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Laise Corthesy - One of the best experts on this subject based on the ideXlab platform.
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role of Secretory Immunoglobulin a and Secretory component in the protection of mucosal surfaces
Future Microbiology, 2010Co-Authors: Laise CorthesyAbstract:The contribution of Secretory Immunoglobulin A (SIgA) antibodies in the defense of mucosal epithelia plays an important role in preventing pathogen adhesion to host cells, therefore blocking dissemination and further infection. This mechanism, referred to as immune exclusion, represents the dominant mode of action of the antibody. However, SIgA antibodies combine multiple facets, which together confer properties extending from intracellular and serosal neutralization of antigens, activation of non-inflammatory pathways and homeostatic control of the endogenous microbiota. The sum of these features suggests that future opportunities for transvlational application from research-based knowledge to clinics include the mucosal delivery of bioactive antibodies capable of preserving immunoreactivity in the lung, gastrointestinal tract, the genito–urinary tract for the treatment of infections. This article covers topics dealing with the structure of SIgA, the dissection of its mode of action in epithelia lining d...
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Secretory Immunoglobulin a well beyond immune exclusion at mucosal surfaces
Immunopharmacology and Immunotoxicology, 2009Co-Authors: Laise CorthesyAbstract:At mucosal surfaces, Secretory IgA (SIgA) antibodies serve as the first line of defense against microorganisms through a mechanism called immune exclusion that prevents interaction of neutralized antigens with the epithelium. In addition, SIgA plays a role in the immune balance of the epithelial barrier through selective adhesion to M cells in intestinal Peyer's patches. This mediates the transepithelial retro-transport of the antibody and associated antigens from the intestinal lumen to underlying gut-associated organized lymphoid tissue. In Peyer's patches, SIgA-based immune complexes are internalized by underlying antigen-presenting cells, leaving the antigen with masked epitopes, a form that limits the risk of overwhelming the local immune protection system with danger signals. This translates into the onset of mucosal and systemic responses associated with production of anti-inflammatory cytokines and limited activation of antigen-presenting cells. In the gastrointestinal tract, SIgA exhibits thus properties of a neutralizing agent (immune exclusion) and of an immunopotentiator inducing effector immune responses in a noninflammatory context favorable to preserve local homeostasis.
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recombinant Secretory Immunoglobulin a in passive immunotherapy linking immunology and biotechnology
Current Pharmaceutical Biotechnology, 2003Co-Authors: Laise CorthesyAbstract:The use of monoclonal antibodies has become routine in the research and diagnostic laboratories, but the potential of antibody molecules in public health and medical applications is still far from its maximum. Most infections begin at mucosal surfaces, and this is certainly not only a stroke of good fortune if mother's milk serves as a natural delivery vehicle for antibodies protecting the gastrointestinal tract of nursing infants. Mammary gland or other mucous secretions containing numerous antibody specificities provide an efficient mean to immediately protect a mucosal surface against pathogens, which have never been encountered by the host. From a public health perspective, topical passive immunization of mucosal surfaces with monoclonal antibodies can block entry and transmission of bacteria, viruses, fungi and parasites that infect humans, and thus defeat some key immune evasion strategies designed by many pathogens. The chief antibody on most mucosal surfaces is Secretory Immunoglobulin A (SIgA), a polypeptide complex comprising dimeric IgA, the connecting J chain, and the Secretory component. The molecular stability, tetravalency, and strong anti-inflammatory properties make SIgA particularly well suited to fulfill the function of passive protective immunity when applied exogenously to mucosal surfaces. The review will give an overview of the basic concepts underlying mucosal immunity, present the molecular mechanisms whereby SIgA prevents mucosal infections, cover the last advances in the topic of recombinant SIgA production, and examine how structure-function relationship in SIgA will help designing molecules with novel properties for passive immunotherapy.
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Secretory Immunoglobulin a from mucosal protection to vaccine development
Biological Chemistry, 1999Co-Authors: Laise Corthesy, Francois SpertiniAbstract:Immune responses taking place in mucosal tissues are typified by Secretory Immunoglobulin A (S-IgA) molecules, which are assembled from proteins expressed in two cell lineages. The heavy and light chains as well as the J chain are produced in plasma cells, whereas the Secretory component (SC) is associated to the Immunoglobulin complex during transcytosis across the epithelial layer. S-IgA antibodies represent the predominant Immunoglobulin class in external secretions, and the best defined entity providing specific immune protection for mucosal surfaces by blocking attachment of bacteria and viruses. S-IgA constitutes greater than 80% of all antibodies produced in mucosa-associated lymphoid tissues in humans. The existence of a common mucosal immune system permits immunization on one mucosal surface to induce secretion of antigen-specific S-IgA at distant sites. In addition, S-IgA antibodies not only function in external secretions, but also exert their antimicrobial properties within the epithelial cell during transport across the epithelium. Passive mucosal delivery of monoclonal IgA molecules neutralizes pathogens responsible for gastrointestinal and respiratory infections. Mucosal and systemic immunity can be achieved by orally administered recombinant S-IgA molecules carrying a protective bacterial epitope within the SC polypeptide primary sequence.
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a pathogen specific epitope inserted into recombinant Secretory Immunoglobulin a is immunogenic by the oral route
Journal of Biological Chemistry, 1996Co-Authors: Laise Corthesy, Maria R Neutra, Muriel Kaufma, Armelle Phalipo, Manuel C Peitsch, Jeanpierre KraehenbuhlAbstract:Abstract Oral administration of rabbit Secretory IgA (sIgA) to adult BALB/c mice induced IgA+, IgM+, and IgG+ lymphoblasts in the Peyer's patches, whose fusion with myeloma cells resulted in hybridomas producing IgA, IgM, and IgG1 antibodies to the Secretory component (SC). This suggests that SC could serve as a vector to target protective epitopes into mucosal lymphoid tissue and elicit an immune response. We tested this concept by inserting a Shigella flexneri invasin B epitope into SC, which, following reassociation with IgA, was delivered orally to mice. To identify potential insertion sites at the surface of SC, we constructed a molecular model of the first and second Ig-like domains of rabbit SC. A surface epitope recognized by an SC-specific antibody was mapped to the loop connecting the E and F β strands of domain I. This 8-amino acid sequence was replaced by a 9-amino acid linear epitope from S. flexneri invasin B. We found that cellular trafficking of recombinant SC produced in mammalian CV-1 cells was drastically altered and resulted in a 50-fold lower rate of secretion. However, purification of chimeric SC could be achieved by Ni2+-chelate affinity chromatoraphy. Both wild-type and chimeric SC bound to dimeric IgA, but not to monomeric IgA. Reconstituted sIgA carrying the invasin B epitope within the SC moiety triggers the appearance of seric and salivary invasin B-specific antibodies. Thus, neo-antigenized sIgA can serve as a mucosal vaccine delivery system inducing systemic and mucosal immune responses.
Ichiro Kono - One of the best experts on this subject based on the ideXlab platform.
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salivary Secretory Immunoglobulin a secretion increases after 4 weeks ingestion of chlorella derived multicomponent supplement in humans a randomized cross over study
Nutrition Journal, 2011Co-Authors: Takeshi Otsuki, Kazuhiro Shimizu, Motoyuki Iemitsu, Ichiro KonoAbstract:Chlorella, a unicellular green alga that grows in fresh water, contains high levels of proteins, vitamins, minerals, and dietary fibers. Some studies have reported favorable immune function-related effects on biological secretions such as blood and breast milk in humans who have ingested a chlorella-derived multicomponent supplement. However, the effects of chlorella-derived supplement on mucosal immune functions remain unclear. The purpose of this study was to investigate whether chlorella ingestion increases the salivary Secretory Immunoglobulin A (SIgA) secretion in humans using a blind, randomized, crossover study design. Fifteen men took 30 placebo and 30 chlorella tablets per day for 4 weeks separated by a 12-week washout period. Before and after each trial, saliva samples were collected from a sterile cotton ball that was chewed after overnight fasting. Salivary SIgA concentrations were measured using ELISA. Compliance rates for placebo and chlorella ingestions were 97.0 ± 1.0% and 95.3 ± 1.6%, respectively. No difference was observed in salivary SIgA concentrations before and after placebo ingestion (P = 0.38). However, salivary SIgA concentrations were significantly elevated after chlorella ingestion compared to baseline (P < 0.01). No trial × period interaction was identified for the saliva flow rates. Although the SIgA secretion rate was not affected by placebo ingestion (P = 0.36), it significantly increased after 4-week chlorella ingestion than before intake (P < 0.01). These results suggest 4-week ingestion of a chlorella-derived multicomponent supplement increases salivary SIgA secretion and possibly improves mucosal immune function in humans.
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a rat model of saliva Secretory Immunoglobulin a suppression caused by intense exercise
Scandinavian Journal of Medicine & Science in Sports, 2008Co-Authors: Fuminori Kimura, Katsuji Aizawa, Kenneth K Tanabe, Kazuhiro Shimizu, Hoseong Lee, Takayuki Akimoto, Takao Akama, Ichiro KonoAbstract:We aimed to develop a valid model of immunosuppression induced by intense exercise in rats. Rats were divided into three groups. In the rest (Rest) group, saliva was collected from resting rats on 4 consecutive days. In the exercise (Ex) group, rats ran on a treadmill until exhaustion (exercise time: 60.0 +/- 3.7 min), and their saliva was collected before and after exercise; the salivary glands were removed after exercise. In the control (Con) group, saliva collection and gland removal were also performed, but the rats did not exercise. Secretory Immunoglobulin A (SIgA) concentrations in saliva and polymeric Immunoglobulin receptor (pIgR) mRNA expression in the glands were measured. There was no significant change in SIgA concentration in the Rest group over 4 days. In the Ex group, SIgA concentration decreased significantly after exercise compared with before, whereas there was no significant change in the Con group. The expression of pIgR mRNA was significantly lower in the Ex group post-exercise than in the Con group. Our procedure for saliva collection appeared suitable, and the exercise-induced SIgA suppression was probably caused by a decline in pIgR mRNA expression. We propose to use this reproducible and reliable rat model of exercise-induced SIgA suppression in future studies.
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effects of exercise age and gender on salivary Secretory Immunoglobulin a in elderly individuals
Exercise Immunology Review, 2007Co-Authors: Kazuhiro Shimizu, Fuminori Kimura, Takayuki Akimoto, Takao Akama, Takeshi Otsuki, Takahiko Nishijima, Shinya Kuno, Ichiro KonoAbstract:The influence of age and gender on salivary Secretory Immunoglobulin A (SIgA) in response to moderate exercise training was studied in 158 elderly subjects. Subjects were assigned to an exercise training group (EXC: 51 males, 74 females) or a non-exercise control group (CON: 11 males, 22 females). The subjects in each group were separated into four age-gender subgroups (60-69-yr-old males, over 70-yr-old males, 60-69-yr-old females, over 70-yr-old females) and compared by age and gender. Subjects in EXC participated in exercise sessions 5-days a week for 6 months. Saliva samples were collected both before and after the study period. The SIgA secretion rates were significantly increased after training (p < 0.05) in all the age-gender subgroups of EXC (60-69 males: 41%, over 70 males: 55%, 60-69 females: 40%, over 70 females: 38%); no age- or gender-related differences were observed. On the other hand, none of the age-gender subgroups of CON showed significant changes in the SIgA secretion rate; also, there were no age- or gender-related differences. In conclusion, enhancement of mucosal immune function following regular moderate exercise training occurs in elderlies in their 60s and over 70 years, and in both, males and females.
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daily changes of salivary Secretory Immunoglobulin a and appearance of upper respiratory symptoms during physical training
Journal of Sports Medicine and Physical Fitness, 2006Co-Authors: D Nakamura, Takayuki Akimoto, S Suzuki, Ichiro KonoAbstract:AIM It is well known that highly trained athletes suffer from a high incidence of upper respiratory tract infections (URTI). Secretory Immunoglobulin A (SIgA) is a major effector of mucosal surface protection against microorganisms causing URTI. Although several studies have investigated the relationship between falls in SIgA levels and appearance of URTI symptoms, the relationship is not yet clear. METHODS We prospectively investigated the relationship between daily changes in SIgA and appearance of URTI symptoms in collegiate soccer players during a training period of 2 months. RESULTS Five of 12 subjects exhibited URTI symptoms during the study period. The SIgA level did not significantly decrease before appearance of URTI symptoms. However, the saliva flow rate and SIgA secretion rate tended to decrease 3 days before the appearance of URTI symptoms compared to that in the non-infection period (31.3+/-19, -42.2+/-20.6%, respectively). CONCLUSIONS We could not demonstrate a significant relationship between decreased SIgA levels and appearance of URTI symptoms during the training period. However, our findings suggest that monitoring of SIgA secretion rate may be useful for assessment of risk status of athletes for URTI.
Frank Hucklebridge - One of the best experts on this subject based on the ideXlab platform.
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acute reduction in Secretory Immunoglobulin a following smoking cessation
Psychoneuroendocrinology, 2004Co-Authors: Michael Usshe, Angela Clow, Philip D Evans, Robe Wes, Andrew Steptoe, Andy Mcewe, Frank HucklebridgeAbstract:Smokers report an increase in upper respiratory infections in the early phase of stopping smoking. One possible cause is a depletion in Secretory Immunoglobulin A (S-IgA) which has been observed in one study. The present study sought to establish this finding in smokers using nicotine patches. Ninety-two smokers, trying to stop smoking, were assessed whilst smoking and for up to six weeks of abstinence. All smokers were prescribed 15 mg 16-h nicotine patches. Among abstinent smokers, changes in S-IgA and saliva volume were assessed. During the preliminary analyses, we observed that for the pre-smoking cessation measure a longer time since the last cigarette was significantly related to lower S-IgA levels (P=0.006). Consequently, the main analysis, of changes in S-IgA from pre-cessation to post-cessation, was confined to those who had smoked within 0.5-1.5 h of the pre-cessation measure (n=51). There was a significant decline in S-IgA, relative to pre-smoking abstinence levels, following abstinence of one day (P=0.027), but levels returned to pre-abstinence values after one week. There was no evidence of any significant changes in saliva volume following smoking cessation, relative to pre-cessation levels. Users of 15 mg patches are likely to experience a decline in S-IgA levels on the first day of smoking cessation, independent of saliva volumes, and this decline in S-IgA is likely to occur acutely, within the first few hours of smoking abstinence. This acute drop in S-IgA appears to stem from a factor other than depletion of nicotine from the body. The observed decrease in S-IgA may help to explain the increased susceptibility of smokers to upper respiratory tract infections in the immediate post-cessation period.
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modulation of Secretory Immunoglobulin a in saliva response to manipulation of mood
Biological Psychology, 2000Co-Authors: Frank Hucklebridge, Angela Clow, Shirley Lambe, David Warburto, Philip D Evans, N SherwoodAbstract:Secretory Immunoglobulin A (sIgA) measured in saliva, an index of mucosal immunity, has repeatedly been shown to be sensitive to psychological variables. Chronic stress is downregulatory whereas an acute psychological challenge induces mobilisation. We examined whether an acute manipulation of mood to induce negative hedonic tone would be downregulatory, as in the chronic stress paradigm and further, whether induction of positive mood might have opposite effects. Two separate experiments were conducted. In the first, mood manipulation was by mental recall and in the second by music. For both sIgA concentration and sIgA secretion rate there was a significant elevation in response to the mood manipulation by recall regardless of hedonic tone. There was some evidence that for sIgA secretion rate the response was more pronounced for positive mood. Mood induction by music also resulted in significant elevations in sIgA concentration and secretion rate and responses were not distinguished by mood valence. None of the mood induction procedures was associated with changes in free cortisol. In these studies, we found no evidence that transient lowering of mood was downregulatory for salivary sIgA. The predominant finding was of sIgA mobilisation.
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the relationship between salivary Secretory Immunoglobulin a and cortisol neuroendocrine response to awakening and the diurnal cycle
International Journal of Psychophysiology, 1998Co-Authors: Frank Hucklebridge, Angela Clow, Philip D EvansAbstract:The level of Secretory Immunoglobulin A (sIgA) measured in saliva is downregulated during periods of chronic stress. In contrast, the response to an acute stress challenge is a transient increase. The process of awakening is associated with stress neuroendocrine activation characterised by increases in salivary cortisol. We therefore examined if this period of hypothalamic–pituitary–adrenal (HPA) activation was associated with changes in salivary sIgA. Associations of sIgA with the diurnal cortisol cycle were also investigated in a separate study. The awakening cortisol response was measured in 30 healthy day-active young adults. There was a marked elevation from the first awakening level over the succeeding 30 min. SIgA showed the opposite response with a marked fall from the highest first awakening concentration in the same samples over the same period. The cortisol rise was significantly correlated with the sIgA fall (r=0.42). Salivary sIgA showed a similar diurnal cycle to cortisol in a study on eight healthy young adults. An early morning acrophase was followed by a decline to a stable base some 6 h after awakening. The physiological significance of these relationships and possible implications for vulnerability to infection are discussed.
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Secretory Immunoglobulin a and cardiovascular reactions to mental arithmetic and cold pressor
Psychophysiology, 1998Co-Authors: Gonneke Willemse, Christophe Ring, Douglas Carroll, Phil Evans, Angela Clow, Frank HucklebridgeAbstract:Secretory Immunoglobulin A (sIgA) in saliva and cardiovascular reactions to mental arithmetic and cold pressor tasks were recorded in 16 healthy young men on two sessions, 4 weeks apart. Both tasks elicited significant increases in sIgA secretion rate, reflecting increases in both salivary volume and sIgA concentration. Whereas mental arithmetic elicited a mixed pattern of alpha- and beta-adrenergic cardiovascular reactions, the pattern of reactions to cold pressor was predominantly alpha-adrenergic. Task levels of sIgA secretion rate, sIgA concentration, and saliva volume showed moderate to high test-retest reliability (r = .52-.83), although test-retest correlations were less impressive for change scores (r = -.19-.53). The pattern of correlations between change in sIgA secretion rate and cardiovascular reactivity variables was inconsistent.
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Secretory Immunoglobulin a and cardiovascular responses to acute psychological challenge
International Journal of Behavioral Medicine, 1996Co-Authors: Douglas Carroll, Gonneke Willemse, Christophe Ring, Phil Evans, Jo Shrimpto, Frank HucklebridgeAbstract:Cardiovascular activity and Secretory Immunoglobulin A (sIgA) in saliva were recorded at rest, during a 30-min computer game task, and during subsequent recovery. Blood pressure (BP) rose and remained elevated during the task and returned to resting levels during recovery. This pressor response was produced by increased total peripheral resistance rather than increased cardiac output. SIgA secretion rate also increased during the task, although the effect proved significant only toward the end of the task. As such, the data provide preliminary indication that sIgA is sensitive to acute psychological challenge in the laboratory. Although correlational analyses revealed that sIgA reactions were stable, they were not significantly correlated with pressor reactions. The influence of task uncertainty was explored by comparing individuals who had previously played the computer game with those who had not. Task-induced increases in BP and sIgA were a feature of individuals new to the computer game. In contrast to these novice players, experienced players showed minimal increases in BP and no increases in sIgA.
Douglas Carroll - One of the best experts on this subject based on the ideXlab platform.
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Secretory Immunoglobulin a reactions to prolonged mental arithmetic stress inter session and intra session reliability
Biological Psychology, 2002Co-Authors: Christophe Ring, Mark T Drayso, Dunca G Walkey, Sarah Dale, Douglas CarrollAbstract:Although previous evidence suggests that mucosal immunity may be influenced by mental stress, the importance of the duration of stress exposure on Secretory Immunoglobulin A (sIgA) has yet to be fully elucidated. Salivary sIgA and cardiovascular activity were measured at rest, following 14 and 28 min of mental arithmetic, and after recovery in 24 men and women on two sessions 2-4 days apart. Mental arithmetic was, on both sessions and after both the early and late phases of the task, associated with increases in sIgA concentration and sIgA secretion rate compared to rest and recovery. Task levels of sIgA concentration and sIgA secretion rate showed moderate to high intra- and inter-session test-retest reliability, while test-retest reliability was lower for change scores. Blood pressure and pulse rate were also elevated by the mental stress task, although correlational analyses revealed that stress-induced changes in sIgA were not related to cardiovascular reactions.
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cardiovascular and Secretory Immunoglobulin a reactions to humorous exciting and didactic film presentations
Biological Psychology, 2000Co-Authors: Lesley K Harriso, Christophe Ring, Douglas Carroll, Victoria E Urns, Anna R Corkill, Clare M Harriso, Mark T DraysoAbstract:Secretory Immunoglobulin A (sIgA) in saliva and cardiovascular activity were measured at rest and in response to three film extracts varying in affective content. Subjective ratings of film impact confirmed a priori assumptions; the humorous film was rated as funnier than the other two films, the didactic film as more boring than the other two films, and the exciting film as more exciting and more stressful than the other two films. The films elicited distinct patterns of cardiovascular autonomic activity. The exciting film provoked changes characteristic of beta-adrenergic activation: increased systolic blood pressure (SBP); heart rate (HR); cardiac output (CO); and shortened pre-ejection period (PEP). The didactic film had little impact on cardiovascular activity. While an increase in total peripheral resistance (TPR) occurred, the humorous film was largely notable for a reduction in beta-adrenergic drive, as evidenced by reduced CO and a lengthening of PEP. In contrast to previous research reporting a rise in sIgA particular to humorous exposures, the sIgA secretion rate, although enhanced by exposure to the films, did not vary with film content.
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Secretory Immunoglobulin a and cardiovascular activity during mental arithmetic effects of task difficulty and task order
Biological Psychology, 2000Co-Authors: Gonneke Willemse, Christophe Ring, Sam Mckeeve, Douglas CarrollAbstract:Secretory Immunoglobulin A (sIgA) in saliva and cardiovascular activity were measured at rest and during mental arithmetic. Task difficulty was manipulated by presenting easy, hard, and impossible versions of the mental arithmetic task in counterbalanced order, while task novelty was operationalised as order of presentation (i.e. first, second, third). Mental arithmetic elicited significant increases in sIgA concentration and sIgA secretion rate, as well as significant cardiovascular effects. Performance decreased and rated difficulty increased with increasing task difficulty. However, sIgA and cardiovascular activity, with the exception of diastolic blood pressure, were insensitive to variations in task difficulty. In contrast, sIgA concentration and a broad range of cardiovascular variables were influenced by task novelty, with more pronounced activity characterising the task version presented first, irrespective of its level of difficulty. Task novelty would seem to be a more important determinant of sIgA and cardiovascular activity than task difficulty.
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Secretory Immunoglobulin a and cardiovascular activity during mental arithmetic and paced breathing
Psychophysiology, 1999Co-Authors: Christophe Ring, Gonneke Willemse, Douglas Carroll, Jonatha Cooke, Adria Ferraro, Mark T DraysoAbstract:The role of the autonomic nervous system in Secretory Immunoglobulin A (sIgA) responses to laboratory challenge was explored in a study in which sIgA and cardiovascular activity were recorded at rest and during mental arithmetic and paced breathing. These tasks were selected to preferentially engage the sympathetic and parasympathetic nervous systems, respectively. Mental arithmetic elicited a mixed pattern of increased alpha- and beta-adrenergic activity and a reduction in parasympathetic activity; diastolic blood pressure, total peripheral resistance, and systolic blood pressure increased, preejection period shortened, and heart rate variability decreased. In contrast, paced breathing primarily elicited an increase in parasympathetic activity; heart rate variability increased. Mental arithmetic also provoked an increase in sIgA concentration but no change in saliva volume, whereas paced breathing affected neither sIgA concentration nor saliva volume. These data suggest that sIgA responses to laboratory challenges are mediated by sympathetic rather than parasympathetic processes.
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Secretory Immunoglobulin a and cardiovascular reactions to mental arithmetic cold pressor and exercise effects of beta adrenergic blockade
Psychophysiology, 1999Co-Authors: Alexandra Winze, Gonneke Willemse, Christophe Ring, Douglas Carroll, Mark T Drayso, M J KendallAbstract:We investigated the influence of sympathetic nervous system processes on mucosal immunity by comparing the effects of beta-adrenoceptor blockade with 40 mg propranolol and placebo on Secretory Immunoglobulin A (sIgA) at rest and during paced serial arithmetic, cold pressor, and submaximal cycling. These tasks produced patterns of cardiovascular activity indicative of combined alpha- and beta-adrenergic, alpha-adrenergic, and beta-adrenergic activation, respectively. The effectiveness of the beta blockade was confirmed by the attenuation under propranolol of the shortening of the cardiac preejection period and the tachycardia elicited by mental arithmetic and exercise. The cold pressor test did not affect sIgA under either the placebo or the propranolol. Mental arithmetic increased sIgA concentration, and this increase was not blocked by propranolol. Exercise elicited increases in both sIgA concentration and sIgA secretion rate, which were not diminished by beta blockade. These data suggest that sIgA is not regulated by beta-adrenergic mechanisms.
Christophe Ring - One of the best experts on this subject based on the ideXlab platform.
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Secretory Immunoglobulin a reactions to prolonged mental arithmetic stress inter session and intra session reliability
Biological Psychology, 2002Co-Authors: Christophe Ring, Mark T Drayso, Dunca G Walkey, Sarah Dale, Douglas CarrollAbstract:Although previous evidence suggests that mucosal immunity may be influenced by mental stress, the importance of the duration of stress exposure on Secretory Immunoglobulin A (sIgA) has yet to be fully elucidated. Salivary sIgA and cardiovascular activity were measured at rest, following 14 and 28 min of mental arithmetic, and after recovery in 24 men and women on two sessions 2-4 days apart. Mental arithmetic was, on both sessions and after both the early and late phases of the task, associated with increases in sIgA concentration and sIgA secretion rate compared to rest and recovery. Task levels of sIgA concentration and sIgA secretion rate showed moderate to high intra- and inter-session test-retest reliability, while test-retest reliability was lower for change scores. Blood pressure and pulse rate were also elevated by the mental stress task, although correlational analyses revealed that stress-induced changes in sIgA were not related to cardiovascular reactions.
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cardiovascular and Secretory Immunoglobulin a reactions to humorous exciting and didactic film presentations
Biological Psychology, 2000Co-Authors: Lesley K Harriso, Christophe Ring, Douglas Carroll, Victoria E Urns, Anna R Corkill, Clare M Harriso, Mark T DraysoAbstract:Secretory Immunoglobulin A (sIgA) in saliva and cardiovascular activity were measured at rest and in response to three film extracts varying in affective content. Subjective ratings of film impact confirmed a priori assumptions; the humorous film was rated as funnier than the other two films, the didactic film as more boring than the other two films, and the exciting film as more exciting and more stressful than the other two films. The films elicited distinct patterns of cardiovascular autonomic activity. The exciting film provoked changes characteristic of beta-adrenergic activation: increased systolic blood pressure (SBP); heart rate (HR); cardiac output (CO); and shortened pre-ejection period (PEP). The didactic film had little impact on cardiovascular activity. While an increase in total peripheral resistance (TPR) occurred, the humorous film was largely notable for a reduction in beta-adrenergic drive, as evidenced by reduced CO and a lengthening of PEP. In contrast to previous research reporting a rise in sIgA particular to humorous exposures, the sIgA secretion rate, although enhanced by exposure to the films, did not vary with film content.
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Secretory Immunoglobulin a and cardiovascular activity during mental arithmetic effects of task difficulty and task order
Biological Psychology, 2000Co-Authors: Gonneke Willemse, Christophe Ring, Sam Mckeeve, Douglas CarrollAbstract:Secretory Immunoglobulin A (sIgA) in saliva and cardiovascular activity were measured at rest and during mental arithmetic. Task difficulty was manipulated by presenting easy, hard, and impossible versions of the mental arithmetic task in counterbalanced order, while task novelty was operationalised as order of presentation (i.e. first, second, third). Mental arithmetic elicited significant increases in sIgA concentration and sIgA secretion rate, as well as significant cardiovascular effects. Performance decreased and rated difficulty increased with increasing task difficulty. However, sIgA and cardiovascular activity, with the exception of diastolic blood pressure, were insensitive to variations in task difficulty. In contrast, sIgA concentration and a broad range of cardiovascular variables were influenced by task novelty, with more pronounced activity characterising the task version presented first, irrespective of its level of difficulty. Task novelty would seem to be a more important determinant of sIgA and cardiovascular activity than task difficulty.
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Secretory Immunoglobulin a and cardiovascular activity during mental arithmetic and paced breathing
Psychophysiology, 1999Co-Authors: Christophe Ring, Gonneke Willemse, Douglas Carroll, Jonatha Cooke, Adria Ferraro, Mark T DraysoAbstract:The role of the autonomic nervous system in Secretory Immunoglobulin A (sIgA) responses to laboratory challenge was explored in a study in which sIgA and cardiovascular activity were recorded at rest and during mental arithmetic and paced breathing. These tasks were selected to preferentially engage the sympathetic and parasympathetic nervous systems, respectively. Mental arithmetic elicited a mixed pattern of increased alpha- and beta-adrenergic activity and a reduction in parasympathetic activity; diastolic blood pressure, total peripheral resistance, and systolic blood pressure increased, preejection period shortened, and heart rate variability decreased. In contrast, paced breathing primarily elicited an increase in parasympathetic activity; heart rate variability increased. Mental arithmetic also provoked an increase in sIgA concentration but no change in saliva volume, whereas paced breathing affected neither sIgA concentration nor saliva volume. These data suggest that sIgA responses to laboratory challenges are mediated by sympathetic rather than parasympathetic processes.
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Secretory Immunoglobulin a and cardiovascular reactions to mental arithmetic cold pressor and exercise effects of beta adrenergic blockade
Psychophysiology, 1999Co-Authors: Alexandra Winze, Gonneke Willemse, Christophe Ring, Douglas Carroll, Mark T Drayso, M J KendallAbstract:We investigated the influence of sympathetic nervous system processes on mucosal immunity by comparing the effects of beta-adrenoceptor blockade with 40 mg propranolol and placebo on Secretory Immunoglobulin A (sIgA) at rest and during paced serial arithmetic, cold pressor, and submaximal cycling. These tasks produced patterns of cardiovascular activity indicative of combined alpha- and beta-adrenergic, alpha-adrenergic, and beta-adrenergic activation, respectively. The effectiveness of the beta blockade was confirmed by the attenuation under propranolol of the shortening of the cardiac preejection period and the tachycardia elicited by mental arithmetic and exercise. The cold pressor test did not affect sIgA under either the placebo or the propranolol. Mental arithmetic increased sIgA concentration, and this increase was not blocked by propranolol. Exercise elicited increases in both sIgA concentration and sIgA secretion rate, which were not diminished by beta blockade. These data suggest that sIgA is not regulated by beta-adrenergic mechanisms.
