mRNA for genes associated with antigen presentation are expressed by human middle meatal epithelial cells in culture

Non-Reflex Defense Mechanisms of Upper Airway Mucosa: Possible Clinical Application

The sinonasal mucosa has an essential role in defense mechanisms of the upper respiratory tract. The innate immune system presents the primary defense against noxious microorganisms followed by induction of the adaptive immune mechanisms as a consequence of the presence of pathogens. This well-known activation of adaptive immune system in response to presence of the antigen on mucosal surfaces is now broadly applicated in vaccinology research. Prevention of infectious diseases belongs to substantial challenges in maintaining the population health. Non-invasive, easily applicable mucosal vaccination purposes various research opportunities that could be usable in daily practice. However, the existence of multiple limitations such as rapid clearance of vaccine from nasal mucosa by means of mucociliary transport represents a great challenge in development of safe and efficient vaccines. Here we give an updated view on nasal functions with focus on nasal mucosal immunity and its potential application in vaccination in nearly future.

Influenza A Virus M2 Protein Apical Targeting Is Required for Efficient Virus Replication

The influenza A virus (IAV) M2 protein is a multifunctional protein with critical roles in virion entry, assembly, and budding. M2 is targeted to the apical plasma membrane of polarized epithelial cells, and the interaction of the viral proteins M2, M1, HA, and NA near glycolipid rafts in the apical plasma membrane is hypothesized to coordinate the assembly of infectious virus particles. To determine the role of M2 protein apical targeting in IAV replication, a panel of M2 proteins with basolateral plasma membrane (M2-Baso) or endoplasmic reticulum (M2-ER) targeting sequences was generated. MDCK II cells stably expressing M2-Baso, but not M2-ER, complemented the replication of M2-stop viruses. However, in primary human nasal epithelial cell (hNEC) cultures, viruses encoding M2-Baso and M2-ER replicated to negligible titers compared to those of wild-type virus. M2-Baso replication was negatively correlated with cell polarization. These results demonstrate that M2 apical targeting is essential for IAV replication: targeting M2 to the ER results in a strong, cell type-independent inhibition of virus replication, and targeting M2 to the basolateral membrane has greater effects in hNECs than in MDCK cells.IMPORTANCE Influenza A virus assembly and particle release occur at the apical membrane of polarized epithelial cells. The integral membrane proteins encoded by the virus, HA, NA, and M2, are all targeted to the apical membrane and believed to recruit the other structural proteins to sites of virus assembly. By targeting M2 to the basolateral or endoplasmic reticulum membranes, influenza A virus replication was significantly reduced. Basolateral targeting of M2 reduced the infectious virus titers with minimal effects on virus particle release, while targeting to the endoplasmic reticulum resulted in reduced infectious and total virus particle release. Therefore, altering the expression and the intracellular targeting of M2 has major effects on virus replication.

What is the evidence for genetics in chronic rhinosinusitis?

PURPOSE OF REVIEW

To perform analysis of evidence in current literature on the topic of genetics and chronic rhinosinusitis (CRS), with a particular focus on recent findings in the cystic fibrosis transmembrane regulator (CFTR), genes associated with primary ciliary dyskinesia, and taste receptor T2R38. Other genes that have been found to have association with CRS are also presented and discussed.

RECENT FINDINGS

Recent studies in CFTR and CRS research have investigated possible CFTR-potentiators for treatment of refractory CRS. The T2R38 gene has been shown to be applicable in the clinical setting with a testable phenotype and may have a role in the prognosis and influencing management strategies of CRS patients. Many genes of the immune system have been studied, with genome-wide association studies and candidate-gene approaches identifying new associations that will need replication and further elucidation.

SUMMARY

CRS is a multifactorial disease, with strong evidence of a genetic component in its pathophysiology for some cases. Currently, there are over 70 genes that have been genetically associated with CRS in the past 15 years. Future investigations into genetic causes and predispositions of CRS may allow for improved prognostication and development of disease-prevention strategies as well as novel therapeutic targets.

The M2 protein of live, attenuated influenza vaccine encodes a mutation that reduces replication in human nasal epithelial cells

The influenza A virus components of the live, attenuated influenza vaccine (LAIV) encode the HA and NA gene segments from a circulating virus strain and the remaining gene segments from the cold-adapted master donor virus, A/Ann Arbor/6/1960 (H2N2). The master donor virus imparts at least three phenotypes: temperature-sensitivity (ts), attenuation (att), and cold-adaption (ca). The genetic loci responsible for the att and ts phenotypes of LAIV were mapped to PB1, PB2, and NP by reverse genetics experiments using immortalized cell lines. However, some in vivo studies have demonstrated that the M segment, which acquired an alanine (Ala) to serine (Ser) mutation at M2 position 86 during cold adaption - a mutation found in no other influenza A virus strain - contributes to the att phenotype. Prior studies have shown this region of the M2 cytoplasmic tail to be critical for influenza virus replication. Using reverse genetics, we demonstrate that certain amino acid substitutions at M2 positions 83 and 86 alter the replication of influenza A/Udorn/307/72 (H3N2). Importantly, substitution of a Ser at M2 position 86 reduces A/Udorn/307/72 replication in differentiated primary human nasal epithelial cell (hNECs) cultures, but does not considerably affect replication in MDCK cells. When a Ser was substituted for Ala at M2 86 in LAIV, the virus replicated to higher titers and with faster kinetics in hNEC cultures, implicating this amino acid change as contributing to LAIV attenuation. Increased replication also resulted in increased production of IFN-λ. These data indicate the LAIV associated Ser mutation at M2 position 86 contributes to the att phenotype and is associated with a differential regulation of interferon in LAIV infection.

Evaluation of the innate immune responses to influenza and live-attenuated influenza vaccine infection in primary differentiated human nasal epithelial cells

The host innate immune response to influenza virus is a key determinant of pathogenic outcomes and long-term protective immune responses against subsequent exposures. Here, we present a direct contrast of the host responses in primary differentiated human nasal epithelial cell (hNEC) cultures following infection with either a seasonal H3N2 influenza virus (WT) or the antigenically-matched live-attenuated vaccine (LAIV) strain. Comparison of the transcriptional profiles obtained 24 and 36h post-infection showed that the magnitude of gene expression was greater in LAIV infected relative to that observed in WT infected hNEC cultures. Functional enrichment analysis revealed that the antiviral and inflammatory responses were largely driven by type III IFN induction in both WT and LAIV infected cells. However, the enrichment of biological pathways involved in the recruitment of mononuclear leukocytes, antigen-presenting cells, and T lymphocytes was uniquely observed in LAIV infected cells. These observations were reflective of the host innate immune responses observed in individuals acutely infected with influenza viruses. These findings indicate that cell-intrinsic type III IFN-mediated innate immune responses in the nasal epithelium are not only crucial for viral clearance and attenuation, but may also play an important role in the induction of protective immune responses with live-attenuated vaccines.

Restricted replication of the live attenuated influenza A virus vaccine during infection of primary differentiated human nasal epithelial cells

Live Attenuated Influenza Vaccine (LAIV) strains are associated with cold adapted, temperature sensitive and attenuated phenotypes that have been studied in non-human or immortalized cell cultures as well as in animal models. Using a primary, differentiated human nasal epithelial cell (hNEC) culture system we compared the replication kinetics, levels of cell-associated viral proteins and virus particle release during infection with LAIV or the corresponding wild type (WT) influenza viruses. At both 33 °C and 37 °C, seasonal influenza virus and an antigenically matched LAIV replicated to similar titers in MDCK cells but seasonal influenza virus replicated to higher titers than LAIV in hNEC cultures, suggesting a greater restriction of LAIV replication in hNEC cultures. Despite the disparity in infectious virus production, the supernatants from H1N1 and LAIV infected hNEC cultures had equivalent amounts of viral proteins and hemagglutination titers, suggesting the formation of non-infectious virus particles by LAIV in hNEC cultures.

Sinonasal epithelial wound resealing in an in vitro model: inhibition of wound closure with IL-4 exposure

BACKGROUND

Prolonged healing and persistent inflammation following surgery for rhinosinusitis impacts patient satisfaction and healthcare resources. Cytokines interleukin (IL)-4, IL-5, and IL-13 are important mediators in T-helper 2 (Th2) inflammatory rhinosinusitis. Decreased wound healing has been demonstrated with Th2 cytokine exposure, but this has not been extensively studied in sinonasal epithelium. We hypothesized that in vitro exposure of primary sinonasal epithelial cell cultures to Th2 inflammatory cytokine IL-4 and IL-13 would impair wound resealing and decrease expression of annexin A2 at the wound edge.

METHODS

Following 24-hour exposure to IL-4, IL-5, or IL-13 vs controls, sterile linear mechanical wounds were created in primary sinonasal epithelial cultures (n = 12 wounds per condition). Wounds were followed for 36 hours or until complete closure, and residual wound areas were calculated by image analysis. Group differences in annexin A2 were assessed by immunofluorescence labeling, confocal microscopy, and Western blots.

RESULTS

Significant wound closure differences were identified across cytokine exposure groups (p < 0.001). Mean percentage wound closure at the completion of the 36-hour time course was 98.41% ± 3.43% for control wounds vs 85.02% ± 18.46% for IL-4 exposed wounds. IL-13 did not significantly impair sinonasal epithelial wound resealing in vitro. Annexin A2 protein levels were decreased in IL-4 treated wounds when compared to control wounds (p < 0.01).

CONCLUSION

Th2 cytokine IL-4 decreases sinonasal epithelial wound closure in vitro. Annexin A2 is also diminished with IL-4 exposure. This supports the hypothesis that IL-4 exposure impairs sinonasal epithelial wound healing and may contribute to prolonged healing in Th2 inflammatory rhinosinusitis.

The role of hepatocyte growth factor/c-Met in chronic rhinosinusitis with nasal polyps

BACKGROUND

Hepatocyte growth factor (HGF) is a growth factor thought to attenuate Th2-driven eosinophilic airway inflammatory responses. Increased expression of HGF and its receptor c-Met in nasal polyps suggests a role in disease pathogenesis. The effect of HGF on human sinonasal epithelial cell (SNEC) responses to Th2 inflammatory cytokines in chronic rhinosinusitis with nasal polyps (CRSwNP) has not been explored.

METHODS

SNECs isolated from patients with CRSwNP and control subjects were grown in cell culture at the air-liquid interface. The Th2 cytokine IL-13 was applied for 24 hours in the presence or absence of HGF. Eotaxin-3 and c-Met expression was assessed using real-time PCR, immunohistochemistry, and flow cytometry.

RESULTS

SNECs obtained from both CRSwNP and control subjects showed markedly increased expression of eotaxin-3 after exposure to IL-13. HGF significantly blocked IL-13-induced expression of eotaxin-3 in control SNECs, but not in SNECs derived from CRSwNP subjects.

CONCLUSION

SNECs are active participants in sinonasal mucosal immunity, expressing inflammatory mediators in response to potential pathogens and endogenous cytokines. Although Th2 cytokines can elicit expression of proeosinophilic mediators by SNECs, HGF appears to have a down-regulating effect on this response. In patients with CRSwNP, SNECs are resistant to this attenuation, showing continued IL-13-induced eotaxin-3 expression despite HGF treatment. Abnormalities in the regulation of epithelial cell responses to endogenous cytokines and growth factors may contribute to the persistent eosinophilic inflammatory state in CRSwNP.

Amalgam tattoo: a cause of sinusitis?

Little attention has been paid to the toxicity of silver amalgam fillings, which have been used over the centuries in Dentistry. Amalgam particles may accidentally and/or traumatically be embedded into the submucosal tissue during placement of a restoration and perpetuate in such area. This article presents a case of amalgam tattoo and investigates whether it is related to the patient's repeated episodes of sinusitis. The patient was a 46-year-old woman with a 2 mm diameter radiopaque lesion in the right oral mucosa detected on a panoramic radiograph and presented as a black macula clinically. A complete surgical resection was carried out. The histopathological examination revealed deposits of dark-brownish pigments lining the submucosal tissue with adjacent lymphocytic inflammatory infiltrate and multinucleated giant cells phagocyting pigments. There was a negative staining for both iron and melanin. One year after lesion removal, the patient reported that the sinusitis crises had ceased after repeated episodes for years. It may be speculated that the inflammatory process related to amalgam tattoo seems to lead to a local immune response that causes sinusitis because it enhances the human leukocyte antigen DR (HLA-DR) tissue expression.

Technical advances in rhinologic basic science research

Chronic rhinosinusitis (CRS) is the single most common self-reported chronic health condition in the United States and is estimated to affect 16% of the adult population annually. Despite the prevalence of this disease, there still exists an incomplete understanding of CRS pathophysiology. In this review, the authors highlight technological advances in rhinology: real-time polymerase chain reaction, epithelial cell culture, flow cytometry, genomics/single-nucleotide polymorphism detection, microarrays, and genetic/nongenetic animal models of sinusitis. The purpose of this review is to describe these methodologies and their contributions toward achieving a better understanding of CRS.

Modulation of Immune Response by B7 Family Molecules in Tumor Microenvironments

The importance of co-stimulatory and co-inhibitory molecules has been confirmed on a grand scale; with the identification of new B7 family molecules, possessing both immune activating and inhibiting functions, this family has exploded onto the scene of immune regulation. Nowhere, however, has the role of B7 family members been more apparent than in the fight against cancer. In this review, we will discuss recent data regarding the essential and complex role of B7 family members in regulating the immune response within tumor microenvironment.

Chitin stimulates expression of acidic mammalian chitinase and eotaxin-3 by human sinonasal epithelial cells in vitro

BACKGROUND

Sinonasal epithelial cells participate in host defense by initiating innate immune mechanisms against potential pathogens. Antimicrobial innate mechanisms have been shown to involve Th1-like inflammatory responses. Although epithelial cells can also be induced by Th2 cytokines to express proeosinophilic mediators, no environmental agents have been identified that promote this effect.

METHODS

Human sinonasal epithelial cells from patients with chronic rhinosinusitis with nasal polyps (CRSwNPs) and controls were harvested and grown in primary culture. Cell cultures were exposed to a range of concentrations of chitin for 24 hours, and mRNA for acidic mammalian chitinase (AMCase), eotaxin-3, and thymic stromal-derived lymphopoietin (TSLP) were assessed. Other cultures were exposed to interleukin 4 (IL- 4) alone and in combination with dust-mite antigen (DMA) for 36 hours. Extracted mRNA and cell culture supernatant were analyzed for expression of AMCase and eotaxin-3.

RESULTS

Chitin induced a dose-dependent expression of AMCase and eotaxin-3 mRNA but not TSLP. Patients with recalcitrant CRSwNPs showed lower baseline expression of AMCase when compared with treatment-responsive CRSwNP and less induction of AMCase expression by chitin. DMA did not directly induce expression of AMCase or eotaxin-3. Expression of eotaxin-3 was stimulated by IL-4 and further enhanced with the addition of DMA. Levels of AMCase were not significantly affected by either IL-4 or DMA exposure. In some cases, the combination of IL-4 and DMA was able to induce AMCase expression in cell cultures not producing AMCase at baseline.

CONCLUSION

The abundant biopolymer chitin appears to be recognized by a yet uncharacterized receptor on sinonasal epithelial cells. Chitin stimulates production of AMCase and eotaxin-3, two pro-Th2 effector proteins. This finding suggests the existence of a novel innate immune pathway for local defense against chitin-containing organisms in the sinonasal tract. Dysregulation of this function could precipitate or exacerbate Th2 inflammation, potentially acting as an underlying factor in recalcitrant CRSwNP.

Th2 cytokines associated with chronic rhinosinusitis with polyps down-regulate the antimicrobial immune function of human sinonasal epithelial cells

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNPs) is a disorder characterized by persistent eosinophilic Th2 inflammation and frequent sinonasal microbial colonization. It has been postulated that an abnormal mucosal immune response underlies disease pathogenesis. The relationship between Th2 inflammatory cytokines and the innate immune function of sinonasal epithelial cells (SNECs) has not been explored.

METHODS

Human SNECs (HSNECs) isolated from control subjects and patients with CRS were assessed for expression of antimicrobial innate immune genes and proinflammatory cytokine genes by real-time polymerase chain reaction, ELISA, and flow cytometry. A model of the Th2 inflammatory environment was created by exposure of primary HSNEC to the Th2 cytokine interleukin (IL)-4 or IL-13 for 36 hours, with subsequent assessment of innate immune gene expression.

RESULTS

HSNEC obtained from CRSwNP patients displayed decreased expression of multiple antimicrobial innate immune markers, including toll-like receptor 9, human beta-defensin 2, and surfactant protein A. Baseline expression of these genes by normal and CRS HSNEC in culture is significantly down-regulated after incubation with IL-4 or IL-13.

CONCLUSION

Expression of multiple innate immune genes by HSNEC is reduced in CRSwNP. One mechanism appears to be a direct effect of the leukocyte-derived Th2 cytokines present in the sinonasal mucosa in CRSwNP. Impaired mucosal innate immunity may contribute to microbial colonization and abnormal immune responses associated with CRSwNP.

Innate immunity in the paranasal sinuses: a review of nasal host defenses

BACKGROUND

Chronic rhinosinusitis (CRS) is a common inflammatory disorder of the paranasal sinuses. An abnormal host response to common bacterial or fungal pathogens is thought to be an important factor in the disease process. Host sinonasal epithelium plays an important role in initially recognizing the presence of microbes and responding by increasing production of antimicrobial peptides and cytokines, with recruitment of phagocytes and lymphocytes of the adaptive immune system, to eliminate the infection. Recently, the innate immune system and its complex interplay with the adaptive immune system are increasingly being recognized as important in the pathogenesis of chronic inflammatory diseases such as asthma and CRS.

METHODS

Review of recent findings on innate immunity in the pathogenesis of CRS.

RESULTS

New areas of research into potentially novel therapies for CRS are highlighted in this review, with emphasis on toll-like receptors, antimicrobial peptides (cathelicidins and defensins), and surfactant proteins.

CONCLUSION

This review provides an overview of innate immunity in the sinonasal tract and discusses potential use of innate immune peptides as treatments against fungi, biofilms, and superantigens in CRS.

Chronic rhinosinusitis with nasal polyps is associated with decreased expression of mucosal interleukin 22 receptor

INTRODUCTION

Chronic rhinosinusitis with nasal polyps (CRSwNP) is an inflammatory disorder of the sinonasal mucosa that is frequently associated with microbial colonization. Innate defense mechanisms at the mucosal surface are critical in protecting the host from airborne environmental pathogens. Recent studies of skin and gastrointestinal tract inflammatory diseases have shown that stimulation of the interleukin-22 receptor (IL-22R1) nonspecifically increases innate immune responses. The potential role of IL-22R1 in the pathogenesis of CRSwNP has never been explored.

STUDY DESIGN

Prospective.

METHODS

Nine controls and 19 subjects with CRS were prospectively enrolled prior to undergoing endoscopic sinus surgery. Nasal epithelial cells were cultured from surgically obtained ethmoid mucosa and IL-22R1 protein expression was examined via flow cytometry. RNA was extracted from whole mucosal samples and real-time polymerase chain reaction (PCR) was employed to determine expression of IL22 and IL-22R1. Subjects were followed for at least 6 months postoperative to assess for recurrence or persistence of polyps.

RESULTS

Flow cytometry demonstrated the expression of IL-22R1 protein on the surface of cultured nasal epithelial cells. IL-22R1 mRNA was expressed in 100% of the controls and CRSsNP. However, IL-22R1 was only expressed in 55% of patients with recalcitrant CRSwNP. Additionally, levels of IL22R1 were significantly lower in recalcitrant CRSwNP compared to controls and CRSsNP. IL22 levels did not reach statistical significance.

CONCLUSIONS

In this study, we demonstrate IL-22R1 mRNA and protein expression on nasal epithelial cells. Failure of medical and surgical therapy in CRSwNP is associated with significantly decreased expression of IL-22R1. Further research is needed to determine the potential of IL-22R1 as a therapeutic target in CRSwNP.

Immunoglobulins in nasal secretions of patients with allergic rhinitis and chronic rhinosinusitis

Allergic rhinitis and chronic rhinosinusitis are the most frequently encountered inflammatory reactions of the sinonasal mucosa. Nasal-associated lymphoid tissue has been suggested as an inductive site for humoral and cellular immune responses in the upper respiratory tract. Immunoglobulins are important elements in human adaptive immune responses and deficiencies of serum immunoglobulins may be associated with recurrent or refractory infections. However, the local humoral immune response to offending antigens in the nasal environment has not been well elucidated. To determine the levels of IgA and IgG subclasses antibodies in the nasal secretions of patients with allergic rhinitis and chronic rhinosinusitis, 25 patients with allergic rhinitis and 20 with chronic rhinosinusitis were included and their nasal secretions were collected to measure the levels of secretary IgA (sIgA), total IgA (tIgA), and IgG subclasses antibodies. There was a significant elevation of IgG(3) in the nasal secretions of patients with chronic rhinosinusitis. No difference was noted in the levels of sIgA, tIgA, IgG1, IgG2 and IgG4 among the three groups. The local defense mechanism of nose reacts to microorganisms and pathogenic antigens by inducing the adaptive humoral immune response to increase the amount of immunoglobulins, with IgG3 being the major up-regulated antibody.

A comparison of experimental methods in molecular chronic rhinosinusitis research

BACKGROUND

Research into the molecular pathogenesis of chronic rhinosinusitis (CRS) requires the collection and analysis of sinonasal tissue. Recent gene expression studies have used either surgical tissue specimens or isolated epithelial cell preparations. Here, we compare cultures of nasal epithelial cells, nasal brush biopsy, and whole ethmoid mucosa with respect to expression of innate immune genes.

METHODS

Ethmoid mucosa was collected intraoperatively from 12 CRS and control patients. This tissue either was processed whole for mRNA extraction or was used to generate primary nasal epithelial cell cultures. After 6 weeks, epithelial cells in culture were assessed for multiple innate immune proteins by flow cytometry. In parallel, middle meatal brush biopsy specimens were obtained from the same patients and studied acutely in a similar fashion by flow cytometry. Expression of innate immune genes was determined in whole tissue samples by real-time polymerase chain reaction.

RESULTS

Flow cytometry revealed that brush biopsy specimens contain 75% epithelial cells, whereas primary nasal epithelial cell cultures were pure. Epithelial cells derived from individual subjects expressed very similar levels of innate immune markers whether studied acutely or after 6 weeks in culture. Whole tissue mRNA levels were variable and not correlated to epithelial expression.

CONCLUSION

The choice of experimental methodology can greatly influence the results and interpretation of CRS research. Primary nasal epithelial cells maintain their innate immune receptor expression profile when grown in prolonged culture in vitro. These findings imply that alterations in innate immune gene expression in CRS may be intrinsic to the epithelial cells, even outside of their in vivo microenvironment.

The new B7s: playing a pivotal role in tumor immunity

B7-H1, B7-DC, B7-H2, B7-H3, and B7-H4, all new additions to the B7 family, here termed "the new B7s," are emerging as important tools in directing immune function; each with unique, yet often overlapping functions. Clearly, each B7 molecule has developed its own indispensable niche in the immune system. The expression of both stimulatory and inhibitory B7 molecules seems to play an essential role in regulating the immune response to transformed cells through a variety of mechanisms. As specific niches of B7 family members continue to be dissected, their diagnostic and therapeutic potential becomes ever more apparent. In this review, we will discuss the role of the new B7s in activation and inhibition of antitumor immune responses, their prospects in diagnostics, and also potential and developing immunotherapy protocols.

Sinonasal epithelial cell expression of toll-like receptor 9 is decreased in chronic rhinosinusitis with polyps

BACKGROUND

Innate immune recognition of pathogens by sinonasal epithelial cells may play an important role in the pathogenesis of chronic rhinosinusitis (CRS). Previous studies have indicated that toll-like receptor (TLR) mRNA is present in sinonasal mucosa, and levels of TLR9 expression are decreased in recalcitrant CRS with nasal polyps (CRSwNP). However, the cellular source and function of TLR9 in the sinonasal epithelium is not known. In this study, primary epithelial cell cultures were analyzed from control subjects and CRSwNP patients to determine the presence and function of TLR9 protein.

METHODS

Primary epithelial cell cultures were established from 5 controls and 10 CRSwNP patients undergoing sinus surgery. Flow cytometry was used to confirm purity of epithelial cells and to assess expression of TLR9 protein. Epithelial cells were stimulated with TLR9 agonist, and mRNA was analyzed by real-time PCR for expression of human beta-defensin (HBD) 2 and interleukin (IL)-8.

RESULTS

Flow cytometry showed TLR9 protein in 100% of epithelial cells from controls and CRSwNP patients. The level of expression was 50% lower in CRS patients than in controls. Stimulation of epithelial cells with TLR9 agonist produced a 1.5- to 9-fold increase in HBD-2 and IL-8 mRNA expression.

CONCLUSION

Functional TLR9 protein is expressed by normal and diseased sinonasal epithelial cells. The level of TLR9 expression is decreased in CRSwNP patients, consistent with the previous finding of decreased TLR9 mRNA in whole sinonasal tissue. These findings suggest that impaired innate immune responses to pathogens via TLR9 on sinonasal epithelial cells may represent a critical mechanism in chronic inflammatory sinus disease.

Bibliography. Current world literature. Nose and paranasal sinuses

PURPOSE OF REVIEW

Patients with advanced head and neck cancer are being treated with chemo-radiotherapy, and life is being prolonged, with or without persistent disease, for longer than was previously. Hypercalcaemia may present in patients with advanced or disseminated head and neck cancer, and, as such, these patients may present to a larger variety of clinicians for advice concerning their symptoms and illness. Modes of presentation of hypercalcaemia and treatment strategies are reviewed.

RECENT FINDINGS

There were previously few large series of head and neck cancer patients diagnosed with hypercalcaemia, which may or may not have been related to their cancer being treated. Investigations, by way of blood/serum calcium level, may identify such patients. Patients with cancer-related hypercalcaemia have a poor prognosis, but many may respond temporarily to treatment when offered, with an improvement of their quality of life and death.

SUMMARY

Hypercalcaemia should and must be considered in all patients who have or possibly have a diagnosis of a head and neck cancer and who present unwell with symptoms of fatigue, lethargy and somnolence. Investigation must include serum calcium (corrected for serum albumin binding) and parathyroid hormone level. Patients may be treated by a combination of rehydration and bisulphonate therapy until the serum calcium is reduced to a level below 3 mmol/l. The majority of patients diagnosed with hypercalcaemia due to head and neck malignancy die of their diseases in the short term, but some may enjoy a prolongation of life with reasonable quality if diagnosed and treated aggressively.