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J Bienenstock

Publications and source records attributed to J Bienenstock.

At least 19 recordsLinked to original sources
PubMed1995

Naloxone exacerbates intestinal and systemic anaphylaxis in the rat.

Following sensitization to ovalbumin (OA), male Wistar rats were pretreated with naloxone (20 mg/kg i.p.) and subjected to antigen challenge (3 mg OA i.p.). Naloxone exacerbated both systemic and intestinal anaphylaxis when injected 10 and 90 min before the antigen challenge. This was evidenced by a more pronounced drop in rectal temperature, higher hematocrit values, and by an enhanced elevation of basal short-circuit current (an indication of the secretory tone of the small intestine studied in Ussing chambers). Pretreatment with an equipotent does of methylnaloxone (200 mg/kg i.p.), a peripherally acting opiate antagonist, exacerbated the indices of intestinal anaphylaxis but had no apparent effect on indices of systemic anaphylaxis. Thus, our data strongly suggest that in the rat, components of the systemic hypersensitivity reaction are mediated through central opioid receptors, whereas the changes in gut function characterizing intestinal anaphylaxis are mediated through peripheral opioid receptors.

Anaphylaxis↗
PubMed1994

Lymphoid tissues induce NGF-dependent and NGF-independent neurite outgrowth from rat superior cervical ganglia explants in culture.

Induction of neurite outgrowth from superior cervical ganglia (SCG) by rat lymphoid tissues was studied using a tissue culture model. Neonatal rat SCG were cultured with 6-12-week-old rat thymus, spleen, or mesenteric lymph node (MLN) explants in a Matrigel layer, in defined culture medium without exogenous nerve growth factor (NGF). SCG were also co-cultured with neonatal rat heart (as positive control) or spinal cord (SC; as negative control). To determine whether inflammation affects the ability of lymphoid tissues to induce neurite outgrowth, we also examined MLN at various times after infecting rats with Nip-postrongylus brasiliensis (Nb-MLN). In one series of experiments, a single lymphoid tissue explant was surrounded by four SCG at a distance of 1 mm. The extent of neurite outgrowth was determined by counting the number of neurites 0.5 mm away from each ganglion at several time points. Adult thymus and, to a lesser extent, spleen had strong stimulatory effects on neurite outgrowth from SCG after 12 hr or more in culture. For thymus tissue, this was similar to the positive control heart explants. MLN from normal rats had minimal effect on neurite outgrowth; however, Nb-MLN showed a time-dependent enhancement of the neurite outgrowth, maximal at 3 weeks after infection. The relative efficacy of neurite outgrowth induction (heart > or = thymus > or = Nb-MLN > or spleen > or = MLN > or = SC) was confirmed in a second series of experiments where one SCG was surrounded by three different tissue explants. We then examined the role of 2.5S NGF, a well-known trophic factor for sympathetic nerves, in the lymphoid tissue-induced neurite outgrowth. Anti-NGF treatment of co-cultures of SCG and heart almost completely blocked the neurite outgrowth. Anti-NGF also significantly inhibited thymus- and spleen-induced neurite outgrowth, but not as effectively as heart-induced neuritogenesis (93, 80, and 77% inhibition at 24 hr; 86, 70, and 68% inhibition at 48 hr for heart, thymus, and spleen, respectively). On the other hand, anti-NGF inhibited only 8% of neurite outgrowth induced by 3-week post-infection Nb-MLN at 24 hr, and 41% at 48 hr. These data show that several adult rat lymphoid tissues exert neurotrophic/tropic effects. The predominant growth factor in thymus and spleen is NGF, while Nb-MLN produces factor(s) which is (are) immunologically distinguishable from NGF.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1994

Strain-related difference in susceptibility to anaphylactic shock correlates with measures of spontaneous activity.

The onset and severity of anaphylactic reactions in the rat have so far been related to Pavlovian conditioning, previous exposure to stress, and pretreatment with opioid agonists and antagonists. In this study, we compared two strains of rats derived from the same genetic pool (one outbred, Wistar, and one inbred, Wistar-Kyoto) for their susceptibility to anaphylactic shock (AS). In Experiment 1, baseline differences in the overt behavior of the two strains were established. In Experiment 2, following sensitization to ovalbumin, rats of both strains were challenged with antigen by either the intraperitoneal or the intragastric route. Wistar-Kyoto rats were more susceptible to the induction of AS as evidenced by a more pronounced drop in rectal temperature and greater intensity of clinical signs, although there was no evidence for strain-related differences in IgE titres. Experiment 3 replicated and extended the findings of Experiment 2. Again, Wistar-Kyoto rats were found to be more susceptible to the induction of AS. In addition to a greater drop in rectal temperature and intensity of clinical signs, more pronounced changes in gut function were found in the Wistar-Kyoto strain. This was indicated by an elevation of basal short-circuit current (an indication of the transport tone of the tissue mounted in the Ussing chambers). Most importantly, there was a strong linear relationship between measures of overt behaviour and various physiological indices of AS. This finding indicates that the same genetic basis may be responsible for the observed strain-related differences in behavior and susceptibility to AS, and that variations in nonimmunological factors of mast cell activation may also contribute to the observed differences in the susceptibility to anaphylactic reactions.

Anaphylaxis↗
PubMed1994

Morphological and functional characteristics of peritoneal mast cells from young rats.

To study why neonatal and young rats are resistant to the effects of some secretagogues, such as compound 48/80 and 2.5-S nerve growth factor, we examined peritoneal mast cells from 14-15-day-old rats (young rats) and compared them to peritoneal mast cells from adults. Peritoneal mast cells from young rats contain approximately one-tenth of the amount of histamine observed in adult peritoneal mast cells. However, both cell populations contained similar low levels of the mucosal mast cell-associated protease rat mast cell protease II. Histochemical analysis of peritoneal mast cells from young rats using safranin O and berberine sulphate suggested that only a portion of the granules of these cells contained heparin. At an ultrastructural level the young rat peritoneal mast cell contains relatively few granules. The majority of mast cells from young rats have a bilobed or indented nucleus which is only rarely observed in adult cells. Functionally, the young rat peritoneal mast cell demonstrates a significantly reduced histamine release in response to the connective tissue mast cell-specific secretagogues compound 48/80 and 2.5-S nerve growth factor. In contrast, the percent histamine release in response to the neurotransmitter substance P, which degranulates both connective tissue mast cells and intestinal mucosal mast cells, was similar in the adult cells and the young rat cells. This study demonstrates substantial differences between the young rat and adult peritoneal mast cells which may explain the ability of very young animals to withstand large doses of certain secretagogues.

Animals↗
PubMed1994

The interaction between mast cells and nerves in the gastrointestinal tract.

Study of the neuroimmune system typifies the new integrative approach to biological systems. Numerous spatial associations between mast cells and nerves have been described, and data are accumulating on the functional aspects of this relationship. Here, Derek McKay and John Bienenstock review the bidirectional communication between mast cells and nerves as a homeostatic unit in the regulation of gut physiology and host defense.

Animals↗
PubMed1994

The role of mast cells in inflammatory reactions of the airways, skin and intestine.

The concept that mast cells play a key role in the initiation of acute allergic responses has been around for many years. However, the role of mast cells in the chronic processes that are the hallmark of inflammatory disease is still poorly understood. With better techniques to study mast cell function it has become clear that these cells may have a much wider role in immune responses and regulation than previously recognized. Exciting progress has been made over the past year in defining the breadth of mast cell functions in inflammation. Further studies are necessary to evaluate the in vivo significance of many of these findings.

Animals↗
PubMed1994

Phenotypic and functional assessment of intraepithelial lymphocytes bearing a 'forbidden' alpha beta TCR.

Differences in the surface antigen phenotype, such as the expression CD8 as an alpha alpha homodimer or the lack of Thy-1, on intestinal intraepithelial lymphocytes (IEL) are related, in part, to alternative differentiation pathways. The relationship of IEL lacking the pan-T cell marker CD5 to these IEL, their TCR repertoire and function has not been examined directly. We explored the TCR repertoire and function of the CD5- IEL subset in relation to the expression of the 'autospecific' V beta 6 TCR in MIs-1a mice and to gamma delta TCR. The results indicate that CD5 expression was absent on the majority of TCR gamma delta IEL (96.9%) and on a significant proportion of TCR alpha beta IEL (25.0%). Virtually all IEL in DBA/2 (MIs-1a) mice that expressed the 'autospecific' V beta 6 TCR were CD5-, and this correlated with the expression of CD8 alpha alpha. To assess the functional capacity of this subset of IEL, we examined proliferation and IL-2 production in response to TCR activation. Although CD5- IEL proliferated in response to anti-CD3, IEL bearing TCR V beta 6, in MIs-1a mice, were not responsive to TCR-mediated activation. Similarly, TCR gamma delta IEL were not responsive to stimulation by anti-TCR gamma delta antibodies. The addition of exogenous IL-2, however, reconstituted the proliferative response of both TCR gamma delta IEL and the TCR V beta 6 expressing IEL. We conclude that the lack of CD5 defines a unique subset of intraepithelial T cells expressing either TCR gamma delta or alpha beta that include potentially autoreactive cells that remain anergic in the absence of IL-2.

Animals↗
PubMed1994

Picomolar doses of substance P trigger electrical responses in mast cells without degranulation.

The nervous and immune systems may communicate through the action of neurotransmitters on mast cells. We used patchclamp electrophysiology to assess the responses of rat peritoneal mast cells (PMC) to low levels of substance P (SP), which are likely to occur in situ. SP at 50 nM, or even 10,000 times reduced to 5 pM, triggered an outwardly rectified Cl- current (50 nM: 10 of 10 cells; 5 pM: 10 of 11 cells), although degranulation never occurred. Electrical responses were delayed (mean 102.6 s for 5 pM SP), appearing as brief current pulses. Reapplication of SP resulted in peak current augmentation (mean 15.3 pA before exposure to SP, 47.3 pA after 1st exposure, and 116.0 pA after 2nd exposure to 5 pM SP). Cells repetitively exposed to SP degranulated 5-15 min and > 25 min after the second exposure to 50 nM SP (10 of 10 cells) or 5 pM SP (5 of 9 cells), respectively. This effect was reduced by 10 microM 5-nitro-2-(3-phenylpropylamino)benzoic acid or when extracellular Ca2+ was removed, indicating a dependence on Cl- conductance and extracellular Ca2+. We propose that whole cell current oscillations in the absence of degranulation are the functional correlate of priming, a process that increases cellular responsiveness for the subsequent stimulation.

Animals↗
PubMed1994

Pertussis toxin stimulates hypersensitivity and enhances nerve-mediated antigen uptake in rat intestine.

We previously reported that intestine from rats sensitized to ovalbumin (Ova), using Bordetella pertussis vaccine as adjuvant, demonstrated a rapid secretory response [increase in short-circuit current (Isc)] to Ova upon secondary challenge. Here, we examined the role of pertussis toxin, the active component of the vaccine, in the response. Sensitization of Sprague-Dawley rats by intraperitoneal injection of recombinant wild-type pertussis toxin (wPT) plus Ova enhanced intestinal responses (at day 14: approximately 20-fold for luminal antigen, approximately 2.5-fold for serosal antigen) compared with rats sensitized by injection of Ova alone. In contrast, sensitization with an enzymatically inactive mutant pertussis toxin (mPT, different in two amino acids) produced no significant effect. Ova-specific immunoglobulin (Ig) E and IgG2a antibodies and greater numbers of mucosal mast cells were documented in wPT-sensitized rats. In addition, the Isc response to electrical transmural stimulation of nerves in intestinal preparations was significantly augmented. Neurotoxin inhibited the secretory response to luminal but not serosal antigen. Immunophysiological stimulation by wPT was still evident 8 mo postsensitization. Our studies indicate that pertussis toxin causes long-lasting hypersensitivity to coadministered antigens, involving increased production of reaginic antibodies, hyperplasia of mucosal mast cells, and enhanced neurally mediated uptake of antigen across the intestinal epithelium. These findings suggest a potential role for bacterial products in the development of immunophysiological reactions to ingested antigens.

Animals↗
PubMed1994

Hormones and local immunity.

The modulatory role of hormones in the regulation of the immune response has been well documented. Here, we present some thoughts on how sex hormones affect immunity, particularly at mucosal sites. We further discuss the possible pitfalls and difficulties associated with analysis of the data.

Animals↗
PubMed1992

Substance P induces whole cell current transients in RBL-2H3 cells.

To investigate the basis of interactions between nerves and mast cells, we tested the actions of the neuropeptide substance P (SP) on whole cell current characteristics of RBL-2H3 cells (homologous to mucosal mast cells). Control RBL cells showed a K(+)-dependent inwardly rectified current. SP (10(-6) M) caused transient, frequently repetitive increases in current amplitude, which at a membrane potential (Vm) of -80 mV rose by -1,020.0 +/- 223.4 pA after SP application compared with -6.8 +/- 1.7 pA for control. This response was characterized by a lag phase of 102 +/- 16 s. Seventeen percent of cells showed spontaneous transients in the current amplitude from the beginning of the recording. After SP administration, the amplitude of these transients increased by 6.3 +/- 2.0-fold. Responses to SP were mimicked by the application of ionomycin. For both SP and ionomycin, there was a dose dependency of the lag phase. Removal of extracellular calcium abolished the response for 10(-6) M SP but not for 6.6 x 10(-6) M ionomycin. During current transients, the whole cell current had both inward and outward rectified components with the zero current Vm shifted from -87.3 +/- 3.2 mV at control to -10.8 +/- 1.7 mV. We compare the SP-evoked current responses in mucosal-type mast cells with those described in connective tissue type.

Animals↗
PubMed1992

Sympathetic nerve contact alters membrane resistance of cells of the RBL-2H3 mucosal mast cell line.

Indirect evidence links sensory nerves with mast cells (MC) in inflammatory reactions of airway, skin, and intestine. Isolated MC secrete histamine, serotonin, and other inflammatory mediators in response to neuropeptides such as substance P (SP) in vitro. To obtain direct evidence of nerve/MC interactions, we used a tissue culture model involving the co-culture of murine sympathetic neurons and rat basophilic leukemia (RBL) cells (homologous to mucosal MC). An electrophysiologic analysis of the consequences of neuron/RBL cell contacts showed that neurite contact with RBL cells reduced the control input resistance (Ro) of 61.8 +/- 3.2 (n = 110) M omega to 22.4 +/- 4.8 (n = 13) M omega (P less than 0.01) without change in the membrane potential. Time course studies showed that Ro of RBL cells with neurite contact was always lower by 30 to 54% than adjacent RBL cells lacking such contact. This effect was not seen in RBL cells cultured on rat fibroblasts. Direct application of SP, bradykinin, and somatostatin, but not acetylcholine, noradrenaline, or the putative neurotransmitter ATP, could partly mimic the effect of neurite contact. Therefore, neurotransmitter release from sympathetic neurons in contact with RBL cells may decrease RBL cell membrane resistance, possibly leading to activation.

Animals↗
PubMed1992

Expression of nerve growth factor receptor immunoreactivity on follicular dendritic cells from human mucosa associated lymphoid tissues.

Nerve growth factor (NGF) was originally considered as a trophic factor for peripheral sympathetic and sensory neurones; however, recent reports indicate that NGF may induce proliferation of immune and haematopoietic cells. Histochemical studies conducted in human spleen and lymph nodes have suggested the presence of NGF receptor (NGF-R) immunoreactive elements in secondary follicles; however the nature of the cells bearing the NGF-R in lymphoid tissue has not been determined. In this paper we report the results of an immunohistochemical study conducted on mucosa associated lymphoid tissue. Using a specific monoclonal antibody to human NGF-R (mAb 20.4) we observed an NGF-R-immunoreactive population in all secondary lymphoid follicles examined. Double immunostaining revealed that this population was composed of follicular dendritic cells (FDC); lymphoid cells within the germinal centres did not appear to be 20.4 immunoreactive. Cell suspensions from tonsillar follicles also contained NGF-R immunopositive dendritic cells which were enriched by a 20.4 labelled magnetic bead procedure, revealing cells with the morphological characteristics of FDC. Mononuclear cells from human peripheral blood did not contain any NGF-R-immunoreactive elements using our techniques.

Adolescent↗
PubMed1991

Synergistic effects of nerve growth factor and granulocyte-macrophage colony-stimulating factor on human basophilic cell differentiation.

We have recently shown that nerve growth factor (NGF) promotes human granulopoiesis, specifically augmenting basophilic cell differentiation observed in methylcellulose hematopoietic colony assays of human peripheral blood. Because the NGF effect was seen in the presence of conditioned medium derived from a human T-cell line (Mo-CM) containing granulocyte-macrophage colony-stimulating factor (GM-CSF), we examined interactions of purified NGF and recombinant human GM-CSF (rhGM-CSF) on granulocyte growth and differentiation. rhGM-CSF stimulated a dose-dependent increase in methylcellulose colony growth at concentrations between 0.1 U/mL and 10 U/mL, and in the presence of NGF at 500 ng/mL this effect was enhanced. The number of basophilic cell colony-forming units (CFU-Baso) and histamine-positive colonies increased synergistically when NGF was added to rhGM-CSF. Furthermore, because Mo-CM acts with sodium butyrate to promote basophilic differentiation of alkaline-passaged myeloid leukemia cells, HL-60, we also examined the interaction of NGF and Mo-CM or rhGM-CSF using this assay. In the presence of NGF, Mo-CM at concentrations of 0.5% to 20% vol/vol, and rhGM-CSF at concentrations of 0.1 U/mL to 100 U/mL synergistically increased histamine production by butyrate-induced, alkaline-passaged HL-60 cells; this was associated with the appearance of metachromatic, tryptase-negative, IgE receptor-positive cells. The effects of rhGM-CSF or Mo-CM were completely abrogated by a specific anti-rhGM-CSF neutralizing antibody in methylcellulose, with or without NGF; the NGF synergy with rhGM-CSF in the HL-60 assay was also inhibited by either anti-rhGM-CSF or anti-NGF antibody. These studies support the notion that differentiation in the basophilic lineage may be enhanced by NGF acting to increase the number of GM-CSF-responsive basophilic cell progenitors.

Basophils↗
PubMed1991

Formation of contacts between mast cells and sympathetic neurons in vitro.

Functional interactions between mast cells and peripheral nerves may occur at sites of association seen in vivo. To study the interactions, we developed a tissue culture model of murine sympathetic neurons co-cultured with rat basophilic leukaemia (RBL-2H3) cells (homologues of mucosal mast cells) or rat peritoneal mast cells. In co-cultures of up to 3 days, light microscopy identified neurite contacts with peritoneal mast cells or RBL-2H3 cells, but not with glial cells or fibroblasts. Electron microscopy confirmed membrane-membrane contact between neurites and RBL-2H3 cells. Time-lapse analysis of interactions between neurons and RBL-2H3 cells showed that 60-100% of the cells in a given field acquired neurite contact within 17 h. In matching control studies, there was no increase in the frequency of neurite contact with cells of the rat plasmacytoma line (YB2/0): these were not selected as targets, and contacts were broken if formed. Time-lapse records of the derivation of neurites from their path suggested a neurotropic effect of mast cells, with neurite contact ensuing when the intervening distance was less than 36 +/- 4 microns. Once formed, contacts were invariably maintained throughout the period of examination (up to 72 h), in contrast to YB2/O or fibroblast contacts. We conclude that neurons selectively form and maintain connections with cells representative of rat connective tissue-type and mucosal mast cells in vitro. Similar interactions in vivo could promote nerve/mast cell contacts, which may allow bidirectional communication between the nervous and immune systems.

Animals↗