bluuebunny/crossref_metadata_2025_split huggingface dataset:
The variable region of human immunoglobulins. I. Serologic and structural correlations of antigenic markers common to V lambda I and V lambda IV proteins (isotypic cross-reactivities).
Authors: Rivat-Peran L , Tischendorf F W , Dumitresco S M , Rivat C , Tischendorf M M , Haas H , Deutsch H F 
Published: December 2022

Abstract
Sixty-eight human lambda-chain sources including representatives of the five different subgroups were studied for the distribution of the serologic markers ST, 111, and VOR The variable region character of these antigenic determinants has been demonstrated for those proteins whose primary structures had been partially or completely determined previously. The lambda-chain sub-groups I and IV are readily distinguished antigenically but the specificity designated VOR is shared between them and is absent in the II, III, and V subtypes. The results of these studies are discussed with respect to the possible relationships of the structural genes controlling the synthesis of the lambda-chain subgroups, and some potential phylogenetic and functional meaning of the heterogeneities is revealed.
Suppression splenic T lymphocytes in human hepatosplenic Schistosomiasis mansoni.
Authors: Ellner J J , Olds G R , Kamel R , Osman G S , el-Kholy A , Mahmoud A A 
Published: December 2022

Abstract
Splenic suppressor cell activity was evaluated in 10 patients with advanced hepatosplenic Schistosomiasis mansoni undergoing elective splenectomy. We used cell mixing experiments to assess the effect of mitomycin-C-treated spleen cells on antigen and mitogen-induced 3H-thymidine incorporation of responder cells. The suppressor to responder ratio was 1.0. Spleen cells from 7 of 10 patients caused at least 20% suppression of phytohemagglutinin-induced 3H-thymidine incorporation of one or more populations of responder cells (spleen cells, autologous and allogeneic peripheral blood mononuclear cells)Responses of peripheral blood mononuclear cells to streptokinase-streptodornase and schistosome soluble egg and worm antigen preparations also were inhibited by co-cultured spleen cells. An inverse correlation was apparent between the spleen cell response to PHA and the suppressor activity of that spleen cell population (r = -0.74, p less than 0.05). Cell purification procedures showed that the active suppressor splenic cell was non-adherent and rosetted neuraminidase-treated sheep erythrocytes. This splenic suppressor T lymphocyte may modulate splenic and peripheral blood lymphocyte responses in patients with hepatosplenic schistosomiasis.
Requirements for T cells in alloantigen-induced generation of non-T cell-mediated cytotoxicity against syngeneic mouse sarcoma cells.
Authors: Paciucci P A , Macphail S , Bach F H , Zarling J M 
Published: December 2022

Abstract
In vitro stimulation of BALB/c spleen cells with allogeneic normal cells results in the generation of effector cells cytotoxic for syngeneic SV40 virus-induced MKSA fibrosarcoma cells. The conclusion that natural killer (NK) cells are activated that lyse the syngeneic tumor cells derives from findings that 1) treatment of the allostimulated BALB/c effector cells with anti-theta serum and complement does not ablate cytotoxicity against syngeneic MKSA tumor cells and 2) allostimulation of congenitally athymic (nu/nu) BALB/c mice results in significant cytotoxicity against MKSA tumor cells but not against allogeneic target cells. The requirement for the presence of theta-positive cells in alloantigen-induced activation of NK cells cytotoxic for syngeneic tumors was studied. Spleen cells from conventional BALB/c mice are cytotoxic for syngeneic MKSA tumor cells after stimulation with anti-theta serum-treated allogeneic cells or with allogeneic nude cells. In contrast, stimulation of BALB/c nude spleen cells with anti-theta serum-treated allogeneic cells or allogeneic nude cells fails to give rise to anti-tumor effector cells. Thus, theta-positive cells (presumably T cells) are required for alloantigen induced non-T cell-mediated lysis of syngeneic tumors.
Staphylococcus aureus Cowan I-induced immunoglobulin production in human cord blood lymphocytes.
Authors: Ruuskanen O , Pittard W B , Miller K , Pierce G , Sorensen R U , Polmar S H 
Published: December 2022

Abstract
Human cord blood mononuclear cells (MNC) were stimulated with antibiotic killed Staphylococcus aureus Cowan I bacteria (S. aureus) or pokeweed mitogen (PWM) and cultured for 6 days. Immunoglobulin synthesis and secretion was measured with the indirect protein A plaque-forming cell (PFC) assay. All 14 cord blood specimens stimulated with S. aureus produced PFC comparable to that measured in adult peripheral blood cultures. PWM induced only minimal responses in cord MNC whereas good responses were demonstrated in adult cell cultures. The majority of the cord blood immunoglobulin synthesizing cells produced IgM, however, significant production of IgA was also seen. These observations were confirmed by detection of intracytoplasmic immunoglobulin in plasma cells with the use of fluorescent anti-immunoglobulin antibodies.
Allotypy of rabbit immunoglobulins: a fifth allele at the a locus.
Authors: Brézin C , Cazenave P A 
Published: December 2022

Abstract
Studies in wild rabbits (Oryctolagus cuniculus) allowed the detection of a fifth allele (a101) at the a locus of rabbit immunoglobulins. The structures responsible for the A101 allotypic specificity have been found on both IgG and IgM. Their location is on the Fab fragment, on the H chain. None of the rabbits possessing A101 allotypic specificity possessed two known allotypic specificities of the a series. Genetic evidence by breeding studies agree with assignment of A101 to the a series and allow to designate this allotypic specificity as a101. a101 has been found in wild rabbits in different areas in France. It has no detectable cross-reactivity with the known allotypes. The genetic polymorphism of immunoglobulins is much larger in the Oryctolagus cuniculus species than the one described in the domestic form of the species.
Characterization of a human macrophage-like cell line stimulated in vitro: a model of macrophage functions.
Authors: Larrick J W , Fischer D G , Anderson S J , Koren H S 
Published: December 2022

Abstract
When cells of human macrophage-like cell line U937 are cultured in the presence of medium conditioned by mixed lymphocyte culture (MLC), PHA- or Con A-stimulated lymphocytes they demonstrate morphologic and functional characteristics of stimulation. The cells become larger, their surface more villous, and the cytoplasm has increased numbers of lysosomes and phagosomes. There is a marked (at least 10-fold) increase in antibody-dependent cellular cytotoxicity (ADCC) against both erythroid and tumor targets accompanied by increased expression of Fc receptors (FcR). There is also an augmentation of antibody-dependent phagocytosis. Medium conditioned by unstimulated lymphocytes, a B lymphoblastoid cell line or a fibroblast cell line produce very little stimulation of U937 cells. U937 cells gradually lose their increased ADCC capacity if they are washed free of conditioned medium (CM) but can be maintained in a stimulated state for long periods of time by culturing them in medium supplemented with PHA-CM at a concentration of 2%. Stimulation of macrophage-like cell line U937 may provide a useful model for further study of mechanisms of macrophage cytotoxicity and its modulation by products of activated lymphocytes.
In vitro cooperation of a antigen-specific T cell-derived helper factor, B cells, and adherent cells or their secretory product in a primary IgM response to chicken MHC antigens.
Authors: Shiozawa C , Longenecker M B , Diener E 
Published: December 2022

Abstract
The primary in vitro IgM response to the major histocompatibility (MHC) antigens expressed on chicken red blood cells (CRBC) has been shown to critically depend on the cooperation between antigen-specific helper factor from CRBC-primed thymus-derived helper (T) cells, bone marrow-derived (B) cells, and radioresistant (A) cells. A 500- to 1000-fold enrichment for immunocompetent B cells by means of a rosette technique permitted the culturing of as few as 2000 B cells that yielded on the average 500 plaque-forming cells against CRBC within 3 days of culture. Cell reconstitution experiments clearly showed that the presence of A cells can be circumvented by an A cell-derived secretory product. This is in disagreement with the hypothesis that helper factor acts as a mediator for antigen presentation on the A cell surface membrane. The spectrum of helper factor cross-reactivity with respect to certain alleles of the B locus was found comparable to that of antibody.
Evidence for abnormalities in separate lymphocyte populations in NZB mice.
Authors: Taurog J D , Smathers P A , Steinberg A D 
Published: December 2022

Abstract
Neonatally thymectomized, lethally irradiated NZB X DBA/2 and DBA/2 X NZB F1 mice were reconstituted with NZB or DBA/2 bone marrow cells and NZB or DBA2 thymocytes. Of the four resulting groups of recipient F1 mice, those given NZB bone marrow cells developed high serum IgM levels, irrespective of the thymocyte donor strain. In contrast, recipients of NZB thymocytes were resistant to induction of tolerance to BCG, irrespective of the bone marrow donor strain. Only recipients of NZB bone marrow cells made spontaneous antierythrocyte autoantibodies; of these, the responses of NZB thymocyte recipients were greater and more consistent than those of DBA/2 thymocyte recipients. Recipients of either NZB bone marrow cells or NZB thymocytes made antibody responses to ssDNA; the highest anti-ssDNA responses occurred in recipients of both NZB bone marrow cells and NZB thymocytes. We conclude that functional abnormalities in separate lymphocyte populations underlie different immune abnormalities in NZB mice.
Murine lymphocyte alloantigens. II. The Ly-7 locus.
Authors: Potter T A , Morgan G M , McKenzie I F 
Published: December 2022

Abstract
The murine Ly-7 locus was identified by the reactivity of alloantisera prepared as B6,C-H-2d x CXBG)F1 anti-CXBK. Most strains, except C57BL/6 and related strains, were Ly-7.2+. Absorption analysis demonstrated that the Ly-7 specificity was only found on lymphocytes and was absent from liver, kidney, brain, and red blood cells. Direct testing by cytotoxicity and protein A rosetting showed that Ly-7 is expressed in very low amounts on thymocytes, but is readily detectable on more mature T and B lymphocytes (including antibody-forming cells), with the greatest expression on B cells. Typing backcross mice with Ly-7.2 Ly-4.2, H-2.33 antisera showed that Ly-7 is not linked to the Ly-4 or H-2 loci. In raising the antisera by hyperimmunization, it was found that the antibody response to the Ly-7.2 specificity was influenced by an H-2-linked immune response gene.
A monoclonal antibody defining a lymphoma-associated antigen in man.
Authors: Nadler L M , Stashenko P , Hardy R , Schlossman S F 
Published: December 2022

Abstract
A monoclonal antibody (Ab 89) was developed against a lymphoma-associated antigen on the tumor cells of a patient (N.B.) with a B cell, poorly differentiated lymphocytic lymphoma (D-PDL). By indirect immunofluorescence, Ab 89 was shown to react only with N.B. lymphoma cells and was unreactive with normal N.B. lymphoid cells, normal fractionated peripheral blood cells, other normal lymphoid tissues, fetal tissues, and non-lymphoid malignant cells. In addition, Ab 89 was unreactive with conventional immunoglobulins, private and public HLA antigens, or Ia-like antigens. More importantly, Ab 89 was reactive with some B cell lymphoid malignancies. Of the 57 B cell lymphomas tested, it was found that Ab 89 reacted with approximately 10% of B cell D-PDL and B cell chronic lymphocytic leukemia (CLL). Of interest was the finding that N.B. serum contained a circulating antigen which could specifically block the reactivity of Ab 89. The data obtained suggests that Ab 89 defines a tumor-associated antigen shared by a unique subgroup of B cell lymphomas. The group of patients reactive with Ab 89 did not fall into any histopathologic classification system. These data support the notion that there is greater heterogeneity of B cell lymphomas than may have been previously recognized.
IgG1 and IgG2b share the Fc receptor on mouse macrophages.
Authors: Diamond B , Scharff M D 
Published: December 2022

Abstract
Monoclonal IgG1 anti-SRBC has been used to study the binding of monomeric and aggregated IgG1 to Fc receptors on mouse macrophages. Aggregated IgG1 was found to bind to Fc receptors on two macrophage cell lines and on primary macrophages. It competes for binding with IgG2b and not IgG2a. Like the binding of IgG2b, the binding of IgG1 is unaltered at 4 degrees C and is insensitive to trypsin or cytochalasin B. Antigen-bound IgG1, like IgG2b and IgG2a, mediates phagocytosis. Variant macrophage cell lines selected for the loss of phagocytosis through the IgG2b receptor no longer phagocytize IgG1 bearing SRBC. Monomeric IgG1 did not bind to either macrophage lines or primary macrophages. We conclude from these experiments that antigen-activated IgG1 binds to the same receptor as IgG2b.
Ly phenotype of lymphocytes producing murine migration inhibitory factor (MIF).
Authors: Kühner A L , Cantor H , David J R 
Published: December 2022

Abstract
Murine lymphocytes from lymph nodes or peritoneal exudates were tested after treatment with various anti-Ly sera plus complement for their ability to produce MIF in response to stimulation with either antigen or mitogen. When remaining cells in the LN and PEC were stimulated with either Con A or PPD, respectively, it was found that cells of the Lyl set were primarily responsible for MIF production by T cells. This does not rule out the possibility that, under certain circumstances, other T cell sets may produce MIF or material with similar properties after stimulation by antigen.
Alteration of apparent specificity of monoclonal (hybridoma) antibodies recognizing polymorphic histocompatibility and blood group determinants.
Authors: Mosmann T R , Gallatin M , Longenecker B M 
Published: December 2022

Abstract
The fine specificity of five mouse anti-chicken monoclonal antibodies was altered by changes in pH or temperature. Four of these antibodies recognized determinants of the MHC, and the fifth recognized another polymorphic erythrocyte antigen. The pH changes could alter a monoclonal antibody specificity from an apparently private determinant to an apparently public determinant. These alterations have been interpreted on the basis of the pH effect on binding affinity, relative to the threshold of the assay used. Consistent with this interpretation was the observation that bound antibodies were eluted most rapidly from a "cross-reacting" antigen, even at a pH where cross-reactions were strongest. Also, an increase in the valency of the monoclonal antibody resulted in an increase in the observed degree of cross-reaction. This was demonstrated in a highly multivalent antibody-directed rosette assay (ADRA), where the cross-reactions occurred over a wider pH range. These results have considerable importance for the use of monoclonal antibodies as monospecific reagents, especially in highly polymorphic systems such as the MHC. Also, these results suggest ways to improve the apparent specificity of particular monoclonal antibodies, e.g., by removing undesirable cross-reactions.
Feedback suppression: phenotypes of T cell subsets involved in the Ly1 T cell-induced immunoregulatory circuit.
Authors: McDougal J S , Shen F W , Cort S P , Bard J 
Published: December 2022

Abstract
Ly1 inducer t cells (Ly1:SI) activate resting T cells to generate potent suppressor activity. Primed Ly1:SI generated in vitro were assayed for suppression induction in cultures containing B cells and various Lyt T cell sets that had been positively and/or negatively selected using alpha Lyt sera. These experiments both reaffirm the previously reported requirement for an Ly123 T cell in suppression by Ly1:SI and implicate a third T cell subset, which is absolutely required for the full expression of Ly1:SI-induced feedback suppression. This subset of T cells has the cell surface phenotype, Ly1- Ly23+ 1J+ Qa-1-.
Human endothelial culture supernatant (HECS): a growth factor for hybridomas.
Authors: Astaldi G C , Janssen M C , Lansdorp P , Willems C , Zeijlemaker W P , Oosterhof F 
Published: December 2022

Abstract
Human endothelial culture supernatant (HECS) had strong growth-promotion activity for hybridoma cells: the yield of hybridomas after fusion was increased at least 2-fold over that in the presence of feeder cells, such as mouse macrophages and spleen cells. Moreover, HECS could substitute for feeder cells when hybridomas were cultured at the single-cell level, and strongly enhanced the proliferation of hybrid cells. furthermore, the presence of human endothelial cells prolonged the stability of human-mouse hybridomas, producing human immunoglobulin, hybrids known to survive poorly during culture in vitro.
Purification of immunologically functional subsets of human Ia-like antigens on a monoclonal antibody (Q5/13) immunoadsorbent.
Authors: Quaranta V , Walker L E , Pellegrino M A , Ferrone S 
Published: December 2022

Abstract
Serologic and immunochemical asays have shown that the monoclonal antibody Q5/13 recognizes an antigenic determinant expressed on a subset of human Ia-like antigens. Testing with a panel of HLA typed B lymphoid cells has shown that this determinant is different from those defining the serologic polymorphism of HLA-DR antigens. The monoclonal antibody Q5/13 has been used to purify subsets of human Ia-like antigens, which are immunologically functional. These reagents should facilitate the characterization of structural and functional properties of human Ia-like antigens.
Effect of dextran-S (alpha, 1-3 dextran) on the growth of plasmacytomas MOPC-104E and J558.
Authors: Bhoopalam N , Heller P , Meyerstein N , Hall L 
Published: December 2022

Abstract
The murine plasmacytomas MOPC-104E and J558 secrete IgM-lambda and IgA-lambda, respectively, which are antibodies to alpha, 1-3 dextran, a constituent of dextran-S (DEX-S) extracted from Leuconostoc mesenteroides. A single i.p. injection of 10 microgram DEX-S into BALB/c mice from 7 days before and up to 3 days after the implantation of 5 x 10(3) plasmacytoma cells protected the BALB/c mice from developing the tumors. Immunization with other antigens, such as Escherichia coli lipopolysaccharide, inulin (alpha, 1-6 linkage), and dextran T-10 (no known alpha, 1-3 linkages) did not protect the mice from developing the tumors. Growth of LPC-1 was not affected by DEX-S. The mechanism of this growth inhibition is unknown. It does not appear to depend solely on binding of antigen to tumor cells, and the limits of the effective time intervals between antigen and tumor injection suggest dependence on the presence of antibody to alpha-1,3 dextran.
Differences in the characteristics of inhibition of lymphocyte stimulation by 25-hydroxycholesterol and by the immunoregulatory serum lipoprotein LDL-In.
Authors: Curtiss L K , Edgington T S 
Published: December 2022

Abstract
Suppression of peripheral blood lymphocyte phytohemagglutinin-stimulated 3H-thymidine uptake in vitro by serum lipoprotein fractions enriched in the immunoregulatory low density lipoprotein (LDL-In) and by 25-hydroxycholesterol was compared to determine whether the biologically active constituent of LDL-In might be an oxygenated sterol. Dose titrations indicated that 25-hydroxycholesterol was 100 times more potent than LDL-In on the basis of total sterol. Both were similar in that maximal inhibitory activity was evident when they were present in the cultures for at least 24 hr before mitogen stimulation. However, the suppression of 3H-thymidine uptake by 25-hydroxycholesterol required the continuous presence of the sterol, whereas equivalent suppression by LDL-In was irreversible and did not require the presence of the lipoprotein beyond the preincubation period. 25-Hydroxycholesterol-mediated suppression of 3H-thymidine uptake was mitigated by the addition of cholesterol or mevalonic acid to the lymphocyte cultures, consistent with an effect on sterol biosynthesis, whereas, LDL-In mediated suppression was not. Finally, when chloroquine was used to inhibit lymphocyte lysosomal hydrolysis, which is required for the intracellular degradation and release of cholesterol esters from internalized low density lipoprotein, the phenotypic expression of LDL-In mediated suppression was not altered, indicating that this known pathway of regulation of cellular function by low density lipoproteins is not the primary mode of action of LDL-In. These data indicated that the mode of suppression of mitogen-stimulated thymidine uptake by serum lipoprotein fractions enriched in LDL-In differs from that produced by 25-hydroxycholesterol, and that LDL-In suppression does not appear to result from inhibition of intracellular cholesterol biosynthesis.
In vitro induction of human cell-mediated cytotoxicity directed against herpes simplex virus-infected cells: characterization of the effector lymphocyte.
Authors: Rola-Pleszczynski M 
Published: December 2022

Abstract
Normal human peripheral blood mononuclear leukocytes (PBML) were incubated (sensitized) in vitro for 6 days with herpes simplex virus type 1 (HSV-1)-infected cells. The sensitized PBML were then tested in a 5-hr 51Cr-release microassay against uninfected or HSV-1-infected target cells. PBML subpopulation-depletion studies revealed that the effector cells were neither B cells nor monocytes, but that their activity was found both in the E-rosetting and the non-E-rosetting lymphocyte fractions. Further separation techniques showed that the effector cells in either fraction expressed an Fc receptor for IgG. In vitro-generated, virus-specific cytotoxic activity thus appeared to be mediated both by a T gamma cell and a special null cell, suggesting possible NK cell involvement.
Characterization of cloned murine cytolytic T cell lines.
Authors: Engers H D , Collavo D , North M , von Boehmer H , Haas W , Hengartner H , Nabholz M 
Published: December 2022

Abstract
Murine cytolytic T lymphocytes can be kept in continuous culture apparently indefinitely by repeated passage in a concanavalin A-induced growth promoting medium. Some of these long-term cell lines maintain their cytolytic activity. Starting from three such populations, several cloned cytolytic T cell lines were derived and subsequently subcloned one or more times. Considerable variation in the levels of cytolytic activity was observed between different subclones; some initially active subclones lost activity with prolonged culture. In addition, one of the clones appeared to progressively lose the relative specificity demonstrated during the earlier passages of the parent cell line.
Antigenic determinants of influenza virus hemagglutinin. V. Antigenicity of the HA2 chain.
Authors: Brown L E , Dopheide T A , Ward C W , White D O , Jackson D C 
Published: December 2022

Abstract
All the polypeptide fragments obtained by cyanogen bromide cleavage of the hemagglutinin from A/Memphis/102/72 influenza virus were examined for their ability to bind to IgG raised against purified virus. Within the hemagglutinin heavy chain the only fragment displaying antigenicity is HA1CN1, which comprises the amino-terminal 168 amino acid residues. By the use of a sensitive radioimmunoassay in which the antigen is unlabeled, it was shown that the light chain is also antigenic. Inhibition studies have localized the activity to the HA2CN1 region, which comprises the carboxy-terminal 90 amino acids. The determinant on HA2 is shown to be subtype specific.