bluuebunny/crossref_metadata_2025 huggingface dataset:
LIGAND-INDUCED MOVEMENT OF LYMPHOCYTE MEMBRANE MACROMOLECITLES
Authors: Karnovsky Morris J. , Unanue Emil R. , Leventhal Monika
Published: June 2004

Anti-immunoglobulin (Ig) coupled to ferritin or hemocyanin was used to map the distribution of Ig molecules on lymphocytes derived from bone marrow (B lymphocytes) by freeze-etching. The labeled anti-Ig was distributed all over the membrane in the form of random interconnected patches forming a lacy, continuous network. This was the pattern of lymphocytes labeled at 4°C with the anti-Ig. After warming at 37°C, the labeled molecules concentrated into a single area of the cell (forming the cap) and were rapidly internalized in small vesicles Freeze-etching showed close packing of the labeled molecules in the cap area. There was evidence that in the cap area the Ig molecules were exfoliated from the plane of the membrane, suggesting that the Ig may be superficial to the bilipid layer, or weakly anchored to the membrane.

Similar studies were made using antibodies to histocompatibility antigens. Thymocytes were labeled with anti-H-2 and ferritin anti-Ig at 4°C. Freeze-etching showed large patches scattered over the membrane and separated from each other by several thousand angstroms. This distribution may, in part, explain why H-2 antigens do not readily form a cap; the large patches are beyond the reach of even a double ligand (sandwich) reaction.

The antigens that reacted with heterologous anti-lymphocyte globulin (ALG) were found in small noninterconnected clusters a few hundred angstroms apart. Such clusters presumably cannot be linked by a single antibody but can by a sandwich (ligand to ligand-antigen) reaction. In previous studies it was found that ALG antigens form a cap only after a sandwich reaction. Finally, the receptors for concanavalin A (Con A) were found in a lacy, irregular interconnected, random network. The spatial distribution of these moieties on the membrane may, in great part, determine their movement after reaction with one or two ligands.
VARIATIONS IN THE RESPONSES OF C57BL/10J AND A/J MICE TO SHEEP RED BLOOD CELLS
Authors: Silver Donald M. , McKenzie Ian F. C. , Winn Henry J.
Published: June 2004

In response to repeated injections of sheep red blood cells, C57BL/10J mice produce predominantly 19S antibody in increasingly higher amounts, while A/J mice initially produce 19S antibody and then switch to produce increasing 7S antibody titers. In an F1 generation all mice responded like the C57BL/10J mice. Backcross data implied genetic control involving at least three loci.
HISTOCOMPATIBILITY STUDIES IN A CLOSELY BRED COLONY OF DOGS
Authors: Rapaport F. T. , Watanabe K. , Cannon F. D. , Mollen N. , Blumenstock D. , Ferrebee J. W.
Published: June 2004

17 Cooperstown beagles of known DL-A genotypes were exposed to supralethal total body irradiation and received a bone marrow allograft from a DL-A-identical donor; 11 littermate and 6 nonlittermate donor-recipient pairs were studied. The recipients are surviving uneventfully for 315, 364, 424, 440, 531, 531, 584, 605, 625, 635, and 649 days in the littermate group and for 211, 279, 280, 368, 479, and 480 days in the nonlittermate group.

The radiation chimeras underwent bilateral nephrectomy and received a kidney allograft obtained from their respective marrow donor within 43–120 days after bone marrow transplantation. The renal allografts are surviving for 191, 200, 221, 234, 313, 349, 361, 377, 378, 405, 441, 444, 482, 557, 580, 581, and 586 days, respectively.

12 of 13 skin allografts obtained from the marrow donor are at present surviving in the recipients for 107, 110, 110, 110, 116, 122, 128, 143, 143, 162, 178, and 199 days, respectively; one graft was rejected at 84 days. In contrast, the radiation chimeras rejected 25 skin allografts obtained from DL-A-incompatible donors within 10.5–21 days (MST = 15.2 days). Skin transplants obtained from DL-A-identical siblings of the bone marrow donors were rejected within 20–36 days (MST = 25.8 days) in recipients of bone marrow cells obtained from littermate donors. Recipients of nonlittermate bone marrow transplants accorded such allografts a prolonged survival time of 27–76 days (MST = 56.2 days).

Prospective selection of genotypically DL-A-identical donor-recipient pairs results in the regularly reproducible long-term survival of bone marrow allografts. The radiation chimeras produced in this manner have developed a donor-specific state of unresponsiveness to kidney and skin allografts. The results are consistent with the existence in the canine species of at least three closely linked genetic systems relevant to transplantation, including DL-A, MLC, and a possible bone marrow transplantation locus.
STUDIES OF THE REGULATORY EFFECTS OF THE SEX HORMONES ON ANTIBODY FORMATION AND STEM CELL DIFFERENTIATION
Authors: Eidinger David , Garrett Thomas J.
Published: June 2004

The primary and secondary immune responses to thymus-dependent and -independent antigens were evaluated in normal male and female mice and in castrated male mice. Both IgM antibody production in the primary response and IgG antibody production in the secondary response were enhanced in females vs. males of equivalent age. Castration of the male converted this animal to a female in terms of responsiveness to the thymus-dependent group of antigens, while inducing equivalent or even greater enhanced responsiveness over the female to the thymus-independent antigen, polyvinylpyrrolidone.

Further characteristics of the changes in lymphoid organs were determined in the castrated animal vs. normal males and females. It was shown that the spleen and thymus became markedly hyperplastic, the organ weights exceeding the female, which in turn were greater than in the male. The enhanced weight of the thymus was shown to be due to increased numbers of cortisone-sensitive cells, the absolute number of cortisone-resistant cells remaining equivalent to normal males and females. Thus, the increased thymic weight of the female also resided in the cortisone-sensitive population. Peripheral lymphocyte counts in castrated animals exceeded both normal males and females. Further experiments in gonadectomized males provided evidence that increased thymic cell activity per se played a role in enhanced response to thymus-dependent antigens, but that a thymic-derived hormone mediated the enhanced effect to the thymus-independent antigen in the castrated animal. The capacity for loss of androgenic hormone-producing tissue to generate enhanced differentiation of stem cells was denoted by experiments in which numbers of spleen colonies and uptake of 59Fe, employed as an index of hematopoiesis 1 wk after reconstitution of lethally irradiated castrated and normal recipients, were enhanced in gonadectomized male animals. Thus, in summary, changes in sex hormone levels exerted a marked influence on immune responsiveness and stem cell differentiation, by increasing numbers of functioning cells, by promoting cellular differentiation, as well as by promoting cellular function via hormonal effects.
ASSOCIATION OF H-2 TYPES WITH GENETIC CONTROL OF IMMUNE RESPONSIVENESS TO IGG (γ2a) ALLOTYPES IN THE MOUSE
Authors: Lieberman Rose , Humphrey William
Published: June 2004

Immune responsiveness to IgG allotypes in the mouse was found to be controlled by an immune response gene Ir-IgG linked to the H-2 locus. This was demonstrated by the analysis of the immune response to BALB/c IgG (γ2a) myeloma proteins in mice of various H-2 types from five different linkage groups of immunoglobulin heavy chains. Antisera were examined for antibodies to idiotypic (Fab) and allotypic (Fc) specificities. No immune response to BALB/c IgG myeloma proteins was found in mice with the same heavy-chain immunoglobulin linkage group as BALB/c but of different H-2 types. In mice with immunoglobulin heavy chains that are different than BALB/c, a high immune response to IgG myeloma proteins was found in H-2 types b, bc, p, r, s, and v; a low response in a, d, k, and q. The Ir-IgG gene is controlled by a dominant autosomal gene.
IMMUNE RESPONSES IN VITRO
Authors: Click Robert E. , Benck Loretta , Alter Barbara J. , Lovchik Judith C.
Published: June 2004

The finding that the relationship of the in vitro and in vivo responses of different strains of mice is under genetic control indicates that at least two mechanisms must operate under in vivo conditions to control 19S antibody synthesis. One is involved in the termination of 19S antibody synthesis; the other has a regulatory role on the magnitude of the response. In light of these findings, various concepts based on other genetically controlled immune responses and on the limiting dilution technique should be reassessed. Furthermore, the suppressive in vivo mechanism may be an important type of control in the resistance or susceptibility to the establishment or maintainance of neoplasms.
REGULATION OF ANTIBODY RESPONSE BY CELLS EXPRESSING HISTAMINE RECEPTORS
Authors: Shearer G. M. , Melmon Kenneth L. , Weinstein Yacob , Sela Michael
Published: June 2004

Spleen cells from immunized and unimmunized mice were either passed over histamine-rabbit serum albumin-Sepharose columns or rabbit serum albumin-Sepharose control columns. The immune response potential of 5 x 106 cells excluded from the two columns were compared with each other, and with an equal number of unfiltered cells by injection of the cell suspensions mixed with sheep erythrocytes into irradiated, syngeneic recipients. The direct and indirect anti-sheep erythrocyte plaque-forming cell responses generated by the cells passed over the histamine-bead column were significantly greater than the responses resulting from the inocula of unfiltered cells or cells passed over control columns. These results indicate the existence of a cell population expressing surface receptors for histamine, which functions to regulate antibody responses.
THYMUS-DERIVED LYMPHOCYTES PRODUCE AN IMMUNOLOGICALLY SPECIFIC MACROPHAGEARMING FACTOR
Authors: Evans R. , Grant C. K. , Cox Helen , Steele Kathleen , Alexander P.
Published: June 2004

Spleen cells from mice immunized with an allogeneic tumor when cultured with the specific tumor cells release into the supernatant a specific macrophage-arming factor(s) (SMAF) which binds nonspecifically to macrophages from both mice and rats and renders these cytotoxic to the specific tumor cells. SMAF also binds in an immunologically specific way to the target cells. SMAF-treated target cells grow normally in the absence of macrophages but are killed in the presence of normal macrophages. Thymus-derived cells are necessary for the production of SMAF since (a) after treatment with anti-θ serum immune spleen cells fail to release SMAF; (b) spleen cells from immunized T cell-deprived mice (thymectomized as adults followed by whole body irradiation and restored with bone marrow) fail to produce SMAF on stimulation with the specific target cells. While SMAF has the properties of a cytophilic antibody, it does not belong to one of the established classes of immunoglobulin since high activity is found after column separation in a fraction having a molecular weight between 50,000–60,000 daltons.
LEUKOCYTE-DEPENDENT HISTAMINE RELEASE FROM RABBIT PLATELETS
Authors: Benveniste Jacques , Henson Peter M. , Cochrane Charles G.
Published: June 2004

We have studied the leukocyte-dependent mechanism of histamine release (LDHR) from rabbit platelets, a complement-independent mechanism which has been implicated in the deposition of immune complexes in acute serum sickness of rabbits. It was found by chromatography and passive transfer of serum from immunized rabbits that the antibody responsible for the LDHR was of IgE type. By electron microscope study of the reaction, the leukocyte involved in agglutination of platelets and release of their histamine content was identified as the basophil. Upon addition of antigen, basophils sensitized with IgE degranulated, released their histamine content and a platelet-activating factor (PAF) that caused aggregation of platelets and release of their histamine. Conditions of preparing and preserving PAF activity and some properties of this factor have been elucidated. LDHR must, therefore, be considered as an immediate hypersensitivity-type mechanism which may link allergic reactions with immunologic disease associated with severe structural injury.
SEROLOGICALLY DEFINED AND LYMPHOCYTE-DEFINED COMPONENTS OF THE MAJOR HISTOCOMPATIBILITY COMPLEX IN THE MOUSE
Authors: Bach Fritz H. , Widmer Michael B. , Bach Marilyn L. , Klein Jan
Published: June 2004

The mixed leukocyte culture (MLC) test is an in vitro model of the recognition phase of the homograft response. For the most part, activation in MLC is dependent on differences of the major histocompatibility complex (MHC). Our present studies in the mouse suggest that activation is primarily associated with differences of genetic regions of the MHC other than those which control the serologically defined (H-2) antigens. These differences do not lead to cytotoxic or agglutinating antibody formation despite extensive immunization; we have called these differences lymphocyte-defined (LD) differences. The strongest stimulation in MLC is associated with differences of the Ir region. It is possible that the Ir product is the T cell receptor and that it is this same molecule which can act as the stimulatory agent in MLC. Other possibilities are discussed.
FUNCTIONAL MATURATION OF THYMIC LYMPHOCYTE POPULATIONS IN VITRO
Authors: Mosier Donald E. , Pierce Carl W.
Published: June 2004

Mouse thymocytes were cultured for short periods of time either alone or with one of two supporting cell populations, splenic adherent cells or thymic epithelial cells. The thymus-derived (T) cell activity of thymocytes cultured on supporting cell populations increased dramatically during 2 days of culture, as assayed in the mixed lymphocyte interaction (MLI), response to phytomitogens, and helper cell activity in the in vitro antibody response. The level of activity attained was equal to that of spleen and lymph node lymphocytes and greater than that of steroid-resistant thymocytes. The cultured thymocytes had surface antigens characteristic of mature T lymphocytes with regard to θ and H-2. The appearance of functionally active lymphocytes in vitro depended upon cell division. Most of the active cultured cells arose from cells already undergoing maturation, i.e., from cells with reduced θ determinants and increased H-2 determinants. We therefore have generated a population of thymocytes indistinguishable from peripheral T lymphocytes using simple in vitro techniques. The extent to which the production of these active lymphocytes depends upon in vitro differentiation is discussed.
SPECIFIC HETEROLOGOUS ENHANCEMENT OF IMMUNE RESPONSES
Authors: Rubin Arnold S. , Coons Albert H.
Published: June 2004

In short-term cultures of thymocytes from tetanus toxoid-immunized mice, the addition of 1 ng of toxoid generated the release of a soluble factor which was capable of enhancing the immune response to a heterologous immunogen. The addition of supernatants from such cultures to assay cultures of sheep erythrocyte-stimulated normal spleen cells produced a significant augmentation of the hemolytic plaque response. Culture fluid from similar cultures of normal thymocytes or primed thymocytes cultured without the priming antigen were inactive. The enhancing factor was nondialyzable, heat stable (56°C, 30 min), resistant to DNAse and RNAse, but was inactivated by protease. A factor produced by specifically stimulated primed spleen cells had similar characteristics. In toxoid-stimulated, mixed cell cultures containing primed thymocytes or spleen cells and normal spleen cells, tenfold fewer thymocytes than spleen cells were needed to produce a comparable degree of enhancement of the anti-sheep erythrocyte plaque-forming cell response.
STUDIES ON NORMAL AND IMMUNE LYMPHOCYTE TRANSFER REACTIONS IN GUINEA PIGS, WITH SPECIAL REFERENCE TO THE CELLULAR CONTRIBUTION OF THE HOST
Authors: Zakarian Siraik , Billingham R. E.
Published: June 2004

Using guinea pigs of strains 2 and 13 and their F1 hybrids as experimental subjects, various lines of evidence have been obtained that in this species, as in all others tested, the only significant cellular antigens with which donor lymphocytes engage when normal and immune lymphocyte reactions are incited are radiosensitive leukocytes. Constitutive cells of the skin are unimportant.

(a) The intensities of these reactions in irradiated subjects are dependent upon the peripheral leukocyte concentration. When this falls below a certain threshold no reactions are incitable.

(b) Highly leukopenic animals are capable of developing immune lymphocyte transfer (ILT) reactions if normal lymphoid cells of their own genetic constitution are mixed with the putative attacking donor cells, as "supplementing antigen," before inoculation.

(c) Radiation-chimeric strain 13 animals having F1 hybrid leukocytes in their bloodstream give typical ILT reactions when challenged intradermally with strain 13 anti-2 node cells.

Exposure of strain 2 animals to 600 R does not prevent their becoming actively immunized if, 24 hr later, they are injected intradermally with strain 13 lymphocytes. However, this sensitization, revealed by the host's capacity to give delayed hypersensitivity reactions, wanes as leukopenia progresses. On the basis of this and other findings it is argued that the flare-up stage of the NLT reaction in preirradiated hosts is mainly an expression of host sensitivity against the transferred alien cells.

Two unexpected observations have been made in the course of this study: (a) F1 hybrid animals developed what appeared to be a strong delayed hypersensitivity after intradermal inoculation with parental strain lymphoid cells or antigenic extracts prepared from them. (b) If strain 13 guinea pigs which had been sensitized against strain 2 tissue antigens by intradermal injection of lymphocytes 7 days beforehand were inoculated intravenously with strain 2 antigenic extract a significant proportion of the animals developed severe delayed necrotizing reactions, recall flares, at some or all of the healed skin inoculation sites.
NATURE OF THE STIMULATING CELL IN THE SYNGENEIC AND THE ALLOGENEIC MIXED LYMPHOCYTE REACTION IN MICE
Authors: von Boehmer H. , Shortman K. , Adams Ann P.
Published: June 2004

Thymus cells from CBA and BALB/c mice are stimulated by syngeneic peripheral lymphoid cells in a "one-way" mixed lymphocyte reaction. The stimulating cell appears to be a mature B cell.

Spleen cells from neonatal mice and thymus cells or bone marrow cells from adult mice are not able to induce DNA synthesis in syngeneic thymus cells, although they stimulate significantly allogeneic thymocytes. The ability of peripheral B cells to serve as stimulating cell in a syngeneic reaction develops with the age of the animal.

The marginal stimulation of syngeneic thymus cells when 90% pure peripheral T cells were used as stimulating cells indicated that T cells alone were ineffective in stimulating in syngeneic mixed lymphocyte reaction. However they stimulated effective allogeneic thymocytes.

On a cell-to-cell basis, light density splenic lymphocytes stimulated both syngeneic and allogeneic thymocytes better than did more dense lymphocytes.

The data obtained suggest that stimuli other than those responsible for allogeneic stimulation induce proliferation of syngeneic thymus cells under identical culture conditions.
CELL-TO-CELL INTERACTION IN THE IMMUNE RESPONSE
Authors: Cheers Christina , Miller J. F. A. P.
Published: June 2004

Mice primed to horse erythrocytes (HRBC) produced greatly enhanced 3,5-dinitro,4-hydroxyphenylacetic (NNP)-specific indirect plaque-forming cell (7S PFC) responses when given NNP.HRBC but no difference in hapten-specific direct (19S PFC) responses in comparison to non-carrier-primed mice. The effect was carrier specific and could not be produced by simultaneous challenge of rabbit erythrocyte (RRBC)-primed mice with RRBC and NNP.HRBC. When spleen cells from HRBC-primed mice were transferred to irradiated recipients, there was again an enhanced 7S response to NNP.HRBC. The primed spleen cells could be replaced by giving activated thymus cells to HRBC together with normal spleen as a source of B cells. It is concluded that T cells influence not only the amount but also the class of antibody formed by hapten-sensitive B cells.
THE ROLE OF THYMOCYTES AND BONE MARROW CELLS IN DEFINING THE RESPONSE TO THE DINITROPHENYL HAPTEN ATTACHED TO POSITIVELY AND NEGATIVELY CHARGED SYNTHETIC POLYPEPTIDE CARRIERS
Authors: Karniely Yuval , Mozes Edna , Shearer G. M. , Sela Michael
Published: June 2004

An inverse relationship exists between the net electrical charge of immunogens and the antibodies they elicit (1). Results of an earlier study have demonstrated that the net charge phenomenon has a cellular basis, since the immune response potential of murine spleen cells to 2,4-dinitrophenyl (DNP) on a negatively charged synthetic polypeptide carrier was reduced by cell fractionation over negatively charged glass beads, whereas the response to the same hapten on a positively charged carrier was unaffected (14). To verify that the net charge correlation is expressed at the cellular level, spleen cells were fractionated over positively charged poly-L-lysine-coated glass bead columns, and their immunocompetence to DNP on positively and negatively charged carriers was tested by cell transfers in irradiated recipient mice. In this case, the fractionated cells showed reduced response potential to DNP on the positively charged carrier only. Thus, the cellular basis of the net charge phenomenon has been demonstrated for both positively and negatively charged immunogens (for the same specificity) by cell separation techniques over columns of opposite charge.

In order to establish whether the cell population relevant for the charge properties of immunogens was of thymus or marrow origin, thymocytes and bone marrow cells were selectively passed over positively or negatively charged columns and mixed with unfractionated cells of the complementary type. Transfers of the filtered and unfiltered cell mixtures in irradiated recipient mice immunized with DNP on either a positive or a negative synthetic polypeptide carrier indicated that fractionation of thymocytes, but not of marrow cells, correlated with the spleen population. Thus, thymocytes fractionated over negatively charged columns and mixed with unfractionated marrow cells exhibited reduced response to DNP on the negative carrier, but normal responses to DNP on the positive carrier. The opposite result was obtained when thymocytes were passed over positively charged columns. No effect on the anti-DNP response was detected by filtration of bone marrow cells over columns of either charge. These findings indicate that it is possible to distinguish between thymocytes on the basis of their capacity to react with more acidic or more basic surfaces and that a population of thymus-derived cells may recognize immunogens on the basis of their overall electrical charge. No evidence was found by these techniques that marrow-derived cells contribute to the net charge phenomenon.
REGULATION OF DELAYED HYPERSENSITIVITY
Authors: Dwyer J. M. , Kantor F. S.
Published: June 2004

Two potential mechanisms for terminating delayed hypersensitivity (DH) reactions have been examined in desensitized guinea pigs. Lack of macrophage responsiveness to lymphokines was sought as an explanation for the reduced ability of these animals to express delayed hypersensitivity. Skin-reactive factor was injected into the skin of desensitized guinea pigs and a control group of similarly immunized animals. The resulting inflammatory reactions were similar in size and intensity in both groups indicating normal macrophage responsiveness in the desensitized state. Passive cellular transfer of DH responses to desensitized animals was markedly less successful than transfer to normal animals. However, cells from desensitized guinea pigs did transfer DH responsiveness to normal animals. These data support the concept of a humoral suppressant of cellular immunity, perhaps acting as a feedback inhibitor, produced when guinea pigs are desensitized.
IMMUNODEVIATION BY PASSIVE ANTIBODY, AN EXPRESSION OF SELECTIVE IMMUNODEPRESSION
Authors: Vuagnat Philippe , Neveu Thérèse , Voisin Guy André
Published: June 2004

The effect of passively administered IgG1 and IgG2 anticarrier antibodies on the IgG1 and IgG2 antihapten response has been studied.

Guinea pigs were immunized with dinitrophenylated bovine gamma globulin mixed with purified IgG1 or IgG2 antihuman gamma globulin antibodies, i.e., antibodies directed against a limited range of the carrier determinants. Humoral IgG1 and IgG2 anti-DNP antibody contents were assayed at weekly intervals and 4 to 10 days after a booster injection of antigen in saline given on the 12th wk.

The main finding was the sustained suppressive effect of passive IgG1 anti-carrier antibodies on the active IgG1 antihapten response.

This result is compared with the enhancing effect of passive IgG1 antihapten antibodies and is discussed in the light of T cell-B cell and hapten-carrier relationships, leading to the proposal of a regulatory function of the Fc portion of the IgG1 anticarrier antibody, combined with the antigen, on the T cell.
CHARACTERIZATION OF A LYMPHOCYTE FACTOR WHICH ALTERS MACROPHAGE FUNCTIONS
Authors: Nathan Carl F. , Remold Heinz G. , David John R.
Published: June 2004

As reported previously, antigenically stimulated guinea pig lymphocytes elaborate a soluble factor which activates macrophages in the sense of promoting increased adherence, spreading, phagocytosis, and glucose oxidation through the hexose monophosphate pathway. Further studies on the characteristics and kinetics of this substance were carried out. The activating factor could not be distinguished from a previously characterized lymphocyte mediator, migration inhibitory factor (MIF), on the basis of Sephadex G-100 gel filtration, CsCl density gradient centrifugation, or sensitivity to neuraminidase. It was, however, shown to be distinct from two other lymphocyte mediators, chemotactic factor for macrophages and lymphotoxin. The kinetics of activation were further studied. The data suggest that the 3 day period required by macrophages to manifest a response to the activating factor consists of two stages. In the first, requiring 1–2 days, the macrophages are refractory to the influence of activating factor, but undergo changes which render them receptive. In the second, they respond to activating factor with increased cell adherence and glucose oxidation. Once macrophages have been activated, the effect persists in the absence of activating factor for 24 h. Finally, it was shown that activation in unfractionated supernatants followed the same time-course as that in more purified fractions. The data suggests that the activating factor is the same as MIF and that, in vitro, macrophages respond to this substance with migration inhibition before they become sensitive to its activating influence.
ACTIVE SUPPRESSION AS A POSSIBLE MECHANISM OF TOLERANCE IN TETRAPARENTAL MICE
Authors: Phillips S. Michael , Wegmann Thomas G.
Published: June 2004

Previous work has indicated that tetraparental mice, chimeric since the eight-cell stage because of embryo fusion using histoincompatible strain combinations, possess autospecific immune cells and blocking antibodies. Although this phenomenon has been demonstrated in vitro, it may have relevance to the self-tolerance shown by these mice in vivo. The experiments described here indicate that spleen cells from tetraparental mice can block mixed lymphocyte reactions between the two parental cell types, but not between unrelated strains. Furthermore, this suppressive ability is not affected by an otherwise effective treatment of the tetraparental spleen cells with anti-θ antibody and complement. The in vitro experimental system elaborated here should help to characterize the cell type responsible for the suppression.
BINDING OF ANTIGEN BY IMMUNOCYTES
Authors: Bystryn Jean-Claude , Siskind Gregory W. , Uhr Jonathan W.
Published: June 2004

The binding of antigen to cells with antibody on their surface has been studied in a model system consisting of murine myeloma cells (MOPC 315) and DNP conjugates. Specific binding occurred between the DNP groups of DNP conjugates and cell surface immunoglobulin.

Using this model, the binding affinities of multivalent and univalent DNP conjugates were measured directly by equilibrium-binding techniques and indirectly by displacement of bound conjugate with univalent hapten. With both approaches the multivalent conjugate was shown to bind to cells with an avidity 100–300 fold greater than the univalent hapten. Nonspecific binding of unrelated protein and repeated washing of cells was found to markedly dedecrease the specific binding of univalent conjugates, presumably because the relatively weak bonds dissociate readily.
THE LINKAGE OF GENES FOR THE HUMAN INTERFERON-INDUCED ANTIVIRAL PROTEIN AND INDOPHENOL OXIDASE-B TRAITS TO CHROMOSOME G-21
Authors: Tan Y. H. , Tischfield J. , Ruddle F. H.
Published: June 2004

13 independent mouse-human somatic cell hybrid clones derived from ß-propiolactone-inactivated Sendai stimulated cell fusion of human cells with mouse cells were tested for their sensitivities to human and mouse interferon. All of them were protected by mouse interferon and only six of the clones were protected by both human and mouse interferon. Only the six that were protected by human interferon were shown to express the human dimeric form of indophenol oxidase. Complete chromosomal analysis of the clones indicated human chromosome G-21 to be the only human chromosome in common for the six clones which had both phenotypes present. Nine subclones were derived from one of the clones expressing both phenotypes. Eight of the nine subclones were shown to retain both phenotypes, whereas one subclone lost both. Chromosomal analysis of the subclones indicated the loss of chromosome G-21 from the subclone which lost both phenotypes. It is apparent from these findings that the gene(s) for indophenol oxidase (IPO-B) and the gene(s) for the antiviral protein are syntenic and that they are linked to human chromosome G-21.
LEUKOCYTE LOCOMOTION AND CHEMOTAXIS
Authors: Zigmond Sally H. , Hirsch James G.
Published: June 2004

Polymorphonuclear leukocyte (PMN) locomotion and chemotaxis have been evaluated by direct microscopic observation of individual cells in thin slide-cover slip preparations, and also by observations on populations of cells migrating into a Millipore filter. The direct microscopic method used the polarity of the locomoting PMNs (broad, advancing lamellipodium and knoblike constriction at the rear) to record the direction of movement. The Boyden chamber Millipore assay was made more reliable by following the front of cells advancing into the filter, rather than counting the number of cells on the lower filter surface. Special modifications of the Millipore assay were necessary in order to distinguish between influences on rate of locomotion and true chemotaxis.

In both systems the results indicate that under certain conditions leukocytes, and in particular PMNs, release into the medium a factor stimulating locomotion and exerting chemotactic action on PMNs in the vicinity. This cell-derived factor appears not to require serum factors for its release or action.
FORMATION AND FUNCTION OF A COMPLEX OF THE C3 PROACTIVATOR WITH A PROTEIN FROM COBRA VENOM
Authors: Cooper Neil R.
Published: June 2004

The role of C3 proactivator (C3PA) and a factor isolated from cobra venom (CoF) in the formation of a principle able to cleave C3 was investigated. The results clearly demonstrate two modes of interaction of C3PA with CoF. In isolated form, C3PA and CoF were found to form a reversible protein-protein complex in free solution. This complex had some C3 cleaving activity. In the presence of minute amounts of a partially purified normal serum substance, factor D, the C3PA-CoF complex was stabilized and its efficiency in cleaving C3 was greatly increased. Factor D is thus an activator of C3PA. A firm complex composed of C3PA and CoF, and possessing C3 cleaving activity, was also formed by addition of CoF to serum.
LIGAND-INDUCED MOVEMENT OF LYMPHOCYTE MEMBRANE MACROMOLECULES
Authors: Unanue Emil R. , Karnovsky Morris J. , Engers Howard D.
Published: June 2004

Spleen lymphocytes were studied for the movement and interiorization of complexes of anti-Ig-surface Ig. The movement of the complex into a small, compact zone of the cell membrane (forming a cap) was inhibited by drugs that inhibited glycolysis and oxidative phosphorylation, but not by drugs that affected protein synthesis. Dead lymphocytes did not form caps. Freeze-etching techniques revealed that inhibited lymphocytes showed formation of multiple small complexes over the entire cell surface. Inhibitors of glycolysis and of oxidative phosphorylation also inhibited the interiorization and catabolism of radioiodinated anti-Ig. We hypothesize that cross-linking of all the surface Ig triggers the membrane movements that are required to pull the lattice into one zone of the cell.
TERMINATION OF TOLERANCE TO HUMAN GAMMA GLOBULIN IN MICE BY ANTIGEN AND BACTERIAL LIPOPOLYSACCHARIDE (ENDOTOXIN)
Authors: Chiller Jacques M. , Weigle William O.
Published: June 2004

Bacterial lipopolysaccharides (endotoxin) allowed the circumvention of the thymus-derived (T) cell helper function otherwise required for the antibody response in mice to human gamma globulin (HGG). In an analogous fashion, the state of tolerance to HGG, existing at a time when bone marrow-derived (B) cells had lost their unresponsiveness, could be terminated by the injection of both immunogenic HGG and endotoxin, but by neither given alone. However, no effect on tolerance to HGG could be observed when this regimen was followed at a time when B cells were tolerant. After the spontaneous recovery from tolerance in B cells, it seemed that specific priming was occurring in that population. This phenomenon was observed either by the injection of endotoxin and HGG or by the adoptive transfer of cells into irradiated hosts. These data have been discussed in the light of potential autoimmune manifestations that could theoretically follow a simultaneous gram-negative bacterial infection along with a release of self-antigen.
IMMUNOLOGIC REJECTION OF DIETHYLNITROSAMINE-INDUCED HEPATOMAS IN STRAIN 2 GUINEA PIGS
Authors: Dvorak Harold F. , Dvorak Ann M. , Churchill Winthrop H.
Published: June 2004

The morphologic events associated with the immunologic rejection by strain 2 guinea pigs of ascites variants of two lines of diethylnitrosamine-induced tumors have been studied by light and electron microscopy.

Tumor injection sites in the skin of control animals exhibited clusters of viable, actively mitotic tumor cells along with a modest inflammatory infiltrate composed of lymphocytes, macrophages, neutrophils, and rare basophils. In contrast, similar injections of either tumor line in specifically sensitized guinea pigs elicited typical delayed-type skin reactions associated with tumor cell necrosis and a more extensive inflammatory infiltrate including a selective increase in the number of basophilic leukocytes (12%, line 1, or 23%, line 10, of total inflammatory cells). That basophils may have a role in tumor resistance in vivo is suggested by the close anatomic associations observed between basophils and tumor cells, and by the fact that basophils were the only inflammatory cell to demonstrate a relative increase in frequency in the lesions of sensitized as compared with control animals. Moreover, intraperitoneal injection of line 1 tumor in specifically sensitized animals elicited a striking basophilia within 24 h. Unlike macrophages, basophils did not phagocytose tumor cells but did evidence occasional extrusion of granules and frequently exhibited loss of granule staining density, a change that may be related to release of mediator substances.

Electron microscope studies of line 1 tumor rejection in the peritoneal cavities of specifically sensitized guinea pigs demonstrated aggregations of "activated" macrophages, lymphocytes, basophils, and damaged or dead tumor cells. These aggregates, held together by complex interdigitations of macrophage villi, closely resembled those occurring in vitro among peritoneal exudate cells whose migration from capillary tubes was inhibited by migration inhibition factor (MIF). Moreover, cells in these aggregates, as well as macrophages inhibited by MIF in vitro, lacked a normal coating of cell surface material.
DIFFERENTIAL INHIBITORY EFFECTS OF CHOLERA TOXOIDS AND GANGLIOSIDE ON THE ENTEROTOXINS OF VIBRIO CHOLERAE AND ESCHERICHIA COLI
Authors: Pierce Nathaniel F.
Published: June 2004

Natural cholera toxoid appears to act as a competitive inhibitor of cholera enterotoxin and is thus a useful tool for studying the interaction of cholera enterotoxin with cell membranes. Cholera enterotoxin binds to gut mucosa more rapidly than does its natural toxoid. Once binding occurs, however, it appears to be prolonged for both materials. Formalinized cholera toxoid has no inhibitory effect upon cholera enterotoxin. Enterotoxic activity, ability to bind to gut mucosa, and antitoxigenicity appear to be independent properties of cholera enterotoxin.

Natural cholera toxoid does not inhibit Escherichia coli enterotoxin, indicating that although the two enterotoxins activate the same mucosal secretory mechanism they occupy different binding sites in the mucosa. Ganglioside, which may be the mucosal receptor of cholera enterotoxin, is highly efficient in deactivating cholera enterotoxin. By contrast, ganglioside is relatively inefficient in deactivating heat-labile E. coli enterotoxin and is without effect upon the heat-stable component of E. coli enterotoxin. These findings suggest that ganglioside is not likely to be the mucosal receptor for E. coli enterotoxin. Differences in cellular binding of E. coli and cholera enterotoxins may explain, at least in part, the marked differences in the time of onset and duration of their effects upon gut secretion.
DEFICIT OF SPECIFIC THYMUS-DEPENDENT LYMPHOCYTES IN TRANSPLANTATION TOLERANCE IN THE RAT
Authors: Elkins William L.
Published: June 2004

Recovery from adoptively terminated transplantation tolerance was studied by utilizing formerly tolerant rats as donors of lymphocytes in local renal graft-vs.-host reactions (GVHR). The origin of the proliferating lymphocytes in the GVHR was studied by means of sex chromosome markers. A deficit of specifically reactive lymphocytes, while tolerance was in effect, was revealed by the continuing absence of autochthonous specifically reactive cells after tolerance was abolished in adult thymectomized chimeras. The findings are consistent with Burnet's hypothesis of the cellular basis of tolerance, but apply only to the T lymphocytes of donor origin which normally proliferate in these GVHR.
CELL-MEDIATED LYMPHOLYSIS
Authors: Alter Barbara J. , Schendel Dolores J. , Bach Marilyn L. , Bach Fritz H. , Klein Jan , Stimpfling Jack H.
Published: June 2004

The cell-mediated lympholytic capability of mouse spleen cells stimulated in mixed lymphocyte culture is related to the major histocompatibility complex genotype on target lymphocytes. The strain combinations AQR-B10. T(6R) and B10.A(4R)-B10.A(2R) that result in significant mixed lymphocyte culture activation do not mediate cell-mediated lympholysis on sensitizing target lymphocytes; serologically defined regions (H-2K and H-2D) are identical within each combination. H-2K or H-2D region disparity alone does not cause cell-mediated lympholysis. However after mixed lymphocyte culture activation as seen with B10.A-B10.T(6R), a target cell bearing only an H-2K region difference from the effector cell is sensitive to cell-mediated lympholysis. Likewise an H-2D region difference is an adequate target after mixed lymphocyte culture activation of the effector cell in the combination B10.A(2R)-B10.D2.
CELL INTERACTIONS BETWEEN HISTOINCOMPATIBLE T AND B LYMPHOCYTES
Authors: Katz David H. , Hamaoka Toshiyuki , Benacerraf Baruj
Published: June 2004

Several experimental approaches, designed specifically to circumvent the possible contribution of a complicating "allogeneic effect," have been successfully used to answer the question of physiologic cooperative interactions between histoincompatible T and B lymphocytes in antibody responses to hapten-protein conjugates. This was accomplished for in vivo cell transfer studies by using an F1 hybrid host as the recipient of irradiated, carrier-primed T lymphocytes from one parent and 2,4-dinitrophenyl (DNP)-primed B lymphocytes from the opposite strain. Under these conditions, very good T-B cell cooperative interactions were observed to occur between T and B lymphocyte populations derived from syngeneic donors, whereas no cooperative response was obtained when T cells were derived from one parental strain and B cells from the other. Corroborative experiments were performed in a totally in vitro system in which DNP-primed B cells developed good secondary anti-DNP antibody responses in vitro to soluble DNP-keyhole limpet hemocyanin (KLH) when cultured in the presence of irradiated KLH-primed T cells derived from syngenic donors but not from allogeneic donors.

The failure of histoincompatible T and B lymphocytes to effect physiologic cooperative interactions has important implications for our understanding of how such interactions normally occur. The possibility that these results reflect the existence of a "block" of some sort to cell-cell interaction by virtue of the presence of a foreign major histocompatibility antigen on the surface of either cell has been definitively ruled out in the present studies. These observations demonstrate that the gene(s) that conditions the capability for physiologic T-B cell cooperation must be shared in common by the respective cell types, and suggest, furthermore, that this gene (or genes) belongs to the major histocompatibility system of the mouse. These findings, together with other relevant phenomena described previously, have led us to postulate that there exists on the B lymphocyte surface an "acceptor" molecule either for the putative active T cell product or for the T cell itself. The important genetic considerations and the possible sequence of events surrounding the actual T-B cell interaction implied by these postulates are discussed in detail.
REGULATION OF THE ANTIBODY RESPONSE TO TYPE III PNEUMOCOCCAL POLYSACCHARIDE
Authors: Baker Phillip J. , Reed Norman D. , Stashak Philip W. , Amsbaugh Diana F. , Prescott Benjamin
Published: June 2004

The effect of treatment with antilymphocyte serum (ALS) on the magnitude of the plaque-forming cell (PFC) response to Type III pneumococcal polysaccharide (SSS-III) was assessed in athymic nude mice and thymus-bearing littermate controls. Without ALS treatment, the PFC response was slightly higher in nude than in control mice. Treatment with ALS had no effect on the response of nude mice; however, considerable enhancement was noted in thymus-bearing controls. Such enhancement was ALS dose-dependent and demonstrable under conditions in which there was substantial inactivation of thymic-derived "helper" cells required for an antibody response to erythrocyte antigens.

These findings suggest that amplifier and suppressor cells, which have been reported to regulate the magnitude of the antibody response to SSS-III, represent populations of thymic-derived cells (T cells) that are not present in nude mice. The activities of "helper" T cells and regulatory T cells appear to be independent of one another and mediated by separate subpopulations of T cells.
THE LYMPHOCYTE RESPONSE TO PRIMARY MOLONEY SARCOMA VIRUS TUMORS IN BALB/c MICE
Authors: Lamon E. W. , Wigzell H. , Klein E. , Andersson B. , Skurzak H. M.
Published: June 2004

Adult BALB/c mice were injected with Moloney sarcoma virus (MSV) after which the animals' lymphocytes were examined for activity against Moloney leukemia virus (MLV) antigen-bearing target cells at 5-day intervals for 30 days. Lymphocytes from these animals and appropriately matched controls were fractionated into B cell-deficient (primarily T cells) and T cell-deficient (primarily B cells) subpopulations. Macrophages were removed using iron powder and magnetism. The unfractionated lymphocytes, T cells, and non-T cells were then tested in microcytotoxicity tests. Antigen-specific activity was found in the unfractionated lymphocytes from animals that had not yet developed palpable tumors and from regressor animals. The T cells were active just before tumor development and just after regression; however, by day 30 after virus infection (8–10 days after regression) the T cell subpopulation was much less active. The non-T cell subpopulation was also active before tumor development and soon after regression. However, this activity continued to rise after regression and was highest at 30 days. At day 15 (peak tumor size) neither subpopulation was active. The activity was demonstrated to be specific for the MLV-determined cell surface antigen by testing on control target cells that were MLV antigen negative and by comparison of the inhibitory effects with lymphocytes immune to a nonpertinent antigen as well as normal lymphocytes. The non-T cells were tested for activity before and after removal of macrophages with iron powder and magnetism. Such cells were significantly more active after removal of the macrophages. These data demonstrate specific T cell and non-T cell activity in microcytotoxicity tests with a tumor-specific system and strongly suggest that the non-T cell activity described herein is a B cell function.
IN VITRO STUDIES ON STRAIN-DEPENDENT PRODUCTION OF THYMUS-SPECIFIC AUTOANTIBODIES
Authors: Fuji H. , Milgrom F.
Published: June 2004

In vitro cultures of spleen cells (S) from normal 8–10-wk-old DBA/2J mice were shown to develop a small number of plaque-forming cells (PFC) that released antibodies lytic to syngenic and autologous thymus cells as well as to syngenic lymphoma L5178Y cells used as the target in the PFC assay. A marked increase in the number of PFC detectable on L5178Y target cells was demonstrated on day 4 in the cultures of S cells to which syngenic or autologous thymus cells had been added (S+T) at time 0, whereas the PFC detectable on thymus cells in such cultures remained at a level similar to that in S cultures. This suggested that two populations of PFC participated in the observed phenomena. No PFC developed in the culture of thymus cells (T). The addition of the cell-free supernatants of 24-h cultures of T or of L5178Y cells to syngenic S cultures also caused a specific increase in the number of the PFC detectable on L5178Y, which suggested that certain immunogenic factors released from the T cells stimulated the response observed in the S+T cultures.

Antibodies of IgM nature were detected in the supernatants of S+T cultures by means of cytolysis in agar of L5178Y cells. Although such antibodies did not cause lysis of thymus cells, they could be completely removed by absorption with normal adult or fetal thymus cells of syngenic origin. Still, the absorbing capacity of L5178Y was much higher than that of thymus cells. The absorption was more efficient at 4°C than at 22°C, and hardly any absorption occurred at 37°C. The tissue distribution of the antigen under study seemed to be restricted to thymus cells since no other murine tissue cells tested removed the antibodies.

The thymic antigen under study was not restricted to strain DBA/2J and could be demonstrated on thymus cells of all other strains tested. On the other hand, the ability of spleen cells to respond in vitro to this antigen has thus far been observed only in DBA/2J mice. Spleen cells of strains C57BL/6J and NZB/BINJ as well as (DBA/2 x NZB)F1 failed to show any significant increase in the PFC response detectable on the L5178Y target when syngenic thymus cells or DBA/2J thymus cells were added.

An intravenous injection of syngenic thymus cells to DBA/2J mice also caused the appearance in their spleens of PFC detectable on the L5178Y target.

The described in vitro system may provide a good means of studying the cellular basis of generation of self-tolerance and of its breakdown.