bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of Radioimmunoprecipitation for the Detection of Bovine Leukemia Virus Infection in Domestic Cattle
Authors: Devare Sushilkumar G. , Chander Satish , Samagh Bakhshish S. , Stephenson John R. 
Published: December 2022

Abstract
The potential application of a recently developed radioimmunoprecipitation test for antibody directed against the major structural protein of bovine leukemia virus was evaluated for use in detection of BLV-infection in domestic cattle. This technique was found to be considerably more sensitive than serologic procedures currently being utilized for this purpose. Radioimmunoprecipitation was also shown to have distinct advantages as compared to hematologic criteria, such as specified by Bendixen's index, for identification of BLV-infected animals. By the use of radioimmunoprecipitation, high levels of antibody to BLV were demonstrated in sera of animals with confirmed adult lymphosarcoma, but not in animals with a less common sporadic form of the disease which occurs in calves.
The Structural Basis of Rabbit VH Allotypes: Serologic Studies on a1 H Chains with Defined Amino Acid Sequence
Authors: Margolies Michael N. , Cannon L. Edward , Kindt Thomas J. , Fraser Blair 
Published: December 2022

Abstract
The amino acid sequences for the VH regions of three homogeneous antibodies elicited by type III pneumococcal vaccine were determined. All three antibodies had the group a allotype a1. Two of the antibody H chains (3374, 3381) had identical amino acid sequences in all framework positions that are considered correlates of the VH allotype, whereas the third H chain (3T72) differed from these at positions 15 and 16. The a1 allotypic specificities of the three homogeneous antibodies were compared by quantitative radiobinding and inhibition assays by using both insolubilized anti-a1 antisera and allotypic antiserum fractions rendered specific for the homogeneous antibody 3374. It was found that antibodies 3374 and 3381 are allotypically indistinguishable and have in common an a1 allotypic specificity that predominates in pooled a1 IgG. The allotypic specificity of the 3T72 antibody, on the other hand, was markedly deficient to those of 3374, 3381, and the a1 IgG pool. This correlation of allotypic difference with amino acid sequence variation at position 15 and 16 of the H chain indicates the involvement of these two residues in a major a1 allotypic determinant.
Radioimmunoassay of IgG and IgM Rheumatoid Factors Reacting with Human IgG
Authors: Carson Dennis A. , Lawrance Simon , Catalano Michael A. , Vaughan John H. , Abraham George 
Published: December 2022

Abstract
Although IgG rheumatoid factor may play a central role in the pathogenesis of rheumatoid arthritis, previously there have been no precise methods for its specific measurement in serum and synovial fluid. This paper describes a solid phase radioimmunoassay for the independent quantification of IgM and IgG rheumatoid factor reacting with the Fc fragment of human IgG. As measured by this assay, serum IgG rheumatoid factor levels differed significantly between patients with seropositive and seronegative rheumatoid arthritis and normal control subjects. In addition, several sera and joint fluids from patients with seropositive rheumatoid arthritis, even without vasculitis, were shown by gel chromatography to have acid-dissociable complexes of IgG rheumatoid factor suggestive of IgG-IgG dimer or trimer formation.
A New Method of Applying the Sips Equation
Authors: Nahm Moon H. , Herzenberg Leonard A. , Little Katharine , Little J. Russell 
Published: December 2022

Abstract
The Sips equation is frequently used in immunochemistry to describe the relationship between antibody-binding site concentration (no[Ab]), antigen concentration, intrinsic affinity constant (K), and the heterogeneity index (a) of the affinity constant. Usually no[Ab] is determined before calculating the remaining parameters (K and a). A new method is proposed which does not require knowledge of no[Ab] nor an extensive calculation to determine K and a. The method can also be used to determine the antibody-binding site concentration without purified antibody or ligand saturation of the binding sites. This method can be applied to any antibody which binds a monovalent ligand and which can be obtained at a concentration greater than 1/K. Since the Sips equation can be applied to any ordinary chemical reaction by setting a = 1, the proposed method can be used generally to determine the affinity constant and the initial concentration of one of the reactants.
Failure of B Lymphocytes in Human Blood to Regenerate Surface Immunoglobulin after its Removal by Antibody
Authors: Ault Kenneth A. , Unanue Emil R. 
Published: December 2022

Abstract
In culture, human blood B cells regenerated surface IgM and IgD after their removal by a brief treatment with pronase. In contrast, surface Ig was poorly reexpressed after interaction with specific antibody. Both classes of surface Ig were suppressed after treatment with antibody specific for only one. B lymphocytes from spleen and tonsils regenerated surface Ig after treatment with either pronase or anti-Ig. We suggest that the particular sensitivity of circulating B cells to anti-Ig-surface Ig interaction may be reflection of their state of maturation.
Studies on the Nature of the Relationship Between Ia Antigens and Fc Receptors on Murine B Lymphocytes
Authors: Dickler Howard B. , Kubicek Mary T. , Arbeit Robert D. , Sharrow Susan O. 
Published: December 2022

Abstract
Possible mechanisms for the specific inhibition by anti-Ia antibody of the binding of Ig complexes to B lymphocyte Fc receptors were evaluated. Capping of B cell Fc receptors did not lead to redistribution of antigens determined by genes in the I region or the I-A or I-C, I-E subregions as analyzed by indirect fluorescence and visual microscopy. In addition, the amounts of these antigens which could be quantitatively detected with indirect fluorescence and flow microfluorometry were unaltered by capping of Fc receptors. Thus, Ia antigens and B lymphocyte Fc receptors do not appear to be identical.
Quantitation of Ia antigens after binding of Ig complexes to B cell Fc receptors under noncapping conditions revealed partial (6 to 10%) inhibition of detection of antigens determined by genes in the whole I region but no inhibition of I-A or I-C, I-E subregion antigens. Thus, the majority of Ia antigens do not, in the native state, appear to lie in close physical proximity to B cell Fc receptors.
In view of the fact that the Fc portion of anti-Ia antibodies is not required to produce inhibition of binding to B cell Fc receptors, these observations suggest that this inhibition is due to a ligand-induced alteration of Ia antigens which leads to an interaction with the Fc receptors of B lymphocytes. Such Ia antigen-Fc receptor interactions may play a role in B cell activation.
Murine Plasma Cells Secreting More Than One Class of Immunoglobulin Heavy Chain
Authors: Morse Herbert C. , Goode Julius H. , Rudikoff Stuart 
Published: December 2022

Abstract
The amino terminal sequences of the κ light chains from SAMM 368 IgG2b and IgA have been determined. The two chains belong to different κ subgroups as indicated by 10 amino acid differences among the first 23 residues. An additional three residue differences were demonstrated in the sequence including the first complementarity region. These results indicate that single cells of SAMM 368 produce two unique κ-chains.
Identification and Partial Purification of Two Synergistically Acting Helper Mediators in Human Mixed Leukocyte Culture Supernatants
Authors: Farrar John J. , Koopman William J. , Fuller-Bonar Janet 
Published: December 2022

Abstract
The present study was undertaken to fractionate and identify the stimulatory factors within the mixed leukocyte culture (MLC) supernatant which induce a 150- to 1000-fold increase in the in vitro plaque-forming cell (PFC) response of T cell-deficient normal mouse adherent spleen cells. G-75 Sephadex gel filtration of the allogeneic supernatant revealed three distinct peaks of helper activity which were designated helper peaks (HP) 1, 2, and 3. The m.w. estimates for the three components were: HP-1, 10 to 15,000 daltons; HP-2, 40 ≥ 77,000 daltons; and HP-3, 20 to 25,000 daltons. HP-1 and HP-2 were further investigated and found to contain minimal helper activity at their respective optimal concentrations when compared to the activity of the unfractionated supernatant. The two components did, however, exhibit the remarkable capacity to effect synergistically an almost complete restoration of the PFC response. Expression of the helper factor synergism was dependent on the absolute concentration of HP-1 in the cultures but relatively independent of the amount of HP-2. Furthermore, the capacity of HP-1 to synergize with HP-2 was also dependent on the introduction of HP-1 to the cultures during the first 20 hr of the incubation period, suggesting that this component was crucial to the initiation of the PFC response. The results suggest that HP-1 and HP-2 have distinct sites-of-action in the B cell activation pathway and that full expression of the PFC response is dependent on the lymphostimulatory events mediated by these two moieties.
No Direct Association between Ia Antigens and Fc Receptors on the B Cell Membrane
Authors: Wofsy Leon , McDevitt Hugh O. , Henry Claudia 
Published: December 2022

Abstract
The capping of Ia antigens does not induce redistribution of Fc receptors (FcR) on B lymphocytes. This rules out the possibility of a unidirectional association between Ia and FcR such as has been reported to link Ig and FcR. Iacapping was achieved with hapten-sandwich antibodies devoid of Fc regions: hapten-conjugated Fab anti-Ia followed by (Fab′)2 anti-hapten antibody. Three different immune complex systems were used to label FcR. With fluorescent double labeling, Ia and FcR were readily distinguished. The independent labeling and surface mobility of Ia and FcR are considered in connection with reports of the inhibition of FcR by anti-Ia antibodies.
Mediation of Macrophage Cytolytic and Phagocytic Activities by Antibodies of Different Classes and Class-Specific Fc-Receptors
Authors: Walker William S. 
Published: December 2022

Abstract
The classes of antibodies that mediate the phagocytosis and cytolysis of 51Cr-labeled chicken erythrocytes by IC-21 macrophages, an established line of mouse peritoneal macrophages, were identified. The phagocytic activity of IC-21 macrophages, as determined by a functional inhibition assay with mouse myeloma proteins, depended mainly on IgM and IgG2a antibodies and to a lesser extent on IgG2b antibodies. Extracellular cytolysis of target cells was mediated solely by IgG2b antibodies. These results correlate with the previously documented specificities of discrete Fc-receptors for IgG2a and IgG2b immunoglobulins on IC-21 cells. Thus, phagocytosis and cytolysis appear to be mediated by antibodies of different classes operating through separate and distinct sites on the surface of IC-21 macrophages.
Expression of Thymocyte Surface Alloantigens in the Fetal Mouse Thymus in vivo and in Organ Culture
Authors: Kamarck Michael E. , Gottlieb Paul D. 
Published: December 2022

Abstract
Cell proliferation and surface alloantigen expression were monitored during development of the fetal mouse thymus in vivo from day 13 of gestation until birth, and in organ cultures established at day 13 of gestation. Expression of Thy-1, Ly-1, Ly-2, Ly-3, TL, GIX, and H-2b determined alloantigens was assessed with specific antisera in one- and two-stage complement-dependent microcytotoxicity assays. A series of C57BL/6-congenic strains was employed to control for effects of the genetic background. Results indicate that at day 13 of gestation alloantigen expression is too low for detection by the cytotoxic assay. From day 14 until birth, exponential cell proliferation is accompanied by gradual increase in alloantigen expression, and by day 19, Ly-1, Ly-2, Ly-3, Thy-1, and GIX are expressed at adult levels, whereas TL expression is higher and H-2b expression is lower than is seen in the adult thymus. In fetal thymus organ cultures established at day 13 of gestation, cell proliferation was not so extensive as was seen in vivo, and by 6 to 8 days in culture, Thy-1 was expressed on essentially all the cells. The other alloantigens were detectable on only 30 to 45% of the cells. Both in vivo and in vitro, the Ly-1, Ly-2, and Ly-3 alloantigens appeared simultaneously on the same population of thymocytes. Results are compared with the reported kinetics of alloantigen expression induced in prothymocytes upon exposure to thymopoietin.
Abrogation of Resistance to Foreign Bone Marrow Grafts by Carrageenans
Authors: Cudkowicz Gustavo , Yung Yee Pang 
Published: December 2022

Abstract
Natural resistance of mice to transplants of foreign bone marrow or leukemia cells is mediated by radioresistant non-T effectors which may interact with accessory macrophage-like cells sensitive to the toxicity of silica particles. The role of the accessory cells was reinvestigated by means of the soluble antimacrophage agent Seakem-9 carrageenan, and for comparison with silica particles. The agents abrogated or weakened resistance to parental, allogeneic, and xenogeneic rat marrow grafts when a single relatively small dose (2 mg/mouse or less) was injected intravenously into irradiated mice, 5 to 24 hr after transplantation. This effect was dose dependent, not influenced by the sex of recipients and donors and, unlike the effect of silica particles, not prevented by the previous injection into the mice of the lysosomal stabilizer (i.e., macrophage protector) poly-2-vinylpyridine N-oxide. This discrepancy raised the possibility that carrageenan weakened resistance by impairing the function of cells other than macrophages, whereas silica particles did so by way of selective macrophage depletion. However, the combined effect of suboptimal doses of carrageenan and silica particles was additive, a result which favors the view that carrageenan functioned as an anti-macrophage agent in vivo. These experiments reiterate the importance of macrophage-like cells interacting with radioresistant non-T cells (presumably null lymphocytes) in the development of natural cell-mediated responses such as resistance to hemopoietic grafts and generation of killer cells for certain lymphomas.
Target Cell-Substratum Interaction
Authors: David Gary S. , Wiglesworth Charlotte M. 
Published: December 2022

Abstract
When trypsinized cells were treated with alloantibody and complement they initially adhered to their substratum, then detached. Specific cytolysis did not occur. In addition to demonstrating an immunologically mediated reaction, this phenomenon has permitted the development of a new, simple, rapid assay for alloantibody that does not require a cytolytic reaction.
Immunologic Properties of Protein-Lipopolysaccharide Complexes
Authors: Scibienski R. J. , Gershwin M. E. 
Published: December 2022

Abstract
The in vivo antibody response to the lysozyme component of a lysozyme-lipopolysaccharide complex has been investigated in normal, thymectomized and nude mice. The splenic PFC response elicited by the complex in CBA mice is 10- to 20-fold higher than the response elicited by lysozyme admixed with LPS. Both lysozyme-LPS complexes and lysozyme + LPS mixtures prime mice for a subsequent secondary anti-lysozyme response. In contrast, thymectomized mice responded poorly to lysozyme-LPS complexes unless reconstituted with splenic T cells. However, nude mice responded as well as Nu/+ controls to the complex. The PFC response of normal and of nude mice was severely depressed by treatment with anti-lymphocyte serum. These findings suggest that T lymphocytes contribute significantly to the enhanced immune responsiveness associated with LPS administration.
Allotype Suppression in Rabbits: The Requirement for CH3 Domain of Anti-Allotype Antibody
Authors: Connell George E. , Dubiski Stanislaw 
Published: December 2022

Abstract
Facb fragments of rabbit anti-allotype antibody were prepared by plasmin digestion and isolated by gel chromatography. The antibody preparation was used in an attempt to induce allotype suppression in newborn rabbits. The Facb fragments were found to be ineffective in inducing the allotype suppression. Administration of Facb fragments caused a “burst” of immunoglobulin synthesis almost immediately after the administration of the antibody. It was concluded that the CH3 domain, which is responsible for the cytophilic activity of the antibody, is essential in induction of allotype suppression.
The Amino Acid Sequence of a Human Immunoglobulin G3m(g) pFc′ Fragment
Authors: Michaelsen Terje E. , Frangione Blas , Franklin Edward C. 
Published: December 2022

Abstract
Amino acid sequence analysis of the pFc′ fragment obtained by pepsin digestion of an IgG3; G3m(g) human myeloma protein HER shows it to consist of 112 residues. It starts at position 334 (γ1 numbering), contains eight residues of the Cγ2 region, and the whole Cγ3 domain. Comparison with the sequence of γ1 shows five differences including an extra Met at 397. Each is accountable by a single base substitution. The sequence is identical to that of a G3m(b0) molecule except for the previously noted allotype related Tyr/Phe exchange at position 436. The high degree of homology (95%) among γ-chain subclasses suggests a recent diversification.
Activation of Human B Lymphocytes
Authors: Fauci Anthony S. , Pratt Karen R. , Whalen Gail 
Published: December 2022

Abstract
In vitro hydrocortisone in physiologic and pharmacologically attainable concentrations caused a marked enhancement of the PWM-induced PFC response of normal human peripheral blood B lymphocytes. This effect was seen only when hydrocortisone was added within the first 24 hr of culture and only when hydrocortisone and PWM were present together in cultures. Only suprapharmacologic concentrations of hydrocortisone (10-3 M) were capable of suppressing early B cell activation. Late stages of antibody production and secretion were resistant to suppression by even these extraordinarily high concentrations. Hydrocortisone did not replace the T cell requirement of PWM-induced PFC responses. A single dose of in vivo hydrocortisone (400 mg) to normal adult volunteers did not produce this enhancing effect when PFC responses were measured in vitro in the absence of hydrocortisone.
The data strongly suggest that the enhancing effect of hydrocortisone was due not to elimination of naturally occurring suppressor cells, but to a modulation of the triggering signal either directly on the B cell itself or via the balance of positive and negative T cell regulation of B cell activation.
Release of Slow Reacting Substance (SRS) from Rat Basophilic Leukemia (RBL-1) Cells
Authors: Jakschik Barbara A. , Kulczycki Anthony , MacDonald Hanna H. , Parker Charles W. 
Published: December 2022

Abstract
When rat basophilic leukemia (RBL-1) cells were exposed to the ionophore A23187, a substance was released that produced a prolonged contraction of guinea pig ileum resembling that seen with slow reacting substances (SRSs) from various sources. The response was temperature, dose, and the time dependent with no activity being demonstrated in unstimulated cells. Several lines of evidence indicated that the RBL-1 product was markedly similar or identical to SRSs obtained from non-neoplastic tissues: 1) appropriate behavior in seven different chromatographic systems, 2) an appropriate profile of activity on various smooth muscle preparations, 3) an ability of low concentrations of the selective SRS inhibitor FPL 55712 to block the guinea pig ileal response, 4) failure of chymotrypsin to destroy activity, 5) loss of the activity after incubation with arylsulfatase, and 6) an ability to release activity from cells preincubated with indomethacin. Since RBL-1 cells can be grown in considerable quantity and under optimal conditions an average of 1500 SRS units/107 cells can be obtained, these cells should be useful as a biosynthetic source in further attempts to purify and characterize the SRS molecule.
Characterization of Effector Lymphocytes Associated with Immunity to Murine Sarcoma Virus (MSV)-Induced Tumors
Authors: Plata Fernando , Jongeneel C. Victor 
Published: December 2022

Abstract
Cytolytic T lymphocytes (CTL) and specific CTL precursor cells can be generated during the immune response to syngeneic tumors induced by murine sarcoma virus (MSV) in the mouse. MSV-immune spleen cells yield high numbers of specific CTL after incubation in vitro with irradiated tumor cells in syngeneic secondary mixed leukocyte-tumor cell cultures (sec-MLTC). Peak cytolytic activity generated in sec-MLTC is detectable on day 7 after culture initiation and decreases slowly thereafter. This report presents data showing that highly active CTL could be regenerated upon tertiary stimulation of long-term sec-MLTC with irradiated tumor cells bearing MSV-associated antigens. CTL activity recovered from tertiary MLTC could be detected in a short-term (3 hr) 51Cr release assay, and increased levels of cytolysis were already evident 24 hr after culture re-initiation. It was also shown that cells recovered from MLTC 12 days after tertiary restimulation could be further stimulated by specific tumor antigen in quaternary MLTC to yield increased CTL numbers. These results thus indicated that T lymphocytes could be repeatedly stimulated by specific tumor antigen in syngeneic MLTC to yield increasing numbers of cytolytic cells. Furthermore, the tumor antigen used for the initial stimulation of MSV-immune spleen cells in sec-MLTC appeared to have induced a specific selection of CTL precursor cells, since only syngeneic tumor cells bearing MSV-associated antigens were capable of inducing high levels of CTL regeneration in tertiary MLTC.
Serum Amyloid A (SAA) Protein — Interaction with Itself and Serum Albumin
Authors: Rosenthal C. Julian , Franklin Edward C. 
Published: December 2022

Abstract
Serum amyloid A (SAA) protein is a 12,000 dalton protein that exists in serum under physiologic conditions as an 85,000 dalton complex and under certain conditions, as a 170,000 dalton component. To study the reason for this finding, the behavior of 125I-SAA was studied in the presence of cold SAA and several serum proteins. SAA caused a shift of some of the radioactivity to the region of albumin. Addition of normal human serum or albumin caused a shift of a significant fraction of the radioactivity to a peak eluting slightly ahead of albumin (80,000 daltons). This interaction could be blocked by the addition of cold SAA. No shift was noted when IgG or Bence Jones proteins were added. Thus, it appears that low molecular SAA protein has a tendency to aggregate with itself and to bind to albumin but not to human IgG or Bence Jones proteins.
The Nature of Immune Complexes in Human Cancer Sera
Authors: Theofilopoulos Argyrios N. , Andrews Brian S. , Urist Marshall M. , Morton Donald L. , Dixon Frank J. 
Published: December 2022

Abstract
Sera from 517 patients with various types of malignancies were assayed for immune complexes (ICs) by the Raji cell radioimmune assay. The incidence of immune complexes in these patients ranged from 16 to 52% as compared to 19% in normal controls. Increases in tumor mass and metastatic disease were associated with high levels of circulating ICs. Immunization of melanoma patients with BCG and tumor-cell vaccine produced an increase in levels of ICs. Cancer sera contained complexes of intermediate size. Tumor antigens and IgG, presumably in the form of complexes, were identified by immunofluorescence and radiolabeled antibody techniques on the surface of Raji cells incubated in ICs-containing cancer sera.