Secretory Immunoglobulin A Secretion Research Articles

Xixin Decoction regulates Th17/Treg balance and transcription factor expression in senescence-accelerated mouse-prone

This study aims to investigate the effect of Xixin Decoction on the T helper 17 cell(Th17)/regulatory T cell(Treg) ba-lance of intestinal mucosa and the expression of related transcription factors in the senescence-accelerated mouse-prone 8(SAMP8) model. Fifty 14-week male mice of SAMP8 were randomized by the random number table method into model group, probiotics group, and high-, medium-, and low-dose Xixin Decoction groups, with 10 mice in each group. Ten 14-week male mice of senescence-acce-lerated mouse-resistant 1(SAMR1) served as control group. After 10 weeks of feeding, the mice were administrated with correspon-ding drugs for 10 weeks. Morris water maze test was carried out to examine the learning and memory abilities of mice. Enzyme-linked immunosorbent assay(ELISA) was employed to determine the content of secretory immunoglobulin A(SIgA) in the intestinal mucosa, and flow cytometry to detect the percentage content of Th17 and Treg in the intestinal mucosa. Western blot was performed to determine the protein levels of retinoid-related orphan receptor gamma t(RORγt) and forkhead box p3(Foxp3) in the mouse colon tissue. Compared with control group, the escape latency of mice in model group was significantly prolonged(P<0.01), and the number of times of crossing the platform and the residence time in the target quadrant were significantly reduced within 60 s(P<0.01), intestinal mucosal SIgA content was significantly decreased(P<0.01), Th17 content was increased(P<0.05), Treg content was decreased(P<0.01), the expression of RORγt protein was increased and Foxp3 protein was decreased in colon(P<0.01). Compared with the model group, high-dose Xixin Decoction group improved the learning and memory ability(P<0.05 or P<0.01). Probiotics group and high-and medium-dose Xixin Decoction group increased the content of SIgA in intestinal mucosa(P<0.05 or P<0.01), decreased percentage content of Th17 and increased the percentage content of Treg in intestinal mucosa(P<0.05 or P<0.01). Furthermore, they down-regulated the protein level of RORγt and up-regulated the protein level of Foxp3 in the intestinal mucosa(P<0.01). In conclusion, Xixin Decoction may act on intestinal mucosal immune barrier, affect gut-brain information exchange, and improve the learning and memory ability of SAMP8 by promoting SIgA secretion and regulating the Th17/Treg balance and the expression of RORγt and Foxp3.

Sex differences in mood, hormone and immune response to combatives training in West Point Cadets

Hand-to-hand combat training, known as combatives, instructs Soldiers in close-quarters combat techniques and how to cope with stress, understand controlled physical aggression, and develop self-confidence when engaged in such activities. Limited research in combat sports suggests men and women may respond to combatives stress differently. Given the increasing integration of women into close combat roles in the military, investigation of sex differences in the physiological and psychological response to combatives among military-trained personnel is warranted. PurposeThis study was designed to identify sex differences in stress and gonadal hormones, mucosal immunity, and mood states in a military combatives training course. MethodsU.S. Military Academy Cadets (men = 144, women = 37) enrolled in a 2-month Combat Applications Course at West Point completed the Profile of Mood States and Competitive State Anxiety Inventory-2 and provided salivary samples at baseline prior to the course, and immediately prior to their midterm and final combat matches. Combat matches were gender- and weight-matched. Additional salivary samples were collected immediately following the first midterm and final matches. Salivary cortisol, testosterone, secretory immunoglobulin A (SIgA) and estradiol (women only) were measured via immunoassay. Men and women were compared over time with linear mixed effects models. ResultsIn both men and women, confusion, tension, anger, cognitive anxiety, somatic anxiety, and self-confidence increased throughout the course whereas friendliness and SIgA secretion rate decreased (all p < 0.05). Compared to women, men had a greater acute increase in cortisol from pre- to post-match (p = 0.043). Prior to the final match, women displayed higher ratings of tension (20.5 ± 9.3 vs. 16.0 ± 8.6) and cortisol (0.6 ± 0.3 vs. 0.4 ± 0.3 µg/dL) than men (all p < 0.05). After controlling for previous combative experience, ratings of tension did not differ by sex but remained elevated prior to midterm and final compared to baseline. ConclusionCombatives training elicited significant psychological and physiological stress and decreased mucosal immunity in both men and women. Women exhibited higher tension at the final match, likely due to lack of previous combative experience. Self-confidence increased from baseline suggesting that the skills learned may help Cadets prepare for combatives and other activities that require controlled aggression.

Changes in nasal, pharyngeal and salivary secretory IgA levels in patients with COVID-19 and the possibility of correction of their secretion using combined intranasal and oral administration of a pharmaceutical containing antigens of opportunistic microorganisms.

Although extensive research has been conducted on the role of local immunity in patients with SARS-CoV-2, little is known about the production and concentrations of secretory IgA (SIgA) in different mucosal compartments. This article aims to assess the secretion of SIgA in the nasal and pharyngeal compartments and saliva of patients with COVID-19 and to investigate the possibility and efficiency of correction of their secretion using combined intranasal and oral administration of a pharmaceutical containing antigens of opportunistic microorganisms. This study included 78 inpatients, aged between 18 and 60 years, who had confirmed COVID-19 with moderate lung involvement. The control group (n=45) received basic therapy, and the treatment group (n=33) was additionally administered the bacteria-based pharmaceutical Immunovac VP4 from day 1 to day 10 of hospitalization. SIgA levels were measured by ELISA at baseline and on days 14 and 30. No systemic or local reactions associated with Immunovac VP4 were reported. We observed a statistically significant reduction in the duration of fever and hospitalization in patients who received Immunovac VP4 compared with those from the control group (p=0.03 and p=0.05, respectively). Changes over time in SIgA levels in nasal swabs were found to be significantly different in the two treatment groups (F=7.9, p[78.0]<0.001). On day 14 of observation, patients in the control group showed a statistically significant reduction in SIgA levels from baseline (p=0.02), whereas patients in the Immunovac VP4 group had stable SIgA levels (p=0.07). On day 30 after the start of treatment, there was a statistically significant increase in SIgA levels in the Immunovac VP4 group compared with baseline (from 77.7 (40.5-98.7) μg/L to 113.4 (39.8-156.7) μg/L; p=0.05) and the levels measured on day 14 (from 60.2 (23.3-102.9) μg/L to 113.4 (39.8-156.7) μg/L; p=0.03). The control group showed a statistically significant decrease in levels of nasal SIgA (to 37.3) on day 30 (p=0.007 for comparison with baseline values and p=0.04 for comparison with levels measured on day 14). Changes over time in SIgA levels measured in pharyngeal swabs were also different between the two treatment groups, and this difference reached statistical significance (F=6.5, p[73.0]=0.003). In the control group, this parameter did not change throughout the study (p=0.17 for a comparison between the levels measured on day 14 and the baseline values, and p=0.12 for a comparison between the levels measured on day 30 and the baseline values). In the Immunovac VP4 group, there was a statistically significant increase from baseline in SIgA levels on study day 30: from 1.5 (0.2-16.5) μg/L to 29.8 (3.6-106.8) μg/L (p=0.02). Changes over time in salivary SIgA did not show a significant difference between study groups (F=0.3, p[66.3]=0.75). As part of combination therapy, the bacteria-based immunostimulant agent Immunovac VP4 increases SIgA levels in the nasal and pharyngeal compartments and induces clinical improvement. Induced mucosal immunity is central to the prevention of respiratory infections, particularly in patients with post-COVID-19 syndrome.

Mahuang Xixin Fuzi decoction protects the BALB/c-nude mice infected with influenza A virus by reducing inflammatory cytokines storm and weakly regulating SIgA immune response

Mahuang Xixin Fuzi Decoction (MXF), as a classical prescription of traditional Chinese medicine (TCM), has been used to treat the immunocompromised individuals infected with influenza A virus (IAV). The study aims to explore the regulatory of MXF on inflammation and secretory immunoglobulin A (SIgA) antibodies immune response in BALB/c-nude mice infected with IAV. The BALB/c-nude mice were infected with IAV, then different dosages of MXF were orally administrated to the mice. The weight, rectal temperature, spontaneous activity, spleen index, lung index, pathological changes of lung tissues, and the relative mRNA expression level of H1N1 M gene were measured for the purpose of valuing the antiviral effect of MXF. The expression levels of cytokines in lungs and immunoglobulin A (IgA) in serum of BALB/c-nude mice were determined with Cytometric Bead Array System (CBA). SIgA in bronchoalveolar lavage fluids (BALF) was detected with Enzyme-linked Immunosorbent Assay (ELISA). The mRNA and protein expression levels of B cell activating factor (BAFF), chemokine receptors 10 (CCR10), and polymeric immunoglobulin receptor (pIgR) in the lung tissues, which are related to the secretion of SIgA, were determined by using RT-PCR and Western blot. MXF could alleviate the clinical features and reduce the severity of viral lung lesions, including improving the body weight, rectal temperature and spontaneous activity of nude mice infected with IAV, increasing spleen index, decreasing lung index, alleviating pathological damage, and decreasing the relative expression level of H1N1 M gene. Levels of pro-inflammatory cytokines, including interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-2 (IL-2), interleukin-12p70 (IL-12p70), and interleukin-17A (IL-17A) were also significantly decreased after treatment with MXF. Interferon-γ (IFN-γ), an antiviral cytokine, was significantly up-regulated in high dose MXF (3.12g/kg) group. Moreover, after MXF treatment, the expressions of SIgA in BALF and IgA in serum were both at relatively low levels. And the mRNA and protein expressions of BAFF, CCR10, and pIgR were significantly decreased after treatment with MXF. MXF has obviously protective effects on BALB/c-nude mice infected with IAV by inhibiting virus replication, calming inflammatory cytokine storm, and regulating SIgA immune response weakly.

The effect of inulin-type fructans on the intestinal immune function of antibiotic-treated mice.

This study aimed to evaluate the effect of supplementation with inulin-type fructans (ITFs) on the intestinal immune function in the context of dysbiosis resulting from antibiotic cocktail (ABx) treatment. BALB/c mice (8-9weeks of age) were treated with an ABx for 3weeks and then allowed to recover spontaneously or with ITF supplementation (5%) for 4weeks. Our results showed that ABx treatment can induce gut microbiota dysbiosis and intestinal inflammation in mice. After 4weeks of recovery, ITF supplementation restored the composition of the intestinal microbial community. However, compared with spontaneous recovery, ITF supplementation delayed inflammation recovery in the intestine and upregulated diamine oxidase (DAO) activity and increased lipopolysaccharide (LPS) content in serum. In addition, ITF supplementation delayed the regulatory T (Treg) cell and B cell recovery in the lamina propria (LP). Furthermore, compared with spontaneous recovery, ITF supplementation inhibited the relative expression of certain proinflammatory genes, such as for inducible nitric oxide synthase (iNOS) and tumour necrosis factor α (Tnf-α), in the colon, but it reduced the secretion of the anti-inflammatory mediator transforming growth factor β1 (TGF-β1) in serum, reduced the secretion of secretory immunoglobulin A (SIgA) in the colon and promoted the secretion of the proinflammatory cytokine interleukin (IL)-17A. In conclusion, these data supported the hypothesis that the influence of ITFs on the host's intestinal status is not always beneficial in the context of ABx-induced biological disorder. However, the significance of these findings needs to be determined by advanced studies KEY POINTS: • ITFs did not promote the recovery of microbial community composition. • ITFs delayed the recovery of ABx-induced colonic inflammation. • ITFs reduced the secretion of TGF-β1 and SIgA. • ITFs delayed the recovery of Treg and B cells in the LP.

Changes in Psychological Anxiety and Physiological Stress Hormones in Korea National Shooters.

Psychological anxiety and physiological stress hormone management is closely related to an athlete’s performance, especially in shooting competitions. Thus, we aimed to investigate the changes in saliva stress hormones according to anxiety scores of Korean elite shooters immediately before a shooting competition. Seventy-two Korean national shooting athletes (Rifle = 62, Pistol = 8, Shotgun = 2) were recruited for the present study. The physiological stress hormones were assessed based on cortisol and immunoglobulin A level in saliva. The psychological stress was assessed based on Beck Anxiety Inventory (BAI) questionnaire. Cortisol concentration and cortisol secretion rate were significant higher in severe anxiety group. Secretory immunoglobulin A (SIgA) concentration and SIgA secretion rate did not significant different in among the groups. A positive correlation was found between BAI score and cortisol concentration. These findings provide preliminary evidence indicating that psychological anxiety affects physiological stress and therefore may have a negative effect on athletes’ performance. Thus, research is needed to develop a strategy to reduce physiological stress in these athletes.

Longan Pulp Polysaccharide Protects Systemic Immunity and Intestinal Immunity in Mice Induced by Cyclophosphamide

Abstract Objectives This study aimed to explore the effect of longan pulp polysaccharide (LP) on the systemic immunity and intestinal mucosal immunity with immunosuppressive mice. The synthesis processing and secretion of intestinal secretory IgA (SIgA) were investigated. Methods Serum IgA, IgG, IgM and intestinal SIgA were detected by ELISA. Genes involved in the synthesis and secretion of SIgA were detected by Q-PCR and western blot. Results LP increased the thymus index, spleen index, and serum IgA level in cyclophosphamide (CTX)-treated mice. SIgA secretion in intestinal lumen was increased by LP as well. The underlying mechanism comes down to the facts as follows: LP increased intestinal cytokines expression and TGFβRII that is associated with pathways of IgA class switch recombination (CSR). By improving protein expression of mucosal address in cell-adhesion molecule-1 (MAdCAM-1) and integrin α4β7, LP was beneficial to gut homing of IgA + plasma cells. LP increased IgA, polymeric immunoglobulin receptor (pIgR), and secretory component (SC) to fortify the SIgA secretion. Conclusions This study suggested that moderate consumption of LP is helpful for improving systemic immunity and intestinal mucosal immunity via promotion of intestinal SIgA to strengthen the mucosal barrier. Funding Sources This work was supported by the National Key Research Project of China (2018YFC1602105, 2019YFD1002304), Guangdong Provincial Science and Technology Project (2018A050506050), President Foundation of Guangdong Academy of Agricultural Sciences (201812B).

Effects of GABA Supplementation on Intestinal SIgA Secretion and Gut Microbiota in the Healthy and ETEC-Infected Weanling Piglets.

Pathogenic enterotoxigenic Escherichia coli (ETEC) has been considered a major cause of diarrhea which is a serious public health problem in humans and animals. This study was aimed at examining the effect of γ-aminobutyric acid (GABA) supplementation on intestinal secretory immunoglobulin A (SIgA) secretion and gut microbiota profile in healthy and ETEC-infected weaning piglets. A total of thirty-seven weaning piglets were randomly distributed into two groups fed with the basal diet or supplemented with 40 mg·kg−1 of GABA for three weeks, and some piglets were infected with ETEC at the last week. According to whether ETEC was inoculated or not, the experiment was divided into two stages (referred as CON1 and CON2 and GABA1 and GABA2). The growth performance, organ indices, amino acid levels, and biochemical parameters of serum, intestinal SIgA concentration, gut microbiota composition, and intestinal metabolites were analyzed at the end of each stage. We found that, in both the normal and ETEC-infected piglets, jejunal SIgA secretion and expression of some cytokines, such as IL-4, IL-13, and IL-17, were increased by GABA supplementation. Meanwhile, we observed that some low-abundance microbes, like Enterococcus and Bacteroidetes, were markedly increased in GABA-supplemented groups. KEGG enrichment analysis revealed that the nitrogen metabolism, sphingolipid signaling pathway, sphingolipid metabolism, and microbial metabolism in diverse environments were enriched in the GABA1 group. Further analysis revealed that alterations in microbial metabolism were closely correlated to changes in the abundances of Enterococcus and Bacteroidetes. In conclusion, GABA supplementation can enhance intestinal mucosal immunity by promoting jejunal SIgA secretion, which might be related with the T-cell-dependent pathway and altered gut microbiota structure and metabolism.

Active free secretory component and secretory IgA in human milk: do maternal vaccination, allergy, infection, mode of delivery, nutrition and active lifestyle change their concentrations?

Free secretory component (free SC) in human milk is a critical constituent of secretory IgA (SIgA) for immune exclusion, but its concentration in human milk is unknown. To evaluate the relationship between free SC and SIgA, the influence of maternal factors (vaccination during pregnancy, allergy, previous infections, nutrition, mode of delivery and active lifestyle) on the concentrations of those secretory immune components in human milk was investigated. Concentration of active free SC and SIgA in 124 milk samples from 91 mothers were measured via ELISA. Free SC in milk from Tdap-vaccinated mothers was lower than the Tdap-flu-vaccinated, flu-vaccinated or Rhogam-vaccinated mothers. Free SC in mothers who had a cesarean delivery was higher than mothers who had a vaginal delivery. Free SC in the nonallergic group was higher than the allergic group. Free SC was higher in mothers who rarely/never eat junk food, than in mothers who always/frequently eat junk food. Free SC also was higher in the moderate exercise group (active lifestyle) compared with the group who rarely/never exercise (sedentary lifestyle). Free SC in human milk was not affected by previous maternal infection or probiotic supplementation whereas SIgA was not changed by all investigated maternal factors. This study suggests that active free SC is more impacted by maternal factors than active SIgA in human milk. Active free secretory component (free SC) is more impacted by maternal factors than active secretory IgA (SIgA) in human milk. Vaccination during pregnancy, allergy, nutrition, type of delivery and active lifestyle affect the secretion of free SC in human milk, but not SIgA secretion. Free SC in human milk is a critical constituent of secretory IgA (SIgA) for immune exclusion against pathogens and its active concentration in milk strongly varies between mothers, partially due to their specific maternal background.

Structural insights into secretory immunoglobulin A and its interaction with a pneumococcal adhesin.

Secretory Immunoglobulin A (SIgA) is the most abundant antibody at the mucosal surface. It possesses two additional subunits besides IgA: the joining chain (J-chain) and secretory component (SC). SC is the ectodomain of the polymeric immunoglobulin receptor (pIgR), which functions to transport IgA to the mucosa. How the J-chain and pIgR/SC facilitate the assembly and secretion of SIgA remains incompletely understood. Furthermore, during the infection of Streptococcus pneumoniae, the pneumococcal adhesin SpsA hijacks pIgR/SC and SIgA to gain entry to human cells and evade host defense. How SpsA targets pIgR/SC and SIgA also remains elusive. Here we report a cryo-electron microscopy structure of the Fc region of IgA1 (Fcα) in complex with the J-chain and SC (Fcα-J-SC), which reveals the organization principle of SIgA. We also present a structure of Fcα-J-SC complexed with SpsA, which uncovers the specific interactions between SpsA and human pIgR/SC. These results advance the molecular understanding of SIgA and shed light on S. pneumoniae pathogenesis.

Intranasal vaccination with Listeria ivanovii as vector of Mycobacterium tuberculosis antigens promotes specific lung-localized cellular and humoral immune responses

We have previously demonstrated that a recombinant Listeria ivanovii (LI) strain expressing the ESAT-6 or Ag85C protein of Mycobacterium tuberculosis (Mtb) as a tuberculosis (TB) vaccine candidates induced antigen-specific cellular immune responses after intravenous immunization of mice. However, whether such recombinant strains could induce desired immune responses in the lung, where TB infection occurs, is not clear. In this paper, C57BL/6 J mice were intranasally vaccinated with attenuated LIΔactAplcB-Rv3875 (Δ refers to gene deletion in the bacterial genome) or LIΔactAplcB-Rv0129c, the two vaccine candidates that utilize LI as an antigen delivery vector. Bacterial load in the target organs, histological changes in the infected organs, the percentage of specific cytokine-secreting T cells in the lung and spleen, IgG levels in the serum and secretory IgA (SIgA) levles in bronchoalveolar lavage (BAL) fluid were determined at specific days post inoculation (dpi). The results showed that both strains were mainly confined to the lung and were eliminated at 10 dpi. The histological damage caused by the infection in the lung was slight and recovered by day 5. Intranasal vaccination of the mice twice at an interval of 4 weeks notably elicited TB antigen-specific CD4+ and CD8+ T cell responses in the lung and SIgA secretion in the pulmonary mucosa, and significantly enhanced the percentage of double-functional CD8+ T cells (IFN-γ+ TNF-α+ CD8+). To our knowledge, this is the first report regarding the used of LI vector vaccines to induce promising lung-localized cellular and humoral immune responses by intranasal vaccination. These data suggest that LI could be a novel and promising live vector to construct an intranasal vaccine against respiratory diseases.

Selenium Deficiency in Chickens Induces Intestinal Mucosal Injury by Affecting the Mucosa Morphology, SIgA Secretion, and GSH-Px Activity.

The small intestine is one of the target organs of dietary selenium (Se) deficiency. Our objective was to investigate the effects of Se deficiency on small intestinal mucosa morphology and function in chickens. In the present study, 1-day (d)-old chickens were fed either a commercial diet with 0.15mg/kg Se (control group) or a Se-deficient diet with 0.016mg/kg Se (Se-group). The average daily weight gain, Se content in the blood, secretory immunoglobulin A (SIgA) secretion, and glutathione peroxidase (GSH-Px) activity in the small intestine in chickens were examined after 10, 20, 30, and 40days of feeding. We also observed the morphology of the small intestine and recorded the number of intraepithelial lymphocytes (IELs). The average daily weight gain decreased; the level of Se in the blood decreased significantly; and SIgA secretion and GSH-Px activity in the duodenum, jejunum, and ileum decreased to different degrees. Histological analysis showed that the villus length, crypt depth, mucosal thickness, and number of IELs in the small intestine decreased to different extents in different periods. In the Se-group, longer feeding times were associated with more severe injury to physiological structure and function in the intestinal mucosa in chickens. In conclusion, Se deficiency induced injury of the mucosal immune barrier and physical barrier of the small intestine, and decreased the growth performance and antioxidant capacity in chickens.

Arginine accelerates intestinal health through cytokines and intestinal microbiota

Arginine supplementation improves intestinal damage and intestinal immunity, but the underlying mechanism of the effects of arginine supplementation on intestinal SIgA secretion is largely unknown. Therefore, this study was conducted to investigate the underlying pathway on the effects of arginine supplementation in secretory IgA (SIgA) production in mice. The results showed that 0.4% arginine supplementation promoted (P < 0.05) SIgA production in intestinal lumina and IgA+ plasma cell numbers in the ileum of mouse. Arginine supplementation significantly increased (P < 0.05) cytokines expression in mouse ileal associated with T cell-dependent and T cell-independent pathways of SIgA induction, including IL-5, IL-6, IL-13, transforming growth factor (TGF-)β2, TGF-β3, TGF-βR2, a proliferation-inducing ligand (APRIL), B cell-activating factor (BAFF), vasoactive intestinal peptide (VIP) receptor, and retinal dehydrogenases. Further study showed that 0.4% arginine supplementation markly decreased (P < 0.05) bacterial loads in mouse mesenteric lymph nodes and increased bacterial invasion into the mouse ileal wall, while supplementation of antibiotic abrogated the influence of arginine supplementation on SIgA secretion. Therefore, these data suggest that arginine supplementation might promote SIgA secretion through cytokines and intestinal microbiota might play an important role in SIgA secretion by arginine supplementation in the mouse intestine.

Enrichment of intestinal Lactobacillus by enhanced secretory IgA coating alters glucose homeostasis in P2rx7\u2212/\u2212 mice

The secretory immunoglobulin A (SIgA) in mammalian gut protects the organism from infections and contributes to host physiology by shaping microbiota composition. The mechanisms regulating the adaptive SIgA response towards gut microbes are poorly defined. Deletion of P2rx7, encoding for the ATP-gated ionotropic P2X7 receptor, leads to T follicular helper (Tfh) cells expansion in the Peyer’s patches (PPs) of the small intestine, enhanced germinal centre (GC) reaction and IgA secretion; the resulting alterations of the gut microbiota in turn affects host metabolism. Here, we define gut microbiota modifications that correlate with deregulated SIgA secretion and metabolic alterations in P2rx7−/− mice. In particular, Lactobacillus shows enhanced SIgA coating in P2rx7−/− with respect to wild-type (WT) mice. The abundance of SIgA-coated lactobacilli positively correlates with Tfh cells number and body weight, suggesting Lactobacillus-specific SIgA response conditions host metabolism. Accordingly, oral administration of intestinal Lactobacillus isolates from P2rx7−/− mice to WT animals results in altered glucose homeostasis and fat deposition. Thus, enhanced SIgA production by P2X7 insufficiency promotes Lactobacillus colonization that interferes with systemic metabolic homeostasis. These data indicate that P2X7 receptor-mediated regulation of commensals coating by SIgA is important in tuning the selection of bacterial taxa, which condition host metabolism.

Variation of Salivary IgA During Weight Loss Period Before a Competition Among University Judo Players.

BackgroundThis study aims to investigate the health condition of university judo athletes during a period of weight loss before a competition, using secretory immunoglobulin A (SIgA) in saliva.MethodsThe subjects were 30 university judo athletes, who were divided into three groups: control group (n = 10), under 5% weight loss group (n = 10), and over 5% weight loss group (n = 10). The items evaluated were body weight measurements, salivary SIgA level and its secretion rates, incidences of symptoms of upper respiratory tract infections, and mental state.ResultsThe over 5% body weight loss group had significantly lower SIgA secretion rates on the first day and third day before the real competition compared to those of the control group. Furthermore, the over 5% body weight loss group had an increased number of symptoms of upper respiratory tract infections. Alterations in mental statuses were also seen, such as decreased vitality and increased fatigue on the day before the competition in the over 5% weight loss group.ConclusionsThis study shows that over 5% body weight loss in judo athletes induces a decrease in the salivary SIgA secretion rate and causes health condition of the body and the mind to deteriorate.

Influence of chewing on expression level of human beta-defensin 2 and secretory immunoglobulin A in the epithelium

PurposeThis study aimed to clarify the influence of chewing on human β-defensin 2 (hBD-2) and secretory immunoglobulin A (SIgA) expression levels. MethodsWe included 15 healthy males with no missing teeth (mean age, 25.5±2.5years). Subjects were instructed to chew a piece of gum for 30min. Saliva and skin-extraction samples were collected before and after chewing for 15 and 30min. hBD-2 and SIgA concentrations in the samples were determined using enzyme-linked immunosorbent assay (ELISA). hBD-2 and SIgA expression levels before and after chewing were analyzed using the Mann–Whitney U test, following the Friedman test. The significance level was 0.05. ResultsThe hBD-2 level in skin-extraction samples was significantly different before (99.4±17.3pg/mL) and after chewing for 30min (142±23.0pg/mL). The SIgA level in skin-extraction samples was also significantly different before (2.39±0.25μg/mL) and after chewing for 30min (3.61±0.33μg/mL). No significant difference was noted in either hBD-2 or SIgA secretion rate in saliva between before and after chewing. ConclusionsChewing gum for 30min increased hBD-2 and SIgA expression levels in skin. Moreover, chewing gum could influence the secretion pattern of these two biomolecules on skin, but not in saliva.

IL-17-dependent SIgA-mediated protection against nasal Bordetella pertussis infection by live attenuated BPZE1 vaccine.

BPZE1 is a live attenuated Bordetella pertussis vaccine for nasal administration to mimic the natural route of infection. Here, we studied the mechanism of BPZE1-induced immunity in the murine nasal cavity in contrast to acellular vaccine (aPV), although both vaccines protected against lung colonization. Transfer of splenocytes or serum from BPZE1-vaccinated or aPV-vaccinated mice protected naïve mice against lung colonization but not against nasal colonization. However, transfer of nasal washes from BPZE1-vaccinated mice resulted in protection against nasal colonization, which was lost in IgA-deficient or poly-Ig receptor-deficient mice, indicating that it depends on secretory IgA (SIgA) induction induced in the nose. BPZE1-induced protection against nasal colonization was long-lived despite the relatively rapid decay of SIgA, indicating a potent BPZE1-induced local memory response, likely due to CD4+ tissue-resident memory T cells induced in the nose by BPZE1. These cells produced interleukin-17 (IL-17), known to be important for SIgA secretion. Furthermore, BPZE1 failed to protect Il17-/- mice against nasal colonization by B. pertussis and induced only background levels of nasal SIgA. Thus, our results show important differences in the protective mechanism between the upper and the lower murine respiratory tract and demonstrate an IL-17-dependent SIgA-mediated mechanism of BPZE1-induced protection against B. pertussis nasopharyngeal colonization.

Effects of doe-litter separation on intestinal bacteria, immune response and morphology of suckling rabbits

Gut development is stimulated by exposure to microorganisms, especially early-life microbial exposure. This study aimed to investigate whether doe-litter separation, which is performed in many rabbit farms, affects this exposure and therefore inhibits the development of intestinal system in suckling rabbits. Immediately after parturition, Rex rabbit does (n=16) were adjusted to 8 kits per litter and divided into doe-litter separation (DLS) group and doe-litter together (DLT) group based on the conditions of the does. One healthy kit per litter was selected and sacrificed at 7 d, 14 d, 21 d and 28 d of age, and the number of total bacteria, Escherichia coli and Bacteroides-Prevotella, expression of interleukin 6 (IL-6) and interleukin 10 (IL-10) in duodenum and caecum were investigated by real-time polymerase chain reaction. The morphological parameters of duodenum and vermiform appendix were also measured. Our results showed that doe-litter separation affected the number of intestinal bacteria. At 7 d of age, except for caecal Escherichia coli, the number of the investigated bacteria was decreased by doe-litter separation (P&amp;lt;0.05). But 1 wk later, only the number of total bacteria and Bacteroides-Prevotella in caecal content (P&amp;lt;0.05) and Escherichia coli in duodenal content from DLS kits (P&amp;lt;0.05) were still lower than those from DLT kits. After being provided with supplementary food for 7 d, DLS kits had fewer total bacteria in caecal content (P&amp;lt;0.05) and fewer E. coli in duodenal content (P&amp;lt;0.01) than DLT kits. After growing to 28 d of age, kits in DLS group still tended to have fewer total bacteria in caecal content, and expression of IL-10 and secretion of secretory IgA (sIgA) in vermiform appendix in DLS group was obviously lower than kits in DLT group (P&amp;lt;0.05). The villus height:crypt depth ratio in duodenum at 3&lt;sup&gt;rd&lt;/sup&gt; wk and 4&lt;sup&gt;th&lt;/sup&gt; wk was decreased by DLS (P&amp;lt;0.05). Kits in DLS group had shorter villus height (P&amp;lt;0.05), higher crypt depth (P&amp;lt;0.05) and shorter vermiform appendix (P&amp;lt;0.05) at the end of the trial. Furthermore, separating kits from the doe had a negative effect on their average daily gain at 3&lt;sup&gt;rd&lt;/sup&gt; wk and 4&lt;sup&gt;th&lt;/sup&gt; wk (P&amp;lt;0.05). Limiting the microbiological contact with the mother during suckling period affected the kits’ intestinal flora and could negatively affect the development of intestinal digestive and immune system and growth performance of kits.

High heart rate reactors display greater decreases in tear SIgA concentration following a novel acute stressor

Tear secretory immunoglobulin-A (SIgA) is a putative biomarker of common-cold risk with potential utility in non-invasive diagnostics. As SIgA secretion at the ocular surface is under strong autonomic control, we investigated the relationship between HR reactivity and tear SIgA responses to novel experiential stress. Thirty-two healthy participants undertook a 60 s zip-line ride to evoke acute stress and a seated-rest control trial in a randomised-crossover design. We recorded heart rate (HR) continuously and collected unstimulated tear samples 5 min pre-, 2 min post- and 20 min post-stress/control. Stress increased HR and state anxiety whereas tear SIgA concentration decreased 44% post-stress vs. control. Higher peak HR values during stress uniquely explained 21% of the variance in tear SIgA reactivity to stress (p < 0.01); high HR reactors displayed greater decreases in tear SIgA concentration. We conclude that physiological arousal increases immune reactivity to acute stress and highlight tear SIgA as a minimally-invasive, physiologically relevant biomarker of immune reactivity.

The Effects of a 4-Week, Intensified Training, and Competition Period on Salivary Hormones, Immunoglobulin A, Illness Symptoms, and Mood State in Elite Synchronised Swimmers.

Given the limited research into the physiological and psychological demands of elite synchronised swimming, the aim of this study was to examine 10 elite female synchronised swimmers and analyse the relationship between training load, stress, illness episodes, and salivary biomarkers during a period of training and competition. Saliva samples were collected before (BASE), during an intensified training camp (CAMP), during an international competition period (COMP), and post competition recovery (REC) for analysis of cortisol, testosterone, and secretory immunoglobulin A (SIgA). Illness symptoms, Daily Analysis of Life Demands of Athletes (DALDA), and training load were also monitored. Training load significantly increased from BASE during CAMP and COMP (p < 0.01), and SIgA secretion was higher during COMP compared to BASE and CAMP (p < 0.01). There was no change in salivary testosterone; however, salivary cortisol was elevated during COMP compared to BASE (93%, p < 0.05). DALDA ‘a scores’ were correlated with salivary cortisol (r = 0.429, p = 0.0001). The study demonstrates that a short period of intensified training and competition did not have a detrimental effect on mucosal immunity in elite synchronised swimmers; however, swimmers displayed higher cortisol levels during the competition and increased stress symptoms.