bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhibition of murine plaque-forming cell responses in vivo by ribavirin.
Authors: Peavy D L , Powers C N , Knight V 
Published: December 2022

Abstract
The effects of ribavirin, a potent inhibitor of RNA and DNA virus replication, on the generation of primary plaque-forming cell (PFC) responses in vivo has been investigated. Intraperitoneal administration of ribavirin 1 day after immunization of C3H/HeJ mice with sheep erythrocytes (SRBC) suppressed splenic IgM and IgG PFC responses by 60 to 90%. Primary IgM PFC responses of C3HeB/FeJ mice to bacterial lipopolysaccharides (LPS), a T-independent antigen, were also inhibited to a similar extent. Inhibition of splenic PFC responses, without significant reduction in nucleated cell recoveries, was dose dependent between 0.5 and 4 mg ribavirin. Varying the time of treatment determined that optimal inhibitory activity occurred when ribavirin was administered simultaneously or 1 day after antigen. Kinetic analysis of PFC responses in ribavirin-treated mice revealed that suppression did not result from a delay in development since reduced numbers of PFC were found at all times after immunization. Ribavirin-treatment after primary sensitization in vivo also impaired the capacity of spleen cells to develop secondary PFC responses in vitro, indicating that ribavirin also inhibited memory cell generation.
Flow cytofluorometric analysis of the binding of Vicia villosa lectin to T lymphoblasts: lack of correlation with cytolytic function.
Authors: MacDonald H R , Mach J P , Schreyer M , Zaech P , Cerottini J C 
Published: December 2022

Abstract
The relationship between the binding of Vicia villosa (VV) lectin and the expression of cytolytic function in T lymphoblasts has been investigated using flow cytofluorometric techniques. Spleen cells activated in vitro in 5-day mixed leukocyte cultures (MLC) were incubated sequentially with VV, rabbit anti-V antiserum, and fluoresceinated sheep anti-rabbit IgG. When these stained MLC cells were passed on a flow cytometer gated to exclude nonviable cells and small lymphocytes, a single heterogeneous peak of fluorescence was seen, as compared to control MLC cells that had not been incubated with VV. Fluorescence of lymphoblasts was dependent upon lectin dose and was eliminated when staining was performed in the presence of N-acetyl-D-galactosamine, the appropriate competitive sugar for VV. T cell blast populations activated against H-2, Mls, or parasite antigens all had comparable levels of fluorescence after staining with VV, although the cytolytic activity of these cells varied widely. Furthermore, when MLC lymphoblasts binding large or small amounts of VV were sorted on the basis of their relative fluorescence intensity and tested for cytolytic function, no appreciable difference in activity between the 2 populations was observed. These results are inconsistent with the hypothesis that VV binds selectively to cytolytic T lymphocytes.
Age-associated changes in Epstein-Barr virus-induced human lymphocyte autoantibody responses.
Authors: Fong S , Tsoukas C D , Frincke L A , Lawrance S K , Holbrook T L , Vaughan J H , Carson D A 
Published: December 2022

Abstract
In the present investigation we have studied the capacity of the Epstein-Barr virus (EBV), a ubiquitous human B lymphocyte polyclonal activator, to induce cultured peripheral blood lymphocytes from umbilical cords, young adults (20 to 40 yr old), and elderly adults (75 to 90 yr old) to form IgM antibodies to human IgG or human thyroglobulin. The EBV preparation used was shown to exert its B cell stimulatory effect independently of T cell-suppressor effects. The cultures were studied in limiting dilution analyses, and the data were taken to represent relative numbers of B cell precursors of autoantibody-forming cells in the 3 age groups. The results showed: 1) the EBV-inducible IgM anti-IgG and anti-thyroglobulin-producing cells increased in number from birth to old age; 2) the rise occurred at different times of life for the 2 autoantibodies, anti-IgG reactive B cells increasing between birth and young adulthood, and anti-thyroglobulin reactive B cells between young adulthood and old age; 3) the apparent relative avidity of the anti-IgG for antigen was higher in the elderly adults than in the younger adults. We believe these findings are determined by differences in the frequencies of the respective self-reactive B cells in the circulation. What physiologic or environmental factors determine the differential expansions of the human autoreactive B lymphocytes for IgG and thyroglobulin are not known. It seems possible that individual variations in the sizes of these pools may be a factor in determining susceptibility to autoimmune disease.
Bacterial lipopolysaccharide (endotoxin) interferes with the induction of tolerance and primes thymus-derived lymphocytes.
Authors: Parks D E , Walker S M , Weigle W O 
Published: December 2022

Abstract
The injection of deaggregated human gamma-globulin (DHGG) into mice results in the establishment of specific immunologic unresponsiveness in T and B lymphocytes. However, the additional injection of bacterial lipopolysaccharide (LPS) 3 hr later converts the tolerogenic DHGG into an immunogen for both helper T and B cells. This generation of immunocompetence to HGG during interference with tolerance induction by LPS is demonstrated by both a primary plaque-forming cell response to DHGG + LPS and a secondary antibody response to a subsequent antigenic challenge. The secondary response to antigen stimulation in the B cells is, however, T cell dependent. Interference with tolerance induction in antigen-specific helper T cells can be demonstrated by challenge with the DNP-HGG hapten-carrier conjugate or by adoptive cell transfer with primed B cells and subsequent challenge with immunogenic HGG. Furthermore, helper T cells in the spleen and thymus become primed by DHGG + LPS as evidenced by their cooperation with primed B cells in the adoptive transfer assay. In addition to its interference with tolerance induction, LPS injected with either tolerogenic or immunogenic HGG also facilitates priming of helper T cells for the response to DNP-HGG. These data indicate that exposure of antigen-specific helper T and B cells to antigen alone results in the induction of tolerance, whereas induction of immunocompetence in these cells requires at least 2 signals, 1 provided by interaction with antigen and a 2nd delivered by a nonspecific stimulus similar to that provided by LPS in the present experiments.
Antigens of Ambrosia elatior (short ragweed) pollen. I. Crossed immunoelectrophoretic analyses.
Authors: Løwenstein H , Marsh D G 
Published: December 2022

Abstract
A crude extract of short ragweed pollen was obtained by extraction, centrifugation, dialysis and freeze-drying. Crossed immunoelectrophoresis, with a high-titer purified rabbit antibody fraction, revealed that the extract contained at least 52 antigens, of which 33 migrated toward the anode, 16 toward the cathode, and 3 toward both the anode and cathode. The electrophoretic precipitation pattern indicated a great deal of electrophoretic heterogeneity in several of the antigens. The overall distribution of apparent m.w. for 35 of the 52 antigens and the approximate m.w. for 19 identified antigens were determined by a combination of gel filtration and immunochemical analysis. Among antigens with m.w. weights less than or equal to 10,000, 8 of 10 were basic; on the other hand, all 5 identified antigens with m.w. above 40,000 were acidic. The apparent pI distribution for 30 antigens, and more precise pI values for 20 of 52 antigens, were determined by means of sucrose-gradient isoelectric focusing. The data obtained provide a reproducible reference system of considerable use in ragweed allergen chemistry and enable one to predict conditions for isolation of ragweed antigens.
Genetic influences on the augmentation of natural killer (NK) cells during murine cytomegalovirus infection: correlation with patterns of resistance.
Authors: Bancroft G J , Shellam G R , Chalmer J E 
Published: December 2022

Abstract
Cytotoxic activity attributable to natural killer (NK) cells was augmented in the spleens of mice infected with murine cytomegalovirus (MCMV). Stimulation was observed as early as 10 hr after virus administration but was dependent upon the dose used, and in particular, the host genotype. Effector cells were capable of killing a range of tumor cell targets as well as normal syngeneic thymocytes, and were induced in nude (nu/nu) and heterozygous (nu/+) mice. A significant correlation existed between resistance to the lethal effects of MCMV infection and the degree of NK cell augmentation by this virus in 10 of 11 strains examined. Non-H-2 related differences in activity were observed, but a clear association between high NK cell responses and the possession of a particular H-2 haplotype was not apparent. Beige mutant C57BL/6J mice, previously reported as defective in NK cell function were susceptible to MCMV and expressed low levels of cytotoxicity during infection. Thus, the genetically controlled stimulation of NK cells in the early stages of infection with MCMV may contribute to the genotype related patterns of resistance seen with this virus.
Induction of IgG production in a human monoclonal B lymphoblastoid cell line by a B cell-specific monoclonal antibody.
Authors: Miki Y , Kishi H , Muraguchi A , Maruyama S , Kishimoto S , Yamamura Y , Wang C Y , Kishimoto T 
Published: December 2022

Abstract
IgG production was induced in a human B blastoid cell line, CESS, by stimulation with a human B cell-specific monoclonal antibody (IIIA4). The number of IgG-producing cells reached its maximal level within 48 hr after incubation with IIIA4. IgG-producing cells induced by an optimal concentration of the antibody was about one-half as many as those induced with TRF, but higher concentrations of the antibody were rather inhibitory. Simultaneous addition of an optimal concentration of the antibody with TRF partially inhibited TRF-induced IgG production in CESS cells, but higher concentrations of the antibody did not block TRF-induced IgG production. TRF activity was completely absorbed with IIIA4-coated CESS cells as well as nontreated CESS cells. These results suggested that the membrane antigen recognized by IIIA4 was not the acceptor molecule for TRF. IIIA4 did not show any inhibitory effect on PWM-induced proliferation of normal B cells, but completely inhibited PWM-induced Ig production of normal B cells.
Regeneration of T cell subpopulations after bone marrow transplantation: cytomegalovirus infection and lymphoid subset imbalance.
Authors: Schroff R W , Gale R P , Fahey J L 
Published: December 2022

Abstract
Immune reconstitution was studied serially by using T lymphocyte cell surface differentiation antigens in 37 individuals receiving bone marrow transplants. Antigen expression was assessed by immunofluorescence analysis using monoclonal antibodies to T lymphocytes including Leu-3, which defines a T lymphocyte subpopulation in healthy individuals with T helper or inducer activity (L3+), and Leu-2, which defines a T lymphocyte subpopulation in healthy individuals with T helper or inducer activity (L3+), and Leu-2, which defines a T lymphocyte subpopulation with suppressor or cytotoxic activity (L2+). These studies demonstrated that the L2+ subpopulation regenerated more rapidly after transplant than did the L3+ subpopulation. Imbalances between these two T lymphocyte subpopulations, indicated by a decreased L3/L2 ratio, persisted for periods up to 12 mo post-transplant. Expression of a cell surface antigen associated with immature lymphocytes (OKT-10), and of HLA-DR (Ia-like) antigens was markedly increased during the post-transplant period. HLA-DR antigen expression did not appear related to immune activation in that increased reactivity was not detected with a monoclonal antibody (anti-TAC) specific for activated T cells. These observations in bone marrow transplant recipients and other disorders characterized by lymphoid restoration or immaturity indicate that inversion of the normal L3/L2 ratio and increased expression of OKT-10 and HLA-DR antigens may be features of a regenerating immune system. Furthermore, serial observation of individual patients indicated that infection with cytomegalovirus was associated with a progressive decrease in the L3/L2 ratio.
Abnormal natural killer cell activity in systemic lupus erythematosus: an intrinsic defect in the lytic event.
Authors: Katz P , Zaytoun A M , Lee J H , Panush R S , Longley S 
Published: December 2022

Abstract
The natural killer (NK) cell activity in fifteen systemic lupus erythematosus (SLE) patients was investigated by employing 51-chromium- (51Cr) release microcytotoxicity and single cell cytotoxicity assays against K562 target cells. Although the SLE patients as a group had depressed NK function in the 51Cr-release assay compared to normal subjects (p less than 0.005), those with clinically active disease displayed the greatest impairment in this activity (p less than 0.001). Active SLE patients were deficient in overall NK activity (Vmax) (p less than 0.005) but had normal percentages of potentially cytotoxic target binding cells (TBC). These TBC, however, were unable to normally kill bound target cells (p less than 0.01), which is indicative of a deficiency of "active" NK cells (p less than 0.005). Those NK cells with intact cytotoxic capabilities could "recycle" and repeat the lytic sequence normally. Exposure of normal lymphocytes to SLE sera did not impair any phase of NK function. These studies indicate that defective NK activity in SLE is secondary to an abnormality in the lytic event itself and is not due to a deficiency of NK cells, an abnormality in target binding, or an inability of NK cells to lyse multiple targets. Additionally, serum factors do not appear to play a major etiologic role in the cytotoxic abnormalities of these patients.
Cyclosporin receptors on human lymphocytes.
Authors: Ryffel B , Götz U , Heuberger B 
Published: December 2022

Abstract
Utilizing (3H) cyclosporin C (3H CS-C), a dihydroderivative of cyclosporin A (CS-A), an assay for cyclosporin receptors on human peripheral blood lymphocytes was developed. The specific binding of (3H) CS-C was saturable, time-dependent, and reversible. A Kd of 1.2 x 10(-7) M and a maximum binding capacity (Bmax) of 7 pmol/10(6) cells was calculated from equilibrium binding studies. A Scatchard analysis confirmed a single population of high affinity binding sites and about 7 x 10(5) sites/cell. Kinetic analysis of specific binding at 37 degrees C yielded a pseudo-first order rate association constant of 1.1 x 10(6) M-1 min-1 and a zero order dissociation rate constant of 0.19 min-1. The Kd 1.7 x 10(-7) M calculated from kinetic studies agreed well with the value of 1.2 x 10(-7) M determined in equilibrium binding studies. Regarding the specificity of binding, (3H) CS-C binding to lymphocytes was inhibited with CS-A and CS-C; however, no inhibition with the biologically inert keto-CS-A was observed. Mitogens and various growth factors did not compete for the binding site when added simultaneously with the radiolabel. However, pretreatment with T cell mitogens such as PHA, Con A, or the OKT3 antibody reduced (3H) CS-C binding significantly. These results suggest that the binding site for CS-A is closely associated with the mitogenic receptor on lymphocytes.
Cord IgM antibody specific for human killer T cells: T lymphocytotoxic human fetal antibody (TLFA) recognizing maternal killer T cells proliferating in the presence of interleukin 2.
Authors: Miyagawa Y , Komiyama A , Akabane T , Uehara Y , Yano A 
Published: December 2022

Abstract
T lymphocytotoxic human fetal antibody- (TLFA) containing cord IgM (TLFA IgM) was purified from cord blood. The proliferation of maternal mixed lymphocyte culture-(MLC) induced and long-term cultured T cells (LCT) specific to the paternal non-T cells in the presence of interleukin 2 (IL 2) was inhibited by treatment with the respective TLFA IgM plus complement (C). Sixty-six to 78% of Leu-2a-positive maternal LCT were stained with the respective TLFA IgM, as determined by anti-Leu antibodies and TLFA IgM double-staining. Moreover, TLFA IgM plus C treatment reduced the killer activity of the respective maternal LCT against the PHA-induced paternal target cells. Therefore, TLFA-positive killer T cells of maternal LCT belong to certain killer T cell subsets of Leu-2a-positive pan-killer T cells, and TLFA contains a potential antibody against maternal killer T cells.
Dissection of immunoregulatory subpopulations of T lymphocytes within the helper and suppressor sublineages in man.
Authors: Gatenby P A , Kansas G S , Xian C Y , Evans R L , Engleman E G 
Published: December 2022

Abstract
The helper/inducer (Leu-3) and suppressor/cytotoxic (Leu-2) sublineages of human peripheral blood T cells can both the subdivided into functionally distinct subsets with anti-Leu-8, a new monoclonal antibody that identifies 75 +/- 10% of the Leu-3 cells and 60 +/- 10% of the Leu-2 cells. Using the autologous MLR as a T cell-dependent stimulus for immunoglobulin synthesis, we have shown that the major helper effect for antibody formation lies within the numerically minor Leu-3,8- subset. In addition, neither Leu-2,8- cells alone suppress Leu-3-induced immunoglobulin synthesis, but in combination these subsets are markedly inhibitory. These results indicate that at least two phenotypically distinct cell types of suppressor lineage interact to produce suppression of an immune response in man.
A monoclonal antibody specific for the Thomsen-Friedenreich cryptic T antigen.
Authors: Rahman A F , Longenecker B M 
Published: December 2022

Abstract
A monoclonal antibody (49H.24) is described that was made after immunization of BALB/c mice with human neuraminidase-treated erythrocytes (NE-RBC). 49H.24 is an IgM and reacts with NE-RBC but not untreated, normal human RBC. As little as 100 pg of antibody protein produced detectable direct agglutination of, or binding to, NE-RBC. The fine specificity of 49H.24 was determined by using a series of synthetic sugar haptens as inhibitors of agglutination or binding of 49H.24 to NE-RBC. Only synthetic T hapten (beta Gal(1 leads to 3)alpha GalNAc) produced complete inhibition of agglutination or binding, and no inhibition was produced by several other closely related haptens. Synthetic T hapten-coated silica beads (Synsorb) were used to affinity purify 49H.24. Affinity-purified antibody was radiolabeled with 125I and used in a sensitive competition assay to detect natural T antigen associated with cell membranes or in soluble form. The potential use of this or similar monoclonal antibodies as probes for an important human tumor marker is discussed.
A rapid simple method of basophil purification by density centrifugation on Percoll.
Authors: Raghuprasad P K 
Published: December 2022

Abstract
This study describes simple and relatively rapid methods of purifying basophils from human peripheral blood. Our initial studies defined the densities of basophils in several donors and helped develop strategies for selectively concentrating basophils by isopyknic centrifugation over Percoll. We layered anticoagulated blood over Percoll of appropriate density, centrifuged these for 10 min, and collected the cells held in Percoll separately from the overlying band of mononuclear cells. Most of the basophils were distributed between densities of 1.072 and 1.078 g/ml, with a peak at approximately 1.074 to 1.076 g/ml. Basophil purity of 24.4 +/- 4% (range 5.6 to 50%) was achieved in a Percoll gradient of 1.076 g/ml due to both the increased numbers of basophils and the low numbers of mononuclear cells at this gradient. The cells isolated by this method are viable, appear morphologically normal, and release histamine to various stimuli in a normal manner. A second centrifugation of the cells obtained from this density over appropriate discontinuous gradients of Percoll leads to further enhancement of basophil purity. The main limitation of this technique appears to be the relatively low yield (percent of recovery) of the basophil (less than or equal to 20% for the two-step procedures).
Experimental murine hypersensitivity pneumonitis: multigenic control and influence by genes within the I-B subregion of the H-2 complex.
Authors: Wilson B D , Sternick J L , Yoshizawa Y , Katzenstein A L , Moore V L 
Published: December 2022

Abstract
An animal model of hypersensitivity pneumonitis was developed in the mouse by immunization with pigeon dropping extract (PDE) in complete Freund's adjuvant, followed by daily aerosol challenge with soluble specific antigen. C3H/He (H-2k) mice developed intense diffuse interstitial lung disease and were classified as high responders. On the other hand C57BL/10 (H-2b) mice developed only mild perivascular infiltration. Moreover, although high-responder C3H/He mice developed delayed hypersensitivity to PDE, low-responder C57BL/10 mice failed to develop this reactivity. Breeding studies in F1 and F2 progeny of C3H/He high responders and C57BL/10 low responders showed that responsiveness was multigenic. B10.BR (H-2k) mice also developed intense PDE-induced diffuse interstitial lung disease, suggesting that genes within the H-2 complex influence the development of pulmonary inflammation. On the other hand, C3H.SW (H-2b) mice were also high responders, possibly because of non-H-2 genes in the C3H/He background that influenced responsiveness. Studies in H-2 recombinant strains with C57BL/10 backgrounds mapped the H-2-linked genes that influence responsiveness within the I-B subregion.
Schistosoma mansoni surface antigen defined by a rat monoclonal IgG2a.
Authors: Dissous C , Grzych J M , Capron A 
Published: December 2022

Abstract
A schistosomula surface antigen of 38,000 daltons has been isolated by using a rat monoclonal IgG2a that has been shown to confer protection against S. mansoni infection by passive transfer in rats. This antigen is one of the previously characterized surface proteins reacting with sera from various infected hosts, including rat, mouse, monkey, and human. Studies on parasites of different developmental stages indicated the presence of this antigen on cercariae and skin-derived or mechanically transformed schistosomula.
Tumor-specific antigen of murine T-lymphoma defined with monoclonal antibody.
Authors: Allison J P , McIntyre B W , Bloch D 
Published: December 2022

Abstract
A panel of hybridomas was constructed by fusion of P3X63Ag8 myeloma cells with spleen cells from a BALB/c mouse that had been immunized with a C57BL/Ka x-ray-induced lymphoma, C6XL. One of forty-three hybridomas secreting antibodies reactive with the tumor cells was found to be unreactive with normal spleen cells in a radioimmunometric assay. This antibody, designated 124-40, was unreactive with normal adult thymus, spleen, lymph node, or bone marrow cells, or with fetal spleen or thymus cells in radioimmunometric or radioimmunoprecipitation assays. Flow microfluorometric analysis of these nonmalignant lymphoid cells failed to reveal subpopulations reactive with MAb 124-40. The antibody was highly specific for the lymphoma cells used for immunization and did not react with a panel of other spontaneous or x-ray-induced or chemically induced lymphomas. The antigen reactive with MAb 124-40 was isolated by radioimmunoprecipitation and found to be a glycoprotein composed of disulfide-bonded subunits of 39,000 m.w. and 41,000 m.w. A cell surface component of similar structure, but not reactive with MAb 124-40 could be detected by two-dimensional electrophoresis in extracts of purified T cells, but not B cells. These results suggest that the apparently individually specific lymphoma antigen reactive with MAb 124-40 might be a clonally expressed epitope carried by a T cell surface component.