bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regulation of the Immune Response to Tumor Antigens
Authors: Fujimoto Shigeyoshi , Greene Mark I. , Sehon Alec H. 
Published: December 2022

Abstract
A/Jax mice were rendered immune to the syngeneic and transplantable methylcholanthrene-induced Sarcoma 1509a by the surgical removal of the tumor 7 days after implantation; subsequent injection of tumor cells resulted in their rejection within 15 days.
The i.v. transfer of 107 to 108 washed thymus or spleen cells of tumor-bearing animals (TBA) to immune animals significantly inhibited the rejection of the tumor; this suppressive effect was entirely abolished by the treatment of these lymphocytes with anti-θ serum or anti-thymocyte serum (ATS) and complement before adoptive transfer. On the other hand, an equal number of thymus or spleen cells of normal animals or of animals bearing an unrelated tumor had no suppressive effect.
Treatment of normal syngeneic animals with ATS after tumor cell inoculation or splenectomy of TBA resulted in the suppression of the tumor growth. The serum of TBA had no effect on tumor growth in immune syngeneic mice.
Together these results suggest that TBA possess immunosuppressor T cells regulating negatively their immune response to the tumor.
Analysis of the Humoral Immune Response to Influenza Virus in Vitro
Authors: Braciale T. J. , Gerhard W. , Klinman N. R. 
Published: December 2022

Abstract
The induction of in vitro primary and secondary humoral immune responses to influenza virus in murine splenic explant culture is described. Anti-influenza antibody synthesized in vitro was detected and quantitated by a radioimmunoassay which utilized influenza coupled to bromoacetylcellulose. Both in vitro primary and secondary responses could be stimulated over a large range of virus doses. In vitro secondary responses were maximal when spleen donors had been immunized by the parenteral route although secondary type responses could be demonstrated as well after primary immunization by pulmonary infection. In vitro stimulation with influenza virus was relatively insensitive to inhibition at high antigen doses. The results are discussed in terms of the response to other antigens in spleen fragment culture.
Antibody-Induced Ultrastructural Changes of Malarial Sporozoites
Authors: Cochrane Alan H. , Aikawa Masamichi , Jeng Miji , Nussenzweig Ruth S. 
Published: December 2022

Abstract
Immunization with irradiated sporozoites produces a considerable degree of protection against rodent, simian, and human malaria. This protection is in part antibody mediated. Antibodies neutralize sporozoites (SNA), i.e., abolish their infectivity, and cause, in vitro, the formation of a thread-like precipitate on the parasites (CSP reaction). The present study was undertaken to characterize the ultrastructural aspects of antibody-sporozoite interaction. Gradient concentrated sporozoites of Plasmodium berghei and Plasmodium cynomolgi were incubated with immune and normal sera. Transmission electron microscopy revealed the presence of a prominent, thick coat surrounding the outer membrane of the sporozoites incubated in immune serum. The inner structure of these parasites appeared to be relatively unaltered. The coat was absent or minimal on parasites incubated in normal serum. Incubation of immune serum-pretreated sporozoites with rabbit anti-mouse γ-globulin conjugated with hemocyanin demonstrated the participation of immunglobulin in the formation of this surface deposition. Coat formation occurred also on the surface of metabolically inactive, non-secreting parasites such as formalin-treated sporozoites and parasites kept on ice. Metabolically inactive sporozoites failed, however, to produce a positive CSP reaction. Scanning electron microscopy and negative staining indicated that the anterior end of the parasites was free of coat deposition and that the thread-like precipitate (CSP) was located at the posterior end of the sporozoites.
Blocking of Certain Antigenic Sites in the F(ab) Region by Combination of Univalent Fragments of Rh Antibodies with Red Cell Antigens
Authors: Kunkel H. G. , Joslin F. , Hurley J. 
Published: December 2022

Abstract
Evidence was obtained in the present study substantiating the fact that divalent Rh antibodies are bound to antigenic sites on the red cells through only one of the two combining sites. Univalent F(ab) fragments bound to the red cell lacked such free-combining sites and showed a blockage of various idiotypic-like antigens which were readily detected when divalent antibodies or divalent fragments were used. The univalent fragments contained the antigens because they completely inhibited the divalent system. These antigens were detected with idiotypic antisera made to a variety of monoclonal Ig through the use of certain very heterogeneous anti-Rh sera. As is the case with many other idiotypic systems, combination with antigen which blocked the antibody-combining site eliminated the reactivity.
Advantage was taken of these differences between divalent and univalent antibodies to determine antigens in the F(ab) portion of Rh antibodies which are or are not blocked by such combination with the red cell. A variety of subclass and genetic markers found in the constant regions of the F(ab) units were not affected. However, in addition to the idiotype-related antigens a series of V region markers, particularly those determining various V region subgroups, were not detected after combination.
Defining the Heterogeneity of Anti-Tumor Antibody Responses
Authors: Segal Gary P. , Klinman Norman R. 
Published: December 2022

Abstract
Studies were undertaken to analyze the humoral in vivo and in vitro antibody response of BALB/c mice to a syngeneic MSV-induced tumor cell line. With a sensitive radioimmunoassay, sera obtained from individual progress or and regressor mice were shown to vary greatly in total tumor-specific antibody concentration as well as immunoglobulin class distribution of the antibody, but no significant difference existed between the groups of progressor and regressor mice as a whole. In addition, serum antibodies from all animals were shown to have extensive cross-reactivity against a variety of cell lines chosen to share one or more antigens with the cell line used for immunization. Conversely, when in vitro fragment cultures of splenic tissue from progress or and regressor mice were stimulated with tumor-related antigen, differences in responsiveness among normal, progressor, and regressor mice were observed. In addition, antibodies derived from fragment cultures displayed several different cross-reactivity patterns all of which were more restricted in specificity than serum antibodies.
Evolution of the Lymphoid System
Authors: Etlinger Howard M. , Hodgins Harold O. , Chiller Jacques M. 
Published: December 2022

Abstract
Leukocytes from the various lymphoid tissues of rainbow trout (RBT) were tested for their capacity to respond to the lymphocyte mitogens concanavalin A (Con A), lipopolysaccharide (LPS), and purified protein derivative of tuberculin (PPD). Thymocytes responded to Con A but not to LPS or PPD. In contrast, leukocytes from anterior kidney were stimulated with LPS but not with Con A or PPD. Cells from spleen and peripheral blood were stimulated by each mitogen. However, the degree of stimulation at optimally stimulatory concentrations of each mitogen was distinctive. The finding that the patterns of mitogenic responses of cells from each tissue were significantly different suggested that there is lymphoid heterogeneity in the RBT with a unique tissue distribution.
The species source of serum utilized as a medium supplement appeared to be capable of markedly affecting mitogenesis. Thus, LPS and PPD stimulation occurred in medium supplemented with rainbow trout serum (RBTS). On the other hand, LPS and PPD stimulation was not observed in medium supplemented with fetal bovine serum (FBS), with the exception of peripheral blood leukocytes which were stimulated by LPS in culture medium supplemented with FBS. Con A stimulated leukocytes from each lymphoid tissue in medium supplemented with RBTS and, with the exception of cells from anterior kidney, also stimulated cells from each tissue in medium supplemented with FBS.
The kinetic profiles of the responses of peripheral blood leukocytes to Con A, LPS, and PPD suggested that the extent as well as the time required for maximal stimulation was dependent on the dose of mitogen.
Enzyme-Linked Immunoassay: Conjugation of the Fab′ Fragment of Rabbit IgG with β-D-Galactosidase from E. Coli and its Use for Immunoassay
Authors: Kato Kanefusa , Fukui Hideo , Hamaguchi Yoshitaka , Ishikawa Eiji 
Published: December 2022

Abstract
A method for the conjugation of the Fab′ fragment of rabbit IgG with β-D-galactosidase from Escherichia coli is described. The method consists of two main steps: treatment of the Fab′ fragments containing sulfhydryl groups with excess N,N′-o-phenylenedimaleimide, to introduce maleimide residues into the fragments, and then incubation of the dimaleimide-treated Fab′ fragments with β-D-galactosidase, which also contains sulfhydryl groups, to form the rabbit Fab′-β-D-galactosidase complex. More than 90% of the enzyme used can be converted to the Fab′-enzyme complex, and the complex is readily separated from free Fab′ fragments by chromatography on a Sepharose 6B column. The application of the rabbit Fab′-β-D-galactosidase complex for immunoassay of macromolecular antigens is shown by measuring human IgG by the sandwich method. The rabbit (anti-human IgG) IgG-coupled Sepharose 4B is incubated with human IgG and then with the rabbit (anti-human IgG) Fab′-enzyme complex, and the enzyme activity bound to the Sepharose is measured. In this way it is possible to determine as little as 0.3 fmoles of human IgG.
Specific Selection of Cytotoxic Effector Cells: The Generation of Cytotoxic T Cells in Rat Thoracic Duct Lymphocyte Populations Positively or Negatively Selected for Reactivity to Specific Strong Histocompatibility Alloantigens
Authors: Wilson Darcy B. , Marshak Ann , Razzino-Pierson Giuliana , Howard Jonathan C. 
Published: December 2022

Abstract
These studies consider the generation of cytotoxic T lymphocytes (CTL) from precursors (CTLP) present in rat thoracic duct lymphocytes after stimulation with strong alloantigens. Also, they explore the relationship between CTLP and “initiator” (I) lymphocytes responsible for specific GVH and MLI reactions.
Positively selected TDL populations prepared in bulk MLI cultures show enriched GVH and MLI reactivity for the selecting major histocompatibility complex (MHC) haplotype, but no cytotoxic activity, raising the possibility that I and CTLP may belong to different subpopulations, and the latter failed to differentiate or to survive under these culture conditions. Restimulation of these cells in Marbrook culture vessels with the original priming haplotype under conditions suitable for generating killer cells in vitro resulted in greatly increased specific CTL activity with accelerated kinetics soon after priming and normal kinetics later. These findings indicate that “memory” killer cells can be generated in a previously stimulated lymphocyte population that had no overt cytotoxic activity. Restimulation with third party haplotypes failed to give CTL activity either to specific or to third party targets.
Negatively selected TDL populations prepared by “filtration” through x-irradiated F1 rats, depleted of specific GVH and MLI responses, were also depleted of the ability to generate CTL in Marbrook cultures stimulated with the selecting haplotype. Stimulation with third party haplotypes, or with both third party and specific haplotypes together, gave CTL effective only against the third party target.
Structural Requirements for Arthritogenicity of Peptidoglycans from Staphylococcus Aureus and Lactobacillus Plantarum and Analogous Synthetic Compounds
Authors: Kohashi Osamu , Pearson Carl M. , Watanabe Yoshiro , Kotani Shozo , Koga Toshitaka 
Published: December 2022

Abstract
The comparative studies on the arthritogenicity of chemically well defined peptidoglycans (PG)2 from the cell walls of Staphylococcus aureus (FDA 209P) and Lactobacillus plantarum (ATCC 8014) showed that 1) a polymer of disaccharide-peptide with or without the presence of N-acetylglucosaminyl-ribitol-teichoic acid produced severe arthritis; 2) oligosaccharide-peptides with or without the special structure (N-acetylglucosaminyl-ribitol-teichoic acid in S. Aureus, a polymer of rhamnose and glucose in L. plantarum) produced severe disease; 3) disaccharide-heptapeptide-disaccharide with or without the presence of either glucose-ribitol-teichoic acid or a polymer of rhamnose and glucose appeared to be arthritogenic but much less effective for disease production; 4) N-acetylmuramyl-heptapeptide-N-acetylmuramic acid and disaccharide-hexapeptide were non-arthritogenic; 5) none of the synthetic N-acetylmuramyl-peptides, including tetrapeptide, produced the disease. Thus it is concluded that arthritis-inducing activity is related to the peptidoglycan moiety but not to the special structure, and the most important moiety responsible for disease production may be located in a chain length of two or more disaccharide units on PG subunits. However, it is discussed that non-arthritogenicity of peptidoglycans, including synthetic compounds, may be due to a lack of adjuvanticity in rats rather than a lack of antigenic determinant(s) responsible for production of arthritis.
Complement and Macrophage Activation
Authors: Bianco C. , Eden A. , Cohn Z. A. 
Published: December 2022

Abstract
Activated mouse macrophages, obtained after i.p. injection of thiglycollate medium, bacterial endotoxin, and many other agents, behave differently from the resident peritoneal cells: they are present in higher numbers, they spread faster on surfaces, they have higher pinocytic rates, and they secrete a number of neutral proteases which are not detected in non-activated cells. Activated macrophages ingest sheep erythrocytes prepared with IgM and complement (EIgMC) whereas non-activated macrophages only bind these sensitized erythrocytes.
Experiments aimed at identifying the several roles played by complement in the process of macrophage activation were performed both in vivo and in vitro.
The increase in cell number, the ability to spread, and the capacity to ingest EIgMC after the injection of thioglycollate medium and endotoxin were not observed in mice pretreated with cobra venom factor.
Fresh mouse serum incubated with inulin, zymosan or cobra venom factor, when added in vitro to recently explanted normal macrophages, induces marked changes of cell shape: increased membrane ruffling, appearance of microspikes and intense spreading which peaks after 1 hr at 37°C.
Interactions of Human C1̄ with C-Reactive Protein and Polyanion-Polycation Complexes
Authors: Claus D. R. , Siegel J. , Gewurz H. 
Published: December 2022

Abstract
C-reactive protein (CRP) is a potent activator of the classical C pathway when reacting with C-polysaccharide (CPS), choline phosphatides and certain polycations. Using a C1̄ binding assay we have shown that, like IgG, native CRP can bind purified human C1̄. This binding was increased approximately 10-fold when CRP was aggregated by heat or bis-diazotized benzidine treatment or when CRP was combined with its substrates including CPS and protamine sulfate. Human C1̄ was found to bind to and transfer from CPS-sensitized E pretreated with CRP (E-CPS-CRP) as well as with anti-CPS (rabbit) IgG, indicating that this interaction involved the C1̄ macromolecule, and suggesting participation of C1q; agglutination of E-CPS-CRP by purified C1q supported this conclusion. In agreement with earlier experiments performed in whole serum, interaction of polyanions (e.g., heparin) and polycations (e.g., protamine and poly-l-lysine) resulted in substantial C1̄ binding independent of the presence of immunoglobulins. This was quantitatively increased in the presence of CRP, and CRP markedly enhanced C consumption induced by interaction of these counterions in whole serum, suggesting that CRP may have an important role in C consumption by polyanion-polycation complexes.
Factor B on Lymphoid Cells
Authors: Halbwachs Lise , Lachmann P. J. , McConnell I. 
Published: December 2022

Abstract
When Cobra venom factor (CVF) is added to suspensions of well washed lymphoid cells, an enzyme is generated which will cleave C3 in normal human EDTA plasma.
The generation of this C3 convertase requires Mg++. Factor D enhances the reaction but is not necessary for it to occur. The effect is due to the anti-complementary factor in CVF and not to contaminating phospholipase A, as heating the CVF at 70°C abolishes activity. The lymphocytes are therefore supplying the activity of Factor B in the generation of the enzyme.
Normal peripheral blood lymphocytes, chronic lymphatic leukemic cells, and five lines of cells derived from Burkitt's lymphoma patients all show the Factor B activity; erythrocytes and thymus cells do not. The amount of C3-cleaving activity generated increases with cell number but at least 108 cells/ml EDTA plasma are needed to show an effect.
The C3 convertase formed by adding CVF to lymphoid cells elutes spontaneously from the cells.
Mesangiocapillary Glomerulonephritis: Some Correlations Between Ultrastructure and Complement Profiles
Authors: Swainson C. P. , Kay A. B. 
Published: December 2022

Abstract
Mesangiocapillary glomerulonephritis has characteristic structural features. Some patients have persistently low serum concentration of C3 with the presence of a C3 nephritic factor (C3 Nef). In the present report, 40 adult patients have been studied and the ultrastructural and immunofluorescent appearances of renal biopsies correlated with serum complement profiles.
On electron microscopy 22 patients showed “dense deposits” in the glomerular basement membrane and the remainder subendothelial deposits. Complement abnormalities were found in the serum of 10 out of 23 patients studied, 9 of whom had “dense deposit” disease. All had C3 Nef and low values of C3, and 5 had low values of C6 and C7. Two of these patients also had low C1q and C4 concentrations. C3 Nef was measured by crossed over immunoelectrophoresis and by disappearance of the B antigen on C3. There was a highly significant correlation between the two techniques.
Subunit Structure and Properties of Human C8
Authors: Kolb W. P. , Morgan W. T. , Müller-Eberhard H. J. 
Published: December 2022

Abstract
Studies of C8 subunit structure and conformation may provide important clues concerning the role of C8 in the formation of a transmembrane channel by the C5b-9 complex. Human C8, when examined by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis under reducing conditions, is composed of three polypeptide chains with the following molecular weights: α, 77,000; β, 63,000; and γ, 13,700. When using SDS and urea in the absence of reducing agents, two subunits are visualized: α-γ, 99,000 daltons, and β, 75,000 daltons. The α-chain appears to be largely concealed in the interior of the C8 molecule. This conclusion was deduced from the differential distribution of 125I after labeling of C8 by the chloramine-T method, either in its native form or under conditions which cause unfolding and dissociation into subunits. Whereas the β- and γ-chains take up 125I in proportion to their mass, the α-chain remains totally unlabeled in the native molecule.
Changes of the Complement Profile and Occurrence of Complement Breakdown Products After the Injection of Inulin or agg-IgG in Baboons
Authors: Lambert P.-H. , Houba V. , Perrin L. H. , Machnik F. 
Published: December 2022

Abstract
The interpretation of the complement profile in various clinical situations is often a difficult problem. In order to better define the changes occurring in vivo after the activation of the classical or of the alternative pathway, 13 baboons were injected either with aggregated human IgG (agg-IgG, 10 mg/kg) or with inulin (20 mg/kg) and plasma samples were collected serially. The following observations were made: 1) 4 hr after inulin or agg-IgG, C3 levels decrease to a minimum of 79 and 80% of the initial value, respectively. Native C3 antigen is decreasing faster than C antigen. 2) C1q remains constant in both experimental groups. C4 decreases to 84% 1 hr after Agg-IgG, then is normalized whereas, after inulin, it remains unchanged during 4 hr then strikingly increases to 188% after 24 hr. 3) Properdin decreases to 86% 1 hr after agg-IgG and to 79% 2 hr after inulin.
EAC14 and EAC4 Preparation with a Magnesium-binding Chelator, and SAC4 Inactivation by a Factor in Normal Serum
Authors: Linscott W. D. 
Published: December 2022

Abstract
Improvements have been made in the use of triethylenetetramine hexaacetic acid (TTHA), a strong chelator of Mg++ but not of Ca++, such that highly active EAC14 and EAC4 can be prepared by incubation of EA with TTHA-serum. It is essential to use a low ionic strenth, a long incubation period at 0°C, and to maintain a low pH (5.8) to avoid C3 contamination. The resulting cells are appreciably more active with limiting C2 than are cells prepared by the EAC1 plus EDTA-serum method, and stable to storage. IgG, IgM, and whole anti-Forssman antiserum all gave good preparations.
An unusual pH dependence was observed, in that SAC14 activity was generated between pH 5.6 and 7.0, and between pH 7.8 and 9.0, but not at pH 7.5. It was found that normal guinea pig serum contains a heat-stable factor which inactivates SAC4 at pH 7.5 in the presence of EDTA. This inactivation is such that there is a marked decrease in lysis with limiting C2, but no shortening of the Tmax.
Inhibition of Complement by a RNA Containing Extract Derived from Ehrlich Ascites Tumor Cells
Authors: Renk C. M. , Hoffman E. M. 
Published: December 2022

Abstract
Phosphate-buffered saline (PBS) extracts of whole Ehrlich ascites tumor cells (EATC) inhibit complement-mediated immune hemolysis. Attempts have been made to purify and characterize the active inhibitory factor in the tumor cell extracts. A combination of DEAE chromatography and phenol extraction yielded an inhibitory product that was approximately 80% RNA. Superior yields were obtained by direct phenol extraction of crude EATC extract followed by ethanol precipitation.
Phenol extracts of EATC material inhibited EAC1̄ and EAC1̄4. There was no effect on any of the other complement component intermediate complexes. EAC1̄ treated with the phenol extract were effectively inactivated in 15 min at 30°C. There was no inactivation of fluid phase C1̄ under the above conditions, but significant fluid phase C1̄ consumption was seen after longer incubation periods. In addition, phenol extracts of EATC precipitated with C1q after 2 days' incubation. Sucrose density gradient results indicated that the EATC RNA was heterogenous with respect to size, and it was more effective as an inhibitor than was RNA from other sources.