bluuebunny/crossref_metadata_2025_split huggingface dataset:
SIMILARITIES IN THE LIGHT CHAINS OF ANTI-γ-GLOBULINS SHOWING CROSS-IDIOTYPIC SPECIFICITIES
Authors: Kunkel H. G. , Winchester R. J. , Joslin F. G. , Capra J. D. 
Published: June 2004

A marked homogeneity of the light chains was observed in an analysis of 17 IgM proteins with anti-γ-globulin activity. The V region subgroups of the light chains were determined by both sequence and antigenic analysis. The latter procedure permitted large scale screening for comparisons with control proteins. The two methods showed general agreement in the determination of Kappa III proteins; all proteins positive by antigenic analysis were also positive by sequence but exceptions were noted in the opposite direction. The anti-γ-globulins showed by antigenic analysis a 92% incidence of VK III light chains as compared to an incidence of 27% among 81 control proteins without this activity. A similar selection was observed for an antigen (VK III b) which subdivided the kappa III proteins.
The major Wa group of anti-γ-globulins which had been delineated previously on the basis of cross-idiotypic specificity was primarily responsible for the special light-chain selection. All the proteins of this group contain VK III light chains and all were of the VK III b type. Current evidence indicates that additional light-chain similarities were involved in the cross-idiotypic specificity of the Wa group. It thus appears that for the anti-γ-globulins various levels of selection of light chains are manifest ranging from a preponderance of kappa type, of kappa III subgroup, of kappa III b sub-subgroup and perhaps of still further subdivisions to account for the cross-idiotypic specificity.
HORMONE-LIKE ACTIVITY OF A THYMUS HUMORAL FACTOR ON THE INDUCTION OF IMMUNE COMPETENCE IN LYMPHOID CELLS
Authors: Kook Abraham I. , Trainin Nathan 
Published: June 2004

Experiments reported here were performed to understand the mechanism by which THF increases the immunocompetence of spleen cells from NTx mice.
Dibutyryl cAMP or substances which increase intracellular levels of cAMP in lymphocytes such as Poly(A:U), theophylline, or PGE2 were shown to mimic the effect of THF and confer reactivity in an in vitro GvH response to spleen cells from NTx mice. Flufenamic acid, an antagonist to PGE2, was shown to inhibit the induction of competence by this substance. It was found that THF induces competence by activating membranal adenyl cyclase which leads to a rise in intracellular cAMP in thymus-derived cells only. These biochemical changes occur before antigenic stimulation and are unrelated to antigenic challenge.
These findings indicate that THF exerts its effect via cAMP and are in agreement with the concepts which permit to classify THF as a thymus hormone.
CELL-MEDIATED IMMUNITY AGAINST BESNOITIA AND TOXOPLASMA IN SPECIFICALLY AND CROSS-IMMUNIZED HAMSTERS AND IN CULTURES
Authors: Hoff Richard L. , Frenkel J. K. 
Published: June 2004

The capacity of hamster peritoneal cell populations to control viability and growth of Besnoitia and Toxoplasma organisms was assessed in vivo and in vitro. Immunized hamsters reduced the homologous organisms 100- to 10,000-fold over a 5-day period, but the heterologous infection increased 100- to 1,000-fold in numbers, similar as in the nonimmune controls. Passively administered antibody was ineffective although lytic cofactors were supplied by hamsters.
In cultures, peritoneal cells from Besnoitia-immune hamsters delayed the growth of homologous parasites to an average of 38.5 h per division; however, in Toxoplasma-immune and nonimmune cells, Besnoitia divided every 12.8 h. Specificity of immunity was pronounced against both infections. With cross-infections, Toxoplasma-immune cultures did not effectively delay Besnoitia growth; however, Besnoitia-immune cultures reduced Toxoplasma growth by one-half. Co-cultivation experiments demonstrated that specifically committed lymphocytes could instruct macrophages to reduce the homologous organism 10-fold, whereas heterologous organisms were reduced only 2-fold.
Lymphocyte supernatants initiated hypersensitivity as indicated by macrophage activation and giant cell formation in culture. However, these supernatants did not transfer infection immunity. Lymphokines could account for the hypersensitivity phenomena, but cell-mediated infection immunity in this model required close lymphocyte-macrophage proximity.
These studies indicate that a number of distinct processes including delayed hypersensitivity, macrophage activation, and specific cellular immunity are acting simultaneously during latent Besnoitia infection of hamsters. All three processes are mediated by lymphoid cells and appear to be specifically induced. Although activated macrophages develop some heightened nonspecific capabilities, these were several orders of magnitude below the specific effects.
FURTHER EVIDENCE OF THE TOXICITY OF NaCl
Authors: Dahl Lewis K. , Tuthill Ralph 
Published: June 2004

The spontaneously hypertensive rat (SHR) of Okamoto and Aoki (4) develops significant hypertension without added dietary salt. Many patients with hypertension have little or no alteration in blood pressure from increments or decrements of salt intake. Such observations have led to a widespread belief that dietary NaCl is important in hypertensives only if blood pressure changes are observed after changes in NaCl intake. Such a simplistic view of hypertension fails to take into account the possibility that morbidity and mortality might be lowered by restricting dietary NaCl, without a concomitant lowering of blood pressure.
The effect of a high NaCl intake for periods up to 1 yr has been studied in the SHR with the following conclusions: (a) NaCl accelerated the rate at which hypertension developed in both sexes. (b) The ultimate levels of blood pressure reached by males on either high or low salt diets were similar, however. (c) In females, (1) on high NaCl the average blood pressure ultimately became indistinguishable from males whereas (2) on low NaCl pressure remained significantly lower than that of males. (d) The addition of NaCl to the regimen had a devastating effect on mortality of both sexes and was not directly correlated with the level of blood pressure. Earlier reports were reviewed bearing on the possibility that NaCl is inimical to blood vessels without a necessary relationship to its hypertensinogenic effect. It was concluded that restriction of dietary NaCl would reduce morbidity and mortality in hypertension, whether or not blood pressure was reduced by such measures.
LYMPHOCYTE PROLIFERATION IN VITRO INDUCED BY HAPTEN AUTOLOGOUS PROTEIN CONJUGATES
Authors: Rubin Bent , Wigzell Hans 
Published: June 2004

Immune lymph node cells from guinea pigs respond to soluble antigen in vitro by an increase in DNA synthesis. Optimal conditions for this proliferative response were studied in the present article. Under such conditions, immune cells showed increasing responses with increasing antigen concentration in vitro, the threshold dose of activation frequently being as low as 0.02 µg per culture. In contrast, normal lymph node cells (from FCA-stimulated animals) did only respond to antigen at very high doses (20 mg/culture), and immune cell dilution studies could be performed in normal cells without changing the kinetics of the antigen specific response of immune cells.
Fractionation on anti-Ig columns indicated that purified, immune T lymphocytes were quite capable of proliferating in vitro upon antigen stimulation. However, our attempts to adsorb the proliferating cells onto chemically defined immunoadsorbants failed despite the fact that immune B cells (as measured by the rosette assay) were retained almost completely by such a procedure.
Purified, immune T lymphocytes from guinea pigs immunized with different antigen concentrations in vivo and/or obtained at different times after immunization were tested for a differential sensitivity toward antigen-induced DNA synthesis in vitro. However, we were not able to demonstrate any regular increase in sensitivity to antigen in vitro, and if found, it seemed to be more dependent upon the number of antigen reactive cells in the population studied rather than upon differences in the average avidity of the receptors on the cells proliferating in vitro. The results in the present article are discussed in relation to current knowledge and hypotheses on T-lymphocyte receptors.
BINDING OF AGGREGATED γ-GLOBULIN TO ACTIVATED T LYMPHOCYTES IN THE GUINEA PIG
Authors: van Boxel John A. , Rosenstreich David L. 
Published: June 2004

Heat-aggregated guinea pig γ-globulin was shown to bind to the surface membrane of a subclass of guinea pig T lymphocytes. Cells of this subpopulation were identified as T lymphocytes because these cells did not stain for surface Ig (a B-cell marker) but did form spontaneous E-rosettes with rabbit erythrocytes (a T-cell marker). A strikingly high proportion of such aggregate-binding (Agg+), E-rosette-forming (E-rosette+), but surface Ig-negative (Ig-) cells were found in an inflammatory exudate. Thus purified peritoneal exudate lymphocytes (PELs) are known to consist of over 90% T cells, and 59% of these cells bound aggregates. 10% of these Agg+ Ig- E-rosette+ cells were found in draining lymph node cell populations and none in thymus cell populations.
The high frequency amongst PELs suggested that these Aggregate+ Ig- E-rosette+ cells might be activated T cells as these are known to occur in high proportion in PEL populations. Confirmatory evidence for this postulate was provided by the striking increase (from 10% to 46%) of Ig- E-rosette+ cells that bound aggregates when lymph node cells were activated by antigen stimulation in vitro.
INTERACTION OF CHOLERA TOXIN AND TOXIN DERIVATIVES WITH LYMPHOCYTES
Authors: Holmgren J. , Lindholm L. , Lönnroth I. 
Published: June 2004

The interaction of cholera toxin and a number of toxin derivatives, containing different proportions of light and heavy toxin-composing subunits (L and H), with mouse lymphocytes was studied. Experiments with [125I]toxin showed that a single cell can rapidly, within minutes, bind up to 40,000 molecules of toxin, the association constant was estimated to 7 ± 4 x 108 liters/mol, and binding was found to be very similar at 37°C and 5°C. Immunofluorescence studies revealed that the toxin attachment is located on the cell surface, and that purified L subunit but not H subunit binds to the cells. A natural cholera toxoid, built up by aggregated L subunits, showed almost identical binding properties as toxin to the cells. Pure GM1 ganglioside, the proposed membrane receptor structure for toxin, prevented entirely the cellular binding of both toxin and toxoid.
Cholera toxin in concentrations down to approximately 5 x 10–11 mol/liter (corresponding to 10 bound molecules/cell) inhibited thymus cells from being stimulated to DNA synthesis by concanavalin A (con A), and spleen cells from such stimulation by phytohemagglutinin. The GM1 ganglioside but not a series of other pure structurally related gangliosides and neutral glycosphingolipids neutralized this toxin activity. Toxin derivatives which, in similarity with toxin, possessed H as well as L subunits but in other proportions, were potent inhibitors of con A-induced thymocyte stimulation, whereas the natural toxoid (aggregated L subunits), purified toxin L subunit and purified toxin H subunit were up to 300-fold less active on a weight basis. The capacity of cholera proteins to inhibit con A-induced thymocyte stimulation correlated well with their activity in the rabbit intradermal toxicity assay.
The inhibitory action of cholera toxin on con A-induced thymocyte stimulation did not depend on decreased cell viability from the toxin treatment, nor was it caused by a reaction between toxin and con A. [125I]con A bound equally well to the cells when toxin was present as when it was absent, which proves that the toxin did not compete for cellular con A receptors. Nor did the toxin seem to disturb the general mobility of membrane receptors or their ability to accumulate in caps.
It is concluded that the L type of subunit confers rapid and firm binding of cholera toxin to lymphocyte membranes, probably to GM1 ganglioside receptors. For biologic activity the additional presence of H subunit is important. One manifestation of toxin action on lymphocytes is inhibition of lectin-induced DNA synthesis; probably this effect relates to the ability of cholera toxin to raise the levels of intracellular cyclic 3'5'-adenosine monophosphate.
ONTOGENY OF B LYMPHOCYTES
Authors: Gelfand Michael C. , Sachs David H. , Lieberman Rose , Paul William E. 
Published: June 2004

The frequency of lymphocytes bearing complement receptors in the spleens of 2-wk old mice appears to be controlled by two independent genes. The presence of a "high" allele at either locus leads to intermediate or high frequency of CRL at 2 wk of age. One of the genes controlling complement receptor lymphocyte (CRL) frequency (CRL-1) is linked to the H-2 complex. Thus, in progeny of (AKR x DBA/2)F1 x DBA/2, all mice with a low frequency of CRL at 2 wk of age are homozygous for the H-2 type of the low CRL parent (DBA/2). Furthermore, in the B10 series of congenic mice, CRL frequency at 2 wk of age is similar to the frequency in the donor of the H-2 region. Thus, C57BL/10, B10.BR, and B10-D2 mice are all of the low CRL type while B10.A mice are intermediate in CRL frequency at 2 wk. C57BR and DBA/2, the donors of the H-2 complex of the B10.BR and B10.D2, respectively, are of low CRL type while the A/WySn, the donor of the H-2 complex in the B10.A, is an intermediate CRL strain. Similarly in the A/WySn series of congenic mice, A.CA, A.SW, and A.BY are all low CRL strains while the A/WySn is intermediate.
Studies of CRL frequency in mice with recombinant H-2 chromosomes (B10.A(2R), (4R), and (5R); B6/TL+; and A/TL-) indicate that CRL-1 is to the right of the Ss-Slp genes and to the left of Tla.
POTENTIATION OF T-CELL-MEDIATED IMMUNITY BY SELECTIVE SUPPRESSION OF ANTIBODY FORMATION WITH CYCLOPHOSPHAMIDE
Authors: Lagrange P. H. , Mackaness G. B. , Miller T. E. 
Published: June 2004

Delayed-type hypersensitivity (DTH) appears in mice immunized with less than an optimal immunogenic dose of sheep red blood cells (SRBC), but is blocked progressively as antibody production increases in response to larger doses of SRBC. Treatment with cyclophosphamide (CY) was shown to release T cells from this inhibitory influence of the humoral response, and cause enhancement of DTH. The magnitude of this enhancing effect on T-cell activity was markedly dependent on the time of treatment relative to the time of immunization, and on the time chosen for measuring DTH. The reasons for these pronounced effects of timing are threefold: (a) CY given before antigenic stimulation has a long-lasting effect on antibody formation, but no apparent effect on the precursors of activated T cells. (b) After antigenic stimulation, T cells also become susceptible to CY. (c) The production of a nonspecific participant (monocyte) in the DTH reaction is also suppressed by CY, though the supply of circulating monocytes is not immediately affected by the drug.
The differential effect of CY on T and B lymphocytes depends on the differing physiological states of the majority of cells that make up these two populations. The former are resting cells that are insensitive to CY until exposed to specific antigen, while the latter are drawn from a rapidly replicating precursor pool and are susceptible to CY at all times.
CELL-TO-CELL INTERACTION IN THE IMMUNE RESPONSE
Authors: Basten A. , Miller J. F. A. P. , Sprent J. , Cheers C. 
Published: June 2004

Specific immunological tolerance was induced in CBA mice by a single injection of deaggregated fowl immunoglobulin G (FγG). The unresponsive state was stable on adoptive transfer and irreversible by pretreatment of tolerant cells with trypsin. Tolerant spleen cells could suppress the response of normal syngeneic recipients. They also suppressed the adoptive primary response of spleen cells to FγG in irradiated hosts. The inhibitory effect was on the indirect (7S) plaque-forming cell (PFC) response.
Incubation of the tolerant cell population with anti-θ serum and complement reversed the suppressor effect. Furthermore, the addition of purified T cells from normal donors restored the capacity of the anti-θ serum-treated tolerant cells to transfer an adoptive response to FγG. The existence of FγG-reactive B cells was supported by the demonstration of normal numbers of antigen-binding cells in the spleen and thoracic duct lymph from tolerant animals. Moreover, the formation of caps by these cells implied that they could bind antigen normally.
These experiments provided direct evidence for the existence of suppressor T cells in the tolerant population. Further evidence was derived from examination of the effect of antigen "suicide". Tolerant spleen cells were treated with radioactive FγG under conditions known to abrogate T-cell helper function. When these cells were transferred together with normal spleen cells into irradiated hosts, suppression of the primary adoptive response to FγG was no longer observed. Inhibition of an adoptive secondary response to FγG was obtained by transferring tolerant spleen cells with primed B cells provided high doses of tolerant cells were used. By contrast low doses exerted a helper rather than a suppressor effect in this system.
SELECTIVE ROLES OF THYMUS-DERIVED LYMPHOCYTES IN THE ANTIBODY RESPONSE
Authors: Tada Tomio , Takemori Toshitada 
Published: June 2004

Passively transferred thymocytes and spleen cells from donors primed with keyhole limpet hemocyanin (KLH) exerted differential suppressive effect on IgM and IgG antibody responses of syngeneic recipients immunized with DNP-KLH depending primarily on the time when KLH-primed cells were transferred. This was demonstrated by the decrease in the numbers of DNP-specific direct and indirect PFC in the spleen of the recipients given KLH-primed cells at different times during primary and secondary immunization. Whereas the cell transfer simultaneously with or 2 days after the primary immunization produced only slight suppression of the peak IgM antibody response, it caused profound suppression of late IgM and IgG antibody responses. By contrast, the cell transfer 3 days after the immunization produced immediate suppression of the ongoing IgM antibody response resulting in its earlier termination, while being unable to prevent the induction of IgG antibody response. KLH-primed cells could moderately suppress the secondary anti-DNP antibody response, in which IgG antibody response was found to be slightly more sensitive than IgM antibody response to the suppressive influence of KLH-primed cells.
The suppressive effect of the KLH-primed spleen cells was completely eliminated by the in vitro treatment of the cells with anti-θ and C before cell transfer, indicating that cells responsible for the suppression are, in fact, T cells. The suppression of DNP-specific antibody response by KLH-primed T cells was achieved only if the recipients were immunized with DNP-KLH but not with DNP-heterologous carrier, suggesting that direct interaction between T and B cells is necessary for the suppression of the antibody response. It is concluded that susceptibility of B cells to the specific suppressive influence of T cells is inherently different depending on the differentiation stage of B cells and on the immunoglobulin class they are destined to produce.
CELL-MEDIATED IMMUNE RESPONSES IN VITRO
Authors: Peavy Duane L. , Pierce Carl W. 
Published: June 2004

The effects of soluble concanavalin A (Con A) or Con A-activated spleen cells on the generation of cytotoxic lymphocytes (CL) in mixed leukocyte cultures (MLC) were examined. Mitogenic concentrations of soluble Con A or small numbers of Con A-activated spleen cells substantially inhibited CL responses. The suppression was partial rather than absolute and was critically dependent upon the concentration and time of addition of soluble Con A or Con A-activated spleen cells to the MLC.
Suppressive effects of Con-A activated spleen cells were mediated by T cells since suppressor cell activity was abrogated by treatment of spleen cells with anti-θ serum and complement before or after Con A activation. X irradiation of spleen cells before Con A treatment also abrogated generation of suppressor cell activity. After activation by Con A, however, the function of suppressor cells was radioresistant.
Although the precise mechanism(s) of suppression is, as yet, unknown, the precursors of CL must be exposed to Con A-activated cells during the early phases of the immune response for suppression to occur. Kinetic studies revealed that suppression of CL responses was not due to a failure to initiate an immune response, but represented a response which developed initially, but subsequently aborted. The relevance of these observations to the concepts of T-cell-T-cell interaction and regulatory control of immune responses by T cells is discussed.
CLONAL CHARACTER OF F1 HYBRID LYMPHOCYTE SUBSET RECOGNITION OF PARENTAL CELLS IN ONE-WAY MIXED LYMPHOCYTE CULTURES
Authors: Gebhardt Bryan M. , Nakao Yoshinobu , Smith Richard T. 
Published: June 2004

Proliferation of F1 hybrid lymphocytes in mixed lymphocyte cultures is stimulated by mitomycin-blocked parental cells. The demonstration of this phenomenon using F1 hybrids derived from congenic lines of mice establishes that the stimulation is controlled by genes in or closely linked to the major histocompatibility locus chromosome region. In agreement with the finding that tumor-bearing mice have an increased capacity for primary alloantigen recognition, it was observed that the F1 hybrid response to parent was also augmented by tumor bearing.
Chromosomal analysis of dividing cells in one-way mixed cultures confirms that F1 cells, and not the blocked parental cells, enter mitosis. Stimulation of F1 cells by a soluble mediator liberated by the parental cells was not observed and mitomycin blocking of parental cells seems to be a completely effective blocking agent ensuring that parental cells can not enter DNA synthesis.
The specificity and clonal nature of F1 recognition of parent was demonstrated using a 5-bromodeoxyuridine-suicide procedure. Distinct clones of lymphocytes in F1 spleen cell populations seem to recognize one or the other parent, but not both, in such experiments. These observations and others in tumor systems suggest that most or all heterozygous organisms may possess potentially self-reactive clones of lymphocytes.
LONG-TERM ESTABLISHMENT OF A HUMAN PLASMACYTE CELL LINE DERIVED FROM A PATIENT WITH IgD MULTIPLE MYELOMA
Authors: Jobin M. E. , Fahey J. L. , Price Z. 
Published: June 2004

Cell line LA-49, derived from pleural fluid cells of a patient with IgD multiple myeloma, was established in culture and maintained for more than 1 yr. The D-myeloma protein produced in culture was similar to the serum D-myeloma protein in electrophoretic mobility and in delta- and lambda-chain antigens.
The plasma cell tumor culture, LA-49, differed from numerous immunoglobulin-producing B-lymphoblastoid cell lines established in this laboratory in: (a) Morphology (revealing various stages of maturation); (b) type of immunoglobulin produced (IgD vs. IgM, IgG, and/or, rarely, IgA); (c) growth characteristics (requirement of plasmacyte-stimulating factor); and (d) chromosomal features (polyploid vs. pseudodiploid).
A growth factor was needed for cell division and maintenance of culture viability. This factor was supplied readily by irradiated feeder layers of normal human fibroblasts or conditional media from fibroblast cultures. Preliminary characterization of this factor revealed it to be a protein with a mol wt of approximately 150,000 daltons.