The main purpose of this study was to evaluate medication use patterns (i.e., dose escalation, medication adherence, persistence, and switching) of rheumatoid arthritis (RA) patients on etanercept (ETN), infliximab (IFX) or adalimumab (ADA) and the associated healthcare utilization costs using Texas Medicaid data. Study participants were Medicaid beneficiaries (18-63 years) with an RA diagnosis (ICD-9-CM code 714.0x) who had no claim for a biologic agent in the 6-month pre-index period (July 1, 2003 - Dec 31, 2010). The index date was the first date when the patient had the first fill for any of the study TNF inhibitors (ETN, ADA or IFX) within the study identification period (Jan 1, 2004 – Aug 31, 2010). Data were extracted from July 1, 2003 to August 31, 2011. Prescription and medical claims were analyzed over an 18-month study period (i.e., 6-month pre-index and 12-month post-index periods). The primary study outcomes were adherence, persistence, dose escalation, switching and cost (i.e., total healthcare, RA-related and TNF inhibitor therapy cost). The study covariates were demographic factors (age, gender, race/ethnicity), pre-index use of other RA-related medications (pain, glucocorticoids and disease modifying antirheumatic drugs), total number of non-study RA-related medications used at index, pre-index RA and non-RA related visits, pre-index healthcare utilization cost and Charlson Comorbidity Index score. Conditional regression analyses, which accounts for matched samples, were used to address the study objectives. After propensity score matching, 822 patients (n=274/group) comprised the final sample. The mean age (±SD) was 48.9(±9.8) years, and the majority of the subjects were between 45 and 63 years (69.2%), Hispanic (53.7%) and female (88.0%). Compared to patients on ETN, the odds of having a dose escalation were ≈ 5 [Odds Ratio= 4.605 [95% CI= 1.605-12.677], p=0.0031] and ≈ 8 [Odds Ratio=7.520, [95% CI= 2.461-22.983], p=0.0004] times higher for IFX and ADA patients, respectively, while controlling for other variables in the model. Compared to ETN, patients on IFX (p=0.0171) were more adherent while adherence was comparable with patients on ADA (p=0.1144). Compared to patients on ETN, the odds of being adherent (MPR ≥ 80%) to IFX was ≈ 2 times higher [Odds Ratio= 2.437, [95% CI=1.592-3.731], p < 0.0001] while controlling for other variables in the model. Persistence to index TNF inhibitor therapy and likelihood to switch or discontinue index TNF inhibitor therapy were comparable among the 3 study groups. In addition, the duration of medication use (i.e., persistence) prior to switching or discontinuation of index therapy was comparable among the 3 study groups. Furthermore, for each of the cost variables (total healthcare, RA-related and TNF inhibitor therapy cost), costs incurred by patients on ETN were significantly lower (p < 0.01) than those incurred by ADA patients but significantly higher (p < 0.01) than those incurred by IFX patients. Finally, a positive and significant relationship (p < 0.0001) was found between RA-related healthcare cost, adherence and persistence to TNF inhibitor therapies. In conclusion, ETN was associated with lower rates of dose escalation compared to ADA or IFX. However, adherence was better and associated healthcare costs were lower with IFX. Clinicians should endeavor to work with each individual patient to identify patient-specific factors responsible for poor medication use behaviors with TNF-inhibitor therapies. Reducing the impact of these factors and improving adherence should be included as a major part of the treatment plan for each RA patient. RA patients need to be adequately educated on the importance of adhering and persisting to their TNF-inhibitor therapy as poor medication adherence/persistence negatively impacts the RA disease process. / text

TNF is an inflammatory cytokine that plays a critical role in the acute phase response to infection, and its dysregulation has been implicated in the pathology of several inflammatory and autoimmune disorders. TNF gene expression is regulated in a cell type- and inducer-specific manner that involves chromatin alterations at both the TNF promoter and distal DNase I hypersensitive (DH) sites within the TNF/LT locus. While the mechanisms underlying TNF gene activation in monocytes/macrophages and T cells have been studied intensively, the mechanisms of enhanced, repressed, and restored TNF gene expression in the context of classical macrophage activation and endotoxin tolerance remain largely unknown. We set out to understand how TNF gene expression is modulated during these biological processes by characterizing the chromatin environment of the TNF/LT locus.

Σκοπός της παρούσας διατριβής ήταν η μελέτη της ασφάλειας και της αποτελεσματικότητας των αντι-TNFα βιολογικών παραγόντων, ινφλιξιμάβης και αδαλιμουμάβης, στους ασθενείς με ιδιοπαθή φλεγμονώδη νοσήματα του εντέρου (ΙΦΝΕ) στο Πανεπιστημιακό Γενικό Νοσοκομείο Πατρών. Προσπαθήσαμε να εντοπίσουμε τυχόν συσχετίσεις μεταξύ ομάδων ασθενών και εμφάνισης παρενεργειών ή κλινικής ανταπόκρισης. Μέθοδοι: Από τον Μάιο του 2013 ως τον Μάιο του 2014 καταγράφηκαν τα στοιχεία 63 ασθενών με μοναδικά κριτήρια εισαγωγής τη διάγνωσή τους με ΙΦΝΕ (νόσο του Crohn, ελκώδη κολίτιδα ή αδιευκρίνιστη κολίτιδα) και τη θεραπεία τους με ινφλιξιμάβη ή αδαλιμουμάβη. Κριτήριο αποτελεσματικότητας ήταν η κλινική ύφεση ή έξαρση της νόσου. Κριτήριο ασφαλείας ήταν η εμφάνιση ή όχι παρενεργειών. Αποτελέσματα: Το 65,1% των ασθενών (41/63) λάμβανε ινφλιξιμάβη. Μόλις το 20,6% των ασθενών (13/63) απαίτησε τροποποίηση του βιολογικού παράγοντα (αύξηση δόσης ή συχνότητας χορήγησης). Το 11,1% των ασθενών (7/63) διέκοψαν οριστικά τη θεραπεία εξαιτίας μη ανταπόκρισης ή απώλειας ανταπόκρισης και το 3,2% (2/63) εξαιτίας παρενεργειών. Το 7,9% των ασθενών (5/63) αναγκάστηκαν να διακόψουν παροδικά (λιγότερο από 1 έτος) τη θεραπεία λόγω μη ανταπόκρισης ή απώλειας ανταπόκρισης και το 9,5% (6/63) εξαιτίας παρενεργειών. Το 61,1% των ασθενών (33/54) που είχαν λάβει έστω και μια φορά ινφλιξιμάβη και το 38,1% των ασθενών (8/21) που είχαν λάβει έστω και μία φορά αδαλιμουμάβη εμφάνισε παρενέργειες. Οι πιο συχνές παρενέργειες ήταν οι λοιμώξεις (12/59, 20,3%) και οι αρθραλγίες (12/59, 20,3%) στους ασθενείς που λάμβαναν ινφλιξιμάβη, και οι λοιμώξεις (4/10, 40%) και η κεφαλαλγία (4/10, 40%) σε όσους λάμβαναν αδαλιμουμάβη. Το 69,8% των ασθενών (44/63) βρίσκονταν σε ύφεση. Συμπεράσματα: Η δράση των βιολογικών παραγόντων είναι στατιστικά σημαντικά καλύτερη στη νόσο του Crohn παρά στην ελκώδη κολίτιδα (81,4% vs 18,6%, αντίστοιχα βρίσκονταν σε κλινική ύφεση, p < 0,005). Για όσο περισσότερο χρόνο οι ασθενείς λαμβάνουν τους βιολογικούς παράγοντες και όσο νωρίτερα στην πορεία της νόσου τους ξεκινά η λήψη τους, τόσο καλύτερα ανταποκρίνονται. Κανένας θάνατος δεν παρουσιάστηκε. Οι παρενέργειες που αποτέλεσαν αιτία διακοπής (παροδικής ή οριστικής) εμφανίστηκαν μόνο σε ασθενείς που λάμβαναν ινφλιξιμάβη. Η αδαλιμουμάβη φαίνεται να έχει λιγότερες και λιγότερο σοβαρές παρενέργειες. Περαιτέρω μελέτες σε περισσότερους ασθενείς ή σε μεγαλύτερο βάθος χρόνου (περισσότερο από ένα έτος) είναι απαραίτητες για την εξαγωγή πιο ασφαλών συμπερασμάτων. / The aim of this work was to study the safety and efficacy of anti-TNFα biologic agents, infliximab and adalimumab, in patients suffering from inflammatory bowel disorders (IBD) at Patras University Hospital. We tried to associate clinical response or the occurrence of side-effects with several patient groups. Methods: From May 2013 to May 2014, 63 patients were recorded with the only inclusion criteria being their diagnosis with IBD (Crohn’s disease, ulcerative colitis or indeterminate colitis) and the treatment with infliximab or adalimumab. The efficacy was evaluated based on the presence of clinical remission or active disease. The safety was evaluated based on the presence or absence of side-effects. Results: 65.1% of all patients (41/63) received infliximab infusions. Only 20.6% of patients (13/63) required any adjustment to their biologic agent (dose increase or increased dose frequency). 11.1% of patients (7/63) permanently stopped treatment due to lack or loss of response and 3.2% (2/63) due to side-effects. 7.9% of patients (5/63) transiently stopped treatment (up to 1 year) due to lack or loss of response and 9.5% (6/63) due to side-effects. 61.1% of patients (33/54) who had been treated at least once with infliximab presented side-effects. 38.1% of patients (8/21) who had been treated at least once with adalimumab presented side-effects. The most common side-effects recorded in the group of patients that were treated with infliximab were infections (12/59, 20.3%) and arthralgias (12/59, 20.3%). The most common side-effects recorded in the group of patients that were treated with adalimumab were infections (4/10, 40%) and headache (4/10, 40%). 69.8 of patients (44/63) were in clinical remission. Conclusions: The efficacy of biologic agents is statistically significant better in Crohn’s disease than in ulcerative colitis (81.4% Vs 18.6% respectively were in clinical remission, p < 0.005). The longer the patients were being treated with the biologic agents and the sooner these agents were introduced in the course of the disease the better the clinical response was. No death was observed. The side-effects that led to treatment cessation (either permanent or transient) were only associated with the treatment with infliximab. The treatment with adalimumab seems to be associated with both fewer and less serious side-effects. Studies recording more patients and for a longer period of time (more than one year) need to be conducted in order to draw more clear conclusions.

Le muscle squelettique fait preuve d'une remarquable plasticité en réponse aux changements physiologiques, comme l'activité physique, et aux situations pathologiques. Il subit notamment une atrophie sévère lors de la cachexie qui accompagne diverses pathologies chroniques comme le cancer, le SIDA, etc. L'atrophie musculaire est aussi une composante de la sarcopénie qui survient lors du vieillissement normal, et se caractérise par un déclin de la force et de la masse musculaire. L'atrophie musculaire, qui entraîne une augmentation de la mortalité et diminue l'efficacité des traitements, constitue donc un problème de santé majeur.La fonte musculaire se caractérise par une altération de l'équilibre entre synthèse et dégradation protéiques dans les fibres adultes. Des taux particulièrement élevés de cytokines circulantes, dont le TNFα, qui affectent l'homéostasie du muscle via différentes voies de signalisation, semblent être à l'origine de l'atrophie. Les mécanismes de la réponse atrophique musculaire à ces taux circulants élevés sont cependant mal définis. Le TNFα a des effets complexes. Il peut activer de multiples voies de signalisation, parmi lesquelles l'induction de la synthèse de sphingolipides, et plus particulièrement de céramides, par la voie de novo et par l'activation des sphingomyélinases. Au niveau musculaire, les céramides sont connus pour leurs effets sur la signalisation de l'insuline, sur l'apoptose et sur la différenciation myogénique. Par contre, leur implication dans le cadre de l'atrophie n'avait jamais été prise en compte. L'objectif de ce travail a été dans un premier temps de démontrer le rôle des céramides dans l'atrophie. Dans un deuxième temps, nous avons caractérisé la voie de signalisation par laquelle l'augmentation intramusculaire de céramide induite par le TNFα aboutit à une chute de la synthèse protéique, couplée à une augmentation de la protéolyse. Dans ce but, nous avons mis au point des modèles in vitro d'atrophie, impliquant des myotubes traités par des concentrations physiologiques de TNF. Nous avons en parallèle étudié un modèle in vivo de cachexie induite chez la souris par l'implantation d'un adénocarcinome C26. L'analyse des sphingolipides nous a permis de montrer l'augmentation des taux de céramides concomitante à l'atrophie générée in vitro et in vivo. Le rôle des céramides dans l'atrophie a été démontré par l'effet protecteur des inhibiteurs de leur synthèse, dans les modèles in vitro et in vivo. Nous montrons de plus dans un modèle in vitro que les effets atrophiques des céramides sont dus à l'inhibition de la voie de signalisation Phospholipase D/mTOR/Akt. Nos résultats nous ont permis de prouver le rôle des sphingolipides dans le contrôle de l'homéostasie protéique du muscle. La modulation du métabolisme des sphingolipides apparaît donc comme une nouvelle cible thérapeutique prometteuse dans le traitement de la perte musculaire associée à diverses pathologies.

The sphingolipids are a family of membrane lipids with only a structural role, influencing lipid bilayer properties, but they also act as effector molecules with essential roles in many aspects of cell biology. The sphingolipids ceramide, sphingosine and S1P have shown opposite effects: whereas ceramide and sphingosine usually inhibit proliferation and promote apoptotic responses to different stress stimuli, S1P is known to stimulate cell growth, and promote cell survival. Ceramide can be produced through the de novo synthesis pathway, and by membrane sphingomyelin hydrolysis catalyzed by sphingomyelinases. Both pathways can be activated by the pro-inflammatory cytokine TNFa. Because this cytokine has been shown to promote muscle loss and seems to be crucial in the development of cachexia, we hypothesized that the formation of ceramide, or a metabolite, can be involved in tumor-induced muscle wasting. We investigated the role of ceramide in the in vitro atrophic effects of TNFa on differentiated C2C12 myotubes, by using cell permeant ceramides and inhibitors of sphingolipid metabolism. We observed that TNFa atrophic effects, as evaluated by the reduction in myotube area, are mimicked by exogenous ceramides, supporting the idea that ceramide can participate in muscle atrophy. To verify if ceramide is a mediator of TNFa-induced atrophy, and to identify the metabolites potentially involved, we analyzed the effects of drugs able to block sphingolipid metabolism at different steps: the inhibition of de novo synthesis pathway was unable to restore myotube size in the presence of TNFa whereas the inhibitors of neutral sphingomyelinases reversed TNFa-induced atrophy. Moreover, an accumulation of ceramide and sphingosine induced pro-atrophic effects, whereas sphingosine-1-phosphate had a protective effect. These observations establish that in C2C12 myotubes, ceramide or other downstream metabolites such as sphingosine, produced by the neutral sphingomyelinase pathway in response to TNFa stimulation, participate in cell atrophy. To evaluate the in vivo role of sphingolipids, we treated BalbC mice carrying C26 adenocarcinoma woth Myriocin, an inhibitor of the de novo pathway of ceramide synthesis, that is able to deplete muscle tissue in all sphingolipids, was administered daily to the animals. This treatment partially protected animals against tumor-induced loss of body weight and muscle weight, without affecting the size of tumors. Moreover, myriocin treatment significantly reversed the decrease in myofiber size associated with tumor development, and reduced the expression of atrogenes Foxo3 and Atrogin-1, showing that it was able to protect against muscle atrophy. These results strongly suggest that ceramide, or a downstream sphingolipid metabolite, is involved in tumor-induced muscle atrophy. The sphingolipid pathway thus appears as a new potential target of pharmacological interventions aiming at protecting muscle tissue against atrophy.

Agrin and neuregulin are neurotrophic molecules well known for their roles at synapses in the peripheral and central nervous systems. The expression of these two molecules is not restricted to these sites however, as they are broadly expressed across multiple organ systems. What roles do agrin and neuregulin play within these alternate systems; what is the function of these molecules outside the nervous system? Here I investigate potential roles for agrin and neuregulin in inflammation. Inflammation is an immediate response by innate immune cells, primarily macrophages, to infection and is characterized by the synthesis of pro-inflammatory mediators. The innate immune system possesses multiple redundant mechanisms to locally control inflammation. The neuro-immune axis is one means of control. Often called the cholinergic anti-inflammatory pathway, it acts to regulate local inflammation via nerve-secreted acetylcholine signaling through the homopentameric α7 nicotinic acetylcholine receptors (α7nAChR) present on macrophages. Both agrin and neuregulin have been independently described to share an intricate relationship with acetylcholine receptors (AChR) in the nervous system. Agrin is best known for its role in AChR aggregation at the neuromuscular junction while neuregulin has related roles in AChR transcription, cell survival, communication and differentiation. Based on the common characteristics of synapses in the nervous and immune systems we were curious to see if agrin and neuregulin played analogous roles on macrophages. Here we show that agrin and its receptor dystroglycan are expressed on RAW264.7 macrophages. In addition, agrin treated macrophages demonstrate increased endogenous agrin and α7nAChR expression. By blocking α-dystroglycan (α-DG), a receptor for agrin, with an anti-α-DG antibody we further saw a reduction in agrin expression. We also show that agrin is able to aggregate surface α7nAChRs and transmembrane agrin co-localizes with α7nAChRs therein. Agrin appears to induce approximately a 15-fold increase in anti-inflammatory cytokine IL-10 in macrophages but does not increase pro-inflammatory cytokine TNF-α or IL-6 synthesis. Agrin-treated macrophages challenged with LPS, a potent activator of inflammation, exhibit a 57% decrease in IL-6. Macrophages treated with agrin also exhibit a 4-fold increase in STAT3, a regulator of anti-inflammatory action. The potential anti-inflammatory effects of agrin in the periphery parallel previous work describing the effects of neuregulin in the brain. Previous work completed by our lab suggests a role for neuregulin in augmenting the expression of α7nAChRs on microglia, the macrophages of the brain, but not in peripheral macrophages. Here we show that treatment of LPS challenged microglia with neuregulin produces an 88% decrease in IL-6 and a 33% decrease in TNF-α. These results indicate both agrin and neuregulin are able to induce an increase in α7nAChRs and augment the synthesis of pro- and anti-inflammatory cytokines in their respective systems. These results also further the support the evidence of neuro-immune crosstalk in the immune system. Taken together these results present two novel players in inflammatory regulation by macrophages in the periphery and CNS.

The interactions between the immune and nervous systems play an important role in immune and inflammatory conditions. Substance P (SP), the unidecapeptide RPKPQQFFGLM-NH2, is known to upregulate the production of pro-inflammatory cytokines such as tumor necrosis factor (TNF)-α. We report here that 5 (Acetylamino) 4 oxo-6-phenyl-2-hexenoic acid methyl ester (AOPHA-Me) and 4 phenyl 3 butenoic acid (PBA), two anti-inflammatory compounds developed in our laboratory, reduce SP stimulated TNF-α expression in RAW 264.7 macrophages. We also show that AOPHA Me and PBA both inhibit SP stimulated phosphorylation of JNK and p38 MAPK. Furthermore, molecular modeling studies indicate that both AOPHA Me and PBA dock at the ATP binding site of apoptosis signal regulating kinase 1 (ASK1) with predicted docking energies of -7.0 kcal/mol and 5.9 kcal/mol, respectively; this binding overlaps with that of staurosporine, a known inhibitor of ASK1. Taken together, these findings support the conclusion that AOPHA Me and PBA inhibition of TNF-α expression in SP-stimulated RAW 264.7 macrophages is a consequence of the inhibition JNK and p38 MAPK phosphorylation. We have previously shown that AOPHA-Me and PBA inhibit the amidative bioactivation of SP, which also would be expected to decrease formation of pro-inflammatory cytokines. It is conceivable that this dual action of inhibiting amidation and MAPK phosphorylation may be of some advantage in enhancing the anti-inflammatory activity of a therapeutic molecule. We also encapsulated AOPHA-Me separately in polyketal and poly(lactic co glycolic acid) microparticles. The in-vitro release profiles of AOPHA-Me from these particles were characterized. We have also shown that AOPHA-Me, when encapsulated in PCADK microparticles, is an effective treatment for edema induced by adjuvant arthritis in rats. In separate work, it was determined that myo inositol 1,2,3,4,5,6 hexakisphosphate is an inhibitor to early-stage Loblolly pine somatic embryo growth. In addition, it was determined that muco inositol 1,2,3,4,5,6 hexakisphosphate is not an inhibitor to early-stage Loblolly pine somatic embryo growth. These experiments demonstrate the stereochemical dependence of myo inositol 1,2,3,4,5,6 hexakisphosphates inhibitory activity.

Tenocytes are the principal cells of the human Achilles tendon. In tendinosis, changes in the metabolism and morphology of these cells occur. Neurotrophins are growth factors essential for the development of the nervous system. Tumour necrosis factor alpha (TNF-α) has been found to kill sarcomas but has destructive effects in several major diseases. The two systems have interaction effects and are associated with apoptosis, proliferation, and pain signalling in various diseases. Whether these systems are present in the Achilles tendon and in Achilles tendinosis is unknown. The hypothesis is that the tenocytes produce substances belonging to these systems. In Studies I–III, we show that the potent effects of these substances are also likely to occur in the Achilles tendon. We found tenocyte immunoreactions for the neurotrophins brain-derived neurotrophic factor (BDNF), the nerve growth factor (NGF), the neurotrophin receptor p75, and for TNF-α and both of its receptors, TNFR1 and TNFR2. This occurred in both subjects with painful mid-portion Achilles tendinosis, and in controls. Furthermore, we found mRNA expression for BDNF and TNF-α in tenocytes, which proves that these cells produce these substances. TNFR1 mRNA was also detected for the tenocytes, and TNFR1 immunoreactions were upregulated in tendinosis tendons. This might explain why tenocytes in tendinosis undergo apoptosis more often than in normal tendons. Total physical activity (TPA) level and blood concentration of both soluble TNFR1 and BDNF were measured in Study IV. The results showed that the blood concentration of both factors were similar in subjects with tendinosis and in controls. Nevertheless, the TPA level was related to the blood concentration of sTNFR1 in tendinosis, but not in controls. This relationship should be studied further. The findings of this doctoral thesis show that neurotrophin and TNF-α systems are expressed in the Achilles tendon. We believe that the functions include tissue remodelling, proliferation and apoptosis.

Breast cancer is characterized in part by chronic inflammation and tissue remodelling in the mammary gland. Adipocyte enhancer binding protein 1 (AEBP1), a pro-inflammatory protein, is up-regulated in breast cancer and enhances cytokine secretion in the mammary tumour microenvironment. AEBP1 over-expression in cultured macrophages resulted in increased enzymatic activity of MMP-9, a matrix metalloproteinase implicated in processing cytokines and stimulating tumour cell growth and mobility. MMP-9 activates the cytokine tumour necrosis factor-alpha (TNF?), and is required for the transformation of epithelial cells by the cytokine interleukin 6 (IL6). Treatment of epithelial cells with TNF? and IL6, both of which promote tumourigenesis, induced AEBP1 expression. Chromatin immunoprecipitation results suggested AEBP1 induction is directly mediated by pro-inflammatory transcription factors NF-?B and STAT3, downstream effectors of TNF? and IL6, respectively. AEBP1 induction may enhance inflammation, thereby contributing to cell proliferation and survival.

The mammalian immune system has developed diverse strategies to protect the gastrointestinal tract, as this tissue locale represents a huge absorptive surface and is susceptible to microbial breach. Paradoxically, one key aspect of this protective strategy is the maintenance of selected commensal microorganisms. These commensals serve essential roles in digestion, interfere with pathogenic microbial invasion and stimulate development of the host immune system. Therefore, immune responses which deplete these commensal populations are detrimental to the host. One effective intestinal immune response which selectively promotes the survival of commensals is production of antibodies of the IgA isotype which bind to bacteria without triggering inflammatory cytokines. Proteins of the tumor necrosis factor (TNF) family such as Lymphotoxin and BAFF contribute to the induction of IgA responses. Lymphotoxin is required for generation and organization of most organized lymphoid tissues, where B cell differentiation occurs, while BAFF is necessary for B cell survival and induces B cells to produce IgA. In this thesis, I describe work I have done in examining the roles of the TNF family members Lymphotoxin, BAFF and two related TNF family member cytokines, LIGHT and APRIL, in the regulation of IgA production in mice and in humans. Specifically, LIGHT over-expression drives immense production of IgA, leading to renal deposition of immune complexes in mice. Similar to LIGHT, BAFF over-expression drives increases in IgA production in the intestine, however I have shown that the effects of the BAFF pathway on IgA hyper-production are independent of LIGHT activity. Secondly, examining the phenotype of BAFF-over-expressing mice, I have shown that this phenotype resembles human IgA nephropathy (IgAN) and is dependent on intestinal commensals. Finally, I have described a lymphotoxin-dependent chemokine system in the intestinal lamina propria that could be responsible for organizing cells for the development of IgA responses in this mucosal site.