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H R Miller

Publications and source records attributed to H R Miller.

At least 127 records · Page 7Linked to original sources
PubMed1986

Mast cell subsets in the rat distinguished immunohistochemically by their content of serine proteinases.

The specificities of antibodies raised in rabbits against rat mast cell proteinase 1 (RMCP 1) from connective tissue mast cells (CTMC), and against RMCP II from mucosal mast cells (MMC), were analysed by SDS-PAGE and Western blotting. Significant cross-reactivity was detected, and was eliminated by affinity purification and cross-absorption techniques. The resultant F(ab')2 antibodies, monospecific for each enzyme, were used for the immunohistochemical localization of RMCP I and II in rat tissues. Cells in skin, tongue, intestinal serosa and lung parenchyma which, by histochemical techniques, have been identified as CTMC, contained RMCP I exclusively. Cells in jejunal lamina propria and bronchial epithelium, previously classified as MMC, contained RMCP II. The results demonstrate the feasibility of distinguishing mast cell subsets by their content of serine proteinases.

Animals↗
PubMed1985

The Harris-Lingoes subscales: fact or fiction?

The subjectivity of the Harris-Lingoes MMPI content subscales was examined by asking expert judges (N = 13) to group items from appropriate clinical scales that represented similar content, attitudes or traits. The mean subgroups were compared to the Harris-Lingoes subscales, and item groupings were consensually validated and replicated. Judges developed more content categories per scale than Harris and Lingoes, but showed relatively little agreement on item groupings. Nine consensually validated and replicated subscales were highly similar to nine Harris-Lingoes subscales, while nine other replicated subscales were moderately similar to seven Harris-Lingoes subscales. Twelve Harris-Lingoes subscales were unrelated to the replicated subscales.

Humans↗
PubMed1985

Neuron-specific growth cone properties as seen in identified neurons of Helisoma.

By using cell-cultured identified neurons of the snail Helisoma, we demonstrate that the growth cones of different neurons are intrinsically different from one another in terms of their structure, behavior, and response to environmental signals. Structurally neuron 5 has a greater number of filopodia per growth cone, has shorter filopodia, and has a smaller interfilopodial distance than neuron 19. Behaviorally, the growth cones of neuron 5 advance over the substratum at a faster rate than those of neuron 19; and the growth cones of neuron 19, but not of neuron 5, respond to the presence of serotonin in their environment by retracting their filopodia. In addition to such intrinsic differences between the growth cones of different neurons, we also demonstrate that the separate growth cones of a single neuron, while having identical properties, can act independently of one another. Focal application of serotonin to a growth cone causes only a localized retraction of that growth cones' filopodia. Other growth cones that are attached to the same neuron but that are not exposed to serotonin retain their normal structural features.

Animals↗
PubMed1985

Depletion of mucosal mast cell protease by corticosteroids: effect on intestinal anaphylaxis in the rat.

Rats primed by infection with the intestinal nematode Nippostrongylus brasiliensis and challenged intravenously with soluble whole-worm antigen undergo systemic anaphylactic shock. The primary lesions are in the gut and include increased permeability of the mucosa together with release, into enteric secretions, of a mucosal mast cell (MMC)-specific serine proteinase, rat mast cell protease II (RMCP-II). This enzyme is also released into the blood of shocked rats. These manifestations of anaphylaxis were abolished in rats previously treated with corticosteroids (methylprednisolone acetate, 25 mg per kg of body weight, 48 and 24 hr before i.v. challenge with antigen). Suppression of the response was associated with depletion of RMCP-II and of MMC from the intestinal mucosa. Depletion occurred 4-24 hr after treatment with as little as 1 mg of methylprednisolone per kg. By contrast, neither connective tissue mast cells nor serum levels of parasite-specific IgE were depleted in rats given 2 X 25 mg of methylprednisolone per kg. The capacity of unprimed treated rats to mount passive cutaneous anaphylaxis was, however, impaired.

Anaphylaxis↗
PubMed1985

Systemic release of mucosal mast cell protease during infection with the intestinal protozoal parasite, Eimeria nieschulzi. Studies in normal and nude rats.

The systemic secretion of rat mucosal mast cell protease (RMCPII), a major product of rat mucosal mast cells (MMC), was examined during primary infections with the protozoan parasite, Eimeria nieschulzi in CFH/B, athymic (rnu/rnu) and euthymic (rnu/+) rats. Release of RMCPII into the blood stream (2.9 micrograms/ml of serum) of normal rats occurred within 1 day after infection. This response developed 3-6 hours after inoculation with oocysts, was dose-dependent, and was found in both naive and immune rats. Maximal release of RMCPII (4.5 micrograms/ml of serum) in naive rats occurs 9 days after primary infection, whereas the numbers of MMC and concentrations of mucosal RMCPII were maximal 14 days after infection, by which time the systemic RMCPII response had begun to decline. The numbers of MMC and concentrations of mucosal RMCPII in uninfected nude rats were similar to those in the heterozygous (rnu/+) litter-mates. After infection, the numbers of MMC and concentrations of mucosal RMCPII increased in the heterozygotes but not in nude rats. Similarly, RMCPII was detected systemically only in the heterozygotes.

Animals↗
PubMed1985

Histochemical demonstration of chymotrypsin like serine esterases in mucosal mast cells in four species including man.

Serine esterases were detected in the granules of mucosal mast cells from rat, mouse, sheep, and man. Successful demonstration of enzyme activity required brief fixation (6 h) of tissues in 4% paraformaldehyde. Staining with naphthol AS-D chloroacetate produced an intense red reaction product in intraepithelial mucosal mast cells (globule leucocytes) and mucosal mast cells within the lamina propria of the gastrointestinal tract. The mast cell identity of cells stained for esterase was confirmed by sequential staining with toluidine blue (pH 0.5). Furthermore, the numbers of cells detected after staining for esterases or with toluidine blue were highly correlated. Esterase activity within mucosal mast cells/globule leucocytes from all species was inhibited with the serine enzyme inhibitor phenylmethylsulphonyl fluoride. Further histochemical studies with the substrate, N-acetyl-DL-phenylalanine B-naphthyl ester, indicated that mucosal mast cells and globule leucocytes contain esterases which are chymotrypsin like in substrate specificity.

Animals↗
PubMed1985

The presence in blood of both glycosaminoglycan and mucosal mast cell protease following systemic anaphylaxis in the rat.

The appearance in blood of rat mast cell protease II (RMCPII) and glycosaminoglycan (GAG) was examined in normal and Nippostrongylus brasiliensis-primed rats challenged intravenously with worm antigen. Systemic release of these two products occurred only in immune recipients of antigen; substantial levels of RMCPII were also present in the intestinal perfusates of these same rats and there was depletion of both RMCPII and mucosal mast cells (MMC) from the intestinal mucosa. Depletion of MMC was evident after staining for proteoglycan or for serine esterase and the mast cell counts with both histochemical techniques were highly correlated. Taken together, the results suggest that MMC are likely to be the principal source of secreted GAG and RMCPII.

Anaphylaxis↗
PubMed1985

Intestinal mucosal mast cells: isolation from rat lamina propria and purification using unit gravity velocity sedimentation.

Mucosal mast cell (MMC) suspensions obtained from the rat intestinal lamina propria by collagenase digestion (35.2 +/- 3.2% MMC) were enriched to 65.5 +/- 5.2% MMC by the use of a discontinuous gradient (30%/80%) of Percoll. Further purification to 95.7 +/- 1.3% MMC was achieved using velocity sedimentation at unit gravity (Sta-Put). Analysis of the cells throughout the purification procedure confirms that the purified MMC are representative of the MMC in the initial isolated cell suspension. No differences were seen in terms of size, histamine content, protease content and responsiveness to secretagogues among the initial isolated population, the Percoll-enriched population and the Sta-Put-purified population. This study represents a major advance in mast cell research in that, for the first time, mast cells isolated from a homogeneous in vivo mucosal source have been obtained at levels of purity sufficient for specific biochemical characterization. Such characterization will aid in the interpretation of the role of MMC in disease and will provide a firm basis of knowledge of the form and function of intestinal MMC for comparison with mast cells derived from other mucosal sites or cultured in vitro from various organs.

Animals↗
PubMed1984

Concomitant detection of mucosal mast cells and eosinophils in the intestines of normal and Nippostrongylus-immune rats. A re-evaluation of histochemical and immunocytochemical techniques.

The granules of mucosal mast cells (MMC) in the rat and man are apparently poorly fixed with formaldehyde and special fixation techniques are normally used to demonstrate MMC glycosaminoglycans (GAG) in these two species. However such techniques do not permit the study of MMC granule enzyme cytochemistry or the demonstration of eosinophils. We have, therefore, examined some histochemical and immunocytochemical properties of MMC and eosinophils in normal and parasitised rats following various fixation procedures. Immersion fixation of rat intestine in 4% paraformaldehyde for 6 h not only facilitated the demonstration of MMC glycosaminoglycans with basic dyes but also permitted the concomitant staining of eosinophils with acidophilic dyes. A MMC granule-associated serine esterase was also demonstrated by enzyme cytochemistry and rat mast cell protease II was detected within MMC granules by immunocytochemistry. This new methodology obviates the requirement for separate fixation procedures in the identification and characterisation of MMC/eosinophil interactions in normal and parasitised rat intestinal mucosa.

Animals↗
PubMed1984

Manifestations of resistance to ovine ostertagiasis associated with immunological responses in the gastric lymph.

Groups of previously infected and worm-free sheep were serially killed up to 10 days after challenge with 50 000 Ostertagia circumcincta larvae. Two similar groups of sheep were killed 10 days after challenge with 1000 larvae. The previously infected sheep were resistant to the smaller challenge dose in that fewer, stunted worms were recovered from them than from controls. However, this resistance was not as marked as that observed in the previously infected sheep which received the large challenge, because proportionally fewer worms were recovered after the 50000 dose and the great majority of these were arrested at the early fourth stage. The gastric lymph ducts of 6 previously infected sheep were cannulated successfully and a marked local immune response was detected in 3 sheep which were challenged with 50 000 larvae. No response was detected in 3 cannulated sheep challenged with 1000 larvae. In the lymph of the 50 000 dose group, a temporary increase in pepsinogen activity suggested that a hypersensitivity reaction related to the presence of large numbers of mucosal mast cells began between 24 and 48 h after challenge. This was followed by marked increases in the cellular and IgA content of lymph, which reached peaks on days 3 and 6, respectively. It is suggested that the response detected in the gastric lymph reflected aspects of a local immune reaction in the abomasal mucosa and that this reaction accounted for the enhanced degree of resistance to the larger challenge dose.

Animals↗
PubMed1984

The isolation and characterization of globule leucocytes: their derivation from mucosal mast cells in parasitized sheep.

Ovine mucosal mast cells and globule leucocytes have been isolated from the abomasum of normal sheep, and from animals challenged with Ostertagia circumcincta. The ultrastructural, morphological and histochemical properties of these cells have been investigated. The granules of ovine mucosal immunoglobulin and a serine esterase. These cells also possess surface immunoglobulin. Cells morphologically intermediate between mucosal mast cells and bulin. Cells morphologically intermediate between mucosal mast cells and globule leucocytes have similar granule and surface properties. These observations, together with quantitative data, indicate that alterations in the granule structure of mucosal mast cells as a consequence of prolonged antigenic challenge give rise to mast cells in the epithelium which, in the past, have been commonly recognized as globule leucocytes.

Abomasum↗
PubMed1984

Stability of new electrical connections between adult Helisoma neurons is influenced by preexisting neuronal interactions.

The factors responsible for the selective stability of new electrical connections between regenerating, adult Helisoma neurons (5, 6) were examined. In particular the alternative hypotheses that the normal reduction in strength of a specific connection is dependent on the formation of a new stable connection or the maintenance of a preexisting connection were tested. To this end, single neurons were eliminated either by microdissection or photoinactivation. Formation of stable 5-5 [i.e., left neuron 5 (L5) to right neuron 5 (R5)] coupling was prevented by removal of a single neuron 5 soma. The time course of the normally transient neuron 5-4 connection in these ganglia, however, was the same as that of control preparations. Thus the 5-4 connection is transient even when stable 5-5 coupling is unable to develop. After removal of a single neuron 4 soma, however, the 5-4 connection was stabilized. This was despite the concurrent development of stable 5-5 coupling in these preparations. Similar results were obtained when neurons were eliminated by photoinactivation, a procedure that kills axonal processes in addition to the neuronal cell body. Morphological examination of untreated neurons by Lucifer Yellow CH stain showed that neurite outgrowth was not prevented by either of the techniques employed to eliminate single neurons. It is concluded that the development of the new, stable 5-5 electrical connection does not influence the transient nature of the 5-4 connection. The presence of both neurons 4, however, which have a preexisting connection, is required for reduction of 5-4 coupling. Thus preexisting neurons and/or their connections appear to play a role in the stability of new connections in this adult nervous system.

Animals↗
PubMed1984

Anaphylactic release of mucosal mast cell protease and its relationship to gut permeability in Nippostrongylus-primed rats.

The systemic secretion of rat mucosal mast cell protease (RMCPII) was examined in Nippostrongylus-primed rats injected intravenously with N. brasiliensis whole worm antigen. The secretory response in primed rats was both time- and dose-dependent whereas no RMCPII was present in the sera of naive rats challenged with antigen. RMCPII was detected in the sol and gel phases of intestinal perfusates, the release of enzyme into the gut lumen occurring very rapidly after challenge in immune rats. Mucosal permeability, assessed by measuring the passage of Evan's blue from the blood into the gut lumen was both time- and dose-dependent and reflected the combined capillary and epithelial permeability. Although the release of RMCPII into the gut lumen occurred more rapidly than the intraluminal accumulation of Evan's blue, these two events were highly correlated. There were, in addition significant correlations between the systemic and enteric secretion of RMCPII and the enteric accumulation of Evan's blue. These results indicate that RMCPII may have a role in altering intestinal mucosal permeability during systemic anaphylaxis in the rat.

Anaphylaxis↗
PubMed1984

Granulated intraepithelial lymphocytes: their relationship to mucosal mast cells and globule leucocytes in the rat.

The relationship between mucosal mast cells (MMC) in the intestinal lamina propria, and globule leucocytes (GL) and granulated lymphocytes (GIEL) within the epithelium was compared by analysing the constituents of their granules. Glycosaminoglycan, as well as serine esterase, were present in the granules of all three cell types and the antigenic relationship of these serine esterases to MMC-specific protease (RMCPII) was examined. This enzyme was detected by immunocytochemistry within MMC and GL granules, but not in GIEL. The concentration of RMCPII in preparations of epithelial and lamina propria isolates correlated significantly with the numbers of MMC/GL present within these tissues. RMCPII was detected in epithelial isolates, and in preparations of isolated GIEL, only when MMC and GL were present. These studies add further support to the view that MMC and GL are of a common lineage and strongly suggest that GIEL are unrelated to MMC/GL.

Animals↗
PubMed1983

Systemic release of mucosal mast-cell protease in primed rats challenged with Nippostrongylus brasiliensis.

The systemic secretion of a serine protease, rat mast-cell protease II (RMCPII), a major product of rat mucosal mast cells (MMC), was measured by a sensitive enzyme-linked immunosorbent assay (ELISA) in the sera of naive and primed rats challenged with the nematode N. brasiliensis. The systemic secretion of RMCPII was both time- and dose-dependent in primed rats (1-3 micrograms RMCPII/ml serum, 1 hr after challenge). Systemic release of RMCPII was slower and less pronounced in naive rats following intraduodenal challenge with 5-day-old worms. No RMCPII was detected in the sera of naive rats challenged with 4-day-old N. brasiliensis. Soluble worm antigen had no effect in naive rats, but when it was given intraduodenally or intravenously to primed rats, the serum levels of RMCPII 1 hr later were 10.5 micrograms/ml and 122 micrograms/ml, respectively. Few morphological changes were detected in MMC following worm challenge and the jejunal content of RMCPII was unaltered. A substantial reduction in the number of MMC occurred following intravenous injection of worm antigen, and the remaining cells were vacuolated and pale-staining, although granule exocytosis was not observed. Significant reduction in the jejunal content of RMCPII was also evident. These results demonstrate, unequivocally, that MMC are activated in response to N. brasiliensis challenge infection or to parasite antigens. In addition, the ability to detect secreted RMCPII in the sera of test animals provides a highly sensitive and uniquely selective assay to determine the participation of MMC in pathological reactions at mucosal surfaces.

Animals↗
PubMed1983

Immune exclusion, a mechanism of protection against the ovine nematode Haemonchus contortus.

The fate of exsheathed Haemonchus contortus larvae injected directly into the abomasal lumen was studied in groups of naive and hyperimmune sheep. Within 48 hours of challenge, more than 90 per cent of the larvae were lost from hyperimmune sheep. The larvae had a propensity to associate with the superficial mucus in both groups and, in naive sheep, approximately 50 per cent of the larvae entered glandular tissue within four hours of challenge. By contrast, although initially associated with the mucosal surface, larvae in immune sheep were excluded from the glandular tissues. It is postulated that the rapid loss of worms from the hyperimmune abomasum is a consequence of 'immune exclusion' and the possible mechanisms underlying this process are discussed.

Abomasum↗