bluuebunny/crossref_metadata_2025_split huggingface dataset:
Protease activity as a possible mechanism of migration inhibitory factor
Authors: Havemann K. , Howat M. , Sodomann C. P. , Havemann Karin , Gürger Sigrid 
Published: February 2007

AbstractThe activity of migration inhibitory factor (MIF), present in the supernatants of specifically and nonspecifically stimulated human lymphocyte cultures, can be blocked by antiproteases of animal and plant origin and by diisopropyl fluorophosphate. MIF, partially purified by column chromatography and zone electrophoresis on polyvinylchloride is blocked in the same way. On the other hand, migration inhibition can be effected by some proteases, especially by cobra venom. These findings are discussed in terms of the probable protease nature of MIF.
Hybrid 7 S immunoglobulin molecules formed in vivo by association of heavy and light chains of different parental origin
Authors: Oriol R. , Barbier Yolaine , Biozzi G. 
Published: February 2007

AbstractRabbits were immunized with the purified 7 S immunoglobulins of normal domestic cock (Ga), guinea hen (Nu) and their hybrid, the Numigall (NuGa).The antisera rendered specific for Ga and Nu immunoglobulins by appropriate absorptions were used to study the antigenic structure of the NuGa 7 S immunoglobulins.Nine to twenty percent of the NuGa molecules showed only Ga antigenic determinants, and six to twelve percent only Nu antigenic determinants. More than half of the NuGa immunoglobulins presented both Nu and Ga antigenic determinants on the same molecule.The heavy and light chains of the 7 S immunoglobulins of the three species were isolated and studied with the same rabbit antisera.The isolated chains of the NuGa immunoglobulins showed either the antigenic structure of Nu or Ga. No hybrid chains could be demonstrated.A model of in vivo chain assembly of heavy and light chains from different parental origin is proposed to explain the presence of hybrid molecules in the NuGa 7 S immunoglobulins.
Similarity of cellular recognition structures for histocompatibility antigens and of combining sites of corresponding alloan tibodies
Authors: Ramseier H. , Lindenmann J. 
Published: February 2007

AbstractTheoretical considerations on a possible similarity between recognition structures (RS) on immunocompetent cells and the antigen‐binding sites of alloantibodies aimed at the same target have been tested experimentally in the PAR assay with the aid of antisera directed against recognition structures (anti‐RS sera). It was found that the activity of an alloantiserum could be neutralized specifically by a corresponding anti‐RS serum. Conversely, the activity of an anti‐RS serum could be blocked specifically by a corresponding alloantiserum. The term “aliotype” is proposed for antigenic determinants residing on the combining region of alloantibodies and on corresponding recognition structures of lymphoid cells.
Studies on antigenic competition III. Is there a competitive step in tolerance induction?
Authors: Taussig M. J. 
Published: February 2007

AbstractThe induction of tolerance to mixtures of antigens has been studied in mice. The mixtures used were rabbit Fab′ and rabbit Fab′, a synthetic polypeptide(T,G)‐Pro‐L and rabbit Fab′, and (T,G)‐Pro‐L and rabbit IgG. It was established that these antigens would compete with each other for antibody production if administered in adjuvant. However, in no case was the threshold of tolerance induction of an antigen affected by the simultaneous induction of tolerance to any other antigen in the mixture. Other competitive systems confirmed this result. Thus, there is apparently no competititve step intolerance induction. Moreover, antigenic competition for antibody production did not occur in animals rendered tolerant to the dominant antigen. The relevance of these findings to the mechanisms of competition and tolerance is discussed.
Subclasses of porcine immunoglobulins G. Production of subclass specific antisera with S‐sulfonated gamma chains
Authors: Metzger J.‐J. , Houdayer Monique 
Published: February 2007

AbstractUsing antisera made against porcine S‐sulfonated heavy chains two subclasses of porcine IgG could be distinguished on the basis of antigenic determinants located on the Fc fragment. The antisera prepared against the porcine gamma chains reacted with other mammalian IgG proteins, but not with avian, amphibian or fish immunoglobulins. Antigenic determinants responsible for cross‐reactivity are further localized on the Fc′ fragment of the porcine IgG molecule. Comparable antisera, specific for porcine light chains, did not cross‐react with IgG from any of the other species tested. Porcine IgG and F(ab′)2 fragment reacted with both the anti‐heavy and anti‐light chain sera, while the Fab fragment reacted only with the anti‐light chain sera. Important antigenic determinants are thus located on the light chains and the Fc portion of the heavy chain of the porcine IgG molecule.
Induction of immunity and tolerancein vitroby hapten protein conjugates. II. Carrier independence of the response to dinitrophenylated polymerized flagellin
Authors: Feldmann Marc 
Published: February 2007

AbstractThe response to dinitrophenylated polymeric flagellin (DNP POL)in vitro, unlike that to DNP monomeric flagellin (DNP MON) or erythrocyte antigens does not require the presence of T cells. It was thus proposed that antigens with repeating determinants, like DNP POL, may immunize B cells without the cooperation of the usual helper cells. Since carrier specificity in secondary anti‐hapten responses is based upon the cooperation of carrier‐reactive T cells and hapten‐reactive cells, the requirement for carrier‐reactive cells in the response to “thymus‐independent” DNP POL and “thymus‐dependent” DNP MON was investigated. Using flagellin‐primed spleen, the anti‐DNP response to DNP MON was enhanced, but not that caused by DNP POL. Furthermore, there was no carrier specificity in the anti‐DNP responses with DNP POL, which elicited similar responses in spleen cells primed with various DNP proteins, whereas DNP MON only immunized spleen cells which were primed with that carrier. Carrier‐hapten cooperation has also been demonstrated by the suppressive effect of unconjugated carrier on the anti‐hapten response to carrier hapten conjugates. Neither the induction of tolerance to flagellin, the carrier, nor the presence of free flagellinin vitrosuppressed the anti‐DNP response to DNP POL. In contrast, both these manoeuvres suppressed the anti‐flagellin response to DNP POL, and both the anti‐DNP and anti‐flagellin responses elicited by DNP MON. Thus, by several criteria, there was no cooperation between carrier‐reactive and hapten‐sensitive cells in the genesis of the response to DNP POL.Spleen cell suspensions deprived of their content of phagocytes responded normally to DNP POL. Thus, since T cells, carrier‐reactive cells and phagocytes are not needed for the induction of a response to DNP POL, this antigen immunizes B cells directly. The use of this simple system should facilitate our understanding of the mechanism of binding of antigen molecules to the surface of B cells in the process of immunization.
Antibody response in rats to the synthetic polypeptide (T,G)‐A‐ genetically linked to the major histocompatibility system
Authors: Günther E , Rüde E. , Štark O. 
Published: February 2007

AbstractVarious inbred strains of rats were immunized with the synthetic polypeptide (T,G)‐A–L and showed considerable differences in their antibody response to this polymer. Further investigations using congenic strains, which differ at the major histocompatibility locus (H‐1, Ag‐B), and F1 and F2 hybrids of high and low responding strains demonstrated that the ability to respond to (T, G)‐A–L is under the control of a dominant factor genetically linked to the H‐1 locus.
Cellular heterogeneity in the thymus. I. Electrophoretic analysis of lymphoid cell populations from chickens
Authors: Droege W. , Malchow D. , Strminger J. L. 
Published: February 2007

AbstractMicro‐cell‐electrophoresis has been applied to demonstrate differences and heterogeneities in various lymphocyte populations. The lymphocytes from the blood, spleen, bursa and thymus of young chickens differ significantly in their electrophoretic mobility (EM) pattern. The blood and spleen lymphocytes appear to be homogeneous by this criteria; bursa cells show slight heterogeneity, and thymus lymphocytes contain two clearly distinct subpopulations.One of the two thymocyte subpopulations is absent in neonatally bursectomized and irradiated animals. This bursa‐dependent cellular component in the thymus has about the same EM as bursa cells themselves, which may suggest that these cells are, as such, derived from the bursa. The possible role of the bursa‐dependent subpopulation is discussed. Within the first months of life, there is a dramatic shift from the predominance of the electrophoretically slower population to its virtually complete disappearence and the subsequent dominance of the other cellular component.Bursectomy plus irradiation provided pure preparations of one of the thymus subpopulations. The other subpopulation could be highly enriched by differential centrifugation in chicken plasma. Both subpopulations are thus separately available for direct immunological tests.The reduction of the EM by neuraminidase show that sialic acid is a major charged component in the cell surface of all lymphocyte preparations tested. The data indicate also that the different EM of the two thymocyte subpopulations is not due to different amounts of neuraminidase labile groups on the cell surface. The high EM of blood lymphocytes, on the other hand, is probably to be explained by a high content of neuraminidase‐labile groups, as well as some ribonuclease sensitive material. A substantial reduction of the EM by ribonuclease was observed on blood lymphocytes, but not on lymphocytes from other organs.
Anaphylatoxin formation by contact activation of plasma III. Fixation of two different anaphylatoxin‐forming complexes on zymosan
Authors: Brade V. , Schmidt Gisa , Vogt W. 
Published: February 2007

AbstractDuring incubation of zymosan with human or guinea pig serum, a complex is fixed on the polysaccharide which, after washing, releases anaphylatoxin from C5 when incubated with an anaphylatoxinogen preparation from rat serum containing C3 and C5. In order to form this complex, properdin and an unknown serum factor (UF), as well as high serum concentrations (not less than 1:4), are needed. No anti‐zymosan antibodies need be added. The complexes consume little C2 from serum and are active in anaphylatoxin (AT) liberation in small amounts (3 mg zymosan complex/ml substrate). After spontaneous decay of the AT‐forming activity, regeneration is affected by addition of UF, not by C2.Zymosan‐R3g.p., i.e. guinea pig serum lacking properdin and UF because of pretreatment with zymosan, does not coat fresh zymosan with an active AT‐liberating complex, although it contains C1, C4, and C2. However, it does coat zymosan to which large amounts of rabbit anti‐zymosan antibodies have already been fixed. The resulting complement complex ZAC 142 forms at serum (R3) dilutions of 1:10 also. It effectively releases AT from substrate only when present in high amounts (20 mg/ml substrate); it largely consumes C2 from serum, and it is less active as an AT‐forming system than the zymosan properdin complex. Thus, two different AT‐forming systems can be activated by and fixed to zymosan, both derived from serum factors.No evidence for activation or fixation of the properdin system by sheep red cells was found. Red cells appear to release AT only via the complex of early complement factors. It is probably the special polysaccharide surface which enables zymosan and possibly other (lipo)polysaccharides to fix the properdin system.
The dynamic state of the lymphocyte membrane. Factors affecting the distribution and turnover of surface immunoglobulins
Authors: Loor F. , Forni Luciana , Pernis B. 
Published: February 2007

AbstractThe immunoglobulins which are present on the membrane of B lymphocytes of different species are mobile in the plane of the membrane itself.This mobility results in the formation of spots of immunoglobulins when the cells are treated with divalent antibodies against immunoglobulins; the spots then combine into polar caps.The process of spot formation is not inhibited by different substances that inhibit cell metabolism, but is markedly inhibited in the cold.The formation of caps is followed by the disappearance of immunoglobulins from the cell membrane but, if the cells are not left in contact with the anti‐immunoglobulin antiserum, there is a rapid resynthesis of new membrane immunoglobulins. It appears that the percentage of lymphocytes that resynthesize immunoglobulins is identical to that of cells originally carrying immunoglobulins, but the amount of surface immunoglobulins of each cell is increased after antiserum treatment. Many other membrane antigens behave in a similar way after treatment with the corresponding antisera; the possible role of the mobility of membrane proteins for the immunological functions of lymphocytes is discussed.
Metabolic characteristics of lymphocyte surface immunoglobulins
Authors: Wilson J. D. , Nossal G. J. V. , Lewis Heather 
Published: February 2007

AbstractRabbit anti‐mouse globulin reagents at low concentration were attached to the surface of living mouse lymphocytes in the cold. After appropriate washing, the cells were incubated under tissue culture conditions but without C02 gassing and the rate of disappearance of the antiglobulin from the cell surface was monitored. Two methods were used, namely, direct labeling with 125I‐labeled antiglobulin, and sandwich labeling in which the amount of residual antiglobulin at the surface was measured by assessing the degree of binding of a 1251‐labeled sheep anti‐rabbit globulin reagent. Binding of radioactivity to cells was measured both by scintillation counting of washed cell suspensions and by quantitative radioautography.Elution of polyvalent antiglobulin, anti‐k or anti‐μ sera from spleen cells was surprisingly rapid. There was an initial phase of very fast elution and some 30% of counts were lost within 30 min or so, but control experiments showed that this phase was irrelevant to the main experiments. Subsequently, counts were lost more slowly and a reasonable first approximation to the half‐life of Ig receptors on B cells was 2 h. In contrast, lymphocyte surface H‐2 antigen and the receptors to which anti‐lymphocyte globulins attach were much more stable. A number of control experiments suggested that anti‐Ig reagents were shed from the cell surface by true metabolic turnover of B cell receptors, and not by antigen‐ antibody uncoupling or anti‐receptor‐induced extrusion. It was strongly suggested that some pinocytosis of attached antiglobulin occurred, but that this was not the major source of anti‐receptor loss. Shed receptors were continually regenerated, and the process of shedding was shown to be dependent on lymphocyte metabolic activity.Thymus lymphocyte surface Ig also turned over, but at a rate considerably less than that for spleen cells.A continuous, gentle leakage of Ig from the B lymphocyte surface was deemed to have important theoretical implications. These included a logical source of much natural antibody, increased emphasis on the multi‐hit nature of both immune induction and tolerance induction, a plausible explanation for the necessity of multi‐point binding of antigens to B cells in activation and a rationale for the fact that many adoptive immune responses require active immunization of the host animal.
Responses of athymic (“nude”) mice to sheep red blood cells
Authors: Pantelouris E. M. , Flisch P. A. 
Published: February 2007

Abstract“Nude” (thymusless) mice immunized with sheep red cells gave rise to indirect PFC in numbers (per million spleen cells) that were comparable to those of normal animals for days 2 ‐ 4, but declined sharply thereafter. Hemolysin and hemagglutinin titers follow essentially the pattern of the direct PFC response.About two‐thirds of nude animals also formed some indirect hemolytic plaques which are interpreted as due to 7 S (IgG) globulins rather than to low efficiency 19 S (IgM) globulins.In the secondary response, nude mice failed to exceed their primary performance in any of the four parameters measured: direct PFC, indirect PFC, hemolysin titers and hemagglutinin titers, thus demonstrating the thymus dependence of immunological memory.The initial spurt of immunological reactions by nude animals, followed by premature decline suggest a failure of proliferation or recruitment of immunologically responding cell population in the absence of a thymus.
Cell transfer studies in a genetically controlled immune response
Authors: Chesebro B. W. , Mitchell G. F. , Grumet F. C. , Herzenberg L. A. , McDevitt H. O. , Wegmann T. G. 
Published: February 2007

AbstractFetal liver cells from 14‐17‐day old mouse embryos of inbred strains which are genetic responders (C57BL/ 10) or nonresponders (CBA) to a branched synthetic polypeptide [(T, G)‐A‐L] were injected into reciprocal (nonresponder or responder) strain, lethally irradiated adult mice. These radiation chimeras were then tested for: (a) their ability to respond to (T, G)‐A‐L; (b) the allotype for specific anti‐(T, G)‐A‐L antibody produced; and (c) the degree of tolerance for CBA (nonresponder) histocompatibility antigens of C57BL/10 (responder) cells taken from high responder chimeras.Eleven high responder radiation chimeras had specific anti‐(T, G)‐A‐L antibody, which appeared to be exclusively responder (C57BL/10) allotype. However, since all the high responder chimeras were predominantly C57BL/10 in total serum immunoglobulin allotype and lymphoid cell type, this result is not conclusive.Six high responder chimeras had C57BL/10 spleen cells which were tolerant of CBA (nonresponder) histocompatibility antigens in the Simonsen discriminant spleen assay.
Antibody‐induced redistribution of HL‐A antigens at the cell surface
Authors: Kourilsky F. M. , Silvestre D. , Neauport‐Sautes C. , Loosfelt Y. , Dausset J. 
Published: February 2007

AbstractThe in vitro binding of anti‐HL‐A antibodies to the membrane of human lymphocytes induces important changes in the distribution of HL‐A antigens on the cell surface. Following either direct or indirect immunofluorescence staining at 0 °C, cell‐bound anti‐HL‐A antibodies are dispersed all over the cell surface. When the washed, stained lymphocytes are warmed and incubated at 37 °C, fluorescent antibodies cluster progressively at the cell surface. They form large spots of fluorescence, and sometimes single caps at one pole of the cell, outside which HL‐A antigens are no longer detectable, but other antigens can still be found. Similar findings were made in electron microscopy, following indirect labeling of HL‐A antigens on human lymphocytes, with ferritin or plant virus as the markers.With the indirect immunofluorescence technique, anti‐human thymocyte antibodies and anti‐mouse H‐2 antibodies were found to induce a similar redistribution of the corresponding antigens.The mechanism and the interpretation of this displacement of surface antigens by antibodies are still unclear and are discussed in terms of membrane structure and immunological significance.
Localization of antigenic determinants on bovine encephalitogenic protein Studies in rabbits with the blood leukocyte transformation test
Authors: Bergstrand H. 
Published: February 2007

AbstractBovine encephalitogenic protein and different fragments of it have been used to show that the protein contains at least three antigenic determinants capable of stimulating the transformation of peripheral blood leukocytes from sensitized rabbits. The determinants were tentatively localized on regions 1 ‐ 43, 44 ‐ 116 and 117 ‐ 170, respectively. There was no evidence that the tryptophan‐containing region carries an antigenic determinant when tested with leukocyte transformation in rabbits.
Recognition of conjugated and native peptide determinants. II. Enhancement of antibodies with sequential specificity in anti‐TMV sera by preimmunization with conjugated peptide antigens
Authors: Anderer F. A. , Ströbel G. 
Published: February 2007

AbstractRabbits which were preimmunized with the C‐terminal peptides of TMV protein conjugated to cross‐linked bovine serum albumin were stimulated with native TMV. All animals responded with a striking titer increase of antibodies with sequential specificity versus the C‐terminal peptides of TMV compared with animals which had not been preimmunized with the conjugated peptide antigens. The same degree of antibody enhancement with sequential specificity was obtained when the animals were stimulated with TMV for a second time after an interval of 255 days. The class distribution of 19 S and 7 S antibodies with sequential, as well as with conformational specificity, versus TMV was determined.
Antibody response to bacteriophage ϕX 174 in vitro: Demonstration of immunological memory in terms of IgM and IgG responses
Authors: Tao T. W. 
Published: February 2007

AbstractThe initiation of a primary‐type antibody response to bacteriophage ϕX 174 has been studied in organ cultures of lymph nodes from normal rabbits. Lymph nodes are also removed for culture at various times following a primary injection of ϕX in the rabbits and their responsiveness to a second anti‐genic stimulus investigated. All the cultures are maintained for 2 to 4 weeks and the antibody responses followed throughout. The following points are shown.
The ability of non‐primed lymph node fragments to initiate a primary type response in responding to ϕX stimulation in vitro declines rapidly during the first 2 ‐ 3 days and is lost after 3 days of culture.
An apparent failure to develop a primary IgG response is shown in cultures of non‐immunized lymph nodes even when the antigen was given for 1 to 6 days continuously or given twice, once on day 0 to 1 and another time on day 2, 3, 4, or 5.
Following antigenic stimulation in vitro, cultures of lymph nodes from rabbits immunized one (to two) days previously produce an antibody response of primarly IgM antibodies with a geometric mean significantly smaller than that produced by non‐primed lymph node cultures.
Cultures of primed lymph nodes without a secondary antigenic stimulation in vitro produce antibodies only of the type present in the animal at the time of the tissue removal.
Cultures of lymph nodes from rabbits immunized more than 4 days previously exhibit IgM and IgG memories. The secondary response initiated in vitro exhibits predominantly IgM memory when cultures are of nodes primed in vivo 4 days previously, but exhibits primarily IgG memory when cultures are of nodes primed in vivo 14 days previously. Intermediate proportions of IgM and IgG are seen at intermediate time intervals.
The ability of primed lymph nodes to show the phenomenon of memory appears to be positively correlated in time with the ability to develop IgG antibodies.
IgM memory is transient in the sense that it is exhibited only in lymph nodes primed in vivo less than 2 weeks previously, whereas IgG memory lasts as long as the life of the animal.