22. It was found that macromolecular 125I-iodide incorporated into plasma membrane proteins of intact cells was at least as good a marker for the plasma as was the commonly used enzyme 5'-nucleotidase. T lymphoma plasma membrane proteins were complex when analysed by polyacrylamide gel electrophoresis in sodium dodecylsulphate-containing buffers and more than thirty distinct components were resolved. More than fifteen of the components observed on a mass basis were also labelled with 125I-iodide. Certain bands, however, exhibited a degree of label disproportionate to their staining properties with Coomassie Blue. This was interpreted in terms of their accessibility to the solvent in the intact cells.

Animals↗
PubMed1976

Phylogenetic origins of immune recognition: lymphocyte surface immunoglobulins in the goldfish, Carassius auratus.

Membrane immunoglobulin (Ig) of splenocytes and thymocytes of the goldfish, Carassius auratus, was demonstrated by indirect fluorescent-antibody techniques. Observations on shedding and resynthesis indicated that the thymocyte Ig was endogenously produced. The lymphocyte surface proteins were radioiodinated using the lactoperoxidase-catalyzed reaction, and the labeled Ig molecules were isolated by specific precipitation and analyzed by sodium dodecyl sulfate/polyacrylamide gel electrophoresis. The IgM-like membrane Igs of splenocytes and thymocytes were shown to differ in their ease of solubilization with nonionic detergent, and in the sodium dodecyl sulfate/electrophoretic mobility of their heavy chains. The significance of these observations for the evolution of T-cell recognition is discussed.

Animals↗
PubMed1976

Cell recognition in plants: Determinants of the stigma surface and their pollen interactions.

The interaction between compatible pollen grains and the female stigma of Gladiolus gandavensis has been used as a model system for investigation of cell recognition in plants. The molecular architecture of the receptive stigma surface has been investigated, and determinants binding to both concanavalin A and beta-glucosyl artificial carbohydrate antigen, as well as esterase activity, have been characterized, and conditions for their isolation have been established. The stigma surface, before and after modification, was found to bind (125)I-labeled proteins nonspecifically. Pollen tube penetration of the papillar cuticle is prevented when the receptor sites for concanavalin A are occupied. The concanavalin-A-binding determinants of the stigma surface have been fractionated to reveal several glycoproteins in the molecular weight range 43,000-93,000 and a group of glycolipids of molecular weight approximately 22,000. These results are interpreted in terms of two major recognition events regulating pollination.

Journal Article↗
PubMed1976

Heavy chains of murine splenocyte membrane immunoglobulins: a comparison with the heavy chains of human and toad serum immunoglobulins.

The mobilities of murine splenocyte surface immunoglobulin heavy chains were compared by polyacrylamide gel electrophoresis in SDS-containing buffers, with those of the heavy chains of human EgM, IgG, and IgD, and toad IgY. Human zota-chain showed a mobility only slightly faster than that of human mu-chain, and required double-labeling techniques for unequivocal resolution. The mobility of the slower murine splenocyte surface heavy chain was identical to that of human mu-chain, but that of the second splenocyte heavy chain was significantly faster than that of human zota-chain, and similar to that of the heavy chain of toad IgY. Although the second murine splenocyte heavy chain is clearly distinct from mu-chain, no physicochemical evidence exists which relates it directly to human zota-chain.

Animals↗
PubMed1976

Evolutionary and developmental aspects of T-cell recognition.

Studies relating to the nature of the antigen-specific T-cell receptor are reviewed in the light of present knowledge of phylogenetic and ontogenetic development. It is suggested that this evidence supports the concept that immunoglobulin (Ig) is the T-cell receptor, and that the following conclusions may be tentatively drawn.

Aging↗