T cells producing the anti-inflammatory cytokine IL-10 regulate allergen-specific Th2 responses in human airways

BACKGROUND

Murine models suggest a critical functional role for the anti-inflammatory cytokine IL-10 in local regulation of allergic airways inflammation. There is little corresponding information on human airway cells. This study aimed to investigate whether local IL-10 production regulates responses by respiratory mucosal leucocytes isolated from nasal polyps.

MATERIALS AND METHODS

Nasal polyp tissue was harvested from 24 patients sensitised to aeroallergens with chronic rhinitis and polyposis undergoing routine polypectomy. Cells were isolated by matrix proteolysis. Cytokine production by polyp cells was determined by cytometric bead array (CBA) and intracellular cytokine analysis. Surface marker expression by polyp cells was determined by flow cytometry.

RESULTS

Allergen stimulation significantly enhanced production of IL-10, but not IL-5 or IFN-γ by nasal polyp cell suspensions. Under the same conditions, neutralisation of IL-10 significantly increased allergen-specific IL-5 and IFN-γ production by nasal polyp cells. Cell depletion experiments showed that T cells themselves were primarily responsible for IL-10 production or for inducing its production by other cells. Intracellular cytokine staining confirmed production of IL-10 in the absence of IL-2 production by T cells in response to allergen.

CONCLUSION

T cells within the human respiratory mucosa produce IL-10, which is capable of inhibiting pro-inflammatory Th2 and Th1 cytokine production in an antigen-specific fashion.

Counter regulation of the high affinity IgE receptor, FcepsilonRI, on human airway dendritic cells by IL-4 and IL-10

BACKGROUND

Immunoglobulin E is a signalling molecule within the environment of the respiratory tract, the high affinity receptor for which, FcepsilonRI, is expressed by dendritic cells (DC). Little is known, however, of the expression and function of FcepsilonRI on DC in the human respiratory tract.

METHODS

CD1c(+) DC were purified from surgically resected nasal turbinates of 11 atopic and 12 nonatopic patients with chronic rhinosinusitis. Expression of FcepsilonRI was determined by flow cytometry. Cytokine production by DC was determined by cytometric bead array.

RESULTS

Expression of FcepsilonRI was significantly elevated on respiratory tract dendritic cells (RTDC) from atopic as compared to nonatopic patients. Activation of RTDC through FcepsilonRI induced production of the pro-inflammatory cytokines IL-6 and TNF-alpha, and the anti-inflammatory cytokine IL-10. The production of IL-6 and TNF-alpha was elevated in atopic compared to nonatopic patients studied. Conversely IL-10 production was elevated in nonatopic patients. Concomitant activation of FcepsilonRI and stimulation of RTDC with IL-4 inhibited production of IL-10 by RTDC. Neutralization experiments with anti-IL-10 Ab enhanced whereas addition of exogenous IL-10 to RTDC inhibited FcepsilonRI-mediated inflammatory cytokine production.

CONCLUSION

The function of FcepsilonRI on RTDC from patients with rhinosinusitis is susceptible to counter regulation by IL-4 and IL-10.

Association between polymorphisms of the GPX1 gene and second primary tumours after index squamous cell cancer of the head and neck

We investigated the association between genetic polymorphisms in GPX1 gene amongst patients who had index squamous cell carcinoma (SCCHN) and a second primary tumour (SPT) after a primary SCCHN in a case-control study. GPX1 genotypes were determined for 61 patients with SPT and for 259 control subjects by a PCR technique using a fluorescent-labelled primer. Analysis was by an ABI automated fluorescent sequencer. The associations between specific genotypes and the development of SPT were examined by logistic regression. A significant difference was found between the control group and the SPT cases in allele frequencies of GPX1 ALA( *)6 and ALA( *)7 (p(trend)=0.04). These results suggest that polymorphisms in the GPX1 gene may be a marker for SPT development and further studies are indicated.

Otological trauma resulting from the Soho Nail Bomb in London, April 1999

We report the otological effects of the April 1999 Soho Nail Bomb on 17 patients. Twenty-one (62%) tympanic membranes were perforated (pars tensa only); 78% closed spontaneously within 6 months. The mean size of the perforation in the tympanic membrane nearer to the blast was significantly larger than the opposite side [33% +/- 8.3 (mean +/- SD) and 13% +/- 4.1 respectively; P = 0.02]. All patients reported hearing losses that were mixed conductive and sensorineural but mainly high-frequency sensorineural (4, 6 and 8 kHz, pure tone average 42.3 dB +/- 20.5). The sensorineural hearing loss correlated inversely with the distance from the explosion but not with the size of perforation. There was no significant difference in the hearing loss between the ear facing the blast and the opposite ear. Fifteen patients (88%) had temporary tinnitus. No patient complained of any vestibular symptoms. The otological effects of a nail bomb in an enclosed space have not been previously reported. Furthermore, an inverse correlation between hearing loss and distance from the explosion and a significant difference in perforation size facing the blast, compared with the opposite side, are also presented for the first time. The high spontaneous closure rate of perforations and minimal ongoing disability from sensorineural losses favour conservative management in most cases.

Validation and clinical application of computer-combined computed tomography and positron emission tomography with 2-[18F]fluoro-2-deoxy-D-glucose head and neck images

BACKGROUND

Positron emission tomography with 2-[18F]fluoro-2-deoxy-D-glucose (PET-FDG) improves the detection of head and neck squamous cell cancer (HNSCC), but lacks anatomical detail. The accuracy of registered computed tomography/magnetic resonance (CT/MR) and PET-FDG in delineation of HNSCC at the primary site and its clinical application was investigated.

METHOD

Preoperatively 30 patients were staged clinically and each had either CT (23), MR (5), or both CT and MR (2) scans, as well as CT/MR-PET-FDG registration. Tumor margins or infiltration of specific anatomical landmarks on the different scans were compared and judged against histology.

RESULTS

For primary tumors CT-PET-FDG (97%) and MR-PET-FDG (100%) delineated the tumor more accurately than CT (69%) or MR (40%) alone. Similarly, CT-PET-FDG (98%) and MR-PET-FDG (100%) were better than CT (70%) and MR alone (80%) in identifying tumor invasion of specific anatomical structures. Management was altered in 7 of 30 patients. The registered images were particularly useful in delineating tumor extension in the infratemporal fossa, maxilla and mandible, and identifying recurrences obscured by scar tissue.

CONCLUSIONS

It is possible to accurately register CT, MR, and PET-FDG data sets in the head and neck. The initial results show that registered CT/ MR-PET-FDG images provide additional clinically relevant information over that obtained from clinical evaluation or conventional CT/MR imaging.

Pet-FDG imaging in the clinical evaluation of head and neck cancer

Images

Bilateral cerebellopontine angle tumors in neurofibromatosis type 2

In a series of over 500 cases of cerebellopontine angle tumors, 19 patients had bilateral neurinomas. Four of these tumors arose from the facial rather than the acoustic nerve. A conservative policy regarding surgery had been adopted in an effort to prevent hearing loss for as long as possible. Nevertheless, all patients operated on in this series are now totally deaf. The results of managing these patients surgically and conservatively are discussed.

Malignant fibrous histiocytoma of the nasopharynx

Malignant Fibrous Histiocytomas (MFH) are uncommon in the head and neck and extremely rare in the nasopharynx. We report a case of MFH arising in the nasopharynx and describe its diagnosis and management. The literature is reviewed and the likely origins of the tumour and its behaviour are discussed.

Water contamination and swimming with the open mastoid cavity

The aim of this study was to assess whether patients with open mastoid cavities should be advised to avoid water contaminating the ear in order to avoid aural discharge. A detailed history and clinical examination was performed on 53 patients with a unilateral modified radical mastoid cavity of more than 5 years duration. The results showed that it is possible to identify reliably the well-designed trouble-free cavity by the features of its skin lining and the ability to visualize the entire cavity through a size 4 Siegle speculum. A patient with this form of cavity very rarely develops aural discharge following water exposure and need not protect the ear during washing but should do so when swimming because of caloric effects.

The prevention of tympanic membrane perforation following the removal of long-term Paparella type II ventilation tubes

Residual perforation following the extrusion or removal of a long-term ventilation tube may occur in between 8.5% and 25% of cases. This prospective clinical trial concerns Paparella II ventilation tubes and demonstrated that (a) extracting (pulling) a tube from the tympanic membrane gives a 6-month perforation rate of 20%, (b) excising (freshening) the edge of the defect at the time of removal decreases the 6-month perforation rate to 3%, and (c) excising the edge significantly accelerates the healing of the tympanic membrane. There was no correlation in this study between the incidence of perforation and age, sex, ear affected, tympanosclerosis, ventilation tube position, tube in situ time or discharge. The study confirmed a high rate of tympanosclerosis (76%) to be associated with ventilation tubes. Long-term discharge (68%) was identified as a problem of Paparella II ventilation tubes.

Pitfalls in the assessment of dysphagia by fibreoptic oesophagogastroscopy

We present a paper to highlight that the investigation of dysphagia by the standard methods of barium swallow and the now routinely used fibreoptic oesophagogastroscope may miss or inadequately assess pharyngeal and hypopharyngeal causes of dysphagia and to remind that if such a cause is suspected then rigid endoscopy is required to assess or exclude the pathology.