bluuebunny/crossref_metadata_2025 huggingface dataset:
Expression of Immunoglobulin Variable Region Antigens on Mouse B Lymphocytes
Authors: Stanislawski M. , Mitard M.
Published: December 2022

Rabbit antibodies prepared against two purified 7S BALB/c myeloma proteins, A2 (γ1, κ) and MOPC 195 (γ2b, κ), and solid-phase absorbed so as to contain only anti-heavy (H) chain specificities bound to 32 to 35% of C57BL/6 lymph node lymphocytes (about 80% of the B lymphocytes). A similar staining frequency was obtained with solid-phase absorbed antibodies to the Fab fragment and the heavy chain of the A2 protein. On the other hand, antibodies to other 7S proteins (MOPC 21 (γ1, κ), J606 (γ3, κ), and MOPC 173 (γ2a,κ)), as well as anti-Fc γ1, anti-Fc γ2a and anti-idiotypic antibodies either failed to bind to the cells, or bound to a small percentage of these. Employing a method of quantitative inhibition of cell-surface-binding capacity, it was found that the surface binding of the anti-A2 and anti-MOPC 195 antibodies was strongly inhibited by the MOPC 104E (µ, λ1) and J558 (α, λ1) proteins. There was also a reciprocal inhibition by the A2 and MOPC 195 proteins. Purified normal serum IgG1 and IgG2a were also strongly inhibitory. However, eight other BALB/c myeloma proteins of various classes were weakly, or noninhibitory. Only the homologous A2 Fab fragment, and H and light (L) chains inhibited the anti-A2 antibodies. The homologous and heterologous Fc fragments were not inhibitory. These results, added to the selective inhibitory behavior of the myeloma proteins, which is unrelated to either their H or L chain isotypic designation, suggest that the antigens involved are localized in H chain the variable region. The findings implicate that the bulk of C57BL/6 lymph node B lymphocytes expresses a surface H chain variable region subgroup antigen that corss-reacts with the A2, MOPC 195, MOPC 104E, and J558 myeloma proteins.
B Cell Heterogeneity
Authors: Quintáns J. , McKearn J. P. , Kaplan D.
Published: December 2022

Male (CBA/N × BALB/c) F1 hybrid mice cannot mount humoral immune responses to thymus-dependent (T.D.) or thymus-independent (T.I.) phosphorylcholine (PC) antigens and to trinitrophenyl (TNP)-AECM-Ficoll and TNP-AECM-dextran. Transplantation of spleen, bone marrow, or neonatal liver cells from BALB/c mice can restore responsiveness to these antigens. Engraftment of spleen and bone marrow cells occurs in unirradiated NBF1 hosts, whereas restoration of PFC responses by neonatal liver cells requires a sublethally irradiated NBF1 recipient. Reconstitution experiments demonstrated that the spleen contains T.D. and T.I. B cell precursors that can respond immediately to antigenic challenge, although the bone marrow contains only mature T.D. B cells and immature cells (progenitor cells) which will restore T.I. responses 2 weeks after transplantation. Neonatal liver cells contain only immature progenitor cells which, after 1 to 2 weeks in the NBF1 recipient, become antigen-reactive cells. In contrast to anti-TNP PFC responses, which are fully restored in all NBF1 recipients of BALB/c neonatal cells, only a fraction of NBF1 mice gain responsiveness to PC antigens. The frequency of successful reconstitutions of T.D. anti-PC PFC responses was higher than T.I. anti-PC responses. Idiotypic analysis in the reconstituted recipients demonstrated that H8 and non-H8 anti-PC PFC were being generated. Evidence is presented to indicate that the reconstitution with neonatal liver cells functionally resembles a limiting dilution assay for immature PC-specific progenitor cells, which include both H8 and non-H8 idiotype specificities in T.D. and T.I. anti-PC responses.
Human Immune Responses to Hapten-Conjugated Cells
Authors: Seldin Michael F. , Rich Robert R. , Dupont Bo
Published: December 2022

Proliferative responses of human lymphocytes primed in vitro to autologous TNP-cells were found to be associated with autologous D-region determinants irrespective of HLA-B locus antigens. Family studies of secondary TNP-conjugate proliferative responses demonstrated a gene dosage effect in this phenomenon. Moreover, co-culture with allogeneic cells did not affect the net TNP-conjugate proliferative responses of primed responder cells, suggesting that HLA-D region preference was due to a requirement for representation of TNP-molecules in association or combination with autologous MHC structures.

Alloantigens were found to influence the sensitization of lymphocytes to autologous hapten-conjugated cells. Co-culture of allogeneic and TNP-modified autologous stimulator cells in primary cultures enhanced the secondary TNP proliferative response. Sensitization of human lymphocytes to allogeneic cells alone did not prime responses to autologous modified cells. However, priming lymphocytes to modified autologous cells potentiated responses to allogeneic cells. The data suggest a complex relationship between responses to alloantigens and modified autologous cells.
Characterization of Lymphocyte-Activating Factor (LAF) Produced by Human Mononuclear Cells: Biochemical Relationship of High and Low Molecular Weight Forms of LAF
Authors: Togawa Atsushi , Oppenheim Joost J. , Mizel Steven B.
Published: December 2022

Human mononuclear cells (MNL) stimulated with Salmonella typhosa endotoxin (LPS), Actinomyces viscosus cell wall extracts, phorbol myristic acetate (PMA), or phytohemagglutinin (PHA) produced a factor that was mitogenic for mouse thymocytes. These agents not only enhanced the production of this mitogenic factor(s) by cultures of MNL enriched for glass-adherent cells, but also by nonadherent cell cultures. However, when the monocyte contamination of the nonadherent cell population was decreased to less than 0.5%, the remaining nonadherent cells did not generate significant thymocyte mitogenic activity, suggesting that either the contaminating monocytes were the cell source of the factor in the nonadherent cell population or that the production of the factor by nonadherent cells was monocyte dependent. The results of biochemical studies support the former possibility as follows: 1). The mitogenic activity produced by both adherent and nonadherent MNL eluted from Bio-Gel P-100 columns with m.w. of 50,000 to 70,000 and 12,000 to 22,000, values that are characteristic of the two forms of lymphocyte activity factor (LAF) produced by human monocytes. 2). The lower m.w. form of “thymocyte mitogenic” activity produced by the adherent as well as nonadherent MNL when characterized further both exhibited the same behavior on Bio-Gel P-100, DEAE cellular and hydroxylapatite. 3). When the lower m.w. LAF was reconstituted with 2% human serum, concentrated and rechromatographed on Bio-Gel P-100, a significant portion of the LAF activity appeared in the 50,000 to 70,000 m.w. range, suggesting that the higher m.w. form of LAF may actually be a complex of the lower m.w. LAF with a human serum component(s).

In conclusion, a small population of contaminating monocytes in a nonadherent MNL population is capable of producing significant amounts of LAF, and LAF may exist free or in association with a component(s) of human serum.
Limiting Dilution Analysis of Alloantigen-Reactive T Lymphocytes
Authors: Ryser Jean-Etienne , MacDonald H. Robson
Published: December 2022

The effect of specific priming with alloantigens on the frequency of cytolytic T lymphocyte precursors (CTL-P) has been investigated. Alloimmune lymphoid cells were obtained from the spleen of C57BL/6 (H-2b) mice primed with DBA/2 (H-2d) tumor cells or from 14-day unidirectional mixed leukocyte cultures (C57BL/6 anti-DBA/2). CTL-P frequencies directed against H-2d alloantigens were estimated by limiting dilution analysis in a sensitive micro MLC system. Under these conditions, an apparent increase of 3 to 4-fold in CTL-P frequency was observed in alloimmune (as compared with normal) C57BL/6 spleen cells. Evidence was obtained suggesting that this increase was specific for the priming alloantigens. A much greater increase in CTL-P frequency (25 to 100-fold) was observed after alloimmunization of C57BL/6 spleen cells in unidirectional MLC. Under the latter conditions, 5 to 20% of the surviving splenic MLC cells could be identified operationally as CTL-P. A similar enrichment in CTL-P frequency was obtained when lymph node, peripheral blood, or thymus cells were cultured 14 days in MLC. These studies provide direct evidence that the pool of specific CTL-P can be expanded after alloimmunization. Furthermore, the very high frequencies observed after in vitro priming indicate that this system should be particularly useful for future studies of the progeny of individual CTL-P.
Evidence that Natural Cytotoxicity and Antibody-Dependent Cellular Cytotoxicity Are Mediated in Humans by the Same Effector Cell Populations
Authors: de Landazuri Manuel O. , Silva Augusto , Alvarez José , Herberman Ronald B.
Published: December 2022

The present study strongly suggests that, in humans, natural killer (NK) activity and antibody-dependent cell-mediated cytotoxicity (ADCC) are mediated by the same effector cell population. This is supported by two different experimental approaches. First, competition for NK effector cells was accompanied by simultaneous inhibition of ADCC activity. Target cells sensitive to NK activity were capable of inhibiting specifically an ADCC assay in cold target competition experiments. Second, specific removal of NK cells on monolayers formed by target cells sensitive to NK activity caused simultaneous depletion of ADCC effector cells. In association with the removal on the monolayers of effector cells for ADCC as well as NK activity, we also found a significant depletion of cells bearing Fcγ receptors.
Virus-Induced Interferon Production by Human Macrophages
Authors: Roberts Norbert J. , Douglas R. Gordon , Simons Ruth M. , Diamond Margaret E.
Published: December 2022

The presence of interferon during viral infection in humans has been associated with the onset of the recovery process. The identity of the cell responsible for production of interferon in response to live virus has not been determined. Human peripheral blood mononuclear leukocytes, highly purified macrophages, and highly purified lymphocytes were exposed in vitro to influenza A virus. Interferon activity was detectable in the supernatant culture fluids of virus-exposed mononuclear leukocytes by 24 hr, was maximum by 72 to 96 hr, and declined thereafter. In each of eight experiments, supernatant fluid of virus-exposed macrophages contained interferon (100 to 800 units/ml, median 200 units/ml), but in none of the experiments was interferon detected in the supernatant fluid of control macrophages or virus-exposed or control lymphocytes. The interferon had characteristics of classical, Type I, interferon, and its activity was neutralized by rabbit antihuman leukocyte interferon globulin. Appearance of interferon activity in the supernatant fluid could not be attributed to cell death with release of preformed material. Adding lymphocytes to macrophages resulted in no increase in interferon activity in supernatant fluids in response to virus exposure, compared to macrophages alone. The results suggest a mechanism by which human macrophages may play an important role in human defense.
Macrophage-Mediated Tumor Cell Killing: Lack of Dependence on the Cyclooxygenase Pathway of Prostaglandin Synthesis
Authors: Shaw James O. , Russell Stephen W. , Printz Morton P. , Skidgel Randal A.
Published: December 2022

Mφ obtained directly from disaggregated murine Moloney sarcomas produced PGE2 and a hydroxy fatty acid derivative as the major products of arachidonic acid metabolism. Mφ-immunoreactive PGE synthetic rates decreased substantially and cytotoxic activity was lost when freshly explanted tumor Mφ were held in culture 24 hr. Such cultured Mφ remained in a partially activated “primed” state, however, wherein the addition of minute (ng) amounts of bacterial lipopolysaccharide (LPS) returned cytolytic activity and PGE synthesis to original levels. Indomethacin-induced blockade of the Mφ cyclooxygenase pathway inhibited PG synthesis by LPS-stimulated, primed Mφ without affecting the return of cytolytic activity. We conclude, therefore, that the production of PG had no direct role in the mediation of tumor cell killing by activated Mφ isolated from these neoplasms.
Characterization of Functional Fc-Receptor Material from Human Lymphoblastoid Cell Lines
Authors: Elliott Bruce E. , Takács Bèla J.
Published: December 2022

A xenogeneic anti-human Fc-receptor serum was prepared by injecting rabbits with Fc-receptor (FcR) material isolated from the NP-40 lysate of an IgM-secreting human lymphoblastoid cell line. By indirect immunofluorescence, the immune IgG (or F(ab′)2 fragment) from such animals reacted with a fraction of normal human peripheral blood leukocytes (PBL), corresponding closely to the proportion of FcR-bearing cells (assessed by immune complex binding), in the same cell population. The anti-FcR serum stained almost all the cells from five surface Ig-bearing lymphoblastoid cell lines, including the original cell line from which the FcR material was obtained, but not the FcR- T cell-like lymphoma, MOLT-4, phagocytic cells, or a granulocyte-like human cell line, K562. When human PBL were incubated with anti-FcR serum, the proportion of rosettes subsequently formed with antibody-sensitized ox erythrocytes (EA) was greatly reduced. The inhibitory activity of the antiserum was removed when it was absorbed with human PBL enriched for EA rosette-forming cells (RFC), but not human PBL depleted of such cells (T cells). The antiserum reacted with a fraction of Ig-bearing lymphocytes in normal mouse spleen and PBL, and with allogeneic activated T cells (30 to 40% FcR+) from irradiated F1 hybrid mice transplanted with parental T cells, but not with normal thymocytes. The determinants recognized by the anti-FcR serum are distinct from serologically detectable β2 microglobulin, HLA, H-2 and Ia-like determinants: a) The anti-FcR serum precipitated from an NP-40 lysate of a human lymphoblastoid cell line (WT-18), material with an apparent m.w. of 46,000 daltons and that appears distinct from Ia molecules or β2 microglobulin. b) The anti-FcR serum did not react with MOLT-4 cells nor with T cells in normal human PBL, mouse spleen, and thymus, although these cells express serologically detectable HLA or H-2 specificities. c) The anti-FcR serum, but not an anti-human Ia-like serum, reacted with normal mouse spleen cells. d) The anti-FcR serum reacted with an FcR+ T cell tumor, but not with an FcR- T cell tumor, both derived from the same AKR lymphoma.
Activation of Human B Lymphocytes
Authors: Dimitriu Alexandra , Haynes Barton F. , Fauci Anthony S.
Published: December 2022

The precursor of the pokeweed mitogen (PWM)-induced anti-sheep red blood cell (SRBC) plaque-forming cell (PFC) in human peripheral blood was characterized. By a variety of purification procedures, it was demonstrated to be a lymphocyte with surface characteristics of a B cell. Furthermore, it was demonstrated to bind to sheep erythrocytes (E) and thus segregated with the E-rosetting T cells when T cell enrichment was performed by differential fractionation of E-rosetting cells. This binding of the PFC precursor to E was blocked by pretreating the lymphocyte with anti-human Ig before E rosetting, indicating that the PFC precursor specifically bound to SRBC by a surface Ig molecule with binding specificity for sheep red blood cell determinants. Hence, the precursor of the PWM-triggered anti-SRBC PFC is a B lymphocyte with surface Ig expressing specificity for SRBC.
Suppression of Adult B Cell Differentiation in Pokeweed Mitogen-Stimulated Cultures by Fc(IgG) Receptor-Negative T Cells from Cord Blood
Authors: Moriya Naoki , Nagaoki Takeshi , Okuda Norihiko , Taniguchi Noboru
Published: December 2022

Unfractionated T lymphocytes from cord blood suppressed adult B cell differentiation into immunoglobulin-producing cells in pokeweed mitogen-stimulated co-culture system. Cord blood T cells were fractionated into T cells bearing Fc receptors for IgG(Tγ cells) and T cells lacking Fc receptors for IgG(Tnon-γ cells) by rosette formation with ox erythrocytes coated by the IgG fraction of rabbit antisera followed by Ficoll-Hypaque gradient sedimentation. Tγ cells from cord blood, even though isolated after the interaction with immune complexes, showed no suppressor activity on adult B cell differentiation, whereas Tnon-γ cells exerted strong suppression to a similar extent to that by unfractionated cord T cells. The suppressor activity on B cell differentiation by Tnon-γ cells as well as by unfractionated T cells from cord blood was completely abrogated by irradiation with 2000 rads. These results indicated that, contrary to suppressor function found in adult T cells, the suppressor activity in cord T cells might be exerted by a T cell subset lacking Fc receptors for IgG(Tnon-γ cells).
Antibody-Dependent Cellular Cytotoxicity Effector Cell Capability among Normal Individuals
Authors: Edwards David L. , Avis Frederick P.
Published: December 2022

Nonadherent peripheral blood lymphocytes (PBL) from 110 normal individuals were evaluated for their capability to mediate antibody-dependent cellular cytotoxicity (ADCC) against rabbit antibody-sensitized chicken erythrocytes (CRBC). Titration of PBL against a constant number of chromium-51 labeled CRBC allowed for construction of dose response cytotoxicity curves where percent chromium release was plotted against the number of PBL. From these curves the maximum degree of lymphocyte-mediated cytotoxicity and the number of lymphoid cells required for 50% of the maximum lymphocyte-mediated cytotoxicity were determined. The results suggested that in this system the cytotoxic capability of PBL from normal individuals was independent of the age and sex of the donor. The cytotoxic capability of PBL was also found to be constant in individuals tested sequentially. However, significant differences were found to exist between different individuals in their capability of mediating ADCC in this system.
A T lymphocyte subpopulation in multiple sclerosis patients bearing Fc receptors for both IgG and IgM1.
Authors: Merrill J E , Biberfeld G , Kolmodin G , Landin S , Norrby E
Published: December 2022

Abnormally low proportions of total T lymphocytes were found in peripheral blood lymphocytes (PBL) of patients with multiple sclerosis (MS) accompanied by high proportions of T lymphocytes with Fc receptors (FcR) for IgG (T gamma cells). Seventy-five percent of the MS patients had greater than 40% T gamma in the T lymphocyte-enriched population. In 6 out of 16 cases, T mu were also elevated. This elevation, however, did not seem to correlated with disease stage. By mixed rosetting and direct observation with an indirect immunofluorescence test, 30 to 50% of the T gamma cells in MS PBL were also shown to bear FcR for IgM. This population bearing FcR for IgG and IgM, designated T gamma mu, was usually found to be 10% or less of the T gamma population in normal controls. The significance of this T gamma mu population for the MS disease process requires further evaluation.
Defective tumoricidal capacity of macrophages from P/J mice: characterization of the macrophage cytotoxic defect after in vivo and in vitro activation stimuli.
Authors: Boraschi D , Meltzer M S
Published: December 2022

Unlike macrophages from responsive mouse strains, peritoneal cells of P/J mice treated in vivo with viable Mycobacterium bovis, strain BCG, or killed Corynebacterium parvum fail to develop tumoricidal activity. P/J macrophages treated in vitro with lymphokine-rich supernatants, bacterial endotoxic lipopolysaccharides (LPS) or T cell mitogens also fail to develop cytotoxic activity. Experimental manipulation of effector:target cell ratios, doses of activation stimuli, or tumor target cells did not evoke cytotoxic activity. The macrophage defect of P/J mice appeared similar to that of lipid A-insensitive C3H/HeJ mice. The macrophage defect of C3H/HeJ mice is controlled by a gene identical or closely linked to the Lpsd gene. Tumoricidal defects of P/J macrophages, however, appeared independent of the Lpsd gene: responses of P/J spleen cells or macrophages to LPS, which are controlled by the Lps gene, were normal. P/J mice therefore represent a distinct and potentially useful genetic probe for characterization of mechanisms in macrophage activation.
Augmentation of delayed-type hypersensitivity by vesicular stomatitis virus infection in mice.
Authors: Katsura Y , Takaoki M , Kono Y , Minato N
Published: December 2022

Effects of the infection with vesicular stomatitis virus (VSV) on delayed-type hypersensitivity (DTH) to heterologous erythrocytes were investigated in mice. Infection at the time of immunization resulted in production of high levels of DTH that were specific to the antigen used for immunization. The high level of DTH produced in VSV-infected mice could not be attributed to the nonspecific enhancement of the footpad swelling with the infection. Augmentation of DTH was observed in all strains of the mouse (CBA, BALB/c, C3H/He, and C57BL/6) used. The augmenting effect of VSV infection was not as apparent in adult thymectomized mice in which the level of VSV-replicating T cells was reduced. These results strongly suggest that DTH-mediating T cells are resistant to infection by VSV, and also that there are VSV-sensitive cells that may be engaged in the suppression of DTH. It seems improbable, however, that the cells sensitive to VSV infection represent the suppressor cells themselves, since the enhancing effect was not observed in mice in which the suppressor cells were induced by the administration of high doses of the antigen.
Macrophages and T cells control distinct phases of B cell differentiation in the humoral immune response in vitro.
Authors: Hoffmann M K
Published: December 2022

The differentiation of B cells in the in vitro PFC-response to red blood cell antigen proceeds through 2 phases. Antigen-reactive B cells acquire the ability to interact with helper T cells in the first phase. This phase is controlled by macrophages through a mediator that they release (Interleukin 1 ([Il-1]). B cells convert into antibody-secreting cells (PFC) in the second phase, which is controlled by helper T cells or by a mediator that they release (T cell-replacing factors [TRF]). This is demonstrated in experiments in which Il-1 increases the number of B cells capable of responding to T cell help. The majority of antigen-reactive B cells reaches that state of differentiation within 40 hr of incubation with Il-1. After this time, the response of B cells depends no longer on the presence of Il-1 but on the presence of T cells or TRF. The presented data suggest that antigen-primed helper T cells (but not unprimed T cells) induce the release of Il-1 by macrophages, thereby also influencing the early phase of B cell differentiation.
H-2-dependent cell-mediated immunity in vivo: delayed-type hypersensitivity and contact sensitization induced by fluorescein isothiocyanate-conjugated cells.
Authors: Domoto D T , Askenase P W
Published: December 2022

Fluorescein isothiocyanate (FITC) was found to be a suitable hapten to study cell-mediated immunity in vivo in mice. Delayed-type hypersensitivity (DTH) footpad swelling reactions were induced and elicited by injection of FITC-conjugated syngeneic spleen cells, and contact sensitivity (CS) was induced and elicited by skin painting with reactive FITC. Cross-reactive specificity between DTH and CS was demonstrated. Thus, DTH induction with FITC-spleen cells (FITC-SC) also led to the ability to elicit CS; and CS induction by skin painting also led to the ability to elicit DTH with FITC-SC. However, the 2 reactions differed in that the ability to elicit DTH induced by subcutaneous immunization with FITC-SC was evanescent, whereas CS induced by skin painting was long lived. Specificity of these reactions was hapten dependent and additionally required homology at the H-2 locus of the major histocompatibility complex. The H-2 specificity requirement was not evanescent.
"Allergic breakthrough" after antigen sensitization: height of IgE synthesis is temporally related to diurnal variation in endogenous steroid production.
Authors: Bargatze R F , Katz D H
Published: December 2022

Mice of the SJL strain normally display the low IgE responder phenotype. In the course of extensive studies on IgE responses with this strain of mice, it because apparent that the magnitudes of IgE antibody synthesis by SJL mice varied after antigen sensitization either alone or in conjunction with exposure to optimal enhancing doses of whole body irradiation. Analysis of the basis for this variability revealed that SJL respond to antigen sensitization by displaying cyclical IgE response curves determined by the time of day the sensitization is carried out. Moreover, when these low responders are converted to the high responder phenotype by low dose irradiation, the time of irradiation determines the magnitude of the IgE response obtained, whereas the time of antigen challenge determines the potential for generating a good response. The diurnal curve of IgE responses in both unirradiated and irradiation-enhanced low responder mice appears to be determined by normal variations in levels of endogenous corticosteroids, as indicated by the correlation between the normal diurnal curve of endogenous steroid production with the cyclical pattern of IgE responses. This apparent effect of endogenous steroid production on IgE antibody synthesis is supported by experiments demonstrating that the normal IgE pattern in both unirradiated and irradiated mice can be perturbed by administration of cortisone at the proper time of day. These results indicate that IgE antibody synthesis displays unique sensitivity to fluctuations in plasma steroid levels and may have significant implications for the role of steroids in the pathogenesis and management of allergic diseases.
Mouse C3b/C4b inactivator: purification and properties.
Authors: Kai S , Fujita T , Gigli I , Nussenzweig V
Published: December 2022

Mouse C3b/C4b inactivator (C3b/C4bINA) was purified approximately 400 times from mouse serum. It is a beta-globulin and consists of 2 disulfide bonded chains of m.w. 60,000 and 35,000. Under nonreducing conditions, its m.w. is 95,000. It cleaves the alpha'-chain of cell-bound C4b into 3 fragments: alpha 2, alpha 3, alpha 4. The alpha 2 fragments remain bound to the cell surface (C4d), and the rest of the molecule (C4c) is released into the fluid phase. In fluid phase, C3b/C4bINA cleaves the alpha'-chain of C4b in a similar manner but only in the presence of mouse or human C4-binding protein (C4-bp). Mouse C4-bp and human C3b/C4bINA do not cleave human C4b, although mouse C4-bp binds to human C4b. This incompatibility suggests that C4-bp and C3b/C4bINA must interact to cleave fluid phase C4b. Mouse C3b/C4bINA also cleaves the alpha'-chain of human C3b in solution into 2 fragments in the presence of human beta 1H. Therefore, it is likely that mouse and human C3b/C4bINA are homologous proteins. A monospecific antiserum to mouse C3b/C4bINA has been prepared in rabbits. By crossed immunoelectrophoresis, this antiserum detects, in addition to the protein described above, a fast beta-globulin with a m.w. of approximately 200,000 and antigenically identical to C3b/C4bINA but enzymatically inactive. This protein could represent a precursor of C3b/C4bINA.
T11: a new protein marker on activated murine T lymphocytes.
Authors: Gately M K , Martz E
Published: December 2022

Murine lymphocytes were activated in vitro in mixed lymphocyte cultures (MLC) or by the addition of the mitogens concanavalin A (Con A), phytohemagglutinin (PHA), or E. coli lipopolysaccharide (LPS). Activated lymphocytes were internally labeled with 35S-methionine and then disrupted by hypotonic lysis. A plasma membrane-enriched fraction was isolated from each cell population, and the 35S-labeled proteins in this fraction were examined by SDS-polyacrylamide gel electrophoresis (SDS-PAGE). An intensely labeled band, the position of which indicated an apparent m.w. of 11,000, was observed when plasma membrane-enriched fractions from MLC- and Con A-activated cells were subjected to SDS-PAGE. In contrast, plasma membrane-enriched fractions from normal spleen cells, LPS-activated cells, PHA-activated cells, and EL4, RDM4, and P815 tumor cells possessed little or none of this protein, which we have designated T11. T11 was not found in the soluble cytoplasmic protein from MLC-activated cells. Hence the presence of T11 in the plasma membrane-enriched fraction from these cells cannot be attributed to contamination by cytoplasmic protein. Removal of T cells from populations of MLC-activated cells by treatment with monoclonal anti-Thy 1 and complement removed T11. These results suggest that T11 may represent a new protein marker on a subclass of activated T lymphocytes.
Interaction of C-reactive protein with artificial phosphatidylcholine bilayers and complement.
Authors: Volanakis J E , Narkates A J
Published: December 2022

We have examined the interaction of C-reactive protein (CRP) with model membranes and complement. Binding of CRP to multilamellar liposomes or unilamellar vesicles of egg-phosphatidylcholine required the presence of lysophosphatide in the bilayer. The binding was Ca++-dependent, could be inhibited by phosphocholine, and resulted in activation of the classical complement pathway. A weak interaction between CRP and agarose was observed, which was also CA++-dependent and could be inhibited by phosphocholine and galactose. In addition, incorporation of galactocyl cerebroside in phosphatidylcholine:lysophosphatidylcholine liposomes enhanced the binding of CRP. Binding constants of 1.9 X 10(-5) M and 7.1 X 10(-5) M were calculated for liposomes containing and lacking the glycolipid, respectively. Furthermore, CRP bound to galactocyl cerebroside-containing liposomes bound approximately twice as much C1q as the same amount of CRP bound to liposomes lacking the glycolipid. We conclude that: 1) An alteration of the normal organization of phosphatidylcholine bilayers is necessary for binding of CRP. 2) The presence of galactosyl residues on the surface of the bilayer enhances the binding of CRP, perhaps through interaction with a putative secondary binding site on the protein.
A human T lymphocyte differentiation marker defined by monoclonal antibodies that block E-rosette formation.
Authors: Howard F D , Ledbetter J A , Wong J , Bieber C P , Stinson E B , Herzenberg L A
Published: December 2022

A new human T cell surface antigen, Leu-5, has been defined using a set of monoclonal antibodies that block rosette formation between T lymphocytes and sheep erythrocytes (SRBC). Four antibodies obtained from 2 different fusions using 2 immunized mouse strains all reacted with the same antigen. All these antibodies gave identical quantitative immunofluorescence (FACS) profiles, all gave the same staining profiles and intensities when used singly or in combinations, and all precipitated the same molecule. The antigen is a single polypeptide chain, 40,000 to 50,000 Mr, and is found on all thymocytes, peripheral T cells, and some null cells, but not on B cells. Leu-5 is a differentiation antigen that decreases in density as thymocytes mature to peripheral T lymphocytes. Thus, the Leu-5+ subpopulations ranked in order of decreasing Leu-5 density are: a subpopulation of subcapsular thymocytes greater than cortical and medullary thymocytes greater than peripheral T cells (cytotoxic/suppressor subset) greater than peripheral T cells (helper/inducer subset). The density distribution pattern of Leu-5 parallels the relative affinity of thymocytes and peripheral T lymphocytes for SRBC. We suggest that Leu-5 is either identical to or closely associated with the human T lymphocyte receptor for SRBC.
Spontaneous lytic activity against allogeneic tumor cells and depression of specific cytotoxic responses in mice infected with Trypanosoma cruzi.
Authors: Hatcher F M , Kuhn R E
Published: December 2022

The ability of cells from mice infected with Trypanosoma cruzi to generate specific as well as nonspecific cell-mediated cytotoxic responses to allogeneic tumor cells was investigated. The capacity of spleen cells from either C3H/He (C3H) or C57BL/6 (B6) mice to develop cytotoxic responses in vitro against P-815 tumor cells was depressed after the 2nd wk of acute infection initiated with 10(3) parasites. However, spleen cell responses in B6 mice sensitized against P-815 were depressed only in those mice infected for 16 to 22 days and were significantly enhanced in mice infected for shorter or longer periods of time. In subsequent experiments, significant cytotoxic activity against P-815 target cells was observed in cells from infected B6 and, to a lesser degree, C3H mice without prior sensitization with the tumor cells. With the use of both P-815 and YAC tumor cell lines in cytotoxicity assays, two phases of apparently nonspecific T. cruzi-induced lytic activity (TILA) were observed after infection: a 1st phase detected within 2 days against YAC target cells, and a subsequent phase detected against both YAC and P-815 target cells at a time dependent upon the number of parasites injected. Other results demonstrated increased cytotoxic activity against P-815 target cells in 2.5-mo-old C3H mice infected with greater numbers of T. cruzi or when older (4.5 to 6.5 mo) mice were infected with 10(3) parasites. Antibodies cross-reactive to tumor cells were not detected in sera from infected mice, suggesting that TILA is an antibody-independent phenomenon. Possible relationships between the phases of TILA and the modification of specific responses generated in infected mice are discussed.
Monoclonal antibodies against a specific surface determinant on malarial (Plasmodium knowlesi) merozoites block erythrocyte invasion.
Authors: Epstein N , Miller L H , Kaushel D C , Udeinya I J , Rener J , Howard R J , Asofsky R , Aikawa M , Hess R L
Published: December 2022

Twelve hybridoma cell lines secreting monoclonal antibodies against Plasmodium knowlesi merozoites have been produced. Antibodies from 3 of the 12 lines agglutinated merozoites. The 2 monoclonal antibodies (13C11 and 16F8) that markedly agglutinated merozoites blocked merozoite invasion of erythrocytes. Of these 2 lines, the one that induced the most agglutination also blocked invasion most effectively. The third monoclonal antibody (53B3) caused minimal agglutination of merozoites and did not block invasion, nor did the other 9 nonagglutinating antibodies. The 2 blocking monoclonal antibodies bound to antigens around the entire surface of merozoites, as demonstrated by immunoelectron microscopy, and precipitated a single biosynthetically labeled protein of apparent m.w. of 250,000. None of the nonagglutinating lines precipitated this protein. Monoclonal antibodies 13C11 and 16F8 reacted with a common antigenic determinant on a Malaysian and a Philippine strain of P. knowlesi in that they blocked invasion and precipitated a 250,000 m.w. protein from both. Sera from immune monkeys also precipitated this 250,000 m.w. protein.
T lymphocyte characteristics in bone marrow-transplanted patients. II. Analysis with monoclonal antibodies.
Authors: de Bruin H G , Astaldi A , Leupers T , van de Griend R J , Dooren L J , Schellekens P T , Tanke H J , Roos M , Vossen J M
Published: December 2022

The relative distribution of T cell subsets, as defined by the monoclonal antibodies OKT, was analyzed in peripheral blood lymphocytes of 8 children after bone marrow transplantation for aplastic anemia. The percentage of peripheral blood lymphocytes binding OKT3 (directed against a common T cell surface antigen and defining most peripheral T cells) reached normal values shortly after transplantation. In 5 patients, lymphocytes binding OKT8 (directed against an antigen present on the suppressor/cytotoxic T cell subset) were found in high proportion, and lymphocytes binding OKT4 (detecting an antigen present on inducer/helper T cells) in low percentage. This resulted in an inverted ratio OKT4/OKT8 compared with that of lymphocytes from normal individuals. In all patients the lymphocytes bound abnormally high amounts of OKT10 (directed against an antigen present on all thymocytes but not on mature peripheral T cells). In the course of time, a trend towards normalization was observed for all parameters investigated; however, the kinetics of the recovery showed a marked heterogeneity. From the analysis of this phenomenon, it is likely that, among other conditions yet unknown, a minimum of 20% of OKT4-positive lymphocytes is required for a normal proliferative response to T cell mitogens in vitro. No other correlation was found between any lymphocyte phenotype, as defined by the OKT antibodies, and proliferative response in vitro. Furthermore, lymphocytes from the patient with chronic graft-vs-host disease (greater than 50% OKT8 positive) failed to suppress the proliferative response to mitogens and antigens of the lymphocytes of the histo-identical bone marrow donor.
Prevention of tolerance induction by simultaneous administration of anti-Lyb3 antiserum with tolerogen.
Authors: Huber B T , Borel Y
Published: December 2022

Lyb3 serves as a triggering receptor on a mature subset of B lymphocytes. To further investigate the nature of the activating signal received by this receptor, we examined its involvement in hapten-specific B cell tolerance induced in vivo with isologous IgG. We obtained the following results: injection of anti-Lyb3 serum simultaneously with low doses of tolerogen prevented tolerance induction in B cells responsive to TD and TI type-1 antigens but failed to influence B cells responding to a TI type-2 antigen. Furthermore, administration of anti-Lyb3 serum did not change the tolerogenic signal to an immunogenic one, allowing B cell maturation into plaque-forming cells. However, it did make the B cell responsive to a subsequent challenge with antigen. This effect is transient, and dependent on the dose of tolerogen. These results are discussed in terms of our knowledge of the mechanism of B cell tolerance.
Stimulation of immunoglobulin biosynthesis in human B cells by wheat germ agglutinin. I. Evidence that WGA can produce both a positive and negative signal for activation of human lymphocytes.
Authors: Greene W C , Goldman C K , Marshall S T , Fleisher T A , Waldmann T A
Published: December 2022

Wheat germ agglutinin (WGA), previously regarded strictly as a nonmitogenic or anti-mitogenic lectin, can under appropriate conditions markedly stimulate in vitro synthesis and secretion of immunoglobulin (Ig) by human B lymphocytes. Stimulation of Ig production by WGA is 1) confined to a narrow lectin dose range (2 to 10 micrograms/ml; 2) abrogated by the simple sugar N-acetyl-D-glucosamine but not by a variety of other monosaccharides; 3) effective only after early additions of WGA within the initial 72 hr of 12-day cultures; 4) detected in the presence of B and T cells but not B cells alone; and 5) polyisotypic in nature, as indicated by augmented synthetic rates of Ig in each of 3 major classes (IgG, IgA, and IgM). With few exceptions, WGA produces equivalent or greater rates of Ig production as obtained in cultures activated with pokeweed mitogen (PWM), a well-recognized T-dependent polyclonal activator of human B cells. Furthermore, periperal blood lymphocytes from select individuals that respond weakly to PWM are markedly stimulated with WGA. In contrast to these stimulatory effects of WGA on Ig production by lymphocytes exposed to low lectin concentrations, addition of WGA in amounts greater than 15 micrograms/ml to PWM-stimulated human lymphocyte cultures produces marked suppression of the expected level of Ig synthesis. These data indicate that varying doses of WGA can produce contrasting stimulatory and inhibitory effects on human B cell metabolism.
The oxidative metabolism of thioglycollate-elicited mouse peritoneal macrophages: the relationship between oxygen, superoxide and hydrogen peroxide and the effect of monolayer formation.
Authors: Cohen M S , Ryan J L , Root R K
Published: December 2022

The oxygen and glucose metabolism of peritoneal macrophages harvested from untreated mice (resident cells) and mice given an i.p. injection of thioglycollate broth (thioglycollate cells) were examined. Thioglycollate cells consumed approximately 3 times as much O2 at rest and during phagocytosis as resident cells, but oxygen reduction products (superoxide and hydrogen peroxide) could be recovered in only minimal amounts despite triggering by phagocytosis or exposure to PMA. Indirect evidence for the formation of oxygen reduction products such as O2- by thioglycollate cells was obtained by observation of the major pathways for glucose oxidation and NBT dye reduction. When thioglycollate cells were allowed to adhere to a glass surface O2- and H2O2 were easily recovered in the extracellular medium with a 20-fold increase above cells in suspension exposed to PMA. This study suggests that thioglycollate-elicited macrophages have a vigorous oxidative metabolism but that recovery, and perhaps utilization, of O2 reduction products formed will depend on the conditions of incubation. These events may be significant both for the study of parameters of macrophage "activation" in vitro as well as the function of these cells in vivo.
Regulation by PGE2 of the production of oxygen intermediates by LPS-activated macrophages.
Authors: Metzger Z , Hoffeld J T , Oppenheim J J
Published: December 2022

The regulation by prostaglandin E2 (PGE2) of production of oxygen radicals by bacterial lipopolysaccharide-(LPS) activated macrophages was studied in vitro. A 48-hr incubation of murine thioglycollate-elicited macrophages with LPS (0.1 micrograms/ml) resulted in an enhanced ability of these cells to produce oxygen radicals when challenged with phorbol myristate acetate (PMA). Macrophages incubated for 48 hr without LPS did not produce measurable amounts of oxygen radicals when exposed to this triggering stimulus. Thus, PMA-triggered production of oxygen radicals was the result of macrophage activation by LPS. The PMA-triggered production of oxygen radicals by the LPS-activated macrophages was inhibited when PGE2 (10(-5) to 10(-9) M) was present during the incubation with LPS. Inhibition by PGE2 occurred during the early stages of macrophage activation, since the addition of PGE2 24 hr after LPS no longer inhibited the production of oxygen radicals by the macrophages. This inhibitory effect of PGE2 on the LPS-induced activation of macrophages could be reproduced by cyclic-adenosine-monophosphate (cAMP) agonists, such as isoproterenol and cholera toxin as well as by the cAMP analog dibutyryl-cAMP, suggesting a cAMP-mediated mechanism for the inhibitory effect of PGE2 on macrophage activation by LPS. Previous reports have implicated prostaglandins as mediators of destructive processes associated with chronic inflammation. Our findings suggest that PGE2 may, on the other hand, reduce tissue damage in a chronic inflammatory site by inhibiting the production of oxygen radicals by macrophages activated in the sera.
Adherent spleen cells from mice acutely infected with cytomegalovirus suppress the primary antibody response in vitro.
Authors: Bixler G S , Booss J
Published: December 2022

In the present study, we have demonstrated that the hemolytic plaque response of spleen cells from mice acutely infected with murine cytomegalovirus (MCMV) is suppressed in vitro. Mishell-Dutton cultures established with spleen cells from C57BL/6 mice infected 4 days earlier with 4.2 X 10(3) plaque-forming units of MCMV were found to produce significantly fewer direct plaques upon stimulation with sheep red blood cells than corresponding control cultures. Suppression could not be attributed to a generalized lytic destruction of spleen cells, nor was it produced by addition of virus directly to uninfected spleen cell cultures. However, in cultures containing various mixtures of cells from control and infected mice, the direct plaque response was markedly below the predicted response, suggesting that the uninfected cells were actively suppressed by cells from infected mice. Suppression was dependent on the presence of intact spleen cells, since it was not found in the presence of lysed cells. The capacity of spleen cells from infected mice to mediate suppression was demonstrated in the plastic-adherent subpopulation. Treatment of these cells with anti-thymocyte serum (ATS) and complement did not abolish the capacity to suppress the immune response. Thus, adherent ATS-resistant cells from the spleens of mice acutely infected with MCMV, rather than virus alone, have the capacity to actively suppress the hemolytic plaque response in vitro.
IgE responses in human filariasis. I. Quantitation of filaria-specific IgE.
Authors: Hussain R , Hamilton R G , Kumaraswami V , Adkinson N F , Ottesen E A
Published: December 2022

We have developed a noncompetitive solid phase radioimmunoassay to quantitate human IgE antibodies against soluble adult antigens of Brugia malayi (B.m.), a filarial parasite, in sera of patients with various forms of clinical filariasis in Madras, India. A single reference serum was shown to contain 23 micrograms/ml of B.m.-specific IgE by depletion analysis and was used as a standard serum throughout the study. The levels of specific IgE ranged in the patients sera from 2 to 23,000 ng/ml. When these individuals were divided into clinical groups, the individuals with tropical pulmonary eosinophilia had the highest levels (mean = 8630 ng/ml) and were significantly higher than all the other groups (p less than 0.001). The lowest levels were seen in patients with circulating microfilariae (mean = 30.5 ng/ml). Patients exhibiting lymphatic obstruction (i.e., chronic pathology group) had levels slightly higher than microfilaremics (mean = 68 ng/ml) but were not significantly different (p less than 0.1). Surprisingly, individuals living in endemic areas but who had no clinical signs of filariasis also showed appreciable levels of B.m.-specific IgE (mean = 55 ng/ml). The B.m.-specific IgE represented 0.1 to 48% of the total IgE. High percentages of specific IgE may be responsible for evoking allergic symptomatology in patients with tropical pulmonary eosinophilia.
A mitogenic lactose-binding lectin from the sponge Geodia cydonium.
Authors: Bretting H , Phillips S G , Klumpart H J , Kabat E A
Published: December 2022

Two lectins with affinity for hog A + H blood group substance were extracted from the Mediterranean sponge Geodia cydonium. One, termed Geodia lectin I, was purified to near homogeneity by lactose elution from a column of hog A + H coupled to Sepharose 4B. Geodia lectin I was a glycoprotein (carbohydrate content about 14%) with m.w. of about 60,000 and an isoelectric point of pH 4.4. Subunits of about 15,000 daltons were linked by disulfide bonds. The lectin precipitated with various snail galactans composed entirely of DGal and LGal, to a slight degree with guaran, which has DGal alpha 1 leads to 6 in a terminal nonreducing position, and with blood group substances. Of 42 sugars tested, only lactose, dGal beta 1 leads to 4 DGlcNAc, DGal beta 1 leads to 3DGlcNAc, DGalNAc, inhibited precipitation. In view of the relatively high concentration of those disaccharides that inhibited relative to other lectins, the specificity of interaction is thought to be via beta-linked DGal residues that are part of a more complex combining site. Geodia lectin I was mitogenic for human peripheral blood lymphocytes with an optimal concentration of about 5.6 micrograms/ml if serum was omitted for the first 24 hr of culture to allow "triggering." Fetal calf serum apparently contained a high concentration of substances that inhibited mitogenicity and hemagglutination by Geodia lectin I, presumably by specifically interacting with the binding site.