bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cytotoxic Effect of Normal Human Sera on Murine Lymphoma (EL4) Cells. Evidence for a Role of Activation of Complement System
Authors: Kuo Chao-Ying 
Published: January 2023

Abstract
Normal human sera have been shown to kill murine target cells, including both normal lymphoid and tumoral cells. In this study, the evidence of activation of complement system for this heterocytotoxicity is presented. Chemical carcinogen-induced EL4 lymphoma cells were used as target cells. The EL4 cells were obtained either from the ascitic fluid of tumorous mice or from tissue culture. The cytotoxicity of human serum was determined by microscopic examination of viability of target cells after incubation with serum samples. Viable cells were determined by exclusion of trypan blue dye. The hemolytic activity of serum complement was quantitated by microtiter plate assay with EA cells.
The evidence for the activation of complement system responsible for the heterocytotoxicity of human serum to EL4 cell was obtained from decomplementary experiments. 1) Both the cytotoxic effect and hemolytic activity of human serum was totally abolished after heating at 56°C for 30 min.
Analysis of the Mechanism of VSV Inactivation by Human Serum
Authors: Mills B. J. , Cooper N. R. 
Published: January 2023

Abstract
Vesicular stomatitis virus (VSV), a mammalian RNA virus enclosed by a lipid bilayer membrane of host cell origin, is inactivated by normal human serum. Several possible mechanisms of this inactivation were examined. 1) Neutralization by antibody alone. This possibility was ruled out by showing that virtually all (&gt;90%) of the neutralizing activity was lost after heating the sera. Also most preparations of human IgG, IgA, or IgM failed to neutralize VSV. 2) Neutralization by a combination of low levels of antibody together with complement. Anticellular antibody is unlikely since human sera effectively neutralized VSV grown in cell lines from multiple species even after absorption with uninfected cells in which the virus had been grown. Similarly, anti-viral antibody appears unlikely since normal human serum effectively neutralized after absorption with cells expressing VSV antigens. Furthermore, purified human IgG did not potentiate the neutralizing ability of normal serum.
Effect of Lipids on the Cytolytic Action of Complement (C)
Authors: Ohanian Sarkis H. , Schlager Seymour I. , Borsos Tibor 
Published: January 2023

Abstract
Several recent reports raised the possibility that the target for the action of C (particularly the late acting components) in the cell membrane may be lipids or phospholipids. We have postulated that under certain conditions (e.g., after partial activation) C action could be inhibited by lipids found in cell membranes. The following lipids were tested: phosphatidyl glycerol (PG), cardiolipin (CL), cholesteryl esters (CE), phosphatidyl serine (PS), phosphatidyl ethanolamine mammalian (PEm) or bacterial (PEb), sphingomyelin (SP), cholesterol (CH), triglyceride, or phosphatidic acid. Lipids were mixed into VBS-gelatin and sonicated until a stable suspension was obtained. From dose response and kinetic studies we determined that about 10 min incubation of C at 0°C with 30 µg of lipids was appropriate for screening for inhibiting activity. The following pattern of inhibition of lysis emerged: 1) lysis of EA by limiting HuC and GPC: human C, no inhibition; GPC: whole C and C1̄ by PG only; C8, C9, no inhibition.
The Structural C6 Polymorphism: Nonlinkage Between C6 and Chromosome 6 Marker Loci
Authors: Olving J. H. , Olaisen B. , Teisberg P. , Gedde-Dahl T. , Thorsby E. 
Published: January 2023

Abstract
The complement factor 6 polymorphism has been examined in a Norwegian family material by two techniques: either high voltage agarose gel electrophoresis or isoelectric focusing in polyacrylamide gel slabs. Proteins with C6 activity were visualized by a specific, hemolytic assay. Agarose electrophoresis gave good separation of common allele products and easy discrimination between the common C6 types: C6A, C6AB, and C6B. Prolonged isoelectrofocusing gave better band separation, but the discrimination between the common C6 types is not noticeably better than with the agarose technique. For detection of rare alleles isoelectrofocusing is presumably the method of choice.
In a Norwegian population sample, C6 gene frequencies were: C6A: 0.61 and C6B: 0.39.
The data on the linkage relationship between the HLA region loci and C6 show that C6 complement locus is not within measurable distance to the HLA region. Linkage studies also indicate nonlinkage between C6 and another chromosome 6 marker locus, PGM3. C6 has therefore been excluded from a substantial portion of the short arm of chromosome 6.
Interaction Between Lymphocytes and Fluid Phase Murine and Human C3b
Authors: Papamichail M. , Pepys M. B. 
Published: January 2023

Abstract
C3 participates in lymphocyte cooperation leading to antibody formation and in antigen-localization by germinal centers. These functions probably involve the adherence of fixed C3b to complement receptors on lymphocytes and possibly macrophages. During investigation of the role of C3 in antibody formation in human and murine in vitro culture systems, the interaction of purified fluid phase C3b with lymphocyte complement receptors was studied by immunofluorescence. Human peripheral blood and tonsil complement receptor lymphocytes (CRL) were stained by incubation with human or murine C3b followed by specific F(ab)2 anti C3-FITC. Murine CRL failed to stain with these same reagents, despite the fact that murine C3b blocked formation of complement-dependent rosettes. Binding of mouse C3b to murine CRL was directly demonstrated using C3b itself labeled with fluorescein and could be blocked by unlabeled mouse C3b. It affected the same cells as formed C3-dependent rosettes, none of which were T lymphocytes.
Stable Evolutionary Conservation of Complement-Activating and Related Pentagonal Serum Proteins: C-reactive Protein and Protein SAP
Authors: Pepys M. B. , Dash A. C. , Richardson N. , Munn E. A. , Feinstein A. , Fletcher Thelma C. 
Published: January 2023

Abstract
Human CRP efficiently activates the classical complement pathway via C1q. Protein SAP (amyloid P-component) is a normal plasma protein which resembles CRP structurally, but differs in not being an actue phase reactant. Both proteins can interact with cell membranes but their in vivo functions are not known; they are presumably important since, as we now report for the first time, very similar molecules are also present in the sera of diverse species including elasmobranchs, teleosts, amphibia, birds and non-primate mammals. CRP and protein SAP were isolated by calcium-dependent affinity chromatography on insolubilised pneumococcal C-polysaccharide and agarose respectively, followed by gel filtration. The different proteins all had pentagonal disc-like molecules in the electron microscope and there were marked similarities between the CRP and SAP of such diverse species as the plaice and man. The pure proteins each yielded homogeneous subunits in SDS-PAGE with molecular weights of between 20–30,000 in different species.
A New “Inhibitor” of Complement (C5)-Derived Chemotactic Activity
Authors: Daniel Perez H. , Manning Donna , Lipton Mark , Goldstein Ira M. 
Published: January 2023

Abstract
In the course of examining polymorphonuclear leukocyte (PMN) chemotaxis in patients with systemic lupus erythematosus (SLE), we have found a previously undescribed serum “inhibitor” of complement (C5)-derived chemotactic activity. Serum from a 25-year-old Black female with untreated SLE, when activated with zymosan, failed completely to attract either her own or normal PMN (measured by the “leading front” method of Zigmond and Hirsch). Incubation of normal PMN with the patient's serum (PS) did not affect random motility or chemotaxis towards normal zymosan-treated serum (ZTS). Whereas levels of C3 were modestly low in PS, no gross abnormalities involving alternative complement pathway activation could be detected. Furthermore, treatment of PS with zymosan resulted in the generation of normal amounts of C5-derived PMN lysosomal enzyme releasing activity (attributable to “C5a”). Incubation of normal ZTS or column (Sephadex G-75)-purified “C5a” with PS did not affect lysosomal enzyme releasing activity but did result in a significant dose-dependent diminution of chemotactic activity.
SC5b-9: Regeneration of the Ability to Interact with Lipid by Selective Removal of the S-Protein
Authors: Podack E. R. , Halverson C. , Esser A. F. , Kolb W. P. , Müller-Eberhard H. J. 
Published: January 2023

Abstract
The various complexes were prepared by mixing isolated C5b-6 in the presence of detergents or phospholipids with equimolar amounts of C7, C7 and C8, or with C7, C8 and C9 in molar ratios of 1:1:1:3. C5b-9 was also prepared by treating the SC5b-9 complex purified from inulin activated serum with 6 mM Na deoxycholate (DOC) at pH 8.1 and subjecting it to gel filtration on Sepharose 6B in the presence of DOC. This treatment resulted in selective dissociation of the S-protein, in exchange for binding of DOC by C5b-9.
Detergent-binding studies showed that C5b-6, C5b-7 and C5b-8 bind 26, 28 and 65 mole 14C-DOC per mole of complex, respectively, as measured by equilibrium dialysis. C5b-9 (prepared from SC5b-9) binds 86 mole DOC per mole of complex, measured by gel filtration in the presence of 3H-DOC. DOC binding as well as cetyl trimethyl ammonium bromide (CTAB) binding of all complexes could also be demonstrated by charge shift electrophoresis.
Characterization of the Ss and S1p Genetic Variants of Mouse C4
Authors: Roos Maria H. , Atkinson John P. , Shreffler Donald C. 
Published: January 2023

Abstract
The genetic control of quantitative (Ss) and qualitative (S1p) variations in two closely related mouse serum proteins has been localized to the S region of the mouse major histocompatibility complex (H-2). These serum proteins were found to be immunochemically and probably functionally homologous to human C4. Further biochemical and genetic characterizations of the Ss and S1p proteins have been done by immunoprecipitation techniques. Adherent peritoneal exudate cells from mice of strain B10.W7R, which express both the Ss and the S1p proteins, were cultured in vitro in medium containing 14C-labeled amino acids. These cells synthesized both Ss and S1p, as revealed by immunoprecipitation with anti-Ss and anti-S1p from the 14C-labeled, 24 hr macrophage culture supernatant. After SDS solubilization and 2-ME-reduction of the precipitates and separation on an SDS polyacrylamide slab gel, autoradiography revealed three major bands of activity with each antiserum. With anti-Ss, these polypeptides had m.w. of 98,000, 75,000, and 33,500, comparable to the α β and γ chains of human C4.
Murine Factor B (Bf): Electrophoretic Polymorphism and Linkage to the H-2 Region
Authors: Rubinstein Pablo , Day Noorbibi K. 
Published: January 2023

Abstract
Mouse Bf measured by indirect lysis with glutathione-treated cells was shown to be present in high quantities in chemically induced mouse ascites fluid (MAF). Functional MAF Bf has physical properties identical to mouse serum Bf. It is heat labile, Mg++ dependent, and is activated by purified CVF. Purification was carried out with Bio-Rex 70, CM 32, and DE 52 column chromatography. The optimum isoelectric pH was previously determined by isoelectric focusing. Fractions for Bf were tested by immunochemical means by using cross-reacting goat antihuman Factor B and by functional assays. Antiserum to purified Bf was prepared in the goat. By immunoelectrophoresis and rocket electrophoresis MAF Bf and serum Bf migrated anodally. Cleavage of a cathodal migrating Bf fragment was observed with purified CVF. Bf phenotypes were typed by the immunofixation procedure. Sera from male and female mice of 16 inbred strains were examined (A/J, A.KR, CBA, C3H, B10.BR, C58, B10, B10.A, C57L, C57 BL/Ks, B10.D2, DBA/2, DBA/1, BALB/C, 129/J).
Nephritic Factor (TA): A Homogeneous Immunoglobulin Directed Toward the Complex of C3 and Factor B of Human Complement
Authors: Schreiber R. D. , Muller-Eberhard H. J. 
Published: January 2023

Abstract
Nephritic factor (NF) was isolated from serum T.A., NF(TA), as we have previously described, including selective binding to and decay-release. After two such cycles, 90% of the protein bound to compared to 2% specific binding of partially purified material consisting only of IgG. Purified NF(TA) did not bind to EC3b in absence of B and D, nor to C3bINA and β1H-treated EC3b in presence of B and D. The chain structure of NF was examined by SDS PAGE of the reduced protein after iodination using the chloramine-T (CT) or the Bolton Hunter (BH) method. According to the distribution of radioactivity, the subunit size of CT labeled NF was 60,000 daltons (92%) and the subunits of BH labeled NF were 60,000 (67%) and 25,000 daltons (33%). IgG iodinated by either method showed subunits of 52,000 (67%) and 25,000 daltons (33%).
Studies of a Polysaccharide in Ant Venom (Pseudomyrmex sp.) that Activates the Classical Complement (C) Pathway
Authors: Schultz D. R. , Arnold P. I. , Wu M-C , Volanakis J. E. 
Published: January 2023

Abstract
A polysaccharide (PS) from the venom of a tropical ant interacts with a human nonimmunoglobulin protein(s) in serum, causing C1 activation and the consumption of the functional activity of C4 and C2 (D. R. Schultz, P. I. Arnold, J. Immunol., in press). We now describe these studies in more detail.
The PS had a heterogeneous size in native ant venom. The smallest moiety that activated serum C1 had a m.w. of ca. 3,000 as determined by gel chromatography. The PS was not precipitated by barium salts, showing no apparent sulfate groups. The following sugars and the molar ratios were found by gas chromatography: mannose (7.7), fucose (1.8), N-acetylgalactosamine (1.6), galactose (1.4), glucose (1.0), and N-acetylglucosamine (1.0).
Evidence showing that a serum β-lipoprotein (B-LP) participates with venom PS to cause activation of C1 includes: 1) The PS caused a visible precipitation when incubated with normal human serum or its highly purified B-LP at 37°C for 12 hr.
The Immunoglobulin Nature of Nephritic Factor: NEF Activity Is Found in Fab and Fab′2 As well As in Intact IgG
Authors: Scott D. M. , Amos N. , Sissons J. G. P. , Peters D. K. 
Published: January 2023

Abstract
In earlier studies1 we were unable to separate Nephritic Factor (Nef) from IgG by a variety of immunochemical techniques, indicating that Nef shares antigenic determinants with IgG. Purified Nef was found to bind to Protein-A-Sepharose, and could be eluted with acid. This binding was complete in three samples of Nef from patients with PLD or MPGN, but only partial in the fourth.
We have now investigated the effects of pepsin and papain digestion on Nef structure and activity. Digestion of Nef with pepsin caused virtually no loss of activity. Before pepsin digestion this Nef preparation bound completely to Protein-A-Sepharose. After pepsin treatment 40 to 65% of the Nef was now recovered in the breakthrough peak and only 7% was eluted in the acid eluate. Digestion of Nef with papain caused some loss of activity. Approximately 30 to 80% of the activity was recovered.
Complement Metabolism in Sickle Cell Disease (SCD)
Authors: Sisson J. G. P. , Wilson W. A. , Thomas J. , Frampson G. 
Published: January 2023

Abstract
Individuals with homozygous Sickle Cell Disease (SCD) are prone to bacterial infection. SCD sera have previously been shown by others to have a defective capacity to opsonify pneumococci—this has been attributed to impaired alternative pathway function, which was postulated to be due to defective synthesis of factor B in such cases.
Sera from 100 cases of homozygous SCD have now been studied. There was reduced alternative pathway activity in one-third of sera (using a haemolytic plate assay dependent on Mg++ and agarose to activate the alternative pathway), and haemolytic factor B activity was significantly lower in this group than in the other sera. C3 concentrations were also reduced in one-third of sera.
The metabolism of purified radiolabeled factor B and C3 was studied in 12 cases to determine whether diminished synthesis or increased catabolism of these proteins occurred in SCD. Synthesis of B and C3 was normal or increased in all cases.
Utilization of Properdin in Children with Vasculitis and Milk Allergy
Authors: Spitzer R. E. , Stitzel A. E. , Urmson J. R. 
Published: January 2023

Abstract
Patients with various types of vasculitis, both nonspecific and that associated with more definitive syndromes such as Henoch Schönlein Purpura (anaphylactoid purpura), have serologic findings which indicate that properdin is consumed during disease activity. In all of 22 patients with documented Henoch Schönlein Purpura, the level of serum properdin was reduced more than three standard deviations below the mean in the first week of the disease. Those patients with predominant signs of abdominal pain and glomerulonephritis had more pronounced reductions in serum properdin than did those with arthritis as a presenting symptom. All other serum C components and alternative pathway proteins including C1–C9, factor B, and factor D were normal. Serum levels of properdin convertase were reduced in 12 of the 22 patients. As the disease subsided, levels of properdin and properdin convertase returned to normal. Properdin has also been found deposited in the glomerulus of these patients by immunofluorescent studies of renal biopsies.
Studies on the Liberation and Cleavage of Lipids from the Erythrocyte Membrane During Complement Lysis
Authors: Valet G. , Kahle H. , Scherer R. 
Published: January 2023

Abstract
Inoue et al. (J. Immunol. 116, 1737, 1976) and Shin et al. (Fed. Proc. 36, 1209, 1977) have reported that phosphatidylethanolamine (PE) and phosphatidylcholine (PC) are liberated from liposomes during C lysis. We have investigated if this occurs also in erythrocyte membranes. Radiolabeled PC, PE, glycerinetrioleate (TO), glycerinetripalmitate (TP), or free fatty acids (FFA) were incorporated in separate experiments into the membrane of sensitized (EA) and unsensitized (E) sheep erythrocytes by incubation at 4°C. After several washes with isotonic buffer, the erythrocytes were lyzed with distilled water. This procedure removed the nonmembrane-bound lipids from the exterior and interior of the cells. EA ghost membranes prepared in this way are still reactive to the C action (Valet et al., J. Immunol. 115, 1028, 1975). Half of the EA ghosts were incubated with fresh, and the other half with 56°C inactivated guinea pig serum for 2 to 5 min at 37°C.
Identification of C3 Nephritic Factor
Authors: Williams D. Gwyn 
Published: January 2023

Abstract
The serum from two patients—one with mesangiocapillary glomerulonephritis (MCGN) and one with partial lipodystrophy and MCGN-with C3 nephritic factor (C3NeF) was separated chromatographically on DEAE, CMS, and Sephadex G-200. In each case only IgG was detectable on double immunodiffusion in the final C3NeF-containing fractions. IgG from these fractions was adsorbed onto a CNBr-anti-IgG column, and on elution the IgG was shown to have C3NeF activity. Removal of IgG from the fractions by immunoadsorption with solidified monospecific anti-IgG resulted in removal of C3NeF activity. Analysis by double immunodiffusion of the IgG with C3NeF activity in each case showed it to contain more than one subclass of IgG, and that both κ- and λ-chains were present. It is concluded that in these two patients the C3NeF activity resided in nonrestricted IgG.
Activation of Phospholipid Metabolism During Mediator Release from Stimulated Rat Mast Cells
Authors: Kennerly Donald A. , Sullivan Timothy J. , Parker Charles W. 
Published: January 2023

Abstract
Phospholipid metabolism was studied during mediator release from highly purified rat mast cells. The incorporation of 32PO4 into individual phospholipids was determined after isolation of phospholipid classes by two-dimensional thin layer chromatography. Various stimulators of histamine release (anti-IgE antibody, concanavalin A [Con A], compound 48/80, or the ionophore A23187) increased 32PO4 incorporation into phosphatidic acid (PA), phosphatidylinositol (PI), and phosphatidylcholine (PC) 4- to 10-fold within 15 min. No change in 32PO4 incorporation into phosphatidylserine (PS), phosphatidylethanolamine, or sphingomyelin was detected. Anti-IgE antibody caused significantly increased labeling of PA within 8 sec and of PI and PC within 30 sec. The concentrations of anti-IgE and Con A causing threshold, half maximal, and maximal phospholipid labeling were slightly less than those required for comparable changes in histamine release. Both phospholipid labeling and mediator release in response to anti-IgE or Con A were enhanced 3- to 4-fold by PS. The addition of 50 mM α-methylmannoside to mast cells 10 min after challenge with Con A rapidly halted both ongoing mediator release and PA labeling. The results of these studies indicate that marked and selective changes in phospholipid metabolism occur before as well as during mediator release from mast cells and that these reactions may be an intrinsic part of the biochemical mechanisms that control mediator release.
Slow Reacting Substances: Comparison of Some Properties of Human Lung SRS-A and Two Distinct Fractions from Ionophore-Induced Rat Mononuclear Cell SRS
Authors: Bach Michael K. , Brashler John R. , Brooks Carter D. , Neerken A. John 
Published: January 2023

Abstract
When mononuclear cells from the peritoneal exudates of rats are challenged with the ionophore A 23187 they produce a slow reacting substance (SRSri), and production of this activity is markedly enhanced if 0.01 M L-cysteine is also added to the incubations. Previous work from this laboratory had shown that the properties of SRSri resembled those that had been described for slow reacting substance of anaphylaxis (SRS-A) in the literature. We have now directly compared SRSri to SRS-A generated immunologically in chopped human lung. A high performance liquid chromatography separation of SRSri on Florisil has been developed by using a linear gradient of water into methanol for elution. SRSri is completely resolved into two peaks of activity, comprising approximately 33 and 67% of the total activity. SRS-A elutes at a postion that is identical to that for the smaller of the SRSri peaks. Although both peaks of SRSri activity are stable to boiling in alkali and are destroyed upon boiling in 0.1 N HCl, there are quantitative differences in the rate of destruction of the two activities and of SRS-A. Similarly, the susceptibility of the three preparations to inactivation by sulfatase from Patella vulgata was different. In addition, inhibition of contractions caused by these three preparations by the end organ antagonist of SRS-A, FPL 55712, also suggested differences between the preparations. Thus, the results suggest the existence of a family of substances that, loosely, satisfy the criteria to be referred to as SRS-A, although they differ in certain details.