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Biomedical subjects

E Diener

Publications and source records attributed to E Diener.

At least 73 records · Page 4Linked to original sources
PubMed1980

Models for the production of stable hematopoietic chimerism across major histocompatibility barriers in adults.

Experiments presented in this paper indicate that DBA/2J (H-2d) mice parabiosed for more than 100 days to the F1 hybrid between DBA/2J and C3H/HeJ (H-2k) contain in their serum an anti-H-2k antibody that is preferentially reactive with hematopoietic tissue and is also capable of killing C3H/HeJ colony-forming stem cells in vivo (CFU-S). These findings make the antibody a likely participant in the "takeover" reaction, in which DBA/2J red and white cells eventually replace the F1 hybrid blood system. With these observations used as a basis, 10(8) DBA/2J spleen cells were injected along with anti-H-2Kk (anti-host) monoclonal antibody into 10-wk-old (DBA/2J x C3H/HeJ)F1 hybrid hosts. The recipients had a high surivival rate and exhibited long-term chimerism. Unlike the situation in the parabionts, the DBA/2J lymphoid cells in the injection chimeras were found to be unresponsive to C3H/HeJ alloantigens. This could result from the continued presence of F1 hybrid stimulator cells, which are missing in the parabionts. The injection chimeras indicate that one can establish stable chimerism in adult mice without irradiation or metabolic poisoning.

Absorption↗
PubMed1979

Tolerance induction during ontogeny. I. Presence of active suppression in mice rendered tolerant to human gamma-globulin in utero correlates with the breakdown of the tolerant state.

A specific state of T- and B-cell tolerance to human gamma-globulin (HGG) was induced in utero by intravenous administration of the deaggregated antigen to pregnant BALB/cCr mice. Tolerance persisted in the offspring until the 12th-wk of age and then began to gradually disappear. Suppressor cells could only be found when responsiveness to HGG ultimately appeared in the in utero-treated animals but not when they were completely unresponsives. In contrast, HGG-specific suppressors found in animals made unresponsive to HGG as adults appear to be associated with either the establishment and/or maintenance of the unresponsive state. To the extent that these experiments are consistent with natural self-tolerance to a serum protein, we conclude that active suppression is not a prerequisite from maintenance of unresponsiveness to self.

Animals↗
PubMed1979

Self-awareness and transgression in children: two field studies.

Two field studies explored the relationship between self-awareness and transgressive behavior. In the first study, 363 Halloween trick-or-treaters were instructed to only take one candy. Self-awareness induced by the presence of a mirror placed behind the candy bowl decreased transgression rates for children who had been individuated by asking them their name and address, but did not affect the behavior of children left anonymous. Self-awareness influenced older but not younger children. Naturally occurring standards instituted by the behavior of the first child to approach the candy bowl in each group were shown to interact with the experimenter's verbally stated standard. The behavior of 349 subjects in the second study replicated the findings in the first study. Additionally, when no standard was stated by the experimenter, children took more candy when not self-aware than when self-aware.

Awareness↗
PubMed1979

Carboxymethyl cellulose, a nonimmunogenic hapten carrier with tolerogenic properties.

This communication reports on the tolerogenic properties of carboxymethyl cellulose (CMC) as a nonimmunogenic carrier for 2.4 dinitrophenyl (DNP) and the benzylpenicilloyl determinant (BPO). Either normal or primed mice, given an optimal dose of 250 micrograms per animal of DNP CMC, when challenged with an immunogenic form of the hapten as early as 30 min or as late as 21 days thereafter were completely and specifically unresponsive to it. Experimental evidence suggests that this unresponsiveness is not due to suppressor cells. Furthermore, DNP CMC induces tolerance in vivo but fails to do so in vitro under conditions at which other tolerogenic carbohydrate hapten conjugates such as DNP-dextran do. This together with comparative studies of tolerance induction kinetics by DNP CMC and DNP-dextran in vivo led us to conclude that molecular properties other than the epitope density must be attributed to CMC's tolerogenic potential. CMC may also be used as a tolerogenic carrier for BPO with respect to IgE antibody production. Thus, normal or primed mice injected with the BPO CMC conjugate were found specifically unresponsive to a challenge with an immunogenic form of penicillin.

Animals↗
PubMed1978

Treatment of lupus nephritis in adult (NZB + NZW)F1 mice by cortisone-facilitated tolerance to nucleic acid antigens.

Adult female (NZB + NZW)F1 mice were treated with cortisone, cortisone with tolerogen (isologous NZB IgG-nucleosides conjugates) or cortisone with isologous IgG free of nucleosides. Other treatments also included tolerogen or isologous IgG alone, and cortisone together with denatured DNA. All untreated mice died by 10 mo of age. Cortisone prolonged the survival rate. This effect was further improved by combined treatment of cortisone and tolerogen. Prolonged survival was accompanied by a decrease in proteinuria. Other treatments failed to influence either survival or proteinuria. Although cortisone did not prevent the appearance of antibody to denatured DNA, cortisone and tolerogen suppressed them in most of the animals. Preexisting antibody to denatured DNA was reduced by cortisone and cortisone and tolerogen, but not by cortisone and IgG. In contrast, antibody to native DNA bore no relationship to therapy. Animals living beyond 1 yr of age, regardless of the treatment, fall into three histopathological categories: (a) severe nephritis, as in untreated animals, (b) moderate nephritis (with absence of severe alteration of the glomerular basement membrane, i.e. the histological counterpart of prolonged survival), (c) minimal nephritis. In a small number of animals treated with cortisone or cortisone and IgG and in 6/20 animals treated with cortisone and tolerogen, minimal lesions as judged by light, fluorescent, and electron microscopy were found. These last mice were in good health at 15-16 mo of age, twice the life-span of untreated mice. In conclusion, these data suggest that tolerance to nucleic acid antigens facilitated by cortisone offers a promising new approach to treat established murine lupus nephritis.

Animals↗
PubMed1976

Antigen recognition. IV. Discrimination by antigen-binding immunocompetent B cells between immunity and tolerance is determined by adherent cells.

Mouse spleen cells capable of specifically binding intrinsically tritium-labeled polymerized flagellin (POL) (labeling by biosynthesis of flagellar protein) via IgM receptors were found to comprise a distinct population of about 20-50 cells per 10(6) lymphocytes. Evidence is presented that the majority of mouse spleen cells binding tritium-labeled POL undergoes blastogenesis after antigen capping, antigen shedding, and receptor reformation. Under conditions of tolerance induction in vitro, however, loss of antigen from the cell surface was inhibited. Such inhibition of antigen redistribution and shedding was reversed by a short pulse of colchicine and new antigen receptors were formed. In spite of this, colchicine had no effect on the tolerant state. However, tolerance could be broken, regardless of presence or absence of the alkaloid, with radioresistant theta-negative accessory (A) cells (adherent cells) from normal but not from tolerant spleen cell populations. "Tolerant" A cells, although they were incapable of cooperating in a response to POL, were capable of participating in a response to a second unrelated antigen. It is concluded that tolerance to POL in vitro is induced by mechanisms other than the physical blocking of bone marrow-derived (B) cell receptors by antigen. Most likely, the discrimination by the B cell between a tolerogenic and immunogenic signal is mediated by A cells.

Animals↗
PubMed1976

Requirement for accessory cells in the antibody response to T cell-independent antigens in vitro.

The antibody responses of mouse spleen cells in vitro to three thymus-independent (TI) antigens namely, polymeric flagellin (POL) of Salmonella adelaide, DNP-Ficoll and "soluble" sheep erythrocyte (SRBC) antigen, were found to be dependent on adherent accessory cells (A cells) but to a lesser degree than the response to intact SRBC. Evidence for this comes from selective depletion of A cells from spleen cells and reconstitution with A cell-rich populations. Thus, depletion of A cells by adherence on glass resulted in abolition of the response to SRBC leaving the response to POL intact. More thorough removal of A cells by treatment with carbonyl iron powder was required for appreciable reduction of the responses to POL, DNP-Ficoll and "soluble" SRBC. This reduction in responsiveness was not due to poor cell survival after A cell depletion or to the loss of immunocompetent cells since 1) the recoveries of viable cells in all cultures were similar; 2) the contents of theta- and Ig-bearing cells and tritium-labeled POL-binding cells were unaltered after carbonyl iron treatment, and 3) responsiveness was fully restored by the addition of irradiated and anti-theta-treated A cells from the peritoneal cavity or the spleen. Hence, the hitherto A cell independence of TI antigens on which some theories of B cell activation are based is a result of inadequate depletion procedures, and the minimal model for B cell activation must take into account two cell types: B cells and A cells.

Animals↗
PubMed1976

Effects of prior destructive behavior, anonymity, and group presence on deindividuation and aggression.

Three of Zimbardo's deindividuation input variables (group presence, anonymity, and arousal) were manipulated in laboratory experiment, and their effects on aggression and deindividuation were measured. Only arousal produced a significant increase in aggression (p less than .05), while group presence produced a significant decrease in aggression (p less than .01). Anonymity had no significant effect on subjects' aggressiveness. Deindividuation per se was measured on a postsession questionnaire that assessed subjects' memory for their own aggressive behavior, self-consciousness, concern for social evaluation, and memory for central and peripheral cues. Only arousal condition participants showed deindividuation changes, but a factor analysis revealed that the deindividuation changes did not comprise a unified factor. Also it did not appear that the internal changes caused aggressive behavior, since the correlation between the two was low.

Aggression↗
PubMed1976

Effect of lipopolysaccharide on the induction of tolerance to polymerized flagellin.

The effect of bacterial lipopolysaccharide (LPS) on the induction of tolerance to the T-independent polymerized flagellar protein (POL) of Salmonella adelaide strain SW1338 was studied in vitro. In contrast to published results with T-dependent antigens, LPS failed to prevent or reverse tolerance induction to POL under conditions in which tolerance was reversible by other means. Moreover, the addition of high doses of LPS to slightly supra-immunogenic concentrations of POL augmented-tolerance induction. These results suggest that the mitogenic properties of LPS are insufficient to convert a tolerogenic dose of POL into an immunogenic one and, therefore, that LPS may act only on T-dependent B cell responses. Since both POL (1338) and LPS are T-independent, mitogenic and so-called "polyclonal B cell activators," these data have implications for signal discrimination in the immune response.

Animals↗
PubMed1975

Personality research: components of variance attributable to the person and the situation.

Studies involving personality and situational variables were surveyed. Studies permitting determination of main effects and interactions involving these variables have increased since 1950. In one comparison, situational main effects were significant in 65.5% of the cases, whereas the figure was 31% for individual difference variables and 59.9% for interactions. In another comparison, 35% of situational main effects accounted for more than 10% of the variance, compared with 29% for personality indexes; 19% of the situational variable effects accounted for more than 20% of the variance, compared with 14% of the personality main effects. Low percentages of variance were accounted for by all variables investigated: situational, personality, demographic, and interactions among these variables.

Academic Dissertations as Topic↗
PubMed1975

Effects of altered responsibility, congnitive set, and modeling on physical aggression and deindividuation.

This laboratory investigation using 64 college students as subjects assessed the role of three disinhibiting variables in producing both physical aggression and an internal state of deindividuation. Altered responsibility, congnitive set, and modeling were manipulated in a factorial design, and all three variables significantly increased physical aggression. No interaction produced significant results. The increase due to altered responsibility and varying cognitions supports Zimbardo's theory of deindividuation which relates certain input variables to wild, impulsive behavior. Questionnaire data indicated that the increase in aggression was not accompanied by internal mediational factors such as reduced self-awareness. It appears that disinhibiting forces may produce increases in antisocial behavior without necessarily producing a deindividuated internal state.

Aggression↗