bluuebunny/crossref_metadata_2025 huggingface dataset:
Production of monoclonal antibodies specific for two distinct steric portions of the glycolipid ganglio-N-triosylceramide (asialo GM2).
Authors: Young W W , MacDonald E M , Nowinski R C , Hakomori S I
Published: June 2004

Two hybrid cell lines were prepared by the fusion of mouse myeloma cells with the spleen cells of BALB/c mice that had been immunized with the glycolipid ganglio-N-triosylceramide (asialo GM2). The specificity of the monoclonal antibodies produced by these hybridomas, one an IgM and the other an IgG3, has been defined by hemagglutination inhibition, complement fixation, and lysis of glycolipid liposomes by antibody and complement. A major determinant recognized by the IgM antibody is the nonreducing terminal N-acetylgalactosamine including the C6 primary hydroxyl group, but excluding the C2-acetamide group of N-acetylgalactosamine, because oxidation with galactose oxidase produced a structure showing only minimal cross-reaction with the IgM but replacement of the N-acetyl group with an N-n-butyryl group produced a glycolipid that reacts with IgM antibody to the same extent as with the unmodified glycoplipd. A major determinant recognized by the IgG3 antibody is the terminal N-acetylgalactosamine including the C2-acetamido group, but excluding the C6 primary hydroxyl group of N-acetylgalactosamine, because replacement of the N-acetyl group with an N-n-butyryl group produced a glycolipid that did not react with the IgG3 antibody; in striking contrast the IgG3 antibody reacted with the C6-oxidized glycolipid as well as with the native glycolipid. Neither antibody reacted significantly with any other natural glycolipids tested including several that are structurally related to asialo GM2 such as ganglioside GM2, ganglio-N-tetraosylceramide (asialo GM1), or ceramide dihexoside. These results indicated that in addition to the fine structure specificity described above both antibodies recognize the nonreducing terminal GalNAc beta 1 leads to 4Gal structure. The strict antigenic specificity of these monoclonal anti-glycolipid antibodies indicates their great potential as specific probes for cell surface studies.
A transmissible avian neoplasm. (Sarcoma of the common fowl) by Peyton Rous, M.D., Experimental Medicine for Sept. 1, 1910, vol. 12, pp.696-705.
Authors: Rous P
Published: June 2004

In this paper is reported the first avian tumor that has proved transplantable to other individuals. It is a spindle-celled sarcoma of the hen, which thus far has been propagated into its fourth tumor generation. This was accomplished by the use of fowls of pure blood from the small, intimately related stock in which the growth occurred. Market-bought fowls of similar variety have shown themselves insusceptible, as have fowls of mixed breed, pigeons and guinea-pigs. The percentage of successful transplantations has been small, but in the individuals developing a tumor its growth has been fairly rapid. Young chickens are more susceptible than adults. The reinoculation of negative fowls has never resulted in a growth. Throughout, the sarcoma has remained true to type. It is infiltrative and destructive. Metastasis has been observed once (to the heart). Experiments to determine whether the growth may be transmitted by cell-fragments have not yet been made. Repeated bacteriological examinations have yielded negative results. In its general behavior, so far as tested, this avian tumor closely resembles the typical mammalian neoplasms that are transplantable.
Suppression of hapten-specific delayed-type hypersensitivity responses in mice by idiotype-specific suppressor T cells after administration of anti-idiotypic antibodies.
Authors: Yamamoto H , Nonaka M , Katz D H
Published: June 2004

Delayed-type hypersensitivity (DTH) responses specific for the phosphorylcholine (PC) hapten were induced in BALB/c mice by immunization with syngeneic peritoneal exudate cells (PEC) coupled with diazotized phenyl-phosphoryl-choline. PC-specific DTH responses were elicited in such immunized mice after footpad challenge with PC-derivatized syngeneic spleen cells. Moreover, PC-immune lymph node cells could passively transfer PC-specific DTH responses to naive BALB/c mice and it was possible to demonstrate that the cells responsible for such passively transferred responses were T lymphocytes. Because the T-15 idiotypic determinant displayed on the TEPC-15 PC-binding myeloma protein is known to be a dominant idiotype associated with anti-PC antibody responses in BALB/c mice, an analysis was made of the effects of anti-T-15 idiotypic antibodies on the induction and expression of murine PC-specific DTH responses. Repeated injections of anti-T-15 idiotypic antiserum, raised in A/J mice by immunization with TEPC-15 myeloma protein, into recipient BALB/c mice both immediately before and after sensitization with PC-PEC virtually abolished the development of PC-specific DTH responses. Although administration of anti-T-15 antiserum effectively inhibited the induction phase of PC-specific DTH responses, these anti-idiotypic antibodies had no suppressive activity at the effector phase of these responses. The inhibition observed with anti-T-15 antibodies was highly specific for the PC hapten, and for PC-specific DTH responses of BALB/c but not A/J mice. Studies were conducted to address the possibility that anti-Id treatment induced suppressor T lymphocytes capable of specifically inhibiting the activity of PC-specific T cells participating in DTH responses. The results demonstrate that idiotype-specific suppressor T cells are, indeed, induced by treatment with anti-Id; moreover, such suppressor T cells, once induced, are highly effective in abrogating both the induction and the effector phases of PC-specific T cell-mediated DTH responses in BALB/c mice.
A hemolytic plaque assay for activated murine T cells.
Authors: Primi D , Lewis G K , Goodman J W
Published: June 2004

In an earlier report, it was shown that murine spleen cells cultured with concanavalin A (Con A) released into the culture supernatants helper and suppressor substances for antibody production. The present communication describes the production of rabbit antisera against culture supernates from Con A-activated spleen cells and their use in a plaque assay for mitogen-activated T cells. The plaque assay, utilizing SRBC to which Staphylococcal protein A had been coupled, the developing anti-supernatant antiserum and guinea pig complement, readily detected secreting T cells. The T-cell nature of the plaque-forming cells (PFC) was established principally by the following: (a) the majority of lymphocytes in the centers of plaques were Thy-1-positive by fluroescence; (b) spleen cells depleted of B cells by incubation in plastic dishes coated with rabbit anti-mouse Ig antibody gave greatly enriched PFC responses; (c) anti-Thy-1 and anti-Lyt-2.2 treatment of spleen cells almost completely depleted PFC; (d) T-cell mitogens (Con A and phytohemagglutinin) but not B-cell mitogens (lipopolysaccharides) induced PFC responses; (e) T cells maintained in culture for 10 d with Con A and T-cell growth factor yielded PFC. Kinetic and dose response studies showed that high doses of mitogen induced rapidly appearing T-PFC and the responses peaked at day 1--2 of culture. Lower doses of mitogen-induced PFC required longer periods of incubation for detection, indicating that cell activation and secretion may be different dose-dependent activities of mitogens. Another noteworthy finding was that the antiserum reacted with surface antigens of T-PFC, indicating that secreted products are expressed on the membranes of T cells, offering the possibility of isolating populations of cells with specific secretory potential. Although the precise nature of the T-cell products detected by the antiserum used in this assay are unresolved, 10% of the target-cell-adherent population from spleen cells of BALB/c mice sensitized to L929 cells formed plaques. This suggests that the antiserum has significant activity against the products of cytotoxic T cells, a finding which accords with the activity of anti-Lyt-2.2 serum against mitogen-induced T-PFC. The method clearly offers new possibilities for the analysis of T cells and their products and should provide an important approach to the clonal analysis of lymphokine production.
Properties of an Fc gamma-binding protein isolated from human leukemic B cells.
Authors: Thoenes J , Stein H
Published: June 2004

A selectively Fc gamma-binding protein was isolated from purified and radioiodinated cell membranes from two cases of B-type chronic lymphocytic leukemia and one case of B-type prolymphocytic leukemia by binding to IgG aggregates, horseradish peroxidase-anti-peroxidase IgG complexes, and sheep erythrocyte membrane sheets densely coated with IgG. This protein could not be isolated from the cell membranes of an Fc gamma-receptor-negative chronic lymphocytic leukemia of the T type or from membranes of human erythrocytes. The Fc gamma-binding protein was efficiently solubilized by a mixture of Na-EDTA and 2-mercaptoethanol, but not with one of these agents alone, indicating that both divalent cations and disulfide bridges are involved in the linkage of the Fc gamma-binding protein to the cell membrane. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the Fc gamma-binding protein revealed an apparent mol wt of 28,000 and in isoelectric focusing it showed an isoelectric point of 5.5. The electrophoretic mobility of the 28,000-dalton protein did not change after reduction and alkylation. It was determined that the NH2-terminal amino acid of the protein was glycine. The isolated protein was unable to agglutinate antibody-coated erythrocytes. These findings suggest that the 28,000-dalton IgG-affined protein was composed to O2-enriched buffer lacking reducing agents, the 28,000-dalton protein aggregated to a 115,000-dalton molecule. The isolated Fc gamma-binding protein proved to be different from C1q or its subunits.
Regulatory mechanisms in cell-mediated immune responses. VIII. Differential expression of I-region determinants by suppressor cells and their targets in suppression of mixed leukocyte reactions.
Authors: Rich S S , David C S
Published: June 2004

The phenotypic expression of I-region determinants on cells producing and responding to MLR suppressor factor (MLR-TsF) was established in these studies. Alloantigen-activated MLR suppressor T cells (MLR-Ts), which produce MLR-TsF bearing gene products of the I-C subregion, were exposed to anti-I subregion sera and complement (C) before in vitro culture for MLR-TsF production. Suppressor activity was prevented by removal of cells bearing I-C determinants, whereas elimination of cells expressing I-A/B determinants had no effect. Interestingly, cytotoxic elimination of cells displaying I-J determinants also prevented MLR-TsF production. Admixture of anti-I-J and I-C antiserum-treated cells for MLR-TsF production failed to reconstitute suppressor activity, indicating that I-C and I-J gene products are expressed on a single population of cells critical to MLR suppression, rather than on distinct interacting subpopulations. Anti-I-C serum activity specific for I-C+ MLR-Ts was removed by adsorption with nylon wool-nonadherent splenic T cells and concanavalin A-activated thymocytes; adsorption with splenic B cells from anti-Thy-1,2 serum and C-treated spleen failed to remove relevant anti-I-C activity. These data suggest that regulatory I-C molecules, like I-J molecules, are preferentially expressed on T lymphocytes. Expression of I-C, or other I-region molecules on responder cell targets of MLR-TsF activity was also investigated. Responder cells were pretreated with anti-I subregion-specific sera in blocking or complement-dependent cytotoxic protocols before addition to MLR with MLR-TsF. Neither blocking nor the cytotoxic removal of cells bearing I-C or other I-region determinants from MLR responder populations interfered with MLR-TsF suppression. Because it has previously been demonstrated that MLR-TsF interacts optimally with activated, I-C syngeneic target cells, blocking and cytotoxic studies with anti-I subregion sera were also performed with responder cells activated by 24 h culture in MLR in the absence of MLR-TsF. Brief MLR-TsF pulse after antiserum treatment generated marked suppression regardless of blocking or absence of cells bearing serologically detected I-region determinants. I-C restricted suppression may thus be mediated not by interaction with I-C-bearing cells, but by target cells which exist in requisite association with populations of I-C+ cells.
Distinct Ir genes for helper and killer cells in the cytotoxic response to H-Y antigen.
Authors: von Boehmer H , Haas W
Published: June 2004

The H-Y-specific cytotoxic T-cell response requires helper cells: cells from bone marrow chimeras B6 X CBA leads to B6, B6 X CBA leads to B10.A (5R), or B6 X CBA leads to CBA are each unable to respond to H-2k male cells. If, however, cells from B6 X CBA leads to B6 or B6 X CBA leads to B10.A (5R) chimeras are adoptively transferred together with cells from B6 X CBA leads to CBA chimeras, H-Y-specific CTL restricted to H-2k can be obtained. Thus, cells from B6 X CBA leads to B6 or B6 X CBA leads to B10.,A (5R) chimeras (restricted to the left end of the H-2b haplotype) can help CTL precursors from B6 X CBA leads to CBA chimeras (restricted to H-2k). The two classes of T cells required for the CTL response to H-Y antigen are controlled by different IR genes. All H-Y-specific CTL obtained from chimeras B6 + CBA leads to B6 X CBA were found to be of B6 origin. This suggests that CTL or their precursors must express antigens encoded in the left end of the H-2b haplotype for interaction with helper cells.
Antigen- and receptor-driven regulatory mechanisms. I. Induction of suppressor T cells with anti-idiotypic antibodies.
Authors: Sy M S , Bach B A , Dohi Y , Nisonoff A , Benacerraf B , Greene M I
Published: June 2004

Delayed-type hypersensitivity (DTH) to the azobenzenearsonate (ABA) hapten can be readily induced in A/J mice injecting ABA-coupled syngeneic spleen cells subcutaneously. To further characterize this T-cell-dependent immunological phenomenon, the effect of passively administered anti-cross-reactive idiotype common to anti-ABA antibodies of A/J mice (CRI) antibodies on the development of ABA-specific DTH was investigated. Animals given daily injections (of minute amounts) of anti-CRI antibodies subsequent to immunization with ABA-coupled cells show significant reduction of ABA specific responses. This inhibition is antigen specific and requires the intact immunoglobulin molecule, as F(ab')2 treatments were ineffective in suppressing the reaction. Investigations of the mechanism of the anti-CRI-induced suppression of ABA DTH revealed that the observed suppression is a result of the activation of suppressor cells. Spleen cells taken from animals which received anti-CRI antibodies were able to adoptively transfer suppression to naive recipients. This suppression was shown to be mediated by T cells, as anti-Thy1.2 plus complement completely abrogated the transfer of suppression. In addition, animals pretreated with low doses of cyclophosphamide were not suppressed by the administration of anti-CRI antibodies. The genetic restriction of anti-CRI-induced suppression was demonstrated. Antibodies to the major cross-reactive idiotype, (CRI) associated with anti-ABA antibodies in A/J mice were unable to suppress the development of DTH to ABA in BALB/c mice (H-2d, Igh-1a). Such antibodies were, however, fully active in suppressing ABA DTH in the allotype-congenic C.AL-20 strain which has an allotype (Igh-1d) similar to that of A/J (Igh-1e) on a BALB/c background, and which produces humoral antibodies with the CRI.
Antigen- and receptor-driven regulatory mechanisms. II. Induction of suppressor T cells with idiotype-coupled syngeneic spleen cells.
Authors: Sy M S , Bach B A , Brown A , Nisonoff A , Benacerraf B , Greene M I
Published: June 2004

Anti-p-azobenzenearsonate (ABA) antibodies, coupled covalently to normal syngeneic spleen cells and then given intravenously to normal animals, were found to be potent tolerogens for delayed-type hypersensitivity (DTH) to ABA. The ability of the antibody-coupled cells to induce tolerance was determined to be a result of the cross-reactive idiotype (CRI+) fraction of the antibodies, because anti-ABA antibodies lacking the CRI+ components when coupled to spleen cells were unable to cause any significant inhibition. Furthermore, genetic analysis revealed that the ability of CRI-coupled cells to inhibit ABA-specific DTH is linked to Igh-1 heavy chain allotype, in as much animals which possess heavy chain allotypes similar to that of A/J were sensitive to this inhibition. Adoptive transfer experiments provided evidence that CRI-coupled cells induce suppressor cells, and spleen cells or thymocytes from animals received CRI-coupled cells were able to transfer suppression to naive recipients. In addition, treatment with anti-Thy1.2 serum plus complement completely abrogated their ability to transfer suppression. Thus, this active suppression is a T-cell-dependent phenomenon. In investigating the specificity of these suppressor T cells, it was found that they functioned in an antigen-specific manner and were unable to suppress the development of DTH to an unrelated hapten 2,4-dinitro-1-fluorobenzene.
Ir gene controlled carrier effects in the induction and elicitation of hapten-specific delayed-type hypersensitivity responses.
Authors: Weinberger J Z , Benacerraf B , Dorf M E
Published: June 2004

The genetic requirements of carrier recognition were examined in the priming and elicitation of hapten specific, T-cell mediated, delayed-type hypersensitivity (DTH) responses. It was shown that nitrophenyl acetyl-poly-(L-glu56-L-lys35-L-phe9) (NP-GLO) could prime for NP responses only in strains of mice which are Ir gene responders to GLO. In contrast to this requirement, NO-GLO could elicit an NP-specific response in NP-bovine gamma globulin primed mice, even in GLO nonresponder strains. Furthermore, the nonimmunogenic molecule, NP-GL, could elicit an NP-specific DTH response in animals primed with NP on an immunogenic carrier.
Functional analysis of T cells expressing Ia antigens. I. Demonstration of helper T-cell heterogeneity.
Authors: Swierkosz J E , Marrack P , Kappler J W
Published: June 2004

We have examined the expression of I-region antigens on functional subpopulations of murine T cells. A.TH anti-A.TL (anti-Ik, Sk, Gk) alloantiserum was raised by immunization of recipients with concanavalin A (Con A) stimulated thymic and peripheral T-cell blasts. In contrast to similar antisera made by conventional methods, the anti-Ia blast serum was highly cytotoxic for purified T lymphocytes. Moreover, it reacted in a specific fashion with T cells having particular functions. Treatment of keyhole limpet hemocyanin (KLH)-primed B10.A (H-2 alpha) T cells with this antiserum plus complement resulted in the elimination of helper activity for B-cell responses to trinitrophenyl-KLH. Inhibition was shown to be a result of the selective killing of one type of helper T cell whose activity could be replaced by a factor(s) found in the supernate of Con A-activated spleen cells. A second type of helper cell required for responses to protein-bound antigens appeared to be Ia-. By absorption and analysis on H-2 recombinants, at least two specificities were detectable on helper T cells; one mapping in the I-A subregion and a second in a region(s) to the right of I-J. In addition, the helper T cell(s) involved in the generation of alloreactive cytotoxic lymphocytes was shown to be Ia+, whereas cytotoxic effector cells and their precursors were Ia- with this antiserum. These results provide strong evidence for the selective expression of I-region determinants on T-cell subsets and suggest that T-cell-associated Ia antigens may play an important role in T-lymphocyte function.
In vitro induction of T-lymphocyte-mediated cytotoxicity by infectious murine type C oncornaviruses.
Authors: Taniyama T , Holden H T
Published: June 2004

We have developed a system to induce oncornavirus-specific secondary cytotoxic response in vitro. When Moloney strain of murine sarcoma virus-immune spleen cells were cultivated with purified infectious Moloney murine leukemia virus (M-MuLV) or with supernates of tissue culture cells containing infectious virus, a virus-specific secondary cytotoxic response directed against type-specific determinant(s) of M-MuLV was generated in vitro, as determined by a 4-h 51Cr-release assay. The effector cells were susceptible to the treatment with anti-Thyl.2 plus complement, but were unrelated to natural killer cells (NK), because they could not lyse some target cells specific for M-MuLV in both the induction phase and the interaction between effector cells and target cells. Furthermore, a product of the env gene of M-MuLV, perhaps gp70, appeared to be responsible for this response, because viruses with recombinations in the env gene between ecotropic M-MuLV and a xenotropic virus failed to induce a response. When infectious M-MuLV was exposed to UV-light at different doses, the ability of UV-treated M-MuLV to induce a secondary cytotoxic response decreased in parallel with infectivity, indicating that infectivity was necessary for the induction of this response.
Integration of a virus membrane protein intothe lipid bilayer of target cells as a prerequisite for immune cytolysis. Specific cytolysis after virosome- target cell fusion
Authors: Morein B , Barz D , Koszinowski U , Schirrmacher V
Published: June 2004

Structural requirements for membrane antigens on target cells to mediate immune cytolysis were studied in a model system with purified membrane proteins from Semliki Forest virus (SFV). These SFV spike proteins were isolated in the form of detergent- and lipid-free protein micelles (29S complexes) or, after reconstitution into lipid vesicles, in the form of virosomes. Both the 29S complexes and the virosomes were found to bind well to murine tumor cells (P815 or Eb). When these cells, however, were used as target cells in complement-dependent lysis or in antibody-dependent cell- mediated cytotoxicity assays in the presence of anti-SFV serum, they were not lysed, although they effectively bound the antibody and consumed complement. The same tumor cells infected with SFV served as positive controls in both assays.

Different results were obtained when inactivated Sendai virus was added as a fusion reagent to the cells coated with either virosomes or 29S complexes. Under these conditions the virosome-coated cells became susceptible to SFV- specific lysis, whereas the 29S complex-coated cells remained resistant. Evidence that the susceptibility to lysis ofvirosome-coated cells was dependent on active fusion and, therefore, integration of the viral antigens into the lipid bilayer of the target cells was derived from control experiments with enzyme-treated Sendai virus preparations.

The 29S complexes and the virosomes partially and selectively blocked the target cell lysis by anti-H-2 sera but not by anti-non-H-2 sera confirming our previous finding that major histocompatibility antigens serve as receptors for SFV. The general significance of these findings for mechanisms of immune cytolysis is dicussed.
Mice whose B cells cannot produce the T15 idiotype also lack an antigen-specific helper T cell required for T15 expression.
Authors: Bottomly K , Mosier D E
Published: June 2004

The X-linked CBA/N defect in B cell function precludes an antibody response to phosphorylcholine (PC). Accordingly, (CBA/N X BALB/c)F1 male mice are unresponsive to PC and lack circulating immunoglobulin bearing the T15 idiotype characteristic of BALB/C anti-PC antibody. In contrast, (CBA/N X BALB/c)F1 female mice respond to PC and greater than 80% of the anti-PC antibody is T15+. No T-cell abnormalities are known to be associated with the CBA/N mutation. These experiments compared the ability of helper T cells from either (CBA/N X BALB/c)F1 male (T15-) or F1 female (T15+) mice to help F1 female B cells respond to PC and to influence the level of T15 expression. The results indicate that although F1 male T cells collaborated with F1 female B cells just as efficiently as F1 female T cells for the total anti-PC response, the percentage of T15 expression induced by F1 male T cells fell dramatically. The (CBA/N X BALB/c)F1 male thus appear to lack a helper T-cell subset required for dominant idiotype production. This helper T cell defect could be repaired by adding F1 female T cells primed to a second carrier to F1 male T cells and restimulating the cell mixture with PC coupled to the antigen used to prime the F1 male cells plus free second carrier. This result implies that conventional helper T cells derived from the F1 male donor can collaborate with a distinct helper T-cell subset from the F1 female donor which recognizes both carrier and idiotype to induce an anti-PC antibody response dominated by the T15 clonotype.
A cell-mediated reaction against glomerular-bound immune complexes.
Authors: Bhan A K , Collins A B , Schneeberger E E , McCluskey R T
Published: June 2004

Lewis rats were given a single i.v. injection of soluble immune complexes containing human serum albumin (HSA) and rabbit anti-HSA antibodies, prepared in antigen excess. This resulted in localization of HSA and rabbit gamma globulin (RGG) in glomerular mesangial regions without producing definite histologic changes. 24 h after the injection of immune complexes, groups of these rats received lymph node cells or T-cell preparations from syngeneic donors sensitized to RGG, HSA, or ovalbumin; another group received no cells. All of these groups and a group of normal control rats were given injections of [3H]thymidine at 18, 27, and 44 h. The animals were killed 48 h after the time of cell transfer. In histologic sections, glomerular abnormalities were found only in some of the animals that had received immune complexes and lymph node cells or T-cell populations from donors sensitized to HSA or RGG; the lesions were characterized by focal and segmental increase in cells in mesangial regions. Autoradiographs revealed significantly greater numbers of labeled cells in mesangial regions and glomerular capillaries in the groups that had received immune complexes and cells from HSA- or RGG-sensitized donors than in any of the other groups. Electronmicroscopic studies suggested that the increase in cellularity in mesangial regions resulted from an influx of mononuclear phagocytes. The findings indicate that cell-mediated reactions can be initiated by the interaction between sensitized T lymphocytes and antigens present in immune complexes within mesangial regions.
The receptor specificity of alloreactive T cells. Distinction between stimulator K, I, and Dr Products and degeneracy of third-party H-2 recognition by low-affinity T cells
Authors: Nagy ZA , Elliott BE
Published: June 2004

The specificity of binding of stimulator-derived H-2 antigens by mixed lymphocyte culture (MLC)-activated T blasts was investigated under conditions of antigen excess. We have shown that the detectable proportion of alloantigen-binding blasts from primary MLC is a function of antigen concentration, and can represent up to more than 90 percent of total blasts, when the antigen is presented in the appropriate form (on mitomycin-treated viable stimulator cells, or membrane vesicles prepared from lipopolysaccharide blasts), and at nonlimiting concentration. Thus stimulator alloantigen-binding directly parallels the proliferative response and is not restricted to a subpopulation of T blasts. However, the marked dependence of the binding on antigen concentration indicates that cells with a wide range of receptor affinities for the stimulating determinants are involved. In view of this possibility, the specificity of binding by these cells was studied. We have demonstrated that stimulator K, I, and D region products are bound by nonoverlapping subpopulations of blasts, the sum of which may represent 93 percent of total blasts. Thus, specific distinction by these cells between different H-2 region products is not affected by the putative heterogeneity in terms of receptor affinities. However, specificity with respect to unrelated H-2 haplotypes is strictly dependent on antigen concentration. A preferential binding of stimulator membrane vesicles occurs at limiting concentrations; whereas the majority of blasts bind stimulator and third- party vesicles equally well at high vesicle concentrations. The binding of both vesicle types is specific in that it can be inhibited with the relevant anti-H-2 sera. Furthermore, stimulator and third-party vesicles seem to compete for binding sites on the same cells, as shown by cold antigen inhibition.

From these results, we propose that there is an imperfect distinction between stimulator and third-party H-2 antigens by the majority of primary MLC blasts. In contrast, highly selected long-term MLC blasts do not bind third-party H-2 antigens at any concentration, and seem to have high affinity for the stimulating antigens.

We conclude that large numbers of clones with low-affinity (cross- reactive) receptors are generated in primary MLC, most of which become eliminated during long-term selection. This implies that the frequency of cells strictly specific for nonshared stimulating determinants must be minute.
The role of natural killer cells and antibody-dependent cell-mediated cytotoxicity during murine cytomegalovirus infection.
Authors: Quinnan G V , Manischewitz J E
Published: June 2004

Definition of the functions by which the cellular immune system contributes to control of cytomegalovirus (CMV) infection should permit determination of the specific defects which result in the increased susceptibility to infection of immunosuppressed individuals. Using a murine model, we studied the cytotoxic lymphocyte response to murine CMV infection. This response was found to be biphasic. The initial phase extended from the 3rd to the 6th d after infection, was not genetically restricted, and correlated to a rise in numbers of natural killer (NK) and antibody-dependent killer (K) cells in spleens. The NK- and K-cell responses were preceded, by 24 h, by a rise in serum interferon levels, and occurred before the time when antibody could be measured in serum by neutralization. NK and K cells appear to develop the capacity for specific recognition of CMV-infected cells and the potential to contribute to control of the acute phase of CMV infection.
T-suppressor cells sensitive to cyclophosphamide and to its in vitro active derivative 4-hydroperoxycyclophosphamide control the mitogenic response of murine splenic B cells to dextran sulfate. A direct proof for different sensitivities of lymphocyte subsets to cyclophosphamide
Authors: Diamantstein T , Willinger E , Reiman J
Published: June 2004

As measured by [(3)H]thymidine uptake, spleen cells of mice injected 7 d previously with a single dose of cyclophosphamide (Cy) (125 mg x kg (-1)) gave an enhanced response to dextran sulfate (DS), a diminished response to lipopolysaccharide (LPS), and a normal response to concanavalin A. Addition of syngeneic thymocytes to spleen cells inhibited the enhanced response of the cells to DS and slightly enhanced their response to LPS. Pretreatment of thymocytes by 4-hydroxyperoxycyclophosphamide (4HP-Cy) in vitro (an in vitro active derivative of Cy) abrogated the effect of thymocytes on the DS response but not on the LPS response. Pretreatment of spleen cells by small doses of 4HP-Cy (0.1-1.0 μg. ml(-1)) in vitro enhanced the capacity of the cells to respond to DS but either did not affect, or even diminished their capacity to respond to LPS. The enhancement of the DS response by 4HP-Cy treatment could not be detected using spleen cells depleted of T cells or lacking functioning T cells. 4HP-Cy doses more than 3 μg ml(-1) diminished or abolished the capacity of the spleen cells to respond to LPS as well as their capacity to respond to DS.

The results show (a) that in contrast to the LPS-reactive B-lymphocyte subset, the proliferative capacity of DS-reactive subset is negatively controlled by a Cy- and 4HP-Cy-sensitive T-cell subset and (b) that these T- suppressor cells are more sensitive to Cy and 4HP-Cy (to their respective active alkylating metabolites) than B lymphocytes and T cells carrying other immunological functions.
Secretory component as the receptor for polymeric IgA on rat hepatocytes.
Authors: Orlans E , Peppard J , Fry J F , Hinton R H , Mullock B M
Published: June 2004

Rat hepatocytes in short-term monolayer cultures bound radiolabeled polymeric rat IgA but not IgG. The binding of 125I-IgA was inhibited equally well by unlabeled polymeric IgA and by antiserum to rat secretory component (SC). The antibody to SC, after specific purification and radiolabeling, was bound to hepatocytes as effectively as the IgA. These results indicate that SC acts as the receptor for polymeric IgA on rat hepatocytes as it does on human gut epithelia, and that the transport of IgA from blood to bile in rats across the liver is analogous to that of IgA across human enterocytes.
Regulation of Fc fragment-induced murine spleen cell proliferation.
Authors: Morgan E L , Weigle W O
Published: June 2004

Murine splenic lymphocytes proliferate in response to supernatant material derived from Fc fragment-pulsed splenic adherent cells. The stimulatory supernatant results from the interaction of Fc fragments with adherent cells or adherent cell supernate. Isolation of the stimulatory material in the supernate by Sephadex chromatography revealed that the mitogenic component was a cleavage product of Fc with a mol wt of approximately 14,000. The spleen cell type responsible for the generation of mitogenic Fc subfragments appears to be a macrophage. Unstimulated macrophages release an active supernate without being exposed to Fc fragments. The supernate of unstimulated macrophages apparently contain an enzyme which is capable of cleaving Fc fragments into the 14,000-mol wt mitogenic molecules. The spleen cell population induced to proliferate in response to the adherent cell supernate is present in T-cell depleted and Sephadex G-10 filtered cell preparations. Depletion of cells bearing immunoglobulin on their surfaces results in a reduced proliferative response to the mitogenic supernatant material indicating that it is probably a B cell.
Role of self carriers in the immune response and tolerance. V. Reversal of trinitrophenyl-modified self suppression of the B-cell response by blocking of H-2 antigens.
Authors: Jandinski J J , Li J , Wettstein P J , Frelinger J A , Scott D W
Published: June 2004

Trinitrophenylated syngeneic spleen cells (TNP-SC) are potent tolerogens of the anti-TNP plaque-forming cell (PFC) response in vivo and in vitro. This unresponsive state requires T cells for both its induction and maintenance. Because H-2K/D-restricted cytotoxic T cells are also induced by exposure to TNP-SC, we determined the role(s) of histocompatibility antigens (K, I, and D) in the suppression of the PFC response by TNP-SC. We treated syngeneic TNP-modified stimulator cells with antiserum directed at K-, I-, or D-region determinants and found that blocking of H-2K or D antigens on TNP-SC transformed these tolerogens into immunogens capable of eliciting an anti-TNP PFC response in the absence of extrinsic immunogens like TNP-polymerized flagellin. In H-2k or H-2a(k/d) mice, only H-2Kk needs to be blocked on the stimulator cells, whereas H-2K or D recognition was apparent in B10.A(4R) mice. These observations indicate that suppression of the PFC response by TNP-SC shows the same restriction in recognition as does the cytotoxic T-cell response. Furthermore, our results suggest that TNP-I-A is recognized by the helper cells in this system as the intrinsic antigen. When both TNP-K and TNP-I-A are present and available on the same stimulator cell, suppression (via modified K recognition) is dominant over help.
T-cell-mediated suppression of anti-tumor immunity. An explanation for progressive growth of an immunogenic tumor.
Authors: Berendt M J , North R J
Published: June 2004

The results of this paper are consistent with the hypothesis that progressive growth of the Meth A fibrosarcoma evokes the generation of a T-cell-mediated mechanism of immunosuppression that prevents this highly immunogenic tumor from being rejected by its immunocompetent host. It was shown that it is possible to cause the regression of large, established Meth A tumors by intravenous infusion of tumor-sensitized T cells from immune donors, but only if the tumors are growing in T-cell-deficient recipients. It was also shown that the adoptive T-cell-mediated regression of tumors in such recipients can be prevented by prior infusion of splenic T cells from T-cell-intact, tumor-bearing donors. The results leave little doubt that the presence of suppressor T cells in T-cell-intact, tumor-bearing mice is responsible for the loss of an earlier generated state of concomitant immunity, and for the inability of intravenously infused, sensitized T cells to cause tumor regression. Because the presence of suppressor T cells generated in response to the Meth A did not suppress the capacity of Meth A-bearing mice to generate and express immunity against a tumor allograft, it is obvious that they were not in a state of generalized immunosuppression.
Induction of acute cholecystitis by activation of factor XII.
Authors: Becker C G , Dubin T , Glenn F
Published: June 2004

Acute, acalculous cholecystitis is seen among patients suffering with bacterial sepsis, burns, trauma, or cancer; clinical conditions that could lead to activation of factor XII-dependent pathways and result in inflammation of the gall bladder. To test this hypothesis, dogs were injected intravenously with ellagic acid or rutin, known polyphenol activators of factor XII, or with Escherichia coli endotoxin, also known to activate factor XII, and monkeys were injected intravenously with ellagic acid. In both species, in vivo activation of factor XII-dependent pathways with polyphenol activator resulted in rapid and selective development of acute vasculitis in the serosa and muscularis of the gallbladder and margination of polymorphonuclear neutrophils in pulmonary blood vessels. Intravenous injection of E. coli endotoxin in dogs resulted in necrosis and thrombosis of vessels that were especially severe in the serosa and muscularis of the gallbladder but also present in vessels of many other organs. These observations indicate that blood vessels of the gall bladder and, to a lesser degree, the lung are especially sensitive to injury consequent to in vivo activation of factor XII-dependent pathways and, in view of the common ingestion of plant polyphenols, may provide important insight into the pathogenesis of cholecystitis in man.
Selection of cytotoxic T-cell precursors specific for minor histocompatibility determinants. I. Negative selection across H-2 barriers induced with disrupted cells but not with glutaraldehyde-treated cells: evidence for antigen processing.
Authors: Korngold R , Sprent J
Published: June 2004

Intravenous injection of CBA mice with H-2-compatible irradiated B10.BR spleen cells led to a sequence of negative and positive selection of the host T-cell response against the multiple foreign minor histocompatibility antigens (HA) on the injected cells. By 1 d posttransfer, thoracic duct lymphocytes (TDL) of the host had lost the capacity to differentiate in vitro into cytotoxic cells specific for the injected minor HA; spleen and lymph node cells, by contrast, gave normal or enriched responses at this time. By 5 d posttransfer, TDL were hyperresponsive to the injected antigens. Selection with disrupted (sonicated) cells gave similar findings. With injection of either irradiated of disrupted spleen cells, the H-2 haplotype of the minor HA-bearing cells had no apparent effect on the magnitude of selection. By contrast, treatment of spleen cells with glutaraldehyde before injection led to H-2 restriction of selection, i.e., negative selection of the CBA response to B10.BR was marked with injection of glutaraldehyde-treated H-2-compatible B10.BR cells but was minimal with H-2-different B10 or B10.D2 cells. These data are taken to imply that, at least in H-2-incompatible situations, the minor HA-bearing cells must be processed by host cells, i.e., to allow the antigens to become associated with self H-2 determinants. Circumstantial evidence from studies on the specificity of selection induced with glutaraldehyde-treated cells from mice of the B10 recombinant strains suggested that I region-restricted T cells may control the induction of H2K, D-restricted cytotoxic precursor cells.
Growth of SJL/J-derived transplantable reticulum cell sarcoma as related to its ability to induce T-cell proliferation in the host. I. Dominant negative genetic influences of other parent haplotype in F1 hybrids of SJL/J mice.
Authors: Katz I R , Lerman S P , Ponzio N M , Shreffler D C , Thorbecke G J
Published: June 2004

Growth of three transplantable reticulum cell sarcomas (RCS) was studied in a variety of F1 hybrids of SJL/J mice by determination of lymph node (LN) and spleen: body weights ratios 7 and 14 d after intravenous injection of RCS cells. Comparison of BIO.S x SJL and A.SW x SJL with SJL/J showed a negative effect of both the A and the BIO non-H-2 genes, particularly on growth in LN. F1 hybrid resistance was noted with F1 hybrids that carried H-2Dd and was much more evident with F1 hybrids from BIO- than from A-background mice. This resistance was less marked at 14 than at 7 d and was partially overcome by injection of higher tumor doses. Changing the I region in the F1 parent from H-2d to H-2b or H-2f had no effect on growth, but changing to H-2k or H-2d virtually abolished the ability to support tumor growth. This effect appeared partially as a result of the I-E/C and partially of the I-A(B) region and was not overcome by higher tumor dose or longer intervals after injection. There also appeared to be a negative influence on growth of H-2Kk, but this was difficult to differentiate from the I-Ak effect with the available strains. The known proliferative responsiveness that SJL/J Lyt-1 T cells exhibit to Ia determinants on gamma-irradiated RCS cells in vitro was also compared with that of cells from various F1 hybrids. Responsiveness of F1 LN cells was expressed as a percentage of the response in SJL/J LN cells to the same RCS cells, measured as [3H]thymidine incorporation. There was a striking degree of correlation between proliferative responsiveness of F1 LN cells to RCS and the ability of the F1 mice to support tumor growth. This correlation was especially clear with respect to the negative influences of non-H-2 genes, and of H-2 loci in the I region, particularly of I-Ak or -d and of I-E/Ck or -d, but there also appeared to be a (smaller) negative effect of I-Ab or -f. Negative influence of H-2Dd on growth, however, was not reflected in a similarly large effect on the proliferative response. Additional findings showed that LN cells from all F1 hybrids exhibited equivalent syngeneic mixed lymphocyte responses in the presence of polyethylene glycol to mitomycin-treated spleen cells from both the SJL/J and the other parent. The extra high response of F1 cells to RCS cells, as compared with SJL spleen cells, however, was always absent when Ik or -d was contributed by one of the F1 parents. The results suggest a promoting effect of the proliferative response on RCS growth in vivo and, furthermore, an interesting effect of I-A and I-E/C genes, possibly via an interaction product, on the ability of LN cells to be stimulated by Ia determinants on RCS cells.
Restriction specificities, alloreactivity, and allotolerance expressed by T cells from nude mice reconstituted with H-2-compatible or -incompatible thymus grafts.
Authors: Zinkernagel R M , Althage A , Waterfield E , Kindred B , Welsh R M , Callahan G , Pincetl P
Published: June 2004

Congenitally thymusless nude mice that lacked functional T cells were reconstituted with H-2-compatible or -incompatible thymus grafts taken from either fetal, newborn, or adult mice and transplanted under the kidney capsule or subcutaneously. Transplantation with unirradiated fetal (15--17 d) or newborn thymus grafts reconstituted the nude mice as assessed by their subsequent generation of virus-specific cytotoxic T cells in vivo or alloreactive T cells in vitro. The restriction specificity of T cells from homozygous mice was exclusively for the nude host H-2, as shown by direct cytolysis or by cold target competitive inhibition assays. irrespective of whether nude mice were reconstituted with H-2-compatible, semiallogeneic, or H-2-incompatible, unirradiated newborn or fetal thymus grafts (in order of decreasing efficiency of reconstitution). The restriction specificity for the nonhost H-2 of the thymus could not be demonstrated even after primary or secondary sensitization in an infected appropriate F1 environment. These nude mice reconstituted with fetal or newborn grafts were tolerant to the H-2 of the thymus donors. Nude mice transplanted with irradiated adult thymus grafts were reconstituted functionally with syngeneic or semisyngeneic but not with allogeneic thymus grafts. In homozygous nu/nu irradiated heterozygous recipients of F1 thymus grafts, the restriction specificity for the nonhost thymic H-2 could not be elicited upon adoptive sensitization in irradiated and infected F1 heterozygote stimulator mice; in fact, these chimeras' lymphocytes were not tolerant to the nonhost H-2. The discrepancy between the restorative capacity of unirradiated vs. irradiated thymus grafts suggests that precursors of T cells in nude mice can acquire restriction specificity and immunocompetence independently of a conventional, functioning H-2-compatible thymus if exposed to an allogeneic fetal or a newborn thymus that contains functioning thymocytes of donor type but not if reconstituted with an irradiated adult allogeneic thymus.
Isolation and partial characterization of the human homologue of Thy-1.
Authors: Ades E W , Zwerner R K , Acton R T , Balch C M
Published: June 2004

A glycoprotein of 25,000 daltons was isolated from a human T lymphoblastoid cell line (MOLT-3). A monovalent antiserum raised against this antigen precipitated mouse Thy-1.1 antigen as well as a 25,000-dalton antigen from human blood T cells. The unabsorbed serum was also cytotoxic for both mouse and human T cells. By multiple criteria, this human T antigen appears to be homologous with mouse Thy-1.
A murine C4 molecule with reduced hemolytic efficiency.
Authors: Atkinson J P , McGinnis K , Brown L , Peterein J , Shreffler D
Published: June 2004

C4 functional activity and antigenic levels were determined in H-2-congenic mouse strains. In strains with the H-2w7 haplotype, the C4 hemolytic activity per unit of residual Ss antigenic activity, after depletion of the nonfunctional Slp-positive molecules was 25-33% that found with other H-2 haplotypes. This reduced hemolytic efficiency was not the result of either a more labile C4 molecule or of the presence of inhibitors. Moreover, other strains with comparable antigenic concentrations of Ss (C4) and Slp has three- to fourfold higher levels of C4 hemolytic activity. Based on these data and previously reported structural differences between C4 molecules from the H-2w7 haplotype compared with other standard H-2 haplotypes, the reduced hemolytic efficiency of this molecule is probably secondary to alterations in the structure of its alpha-chain.