bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anti-Protein Plaque-Forming Cells Detected with High Efficiency by the Use of Red Cells Coupled to Bovine Serum Globulin through Bis-diazo-benzidine
Authors: Kapp Judith A. , Ingraham J. S. 
Published: December 2022

Abstract
It has been known for many years that sheep red cells coupled to proteins through diazotized benzidine can be hemolyzed by anti-protein sera (1). However, early attempts to use protein-coupled cells in the hemolytic plaque assay to detect cells producing anti-protein antibodies were unsuccessful (2). The first successful experiments were done with red cells coupled to protein by means of 1-ethyl-3-(3-dimethylamino propyl) carbodiimide HCl (ECDI) (3, 4), but this method has drawbacks in that ECDI is an expensive reagent, and large amounts of protein are required to obtain coupled cells with useful sensitivity.
We have now re-investigated the use of benzidine and have found that we can obtain sheep red cells coupled with bovine γ globulin (BGG-SRBC) which are more efficient in detecting anti-BGG plaque-forming cells (PFC) than were any of the preparations we obtained after detailed investigation of the ECDI technique (5).
Inhibition of Natural Cytotoxic Rabbit Antibody by Human IgM: Production of Nontoxic Rabbit Serum for Use As Complement Source
Authors: Herberman Ronald B. 
Published: December 2022

Abstract
A simple method for the production of nontoxic rabbit serum has been developed. Small amounts of human IgM completely inhibited the cytotoxic activity of the natural serum antibody in normal rabbit serum reactive with human cells. IgM from both normal human sera and from the sera of patients with Waldenström's macroglobulinemia had similar inhibitory activity. Macroglobulins from mouse and rabbit sera were inactive. The human IgM did not interfere with complement activity or with the activity of cytotoxic antibodies from other species.
Measurement of Rubella Antibody by Hemagglutination Inhibition
Authors: Liebhaber Harvey 
Published: December 2022

Abstract
A method employing dextran sulfate and CaCl2 (DS-C) for removing nonspecific inhibitors of rubella virus hemagglutinin from test sera has been described. Sera treated by this method were shown to be free of detectable inhibitor. No quantitative changes in IgG, IgA and IgM could be detected, nor was any qualitative change in IgG observed as a result of DS-C treatment. The hemagglutination-inhibition (HAI) test employing DS-C treated sera was shown to be a true measure of actual rubella antibody content, and 100% of the HAI titers determined on 47 paired sera were identical or equivalent (±1 dilution).
Kaolin by comparison was shown to be an unreliable means of specifically removing non-immunoglobulin inhibitors. Kaolin failed to remove inhibitors completely from many sera, and it sometimes removed specific antibody from others.
A modified heparin-MnCl2 procedure was found to give erratic and unreliable results. The basis for these undesirable characteristics of the heparin-MnCl2 method was explored and an improved heparin-MnCl2 procedure was tried. This procedure gives reproducible and reliable results, but has the disadvantage that it fails to remove all traces of inhibitor from some sera, thus giving rise to false positive tests.
Biosynthesis and Assembly of Immunoglobulin in Rabbit Lymph Node Cells
Authors: Moav Boaz , Harris T. N. 
Published: December 2022

Abstract
Antibody or γ globulin molecules synthesized within the cell or added to cell homogenates were found to be adsorbed and strongly bound to the ribosomes when these were subsequently extracted. Comparison of these proteins with others indicated that the extent of this binding could be affected by the pK of the protein. Measurements of the binding of γ globulin and light chains to ribosomes indicated that γ globulin has about 150 times as many binding sites/ribosome at saturation.
After a short pulse of 14C-amino acids, radioactive nascent peptides were removed from ribosomes by puromycin in a cell-free system. These peptides were largely of low moleculare wight, and adsorption on specific immunoadsorbents indicated the presence of heavy chain material but not of light chain determinants. These results suggest that assembly of rabbit IgG occurs between complete chains, and not by a combination of a complete light chain and a nascent heavy chain.
The Use of an Immunofluorescence Technique for the Determination of Antibodies to Cytomegalovirus Strains in Human Sera
Authors: Chiang Wen-Tsuo , Wentworth Berttina B. , Alexander E. Russell 
Published: December 2022

Abstract
An immunofluorescence technique was used to investigate antigenic heterogeneity among cytomegalovirus (CMV) strains. Twelve strains of human CMV were examined by titration with their homologous human sera. The strains were selected to reflect a range of geographic origin, site and year of recovery, age and clinical disease of the host. Antigens from CMV strains AD 169 and Davis, a simian CMV strain, herpes simplex and varicella-zoster (VZ) viruses were included. On the basis of this initial study, the human CMV strains studied appeared to fall into three groups. Two strains recovered in Taiwan formed one distinct group. Other strains from Taiwan, however, were not found to give the same reaction pattern, so the difference did not appear to be due strictly to geographic origin. UW-1 and UW-2 strains from neonatal infections and another Seattle strain from a case of recurrent parotitis constituted a second group. The remaining strains fell into an intermediate group, distinct from the Taiwan strains. No similar differentiation was found in complement-fixation (CF) tests with the same sera and antigens.
Human CMV strains did not appear to cross-react in the immunofluorescence test with other members of the herpesvirus group, including the CMV strain of simian origin. The specificity of this technique warrants its use as a diagnostic tool for virus identification, since most of the human CMV strains employed as antigens detected antibody in any of the sera tested. Although the CF test appeared to be species-specific for cytomegaloviruses, and hence may have the most general utility for antibody detection, the greater sensitivity of the fluorescent antibody (FA) technique warrants its use for detecting small amounts of antibody when the correct antigen can be ascertained.
Immune Response of Mice to Nucleic Acids: Strain-Dependent Differences in Magnitude and Class of Antibody Production
Authors: Stollar B. David , Fuchs Sara , Mozes Edna 
Published: December 2022

Abstract
Several inbred mouse strains were immunized with denatured DNA-methylated bovine serum albumin (MBSA) complexes. The response of SJL/J mice was stronger over a period of 53 days (including 3 injections) than that of DBA/2, AKR/Cu, C3H/HeJ, C57BL/6 and BALB/c mice.
In a kinetic study of serum antibody levels, the early (10-day) responses of SJL/J and DBA/2 mice were similar, but the strength of SJL/J sera continued to rise while that of DBA/2 animals fell. After a boost at day 21, the SJL/J mice produced much higher antibody titers than did DBA/2 animals. In parallel assays for direct plaque-forming cells, DBA/2 animals yielded higher number of plaques at day 10, but similar values for both strains were derived at later times, including after the booster injection. Analysis by Sephadex G-200 gel filtration showed that the lower-responding DBA/2 animals produced only 19S antibody, while SJL/J mice produced both 19S and large amounts of 7S antibody.
A reversed pattern was observed after immunization with poly(A)·poly(U) or poly(I)·poly(C). In this case, DBA/2 mice responded more strongly than did SJL/J mice in production of antibodies to the double-helical polyribonucleotides.
Development of Primary γM, γG, and γA Anti-TNP Plaque-Forming Cell Responses in Vitro
Authors: Bluestein Harry G. , Pierce Carl W. 
Published: December 2022

Abstract
Trinitrophenylated bacteriophage φX174 (TNP-φX) is a potent in vitro immunogen capable of stimulating specific anti-TNP plaque-forming cell (PFC) responses in cultures of mouse spleen cells. Under optimal conditions, 10 × 106 spleen cells and 3 × 109 TNP-φX particles in 1 ml of culture medium, TNP-specific PFC responses representing the major mouse immunoglobulin classes, γM, γ1, γ2, and γA were detected. A study of kinetics of appearance of these immunoglobulin class-specific PFC revealed that an increase in γM PFC was detected within 24 hr of initiation of the cultures; the maximum γM PFC responses were on days 4 and 5. γ1 and γ2 PFC were not detectable until day 3 of culture and reached maxima on days 5 and 6. The anti-TNP PFC response to TNP-φX was almost completely suppressed by the addition of 100 µg TNP guinea pig albumin; the addition of free φX at a 10-fold excess over the TNP-φX immunogen suppressed the anti-TNP response about 70%.
Studies on Rabbit Lymphocytes in Vitro
Authors: Sell Stewart , Lowe Jennifer A. , Gell P. G. H. 
Published: December 2022

Abstract
Rabbit peripheral blood lymphocytes that have been stimulated in vitro to transform into blast cells by antiimmunoglobulin allotypic sera and then blocked by addition of serum containing the allotype with which the stimulating antiserum reacts may be restimulated by subsequent removal of the blocking serum and readdition of the stimulating antiserum. The extent of stimulation produced by stimulation-block-restimulation is the same as that produced by the continuous presence of the antiallotypic serum (continuous stimulation). However, if unstimulated cultures are incubated in vitro in neutral serum before stimulation with antiallotypic serum (delayed stimulation), the extent of stimulation is less than that produced by continuous stimulation or by stimulation-block-restimulation. Prestimulation of double homozygous lymphocytes with antiserum to one allotypic specificity activates the cells to respond to delayed restimulation with antiserum to the other allotypic specificity (mixed allotypic sequential stimulation, MASS). This MASS activation is not observed in cultures of mixtures of lymphocytes with antiallotypic sera to specificities contributed by different donors. These results indicate that continued contact of the transforming cells with the stimulating agent (signal maintenance) is required to consummate the transformation process and that cultures that are stimulated and blocked may be restimulated by a second specific signal.
Complement: Optimal Reaction Conditions for Guinea Pig C4
Authors: Linscott William D. 
Published: December 2022

Abstract
The efficiency of reactions involving C4 was markedly affected by antibody class, antibody concentration, temperature, ionic strength, SAC1 multiplicity, and SA:SAC1 ratio; C1-binding affinity was an important factor. Invariably, IgG-sensitized cells showed more lysis with a given amount of C4 than cells treated with IgM when other conditions were equal. Optimal reaction times and temperatures for C4 were as follows: a) for IgG-sensitized cells, 1 hr at 0°C if there are 1000 SAC1/cell, 2 hr or more at 0°C for 100 or fewer SAC1/cell; b) for high concentrations of IgM, the same conditions apply as for IgG; for lower concentrations (100 IgM/cell or less, same amount of C1), optimal conditions will vary depending on other factors (1). The above are for limiting amounts of C4. For higher concentrations of C4, times can be shortened somewhat, but the temperatures should not be altered. A further important consideration is that with IgM Ab, a 30 to 40 min preincubation of the EAC1 at 0°C before adding the C4 at 0°C markedly improves EAC14 reactivity in most cases (1). The optimal ionic strength for the above reactions is about 0.035 to 0.04.
With IgM antibody, very firmly bound C1 seemed to have a reduced effectiveness in the C4 reaction, as shown by lower lysis for heavily sensitized cells, and by reduced lysis at high vs low SA:SAC1 ratios, at 30°C. This was never the case with IgG.
C4 markedly increased the affinity with which C1 was bound to IgM-sensitized cells; half or more of the C1 could be bound so firmly that it failed to transfer at µ = 0.15. This effect was not seen with IgG antibody at the concentrations used, probably because smaller amounts of C4 were involved.
C1-binding affinity did not appear to affect the absolute or relative hemolytic efficiencies of rat or guinea pig EDTA-C with either class of antibody.
Lymphocyte Receptor Movement Induced by Sheep Erythrocyte Binding
Authors: Ashman Robert F. 
Published: December 2022

Abstract
When lymphocytes are exposed to reagents such as anti-immunoglobulin which cross-link cell surface determinants, those determinants may be drawn toward one pole of the cell into a “cap” (see References 2, 3).
Sheep erythrocytes bound to mouse spleen rosette-forming cells induce receptor redistribution similar to that produced by anti-immunoglobulin in two respects: 1) the kinetics and proportion of cells participating are highly temperature-dependent, and 2) the movements require active metabolism, but not protein synthesis. Erythrocyte-induced capping is slower than anti-immunoglobulin-induced capping and involves a smaller proportion of binding cells. By immunofluorescence the surface immunoglobulin is usually seen to move with the erythrocytes, but in about half the cases, the clearing of immunoglobulin is incomplete. Anti-immunoglobulin accelerates erythrocyte-induced capping, but fails to involve a larger proportion of cells unless a second order of cross-linking is introduced.
Immunoglobulin Response in Experimental Infection with Cell-Free and Cell-Associated Marek's Disease Virus
Authors: Jakowski R. M. , Fredrickson T. N. , Luginbuhl R. E. 
Published: December 2022

Abstract
The immunosuppressive effect of Marek's disease herpesvirus (MDV) on humoral antibody development was evaluated before the time of overt neoplasia. One-day-old line 7 chickens were tested for passively acquired MD agar gel precipitating (AGP) antibody and infected intra-abdominally with cell-free or cell-associated MDV. Infected chickens were subsequently inoculated with a sheep erythrocyte (SRBC) suspension and the humoral response to this antigen was evaluated by following SRBC hemagglutination titer.
Immunosuppression of IgG anti-SRBC antibody was found in chickens infected with cell-associated MDV virus regardless of whether maternal MD-AGP antibody was present. No significant suppression was found in similar chickens infected with cell-free MDV. IgM anti-SRBC antibody was unaltered in all of the infected groups receiving cell-free or cell-associated MDV. At termination of the experimental period (40 days postinoculation MDV), MD-AGP antibody was found in all infected groups. The incidence of this antibody was lowest in birds negative for maternal MD-AGP antibody and infected with cell-associated MDV, reflecting the severe suppression of anti-SRBC antibody encountered in this same group during the experimental period.
On the basis of these findings, humoral immunosuppression in MD appears to be a phenomenon associated with high doses of cell-associated virus. The effect primarily involves IgG antibody while IgM antibody appears to remain unaltered.
Isolation of Intermediates and Sequential Analysis of the Properdin System: The Role of Factor B
Authors: Brade Volker , Lee Gerald , Nicholson Anne , Mayer Manfred M. 
Published: December 2022

Abstract
On incubation with guinea pig serum zymosan (Z) combines with several factors (X) to form an intermediate complex (ZX), which is capable of inactivating purified C components C3 or C5 by cleavage. ZX formation increases with time of incubation and then declines due to a decay process. The Tmax times at 17°C, 27°C, and 37°C are 4 min, 2 min, and 1 min, respectively, for C3 cleavage by ZX. For C5 cleavage Tmax at 27°C and 37°C is 5 min and 2 min, respectively. ZX generation with C4-deficient guinea pig serum is slower than in normal guinea pig serum, which suggests that the classical pathway may accelerate the generation of ZX.
On reaction of Z with guinea pig serum, factor B activity is consumed. This is due, at least in part, to uptake of factor B by Z, as demonstrated by the fact that antibody to factor B inhibits C3 and C5 cleavage by ZX.
The Role of Properdin in the Alternate Pathway of C Activation
Authors: Götze Otto , Müller-Eberhard Hans J. 
Published: December 2022

Abstract
Properdin (P) was isolated from the euglobulins of human serum. Isolation was accomplished without the use of zymosan by a series of column chromatographic steps, including passage over CM-Sephadex C-50, DEAE-cellulose, Sepharose 6B and CM-cellulose. The final product was homogeneous by Ouchterlony analysis, immunoelectrophoresis, and polyacrylamide gel electrophoresis. Upon immunoelectrophoresis in 1% agarose at pH 8.6, P migrated toward the cathode similar to the behavior of P in aged serum (McLean and Michael, Proc. Soc. Exp. Biol. Med., 1972). The isoelectric point of P was above 9.5, the S-rate, determined by sucrose density gradient ultracentrifugation, was 5.5S. These properties are comparable to those reported by Pensky et al. (J. Immunol., 1968). There was no detectable change in the electrophoretic mobility of isolated C3PA or isolated C3 when either of these components was incubated with P.
Formation, Characterization and Function of a Stable Fluid Phase C5-C9 Complex
Authors: Kolb William P. , Müller-Eberhard Hans J. 
Published: December 2022

Abstract
Previous studies in this laboratory have allowed the formulation of a model for the molecular arrangement of C5, C6, C7, C8, and C9 on the surface of cells undergoing immune cytolysis with an assigned cumulative m.w. of 995,000. To verify directly the existence of a C5–C9 complex, serum samples containing radiolabeled terminal components were activated at 37°C with EA, antigen-antibody complexes, CVF, inulin or zymosan. Subsequent sucrose density gradient ultracentrifugation showed that all treatments cited led to the formation, in varying degrees, of rapidly sedimenting material which incorporated C5, C6, C7, C8, and C9, but not C3. The reaction was inhibited by 0.01 M EDTA and 0°C. The complex had a sedimentation coefficient of 22.4S, a diffusion coefficient of 1.98 × 10-7 cm2 sec-1 and thus a calculated m.w. of 1.04 × 106.
Further Studies on the Effect of Zinc Ions on Guinea Pig C
Authors: Amiraian Kenneth 
Published: December 2022

Abstract
The C titer of guinea pig serum, when treated twice with 0.3 volume of Chelex-100 (Dowex A-1), was reduced from 146 CH50/ml to 12 CH50/ml. Upon addition of 0.00015 M Ca++ and 0.0005 M Mg++, the treated serum had 121 CH50/ml. When adjusted to 6 × 10-6 M Zn++, in the presence of optimum Ca++ and Mg++, the titer was 143 CH50/ml. The optimum zinc ion concentration is dependent upon the concentration of sensitized cells (5 × 10-6 M Zn++ for 5 × 108 cells/7.5 ml). The effect of Zn++ is unrelated to the enhancement of guinea pig C by the zinc metalloenzyme carboxypeptidase A. Cadmium and nickel ions are also effective in the presence of optimum CA++ and Mg++. Cobalt has only a slight effect while manganese has no effect on guinea pig C. Kinetic studies indicate that zinc ions exert an inhibitory effect early in the immune hemolytic reaction and that enhancement is seen only after 16 min at 36°C.
Mechanism of Activation of C1 by Trypsin
Authors: Loos M. , Borsos T. 
Published: December 2022

Abstract
Trypsin activates C1 in serum as well as C1 bound to EAC4. At 37°C about 500 µg trypsin/ml are necessary for optimal activation of C1 in whole serum; 1 µg trypsin/ml is necessary to activate C1 in diluted serum (1:3000) and C1 bound to EAC4. The activation of precursor C1 (EAC14) to C1̄ (EAC1̄4) with or without trypsin is a time and temperature dependent reaction. The activation energy of the reaction EAC14 to EAC1̄4 is 7.5 kcal/mole and in the presence of trypsin 7.6 kcal/mole; the temperature coefficients (Q10) of both reactions are 1.57 and 1.55, respectively. Although there was no difference in the activation energies of both reactions, the reaction velocities were different. At a given temperature the value of the reaction velocity of the EAC1̄4 generation in the presence of trypsin was twice as high as in the reaction without trypsin.
Molecular Restriction of Anti-DNP Antibodies Induced by Dinitrophenylated Type III Pneumococcus
Authors: Montgomery Paul C. , Pincus Jack H. 
Published: December 2022

Abstract
Rabbits were hyperimmunized with ε-DNP-lysine covalently coupled to type III encapsulated pneumococci (DNP-Pn vaccine). After a preimmunization with pneumococcal vaccine followed by immunization with DNP-Pn vaccine, 11 of 13 rabbits produced anti-DNP antibodies with titers ranging from 0.28 to 1.30 mg/ml. The affinities of the anti-DNP antibodies were low (105 liters/mole). The molecular heterogeneity of 7 of the 11 responding rabbits, as determined by isoelectric focusing, was markedly reduced. Upon continued immunization some rabbits maintained or increased their restriction while others exhibited a loss of restriction and evidence of molecular heterogeneity. Although titers and heterogeneity generally increased during prolonged immunization, association constants for the anti-DNP antibodies remained in the range of 105 liters/mole. The present experiments indicate that a bacterial carrier can have a marked effect on the structural complexity of anti-DNP antibodies and provide a new means of obtaining structurally restricted anti-hapten antibodies.
Alternative Potentiating and Inhibitory Effects of GVH Reaction on Formation of Antibodies Against a Thymus-Independent Polysaccharide (SIII)
Authors: Byfield Patricia , Christie George H. , Howard James G. 
Published: December 2022

Abstract
The direct PFC response to SIII (type 3 pneumococcal polysaccharide) has been studied in adult (C57BL × CBA-T6T6) F1 mice in which graft-vs-host (GVH) reaction was induced by parental strain lymphoid cells. The response was potentiated for 3 to 6 days after injection of lymphoid cells when SIII was injected either separately or coupled to the cells. An analysis of this effect revealed: a) that it requires recognition of the host by viable donor thymus-derived (T) lymphocytes and their subsequent proliferation (the reverse, host-vs-graft, situation was ineffective); and b) that it seems to be attributable to a different T cell function than that responsible for specific “helper” activity.
On the other hand, F1 mice examined 6 to 109 days after injection of 8 × 107 parental spleen cells were totally unresponsive to SIII. Furthermore, there was no response to SIII in lethally irradiated mice repopulated with spleen cells from GVH animals or with a mixture of GVH and normal spleen cells. Treatment of the GVH cells with anti-ϑ serum partially alleviated this suppressive effect.
We conclude that potentiation and suppression are both attributable to T cell activity, and that they seem to differ qualitatively rather than quantitatively. Macrophages may be involved in an intermediary effector capacity in the suppressive phenomenon.
Genetics of the Immune Response
Authors: Pauli Raimund Di 
Published: December 2022

Abstract
Cross-reactivity of IgM antibodies, against a lipopolysaccharide, has been used as a marker for the variable part of these antibodies. BALB/c and DBA/2An differ in the antibody specificity produced against the same lipopolysaccharide. Backcross data are compatible with a control by a single gene. About half of the F1 animals resembled the BALB/c parent and the other half the DBA/2An parent. This suggests that only one allele is expressed in heterozygous animals.