bluuebunny/crossref_metadata_2025_split huggingface dataset:
Macrophage cytotoxicity factor. A product of in vitro sensitized thymus‐dependent cells
Authors: Lohmann‐Matthes Marie‐Luise , Ziegler F. G. , Fischer H. 
Published: February 2007

AbstractPeritoneal mouse macrophages are rendered specifically cytotoxic to allogeneic target cells by a cell‐free filtered supernatant from in vivo sensitized spleen cells. Pretreatment of sensitized spleen cells with anti‐θ serum and complement completely abolishes secretion of the supernatant factor. The factor can also be induced by in vitro sensitization of mouse spleen cells to alloantigens. Furthermore, a cortisone‐resistant population of pure thymocytes can be sensitized in vitro and induced to liberate the factor. The macrophage cytotoxicity factor is only effective if bound to macrophages and can be transferred to iso‐ and allogeneic macrophages without loss of activity.
The occurrence of spontaneous rosette‐forming cells in the chicken bursa of Fabricius and spleen
Authors: Bäck R. , Alm G. V. 
Published: February 2007

AbstractThe bursa of Fabricius of non‐immunized chickens contained a significant number of cells forming rosettes (RFC) with sheep red blood cells. A considerably smaller number was found in the spleen. Spontaneous RFC may develop in the bursa and emigrate to peripheral lymphoid tissue.
Allotype‐specific anti‐autoantibody activity in tetraparental NZB mice
Authors: Barnes R. D. , Tuffrey Maureen 
Published: February 2007

AbstractEvidence has favored graft‐versus‐host activity in hitherto assumed tolerant tetraparental NZB ↔ CFW chimeras. The events in this situation appear to be twofold. A primary NZB autoantibody occurs and is followed by secondary CFW allotype anti‐NZB autoantibody activity. Adherence and phagocytosis of Combs'‐coated red cells by primitive lympho‐monocytoid cells in these chimeras has been considered secondary and to reflect this anti‐autoantibody activity. Furthermore, phagocytosis of plasma cells suggest that this receptor determinant reaction might also be responsible for the “normal” elimination of aberrant autoimmune clones.
Characterization of thymus‐derived and bone marrow‐derived rosette‐forming lymphocytes
Authors: Elliott B. E. , Haskill J. S. 
Published: February 2007

AbstractAn improved technique has been developed to accurately quantitate lymphoid rosette‐forming cells (RFC) and to assess the morphology and antigen‐binding ability of each RFC. Two essential features were involved. First, rosettes were fixed with glutaraldehyde (a concentration of 0.6 % minimized the formation of artefacts). This fixation prevented dissociation of rosettes; RFC of weak antigen‐binding ability could therefore consistently be preserved. Second, rosette preparations were stained, thus permitting morphological classification of RFC and the elimination of false rosettes. The antigen‐binding ability of each RFC was determined by the number of sheep red blood cells (SRBC) bound. By this technique, thymus‐derived (T) RFC were found to bind fewer erythrocytes than bone marrow‐derived (B) RFC. Pretreatment of the SRBC with neuraminidase increased the SRBC‐binding ability of B RFC, thus making the latter readily distinguishable from T RFC. Functionally different subpopulations of T and B RFC were suggested.
Immunodeviation by passive antibody, an expression of selective immunodepression. I. Action of guinea pig IgG1 and IgG2 anti‐hapten antibodies
Authors: Vuagnat P. , Neveu Thérèse , Voisin G. A. 
Published: February 2007

AbstractThe effect of passively administered anti‐2,4‐dinitrophenyl (DNP) IgG1 and IgG2 antibodies on their own production has been studied.Guinea pigs were immunized with immune complexes emulsified in complete Freund's adjuvant. These complexes were made at 4 times equivalence with IgG1 and/or IgG2 anti‐DNP antibodies having the same affinity. Humoral IgG1 and IgG2 anti‐DNP antibody contents were assayed at weekly intervals, and 4 and 10 days after a booster injection of antigen in saline given on the 12th week.Active anti‐DNP IgG2 antibody production is strongly inhibited by passive IgG2, IgG1 and F(ab')2 antibody fragments.Active anti‐DNP IgG1 antibody production of the same animals is inhibited by passive IgG2 and F(ab')2, to an extent similar to active IgG2 antibody inhibition, but the response after boosting is normal. On the other hand, passive IgG1 antibodies lead to a delayed enhanced active IgG1 antibody response.The effect of a 1 : 1 mixture of both passive antibody classes is intermediate to what is observed with either class alone.These differential effects according to the class (i.e. the Fc fragment) of the passive antibodies used show the importance of immune complexes in not only the quantitative, but also the qualitative, regulation of the immune response.
Synthesis of DNA by the spleens of germ‐free mice during the primary response to sheep red cells
Authors: Harris G. , Pelc S. R. , Blackmore D. K. 
Published: February 2007

AbstractThe mitotic activity of the spleens of non‐immunized germ‐free (GF) mice was less than in similar specific pathogen‐free (SPF) animals. No evidence of germinal center activity was noted in these GF mouse spleens before challenge with sheep erythrocytes (SRC). These centers only began to develop 4 days after immunization and were not fully developed before 8 days. In control SPF mice, the spleens showed very few germinal centers which were small in size, but they showed the same pattern of evolution as in similarly immunized GF mice.The changes in the red pulp, characterized by the development of clusters of nuclei labeled with [3H]thymidine, followed closely the development of plaqueforming cells (PFC). The numbers of direct PFC reached the same peak level in GF and SPF mice on day 4 of the response to SRC, but were not so well sustained in the former animals after this time. Indirect PFC were much lower in the spleens of GF mice than in SPF animals.The pattern and degree of increase of DNA synthesis in the spleen of GF and SPF mice following immunization with SRC differed from and was less than that of mice reared in less clean conditions. Increased DNA synthesis occurred very soon after injection of SRC (6 to 24 h) and the increase was sustained for 4 days without further significant rise and then declined.Autoradiographs of the spleen of immunized GF mice given [3H]thymidine showed that the first increase of labeled nuclei in the white pulp occurred around the central arterioles as early as 6 h after SRC. This was followed by increased labeling in the mantle layer of the white pulp and the characteristic pattern of germinal center labeling developed after 4 days. Increased labeling of nuclei developed in the red pulp as early as in the white pulp, while the subcapsular and trabecular areas showed high labeling indices even in the spleens of non‐immunized controls.The ratio of labeling index/mitotic index which is governed by the respective durations of DNA synthesis and mitosis in those cells in division cycle, varied between 10 and 280 in different areas of the spleen. This indicated a vast excess of cells synthesising DNA in relation to the numbers of dividing cells actually present in the spleens of these mice.
Direct cell contact is required in the syngeneic mixed lymphocyte reaction
Authors: Von Boehmer H. 
Published: February 2007

AbstractA positive syngeneic mixed lymphocyte reaction can be observed by culturing neonatal thymus cells with syngeneic Mitomycin C‐treated spleen cells. Evidence that direct cell contact between the reacting thymus cells and the stimulating spleen cells is required was obtained by the following experiments. Supernatants from spleen cells prepared after different times of culture failed completely to stimulate syngeneic thymus cells. Stimulation was not transmitted in a double chamber system where thymus cells and spleen cells were separated by a nucleopore membrane (pore size 0.22 μ).Fetal calf serum was not required in the culture medium to obtain a positive syngeneic and allogeneic mixed lymphocyte reaction, indicating that foreign protein does not influence the reaction.
The appearance of migration inhibition factor and a mitogen in lymph draining tuberculin reactions
Authors: Hay J. B. , Lachmann P. J. , Trnka Z. 
Published: February 2007

AbstractThe tuberculin reaction in the skin of sheep was accompanied by greatly increased traffic of mononuclear cells through both the lesion and through regional lymph nodes, as well as the appearance of basophilic cells in the lymph. Changes in vascular permeability were also evident and two, apparently distinct, biologically active materials appeared in the lymph plasma. The first of these materials inhibited the migration of guinea pig macrophages in a conventional migration inhibition factor (MIF) test. This material was evident within a few hours; the strongest activity appeared at about 24 h. Normal lymph and serum or lymph and serum from BCG‐sensitive sheep did not contain this material in detectable amounts. The second material that appeared in the lymph increased the DNA synthesis of normal lymphocyte cultures.
Influence of antigenic stimulation on lymphoid cell traffic in the chicken
Authors: Bäck R. , Linna T. J. 
Published: February 2007

AbstractThe influence of one intravenous injection of human serum albumin (HSA) on the pattern of cell migration from the bursa of Fabricius was studied in six‐week old chickens. The bursa was labeled in situ with ['Hlthymidine 24 h after either HSA o r saline administration. Forty‐eight hours following local labeling of the bursa, the chickens were killed and the transport of label to other lymphoid organs studied with a radiochemical method, based on measurements of tritium in DNA of the different organs, and with autoradiography. The radiochemical method revealed a significantly increased proportion of bursa‐derived label in the spleen of the immunized chickens. This was associated with an increased number of heavily labeled bursa‐derived cells in the autoradiograms from the same organ. The majority of the bursa emigrant cells in the spleen were localized in the red pulp, particularly in clusters of pyroninophilic cells. Their topographical distribution was not apparently influenced by the immunization. It is suggested that the increased homing of bursa‐derived cells to the spleen may reflect a recruitment of antibody‐forming cell precursors.
Fine structure of receptors for H‐2 antigenic specificities as measured in the PAR assay
Authors: Ramseier H. 
Published: February 2007

AbstractRecognition of a distinct antigenic specificity, H‐2 transplantation antigen 32, could be demonstrated in a congenic strain of mice, using the PAR test. In another congenic strain of mice, recognition of a group of 15 such H‐2 specificities was demonstrated. Both recognition processes could be blocked either by treating target cells, representing the appropriate antigens, with corresponding alloantisera or by treating aggressor cells, carrying receptors for these antigens, with the appropriate anti‐receptor (anti‐RS) antibodies. Antigens recognized in the two strain combinations were of different H‐2 specificities. No cross‐reactivity of inhibitory antisera was found. This indicates that lymphoid cells possess highly specialized receptors which enable competent cells to recognize individual antigenic specificities.
Graft‐versus‐host response induced in vitro by mouse yolk sac cells
Authors: Hofman Florence , Globerson Amiela 
Published: February 2007

AbstractMouse yolk sac cells at the 9th day of gestation were found capable of eliciting, in vitro, a graft‐versus‐host response manifested in splenomegaly. Reactivity of 5 x 104 and 1 x 105 yolk sac cells was greater than that of adult spleen cells tested at the same concentrations. It seems that the immune potential of yolk sac cells at this stage of development is higher than that of the adult spleens.
J‐chain determinants in polymeric immunoglobulins
Authors: Kobayashi K. , Vaerman J.‐P. , Heremans J. F. 
Published: February 2007

AbstractAn antiserum was raised against purified J‐chain from S‐sulfonated human secretory IgA and was tested for its reactivity with secretory IgA, polymeric myeloma proteins of IgA1 and IgA2 subclasses and a Waldenström IgM macroglobulin. The antiserum, which was absorbed with normal human IgG and L‐chains, developed a single precipitin line with the following S‐sulfonated proteins: purified J‐chain, secretory IgA, polymeric IgA1, and IgA2, and IgM. The antiserum also reacted with the same proteins after complete reduction and alkylation. The antiserum did not precipitate the same polymeric immunoglobulins in their native states. At high concentrations, however, native polymeric serum IgA and IgM inhibited the precipitin reaction between the purified J‐chain and its antibodies. In contrast, native secretory IgA displayed no inhibition in this system. After treatment of these immunoglobulins with 8 M urea, 5 M guanidine, or 1 M propionic acid, the J‐chain determinants became accessible and were precipitated with the anti‐J‐chain antiserum, with the exception of IgM which displayed very weak reactivity only after exposure to 5 M guanidine. In conclusion, J‐chain determinants are accessible only to a very limited extent in native serum polymeric IgA and IgM, and none are detectable in the native secretory IgA. Most of the determinants become easily available by mere denaturation of these immunoglobulins with exposure to several kinds of dissociating agents.
Allotypic determinants on the surface of rosette‐forming cells in the rabbit
Authors: Ferrarini M. , Kent S. P. , Munro A. , Kelus A. S. , Catty D. , Coombs R. R. A. 
Published: February 2007

AbstractAntigen‐binding cells to sheep erythrocytes from non‐injected rabbits and from rabbits after a single injection of sheep red blood cells (SRBC) have been detected by the immunocyto‐adherence technique (rosette formation). The expression of immunoglobulin allotypic determinants on these antigen‐binding cells has been investigated by inhibition of rosette formation with anti‐allotype antisera.The results indicate that a and b locus allotypes are expressed by the great majority of rosette‐forming cells (RFC) in the lymph nodes of injected and non‐injected rabbits. Ms3 allotype is expressed by practically all RFC from non‐injected rabbits, while, after injection of SRBC, a population of RFC appears, which does not express this allotype. An antiserum to d 11 consistently failed to inhibit RFC.Pretreatment of lymphocytes from rabbits heterozygous at the b locus with antiserum to only one allelic product produced an inhibition of rosette formation which was approximately half that obtained when antiglobulin reagents to both allelic products were added. The results suggest that in heterozygous animals, the two allelic markers are expressed on two different populations of antigen‐binding cells.Electron microscopy studies on the morphology of RFC showed that the majority of the RFC were formed around small lymphocytes.
Ontogeny of the murine immune system: development of antigen recognition and immune responsiveness
Authors: Yung Lily L. L. , Cheryl Wyn‐Evans T. , Diener E. 
Published: February 2007

AbstractThe grafting of a single spleen colony obtained from irradiated mice protected with 12‐day fetal liver will reconstitute the lymphopoietic and erythropoietic system of irradiation‐deprived syngeneic recipients. Using this experimental model, the early events during the ontogenic development of the immune system were studied in CBA mice. Cells capable of binding radio‐iodine labeled S. adelaide polymerized flagellin were first detectable after 18 to 20 days of lymphopoiesis starting from presumably a single stem cell. However, antibody‐forming cell production after immunization against the same antigen was not demonstrable until days 19 to 26. The same sequential development of antigen recognition (by rosette formation) followed by immune reactivity was observed for sheep red cell antigens, both events occurring later than those for POL. Our observed requirement for the ontogeny of an antigen‐recognition spectrum is compatible with Jerne's theory on the generation of antibody diversity.
Biosynthesis and assembly of IgM. Free thiol groups present on the intracellular subunits
Authors: Stott D. I. , Feinstein A. 
Published: February 2007

AbstractWe have studied the biosynthesis of IgM and its subunits, and the role played by the thiol groups of these subunits in the assembly of the IgM molecule using mouse plasma cell tumor MOPC 104E. In addition to 19 S IgM and light chain, the tumor secretes a small amount of 7 S IgM (IgMs), whereas the cells contain light chain, an HL subunit, IgMs and only a small amount of 19 S IgM. Although the light chain monomers excreted in the urine have blocked thiol groups, the light chain monomers inside the cell and freshly secreted from it have one free thiol group per polypeptide chain. Both the intracellular IgMs and HL subunits also carry free thiol groups, the evidence indicating that there are four per intracellular IgMs subunit. Since there is some evidence that the cysteine residues involved in the formation of the intersubunit bridges may not be free, the polymerization of IgMs to 19 S IgM may be initiated by a rearrangement of thiol groups.
Original antigenic sin at the cellular level. II. Specificity of the antibodies produced by individual cells
Authors: Deutsch Sylvia , Vinit Marie‐Antoinette , Bussard A. E. 
Published: February 2007

AbstractOriginal antigenic sin has been studied at the cell level with mice given a primary injection of meta‐aminobenzoic acid (mB) (coupled to human IgG) and a secondary injection of meta‐sulfanilic acid (mS) (coupled to human IgG), or the reverse. Spleen cell activity against red cells coupled to these haptens was measured by the local hemolysis technique. In order to distinguish between mB specific cells, mS specific cells and cells forming antibodies to both, two procedures were developed:

mB was added in the test medium in order to compete with anti‐mB antibodies and inhibit mB plaques.
Two different types of red cells, pigeon and sheep red blood cells, were coated either with mB or with mS, providing a means of distinguishing three types of plaques: anti‐mS only, anti‐mB only and anti‐mS‐anti‐mB. Both procedures showed that cells specific for the primary hapten only are stimulated by the heterologous booster in the two reciprocal situations. These results are discussed in relation to the specificity of receptors and antibodies and to their affinities towards haptens.
Urinary IgE: a reappraisal
Authors: Stokes C. R. , Hosking C. S. , Turner M. W. , Johansson S. G. O. 
Published: February 2007

AbstractEvidence is presented that previously reported values for urinary IgE were overestimations. This probably arose from nonspecific inhibition in the radioimmunoassay procedure. Gel filtration chromatography suggests that IgE occurs in normal urine as an intact molecule, but at a considerably lower concentration than previously thought.
In vitro primary response in microcultures containing less than fifty thousand lymphoid cells
Authors: Jonard J. , Panijel J. 
Published: February 2007

AbstractA microculture system which permits the survival of very small numbers of active lymphoid cells is here described. These cultures are phage stimulated and are capable of neutralizing the phage by producing specific IgM antibodies. The smaller the number of active cells in the microcultures the greater the percentage of negative microcultures. Positive microcultures are considered to contain at least one “response unit”, the frequency of which is calculated to be 3 per 105 mouse spleen cells. Theoretical implications of these results are also discussed.
Antibody‐induced changes in expression of an immunoglobulin surface antigen
Authors: Knopf P. M. , Destree Antonia , Hyman R. 
Published: February 2007

AbstractAn IgG1‐secreting myeloma possesses Ig‐related surface antigen, Ig‐mem, detected both by a cytotoxic and a 125I‐labeled anti‐Ig binding assay. The properties of Ig‐mem were studied by examining the fate of 125I‐labeled rabbit anti‐Ig and the complement sensitivity of cells sensitized by the binding of labeled antibody at 0 °C. Shifting the temperature to 24 °C or 37 °C leads to a rapid loss of sensitivity to lysis by complement, as well as a loss in the capacity to detect the rabbit antibody on the cell surface. These reactions occur without any appreciable loss of radioactivity from cells at 24 °C. The 125I‐labeled antibody is subsequently degraded to amino acids (detected as iodotyrosine) more rapidly at 37 °C than at 24 °C.We interpret these results as an antibody‐induced interiorization of the IG‐mem, together with its bound antibody. The interiorization reaction does not occur if 125I‐labeled, univalent Fab fragment of the rabbit antibody is used. Instead, most of this reagent remains bound to cells for at least an hour at 24 °C or 37 °C. These latter findings suggest that the bulk of Ig‐mem may not be an immediate precursor of the secreted IgG1, in transit through the plasma membrane.
In vitro activation of mouse lymphocytes in serum‐free medium: effect of T and B cell mitogens on proliferation and antibody synthesis
Authors: Coutinho A. , Möller G. , Andersson J. , Bullock W. W. 
Published: February 2007

AbstractMouse spleen cells were successfully activated by mitogens in serum‐free medium. The T cell mitogen, concanavalin A (ConA), was found to activate DNA synthesis in the presence or absence of serum to the same extent, although the dose response curve was shifted. Thus, concentrations ten times lower were optimally stimulating in serum‐free medium. The strain differences existing with regard to Con A activation were the same whether serum was present or not. B cell mitogens, such as lipopolysaccharide (LPS) and purified protein derivative (PPD) of tuberculin, were equally active in the presence or absence of serum with regard to dose response curves and kinetics for the induction of DNA synthesis.When added to normal spleen cells in culture in the absence of serum, Con A also activated antibody synthesis against a variety of antigens and haptens. It had no such effect on spleen cells from nude animals, indicating that it exerted its B cell‐activating effect via T cells. It was also effective when DNA synthesis in the lymphocytes had been suppressed with mitomycin.LPS and PPD activated antibody synthesis to haptens in normal and nude spleen cells, the response in nude animals being markedly stronger.Since there is virtually no background antibody synthesis in unstimulated cultures in the absence of serum, but a substantial background in serum, it follows that the factor of activation caused by T and B cell mitogens is more pronounced in the absence of serum.
Antigen recognition. III. Effect of phytomitogens on antigen‐receptor capping and the immune response in vitro
Authors: Lee K.‐C. , Langman R. E. , Paetkau V. H. , Diener E. 
Published: February 2007

AbstractConcanavalin A (Con A) has been shown to act differently on bone marrow‐derived (B) cell responses to antigen in vitro depending on the presence or absence of thymus‐derived (T) cells. When T cells were present, Con A suppressed the immune response to polymeric flagellin (POL) of Salmonella adelaide (a T‐independent antigen) and sheep erythrocytes (SRBC) (a T‐dependent antigen). In contrast, when T cells were absent, Con A enhanced the anti‐POL response and allowed an otherwise very low anti‐SRBC response to return to normal levels. Con A inhibited POL‐induced capping in a manner that was apparently independent of the presence of T cells. In a number of cases, the effects noted with Con A were also found with another mitogen, phytohemagglutinin. Some possible implications of these findings on the mechanism of T‐B cell collaboration and the relationship between capping and immune induction are discussed.