bluuebunny/crossref_metadata_2025_split huggingface dataset:
In Vitro Generation of Suppressor Cell Activity: Suppression of in vitro Induction of Cell-Mediated Cytotoxicity
Authors: Hodes Richard J. , Hathcock Karen S. 
Published: December 2022

Abstract
It was observed that when normal mouse spleen cells were cultured alone in vitro (precultured) for 3 to 7 days, these cells lost the ability to generate cell-mediated cytotoxicity (CML) during subsequent in vitro sensitization with allogeneic spleen cells, trinitrophenyl (TNP)-modified syngeneic spleen cells, or syngeneic tumor cells. These precultured cells, which were themselves unable to generate CML, were also shown in mixing experiments to suppress, actively, the generation of CML by freshly explanted spleen cells. Suppression occurred at the sensitization phase of CML, and not at the effector level; supernatants from suppressive precultured cells were not suppressive. Suppression was totally abrogated by the treatment of spleen cells with a T cell-specific rabbit anti-mouse brain serum and complement (RαMB + C) either before or after preculturing, suggesting that a T cell was essential both to the generation of suppressor activity and to its expression. Suppressor activity was entirely absent in precultured nylon wool column-nonadherent spleen cells, a T cell-enriched population containing most of the RαMB + C-sensitive cells in the spleen. Precultured nylon column-adherent cells (T cell-depleted) did have suppressive activity, and a mixture of nylon-adherent and nylon-nonadherent cells was as suppressive after preculture as the precultured unseparated spleen. Moreover, the ability of nylon-adherent spleen cells to generate suppressive activity during preculturing was abrogated by treatment with RαMB + C. Thus, the “spontaneous” generation of CML-suppressive activity was dependent upon a limited subpopulation of splenic T cells isolated in the nylon columnadherent fraction. The relationship of these data to a previously described synergy between subpopulations of normal mouse spleen in the generation of CML is discussed, and the findings related to other suppressor systems described in the literature.
Enhancement of Reaginic and Hemagglutinating Antibody Production by an Extract of Bordetella Pertussis Containing Histamine Sensitizing Factor
Authors: Lehrer Samuel B. , Vaughan John H. , Tan Eng M. 
Published: December 2022

Abstract
The effect of an extract containing the histamine-sensitizing factor (HSF) of Bordetella pertussis on the immune response of mice to ovalbumin was investigated with respect to dose of antigen and adjuvant. Of particular interest was the enhancement of reaginic antibody production. In comparison to the Al(OH)3 induced production of reaginic antibody where low doses of antigen and adjuvant yield high titers of reagin, the HSF extract demonstrated optimal adjuvant activity at high doses of both adjuvant and antigen. The reaginic antibody response was maximal usually by 2 to 3 weeks post-immunization and persisted for long periods of time. The hemagglutinating antibody response was maximal at 8 to 10 weeks post-immunization. The initial treatment of mice with HSF extract plus antigen resulted in the production of memory cells since a subsequent immunization with ovalbumin alone evoked a secondary reaginic antibody response. These observations may have implications in clinical allergy since substances similar to the pertussis factor might be produced by other microbial organisms and these substances could modulate the immunologic response of individuals to common allergens.
Cellular Receptors for Lymphotoxin: Correlation of Binding and Cytotoxicity in Sensitive and Resistant Target Cells
Authors: Tsoukas Constantine D. , Rosenau Werner , Baxter John D. 
Published: December 2022

Abstract
The binding of radioactively labeled lymphotoxin (LT) to both lymphotoxin-sensitive and -resistant cell clones was examined. The sensitive clone had a low-capacity, high-affinity (“specific”) binding component, the curve of which closely followed the cytotoxicity curve of the lymphocyte mediator. The capacity of this binding component was calculated to be about 600 molecules of LT/cell. In addition, there was a low-affinity, high-capacity (“nonspecific”) binding component. In striking contrast, the high-affinity, low-capacity (“specific”) component was absent or greatly diminished from the resistant clone, whereas the low-affinity, high-capacity (“nonspecific”) component was present at a similar level as in the sensitive cells. These binding characteristics closely resemble those observed by us and other investigators working with a variety of steroid hormones in steroid-sensitive and -resistant cell lines.
Antigenic Determinants of Adenovirus Capsids
Authors: Willcox Nicholas , Mautner Vivien 
Published: December 2022

Abstract
Evidence is presented that the type-specific antibody to the adenovirus hexon is not simply the antibody with the highest avidity for cross-reactive determinants, but is a distinct, minority population that recognizes separate determinants. To quantify it, we have developed an inhibition method with radio-immunoprecipitation (RIP) as a sensitive assay for the type-specific antibody that remains after all the excess of cross-reactive antibody has been blocked by heterologous antigen.
During the primary response, 0.1 to 1% of antibody to types 2 or 5 hexon is type-specific, but after boosting, this population may reach 10 to 20%. Antibody to fiber is more than 70% type-specific during primary and secondary responses. The cross-reacting antibody can be removed on immunoabsorbent columns without affecting the virus neutralization titer of the serum.
Cell-Mediated Immunity to Friend Virus-Induced Leukemia
Authors: Ting Chou-Chik , Kirchner Holger , Rodrigues Dennis , Park Joseph Y. , Herberman Ronald B. 
Published: December 2022

Abstract
By employing the 125IUdR release cytotoxicity assay, we have been able to measure the primary and secondary cell-mediated cytotoxic response of C57BL/6 mice to FBL-3 cells, a syngeneic Friend virus-induced leukemia. It was found that the secondary cell-mediated cytotoxic response occurred more rapidly after challenge (within 3 days) than the primary response, and the levels of reactivity were considerably higher. As in the primary response, the secondary cytotoxic reactivity of spleen cells was T cell dependent, being eliminated by pretreatment with anti-θ antibody plus complement. However, the secondary reactivity of pertioneal exudate (PE) cells was not entirely T-cell dependent. The specificity of the secondary cytotoxic response was analyzed by primary or secondary immunization with various tumor cells and by testing of cytotoxic lymphocytes against a variety of target cells. When spleen cells were used for testing, only tumor cells induced by Friend, Moloney, or Rauscher (FMR) leukemia viruses could produce secondary cell-mediated cytotoxic responses against FBL-3 cells. This correlated well with the specificity observed in the in vivo tumor transplantation protection studies. Similarly, spleen cells immune to FBL-3 had appreciable cytotoxicity against tumor cells induced by FMR viruses. The FBL-3 immune mice also gave significant protection against the challenge of FMR leukemias. When PE cells were used for testing, they gave a broader spectrum of reactivity. These cells usually gave higher levels of cytotoxicity against tumor cells induced by FMR viruses, but also gave less, but appreciable, cytotoxicity against non-FMR tumors. The latter reactivity might be related to the antigens induced by the murine endogenous type C viruses.
Kinetics of the Antibody Response to Type III Pneumococcal Polysaccharide (SSS-III)
Authors: Jones Jeffrey M. , Amsbaugh Diana F. , Prescott Benjamin 
Published: December 2022

Abstract
A simple method was described for the preparation of 125I-labeled type III pneumococcal polysaccharide (SSS-III*) with a high specific radioactivity which retained the physical and immunologic properties of native SSS-III. SSS-III* was used to study the serum and tissue levels of antigen, as well as its excretion, after i.p. injection. When an optimally immunogenic dose (0.5 µg) of antigen was given, τ;90% of the injected antigen was excreted during the first 3 days after injection; however, after day 3, the SSS-III* which remained in each mouse was firmly bound to various tissues, and &lt;5 ng SSS-III* was released into the circulation daily. SSS-III* was also used in a Farr test to measure serum antibody levels; the kinetics for the appearance of PFC/spleen and serum antibody levels were measured at 24-hr intervals after immunization with 0.5 µg of antigen. Maximum PFC/spleen were observed on day 4 after immunization whereas the peak serum antibody level was seen on day 5. The decay of serum antibody level from its maximum value was much slower than that of the PFC/spleen. The data describing the distribution of SSS-III in vivo and the measurement of serum antibody levels indicated that treadmill neutralization was not a factor in determining the serum antibody levels after immunization with an optimally immunogenic dose of SSS-III.
Purification of the Sixth and Seventh Component of Human Complement without Loss of Hemolytic Activity
Authors: Podack Eckhard R. , Kolb William P. , Müller-Eberhard Hans J. 
Published: December 2022

Abstract
Procedures for the isolation of the human complement proteins C6 and C7 have been described. These procedures allow isolation of the two proteins without any loss of hemolytic activity. Apparent activity gains of 160% and 140% were observed for C6 and C7, respectively, when the activity of the isolated proteins was compared with their activity in serum. The recovery of C6 was 3.5 to 11% and that of C7 was 7 to 13% of the amount present in serum. C6 has a m.w. of 128,000 and an electrophoretic mobility at pH 8.6 of -2.6 × 10-5 cm2 s-1 v-1. C7 has a m.w. of 121,000 and an identical electrophoretic mobility. With 3 × 107 assay cells, 63% hemolysis was achieved with 1 ng of C6 and 3.8 ng C7. On polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate and after reduction with mercaptoethanol, C6 and C7 behaved as single polypeptide chain proteins.
Identification of a Macrophage-Specific Cell Surface Antigen
Authors: Stinnett J. Dwight , Kaplan Alan M. , Morahan Page S. 
Published: December 2022

Abstract
A mouse-specific macrophage antigen (MSMA) was identified in NP-40 extracts of 125I-radiolabeled mouse peritoneal macrophages by using a rabbit anti-mouse macrophage serum (AMS) and SDS-polyacrylamide gel electrophoresis. The antigen was shown to have a m.w. of 83,000 daltons and was present on both normal and “activated” peritoneal macrophages. MSMA was also present on syngeneic adherent spleen cells, allogeneic peritoneal macrophages, a mouse macrophage cell line (P388D1), and exhibited some cross-reactivity with peritoneal macrophages from closely related species (rats and hamsters). MSMA was not present on nonadherent peritoneal exudate cells, spleen cells, erythrocytes, thymocytes, or bone marrow cells. Extensive absorptions of AMS with thy - mocytes and erythrocytes from mice were necessary to remove other antibodies that reacted with other mouse membrane antigens. An antiserum directed against a specific membrane antigen has great potential in elucidating structure-function relationships with regard to a number of macrophage activities.
Spontaneous Cytotoxicity (SCMC) of Normal Human Lymphocytes against a Human Melanoma Cell Line: A Phenomenon Due to a Lymphotoxin-Like Mediator
Authors: Peter Hans H. , Eife Rudolf F. , Kalden Joachim R. 
Published: December 2022

Abstract
Spontaneous cell-mediated cytotoxicity (SCMC) of normal human lymphocytes against various allogenic tumor cell lines has recently been identified as a non-T lymphocyte function. In this study evidence is presented that SCMC against a human melanoma cell line (IGR3) involves a nonspecific lymphotoxin-like mediator(s) (LT), which is rapidly produced by lymphocytes that are retained on IgG-anti-IgG columns. LT was shown to inhibit in 48-hr cultures the DNA synthesis of growing IGR3 and HeLa cell monolayers. Furthermore, in short term 51Cr-release assays using IGR3 target cells, LT increased strongly the SCMC of normal allogeneic lymphocytes, although it exhibited little cytotoxicity by itself in this assay. LT was detectable in cell-free supernatants harvested after 6 hr from co-cultures of IGR3 melanoma cells and normal effector lymphocytes, but not in supernatants from melanoma cells alone or lymphocytes alone. Lymphocyte preparations that had been passed through IgG-anti-IgG columns had lost the capacity to generate LT and were poor effectors in SCMC. However, in the presence of LT, a small proportion of null cells, which pass through IgG-anti-IgG columns, was capable of inducing strong SCMC. Absorption of the supernatants, containing LT activity, with an insolubilized rabbit-anti-human IgG antiserum did not remove the mediator, suggesting that it is not an immunoglobulin.
The Role of the Capsular Polysaccharide in the Activation of the Alternative Pathway by the Pneumococcus
Authors: Winkelstein Jerry A. , Bocchini Joseph A. , Schiffman Gerald 
Published: December 2022

Abstract
Previous studies have shown that when pneumococci are incubated in normal, nonimmune serum, they activate the alternative pathway and opsonically active C3b is fixed to the surface of the organism. Other studies have demonstrated that C3-dependent opsonization via the alternative pathway plays a significant role in the nonimmune host's defense against the pneumococcus. The present studies concern the role of the capsular polysaccharide in initiating the activation of the alternative pathway by the pneumococcus.
Some pneumococcal capsular polysaccharide types, but not all, are able to activate the alternative pathway. Soluble purified capsular polysaccharide types 1, 4 and 25 activate the alternative pathway, whereas types 2, 3, 14, and 19 do not. Since the capsular polysaccharides exist in their native form attached to the pneumococcal surface, selected capsular polysaccharides were also tested for their ability to activate the alternative pathway when attached to a particulate carrier, sheep erythrocytes. Capsular polysaccharide types 2 and 3 failed to activate the alternative pathway when attached to sheep erythrocytes, paralleling the results obtained when these capsular polysaccharides were in solution. In contrast, the type 25 capsular polysaccharide not only activated the alternative pathway when attached to sheep erythrocytes, as it had when in solution, but is also initiated alternative pathway-mediated lysis of the erythrocytes.
The capsular polysaccharide is not required for the activation of the alternative pathway by the pneumococcus. Although all types of encapsulated pneumococci are able to activate the alternative pathway, not all the purified capsular polysaccharide types are able to do so. In addition, a nonencapsulated pneumococcus, derived originally from a type 2 organism, activates the alternative pathway as well as a fully encapsulated type 2 pneumococcus.
Isolation and Characterization of Rabbit Antibodies Directed against Group a Allotypic Determinants
Authors: Aasted Bent , Sogn John A. , Kindt Thomas J. 
Published: December 2022

Abstract
The L chains of rabbit antibodies directed against group a allotypes exhibited in many instances a high degree of homogeneity as measured by L chain banding patterns in alkaline urea polyacrylamide gels. Amino terminal sequence analyses were carried out on six L chain preparations from antibodies isolated from individual antisera or from pools of antisera. The same major amino terminal sequence, Ala-Val-Val-Met, was observed for each of these preparations indicating that anti-allotype antibodies preferentially select L chains from a single subgroup.
The antiallotype antibodies were isolated from antisera by elution from IgG immunoadsorbent columns in yields ranging from 0.3 to 1 mg/ml antibody. The specificity of the isolated antibodies was demonstrated by radioimmune assays. Certain fractions were contaminated with a protein that had properties similar to rabbit serum albumin. This contamination was minimized by preadsorption of the antisera. The antibodies were primarily of the IgG class as shown by immunoelectrophoresis and by m.w. of the H and L chains on SDS gels.
The Effect of Thiols on the Immunologic Release of Slow Reacting Substance of Anaphylaxis
Authors: Orange Robert P. , Moore Elizabeth G. 
Published: December 2022

Abstract
In the presence of L-cysteine, a selective and marked enhancement of the in vitro, immunologic release of slow reacting substance of anaphylaxis (SRS-A) from human peripheral leukocytes, sensitized monkey lung fragments, and sensitized guinea pig lung fragments was observed. In the rat, cysteine, but not sodium sulfide, enhanced the calcium ionophore (A23187)-induced release of SRS-A in vitro from mixed rat peritoneal cells and in vivo from the rat peritoneal cavity. Pretreatment of rats with cysteine also enhanced the IgGa- and anti-rat IgE-mediated release of SRS-A in vivo in the rat. These studies indicate a common biochemical mechanism involved in the formation and release of SRS-A from these different tissues and cells and further confirm the observation that the rat mast cell is not a major source of SRS-A in the rat.
Cell Surface Immunoglobulin
Authors: Melcher Ulrich , Uhr Jonathan W. 
Published: December 2022

Abstract
125I-membrane IgM, 125I-membrane IgD-like molecules, and their constituent chains from iodinated murine splenocytes were characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The apparent m.w. of the heavy chains decreased as the acrylamide concentration was raised. The membrane µ-chain had a slower mobility than did µ-chain from secreted IgM. Unreduced IgM and IgD-like molecules had mobilities consistent with an H2L2 structure. Intact IgD-like molecules were replaced after overnight dialysis by molecules with the properties of HL. Unreduced surface IgM had a slower mobility than that of monomeric IgM obtained by partial reduction of secreted IgM.
The Class-Specific Immunoglobulin Composition of Fluids Obtained from Various Levels of the Canine Respiratory Tract
Authors: Kaltreider H. Benfer , Chan Maria K. L. 
Published: December 2022

Abstract
Sensitive and specific radioimmunoassays capable of accurately measuring the three major classes of canine immunoglobulins in the 50 to 200 ng/ml range were developed. The concentrations of IgG, IgA, and IgM in samples of fluid obtained from various levels of the canine respiratory tract (stimulated saliva, tracheal washes, and bronchopulmonary lavage supernatants) and in serum were determined by using the radioimmunoassays. The composition of the immunoglobulin classes, expressed as per cent of the total immunoglobulin content of each sample, differed markedly among the respiratory tract-derived fluids and between respiratory fluids and serum. Pilocarpine-stimulated saliva contained predominantly IgA while bronchial washes contained predominantly IgG. The contents of IgA and IgG in tracheal washes were intermediate between those of stimulated saliva and bronchial washes. There appeared to be a progressive decrease in the content of IgA (83% to 19%) and a progressive increase in the content of the IgG (6.3% to 75%) as sampling proceeded from the upper to the lower respiratory tract. The mean IgG/IgA ratios were as follows: stimulated saliva, 0.1; tracheal washes, 2.1; bronchial washes, 4.1; and serum, 23.2. All respiratory tract-derived fluids contained small amounts of IgM. Local and systemic immunization with sheep erythrocytes failed to alter the per cent composition of immunoglobulins in bronchial washes during the primary immune response. The results demonstrate major differences in the composition of immunoglobulins derived from the upper as opposed to the lower respiratory tract. The findings suggest that functional differences may exist in the immunologic apparatus associated with various levels of the respiratory tract.
In Vitro Response of Subpopulations of Human Tonsil Lymphocytes
Authors: Delespesse G. , Duchateau J. , Gausset Ph. , Govaerts A. 
Published: December 2022

Abstract
Human tonsil lymphocytes have been separated into three subpopulations of cells: purified B cells and two subsets of purified T cells (F1 and F2). B cells were obtained by rosetting with neuraminidase treated SRBC. F1 and F2 were separated by filtration on a nylon wool column using different speeds of elution. Purified B cells contained less than 5% T cells, the T cells preparations contained less than 5% B cells for F1 and 10 to 15% for F2, respectively. A significant contamination in cells not identified by any B or T marker was observed in purified B cells and in F1. Adherent cells enhanced the response of each lymphocyte population to PHA and Con A. This explained the paradoxically low responsiveness of the purified T cells. Purified B cells did not respond to these mitogens in different culture conditions. However, a small B cell response was observed when they were cultured in the presence of mitomycin-treated T cells. Striking was the enhancing effect of B cells on the T cell response to PHA and Con A. This enhancing effect was observed even when B cells were treated with mitomycin or depleted in adherent cells. The comparison of the F1 and F2 response suggested that they contained distinct types of T cells.
Neuraminidase Reversal of Resistance to Lysis of Herpes Simplex Virus-Infected Cells by Antibody and Complement
Authors: Tompkins W. A. F. , Seth P. , Gee S. , Rawls W. E. 
Published: December 2022

Abstract
The susceptibility to lysis by antibody and complement was examined in four human cell lines. The cells were infected with herpes simplex virus type 1 and lysis was assessed by the 51Cr release test by using antibodies to herpes simplex virus and guinea pig serum as a source of complement. The four cell lines were found to differ in their susceptibility to lysis, although virus replication was readily demonstrated in the different cell lines. By indirect immunofluorescence, no differences in the expression of virus antigens at the surface of the cells could be found between the different cell lines. Treatment of cells with neuraminidase markedly enhanced the sensitivity of the cells which were relatively insensitive to lysis. The enhancement of susceptibility to lysis by neuraminidase occurred if cells were treated before reaction of the cells with antibody and if the cells were reacted with antibody before treatment with the enzyme. No enhancement was observed when cells were reacted with antibody and complement before neuraminidase treatment. Neuraminidase treatment did not seem to enhance appreciably the quantity of antibody which reacted at the cell surface. The observations suggest that surface properties of certain cells render the cells resistant to lysis by antibody and complement and that the resistance to lysis can be abrogated by treating the cells with neuraminidase.