Role of cellular immunity in the pathogenesis of autoimmune skin diseases

The pathomechanism of most autoimmune skin diseases is still elusive; however, recent clinical and basic research is leading novel insights into the cellular and molecular biological underlying pathways. Several types of infectious skin diseases are infiltrated by significant number of gamma/delta T cells and similar observations have been made in selected immune-mediated skin conditions. In particular, a role for gamma/delta T cells has been suggested in discoid lupus erythematosus, contact dermatitis, herpetiformis dermatitis, necrotizing cutaneous vasculitis, and cutaneous lesions of systemic sclerosis. The pathogenesis of these diseases is different and this may suggest multiple potential functions of this subset of T cells in the immune system of the skin. Furthermore, most T cells infiltrating tissue and organs undergoing fibrosis have the potential to produce high levels of interleukin 4. This is particularly true for the CD8+ or CD4+ CD8+ double positive T-cell subsets. Furthermore, leukocyte recruitment is a key event in immunity and a better understanding of the signals involved in autoimmune diseases constitutes a valuable basis for the development of new strategies, which control leukocyte migration and function under pathological conditions.

Differential diagnosis between usual interstitial pneumonia (UIP) and nonspecific interstitial pneumonia (NSIP) assessed by high-resolution computed tomography (HRCT)

PURPOSE

The aim of this study was to assess the accuracy of high-resolution CT in the differential diagnosis between UIP and NSIP, and the correlations with histological and functional findings.

MATERIALS AND METHODS

Patients underwent thin-collimation spiral CT (1 mm), with 10-mm interval. Pulmonary function was assessed with a pneumotacograph and body plethysmograph connected with a computer for data analysis. Three pathologists, blinded to the clinical and functional data, provided a histological diagnosis based on established criteria reported in the literature. The study group only included patients with a histological diagnosis of either UIP or NSIP.

RESULTS

We achieved a correct diagnosis of NSIP in 86.6% of cases (76.4% sensitivity; 84.6% specificity), whereas UIP was correctly diagnosed in 73.3% of cases (84.6% sensitivity; 76.5% specificity). An 80% agreement was achieved between the HRCT and histological findings in the whole case series (73% sensitivity, 87% specificity, p<0.01).

CONCLUSIONS

The most important finding of our study was that a ground glass appearance equal to or greater than 15% is highly suggestive of NSIP. Therefore, our results could be useful to confirm a suggested diagnosis of NSIP.

Anthracycline-based chemotherapy as primary treatment for intravascular lymphoma

BACKGROUND

Optimal therapeutic management of intravascular lymphoma (IVL) lacks precise guidelines.

PATIENTS AND METHODS

The clinico-pathological features of 38 HIV-negative patients with IVL were reviewed to define efficacy of chemotherapy in these malignancies. Clinical characteristics of 22 patients treated with chemotherapy and of 16 untreated patients were compared in order to understand better the impact and causes of potential patient selection.

RESULTS

Median age was 70 years (range 34-90), with a male/female ratio of 0.9; 23 (61%) patients had Eastern Cooperative Oncology Group performance status (ECOG-PS) > 1; 21 (55%) had systemic symptoms. Cutaneous lesions and anemia were significantly more common among patients treated with chemotherapy; central nervous system (CNS) and renal involvement were significantly more common among untreated patients. Chemotherapy was associated with a response rate of 59% and a 3-year overall survival of 33 +/- 11%. Five of six patients with CNS involvement received chemotherapy: four of them died early; only one patient, treated with adriamycin, cyclophosphamide, vincristine, methotrexate, bleomycin and prednisolone (MACOP-B) followed by high-dose chemotherapy and autologous stem cell transplantation (ASCT), was alive at 19 months. High-dose chemotherapy supported by ASCT was indicated at diagnosis in another patient (43 years of age, stage I), who was alive at 71 months, and at relapse after cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) in two patients who died early after transplantation. PS < or = 1, disease limited to the skin, stage I, and use of chemotherapy were independently associated with better outcome.

CONCLUSIONS

Anthracycline-based chemotherapy is the standard treatment for IVL. However, survival is disappointing, with a relevant impact of diagnostic delay and lethal complications. More intensive combinations, containing drugs with higher CNS bioavailability, are needed in cases with brain involvement, and the role of high-dose chemotherapy supported by ASCT should be further investigated in younger patients with unfavorable features.

Impact of regionalisation of cardiac surgery in Emilia-Romagna, Italy

STUDY OBJECTIVE

Assessment of the impact of the regionalisation of cardiac surgery through the organisational form of a hub&spoke model introduced in the year 2000.

DESIGN

Case mix adjusted before (1998-1999)-after (2000-2002) comparison of: (a) in-hospital and 30 days mortality rates; (b) proportion of patients timely (within one day) referred for surgery from spoke to hub centres; (c) patients' waiting times to surgery.

SETTING

Emilia-Romagna, an Italian region with four million residents.

PATIENTS

16,512 patients aged > or =18 years and referred to cardiac surgery over the period 1998-2002.

MAIN RESULTS

Overall, taking into account differences in case mix across the whole study period, the implementation of the regionalisation policy was associated with a 22% reduction (OR: 0.79, 95%CI: 0.66 to 0.93) in in-hospital mortality rate. The corresponding figure for 30 day mortality was 18% (OR: 0.82: 95%CI: 0.69 to 0.98). The individual centres' volume of cases changed over the study period for all hospitals but two, and the biggest reduction in mortality was seen at the centre with the largest increase in caseload.

CONCLUSIONS

This study provides additional evidence on the benefit of regionalisation of cardiac surgery interventions. The system allowed each centre to reach the minimum caseload required to assure good quality of care. These findings suggest that policies aimed at increasing cooperation rather than competition among health service providers have a positive impact on quality of care. Timely referrals for surgery increased by 21% (95%CI: 1.12 to 1.31), and mean waiting times were reduced by 7.5 average days (95%CI: -10.33 to -4.71).

[Cytofluorimetric evaluation of peripheral blood dendritic cells in patients with Mediterranean Kaposi's sarcoma]

AIM

Kaposi's sarcoma (KS) is a lympho-angioproliferative disorder characterized by angiomatous nodules and plaques that mainly affect the skin. The disease is consistently associated with human herpesvirus-8 (HHV8) and with a state of preexistent immunosuppression. Dendritic cells (DCs) have an instrumental role in the activation and function of both innate and adaptative immune responses. At least 2 distinct subsets have been characterized in peripheral blood based on phenotypic markers: myeloid DCs (CD11c+), associated with Ag uptake, T cell activation and ability to secrete IL-12, and plasmacytoid DCs, high virus-induced IFN-alpha producing cells. Because of the role of both DC subtypes in antiviral and antitumor induced responses, we hypothesized that DCs could be involved in the onset and evolution of KS.

METHODS

Thirty-five patients with mediterranean KS assigned to different clinical stages were compared with 51 healthy control subjects. Peripheral blood DCs were quantified and functionally characterised by flow cytometry directly on whole blood samples. The production of the regulatory cytokines, IL-12 and IL-10, was assessed as intracellular accumulation after incubation with or without lipopolysaccharide (LPS).

RESULTS

Myeloid DCs identified as lineage-/HLA-DR+/CD11c+ cells were significantly lower in KS patients than in controls (0.54+/-0.25 vs 0.69 +/-0.26% of the peripheral blood mononuclear cells; p<0.017). Furthermore, CD11c+ DCs were lower in patients with more diffuse disease. Plasmacytoid DCs, identified as lineage-/HLA-DR+/CD123+ cells, were lower in KS patients (0.23+/-0.19 vs 0.36+/-0.17; p<0.001). DCs from KS patients were more mature, as assessed by expression of the maturation marker CD83, and showed an impaired ability to produce IL-12 upon LPS stimulation, as compared with controls.

CONCLUSION

The numerical and functional alterations of peripheral blood DCs observed in KS patients suggest an involvement of these cells in the onset and evolution of the disease.

Treatment of advanced mycosis fungoides by allogeneic stem-cell transplantation with a nonmyeloablative regimen

SUMMARY

Given the poor prognosis of patients with advanced cutaneous T-cell lymphoma and the high transplant-related mortality associated with conventional allogeneic bone marrow transplantation, we performed nonmyeloablative transplantation of allogeneic stem cells (ASCT) from HLA-identical siblings in three patients with this disease. All patients achieved full donor engraftment, clearance of clonal T cells leading to durable complete remissions but experienced high incidence of infections, which proved fatal in one case. These results suggest that nonmyeloablative ASCT is a novel and potentially curative therapy for patients with advanced T-cell lymphomas who have a histocompatible sibling.

Cytotoxicity of paclitaxel in combination with cisplatin and a new Pt-mercaptopyridine complex

In vitro synergy has been reported for exposure to paclitaxel prior to cis-platin (cis-DDP), whereas the reverse sequence resulted in antagonism. There is no clear evidence for an intracellular origin of the schedule-dependent interaction, but several hypotheses have been proposed, such as effects at the level of DNA crosslinks, or binding to tubulin sites. The purpose of this study was to evaluate the cytotoxicity of these two drugs as single agents, in combination and in sequence, against a human colon adenocarcinoma cell line (LoVo). Moreover, we considered the new Pt-mercaptopyridine complex C/2, was like cis-platin in being able to alter DNA conformation. We have therefore studied the cytotoxic effects after single agent exposure, concomitant exposure (paclitaxel + cis-platin and paclitaxel + C/2) and sequential drugs exposure (paclitaxel-->cis-platin and cis-platin-->paclitaxel or paclitaxel-->C/2 and C/2-->paclitaxel). Our results demonstrate that the most cytotoxic effect is induced by paclitaxel and C/2 exposure both in the case of concomitant cell treatment and sequential exposure paclitaxel-->C/2.

High sensitivity of human epidermal keratinocytes (HaCaT) to topoisomerase inhibitors

In the panorama of the numerous established cell lines, the human keratinocyte line HaCaT has a very interesting feature, having a close similarity in functional competence to normal keratinocytes. This cell line has been used in many studies as a paradigm for epidermal cells and therefore we selected HaCaT as a cell model for investigating the activity of three antitopoisomerase drugs (Camptothecin, Doxorubicin, Ciprofloxacin) on in vitro cell growth. The effect was evaluated both by a 24-h cytotoxicity test and by a 7-day antiproliferation assay, in which the cell viability was assessed by an MTT (3-(4,5-dimethyl-2-thiazolyl) 2,5-diphenil-2-H-tetrazolium bromide) test. DNA topoisomerase I was also partially purified from a nuclear extract of HaCaT cells, the level of topo I catalytic activity was measured by a pBR322 DNA relaxation assay and then the in vitro effect of antitopoisomerase drugs on the target enzyme was also assessed. The results indicated that the in vitro sensitivity of human epidermal HaCaT cells to antitopoisomerase drugs is comparable to that of many human tumour cell lines. HaCaT cells express a high level of topoisomerase I activity that is significantly inhibited by both Camptothecin and Doxorubicin and to a minor degree by Ciprofloxacin. A high correlation between the cell sensitivity to the antitopoisomerase I drug measured by the MTT test and the in vitro direct inhibition of HaCaT topoisomerase I was observed, suggesting that HaCaT cells can represent a very interesting model both for studying cellular pharmacokinetics of antineoplastic drugs on keratinocytes and for predicting possible secondary effects, exerted by these drugs on cutaneous cells, during treatment with chemotherapy.

Human herpesvirus 8 DNA in the skin and blood of patients with Mediterranean Kaposi's sarcoma: clinical correlations

BACKGROUND

Kaposi's sarcoma is a multifocal lympho-angioproliferative disease that appears in elderly subjects of Mediterranean origin (classical form), young Africans and immunodepressed patients (as a result of organ transplantation or AIDS). In 1994, DNA sequences of a new human herpesvirus, called HHV-8, were detected in skin lesions and peripheral blood of patients with AIDS-related Kaposi's sarcoma by confirmational display analysis and polymerase chain reaction.

OBJECTIVE

As HHV-8 in peripheral blood mononuclear cells is detected in about 50% of Mediterranean Kaposi's sarcoma patients and its presence fluctuates in time in the same patient, maybe its detection correlates with the clinical behaviour of the disease.

METHODS

By using routine and nested polymerase chain reaction we evaluated the presence of HHV-8-specific DNA sequences in the skin lesions, perilesional healthy skin and peripheral blood mononuclear cells of a group of 40 HIV-negative patients with Mediterranean Kaposi's sarcoma.

RESULTS

HHV-8 DNA sequences have been found in 40/40 (100%) lesional skin of Mediterranean Kaposi's sarcoma, in 35/40 (85%) perilesional apparently normal skin and in 24/40 (60%) peripheral blood monuclear cell samples. The results of polymerase chain reaction on peripheral blood monuclear cells were positive in 41% of the patients with slowly evolving disease as opposed to 74% of those with rapidly evolving disease, and in 47.6% of the patients with stage I-II disease as opposed to 73.6% of those with stage III-IV.

CONCLUSION

The detection of HHV-8 in peripheral blood monuclear cells seems to correlate with the more aggressive stages and the rapid evolution behaviour of Mediterranean Kaposi's sarcoma.

[Paduan Aristotelianism and the birth of experimental medicine]

Padua University was the place of the scientific revolution not only for astronomy and mechanics with Galilei, but also and most of all for medicine. Here the traditional Aristotelianism created the favourable conditions for the discovery of blood circulation by W. Harvey, because of the strict connection established by Aristotle between medicine and philosophy of nature, the importance attributed to empirical observation, carefully and systematically pursuited, the primacy of the heart among other body organs and the attention payed to the function of various organs. The defect of these conditions was the cause of some Descartes' errors concerning blood circulation, which were avoided by Harvey.

Paraneoplastic pemphigus. A report of two cases associated with chronic B-cell lymphocytic leukaemia

Paraneoplastic pemphigus (PNP) is an autoimmune blistering and erosive mucocutaneous disease associated with neoplasia. Clinical manifestations are polymorphous, and include erythema, bullae, erythema multiforme-like lesions and severe mucous membrane involvement. PNP manifesting as lichenoid dermatitis has recently been observed. We describe two Italian men with fatal PNP featuring typical PNP autoantigens associated with chronic B-cell lymphocytic leukaemia. The first patient presented with an extensive blistering eruption, several erythema multiforme-like lesions and severe mucosal involvement. The second patient presented with a lichenoid dermatitis, then developed bullae, and died with an erythrodermic and exfoliative dermatosis resembling pemphigus foliaceus. Our patients represent two Italian cases of well-documented PNP. In patient 2, the sequence of clinical presentations was unique, and strongly supports the hypothesis of epitope spreading through chronic lichenoid inflammation of the dermo-epidermal junction exposing new self antigens, leading to the humoral response characteristic of PNP.

Clonal CD8 infiltration of the skin in common variable immunodeficiency: a prelymphomatous stage?

Common variable immunodeficiency is a heterogeneous syndrome characterized by hypogammaglobulinemia and recurrent bacterial infections. Patients with this syndrome also have an increased incidence of autoimmune disease and malignancy, most notably lymphoproliferative disorders. The treatment for common variable immunodeficiency is supported by the use of intravenous infusion of immunoglobulins that allows for control of the disease and avoidance of recurrent opportunistic infections. This report describes a young patient having common variable immunodeficiency who presented with a clonal CD8(+) lymphocytic infiltration of the skin clinically manifesting as a widespread papulonodular eruption and resolving with intravenous immunoglobulin therapy. We speculate that such a unique cutaneous presentation may represent a prelymphomatous condition because of the development of an autonomous T-suppressor/cytotoxic cell clone, possibly also responsible for the impaired immunoglobulin production.

Reduction of Walsh-transformed electrocardiograms by double logarithmic coding

This work presents an electrocardiogram ECG data reduction method based on Walsh spectrum double logarithmic quantization. The technique is theoretically justified for a simulated ECG and its practical efficiency confirmed using MIT/BIH arrhythmia database signals. By classifying a "good" compression as one with MSE < or = 0.005 for 1:1 spectral reduction, a normal/abnormal ECG mix returned an 87% success rate for waveforms stored with 8- to 11-bit resolution.

Human herpesvirus-8 infection among heterosexual partners of patients with classical Kaposi's sarcoma

BACKGROUND

DNA sequences of human herpesvirus-8 (HHV8) are found in lesions of Kaposi's sarcoma (KS).

OBJECTIVES

To verify the hypothesis of the sexual transmission of HHV8 infection.

METHODS

We used the immunoperoxidase assay to study the prevalence of serum antibodies to HHV8-related antigens in 27 consorts of patients with classical KS, and in a control group of 25 healthy women.

RESULTS

Forty-four per cent of the study group were positive, compared with 8% of the controls.

CONCLUSIONS

The sexual route may be one of the possible ways of transmission of the HHV8 virus.

Cytophagic histiocytic panniculitis and subcutaneous panniculitis-like T-cell lymphoma: report of 7 cases

BACKGROUND

Cytophagic histiocytic panniculitis (CHP) is a rare subtype of panniculitis that usually follows a fatal course, with a terminal hemophagocytic syndrome. Recent reports on a subset of peripheral T-cell lymphoma named subcutaneous panniculitis-like T-cell lymphoma (SPTL) raised the question about the relationship between these entities.

OBSERVATIONS

We describe 7 patients in the study: 1 with fatal CHP, 4 with SPTL, and 2 with long-term CHP. The 5 patients with fatal CHP and SPTL died of complications of hemophagocytic syndrome, with a disease duration ranging from 8 to 74 months. The other 2 patients were still alive 6 and 41 years after disease onset. Immunohistochemical results proved that 2 of the SPTL cases were type alpha/beta and expressed the cytotoxic/suppressor antigen CD8, while the other 2 were type gamma/delta and were positive for the natural killer-associated antigen CD56. In these 4 cases, molecular biology studies by polymerase chain reaction detected T-cell receptor gamma gene rearrangement, indicating a clonal process. In contrast, in the 2 patients who had long-term CHP, the polymerase chain reaction results failed to disclose clonality. In the subject with fatal CHP, genotypic analysis was not performed.

CONCLUSION

Our observations suggest that CHP and SPTL may span a clinicopathologic spectrum in which there is a natural disease progression from CHP to SPTL.

BCL10 gene mutations rarely occur in lymphoid malignancies

BCL10, a gene involved in apoptosis signalling, has recently been identified through the cloning of chromosomal breakpoints in extranodal (MALT-type) marginal zone lymphomas carrying the t(1;14)(p22;q32) translocation. BCL10 was also found mutated in these cases as well as in other types of lymphoid and solid tumors, suggesting that its inactivation may play an important pathogenetic role; however, this has been questioned by recent studies showing a lack of somatic mutations in human cancers. We report the mutation analysis of exons 1-3 of the BCL10 gene in DNAs from 228 cases of lymphoid malignancies (30 B cell chronic lymphocytic leukemias, 123 B and 45 T non-Hodgkin's lymphomas and 30 multiple myelomas). Somatic mutations were detected in four cases (approximately 2%): one small lymphocytic, one follicular and two diffuse large cell lymphomas. The mutations were all within exon 3 and have not been previously reported. Our data suggest that BCL10 mutations may play only a limited role in the pathogenesis of lymphoid neoplasms.

Photopheresis in cutaneous T-cell lymphoma: five-year experience

BACKGROUND

Cutaneous T-cell lymphoma (CTCL) includes several lymphoproliferative disorders involving mature T-lymphocyte proliferation initially confined to the cutis. These affections, after variable periods, may progress to the blood, limph nodes and visceral organs. Mycosis fungoides (MF) is the most frequent form of CTCL and has an indolent clinical course. The therapy of CTCL depends on the stage of the disease and the patient's general conditions. For advanced cases it includes chemotherapy, retinoids, and interferon-alpha. Since 1987 extracorporeal photochemotherapy (ECP), a novel immunomodulatory approach based on apheresis and photoirradiation of leukocytes, has been successfully introduced for the treatment of advanced CTCL. It can prolong survival of patients with erythrodermic CTCL without significant side effects.

OBJECTIVE

To review our five-year experience with ECP in CTCL.

METHODS

Since June 1994, 33 CTCL patients have been recruited for ECP, using two different regimens: two procedures on two consecutive days at four-week intervals for six months, or at two-week intervals for three months with progressive tapering in the second three-month period for the more severe forms. Six patients received ECP with IFN-alpha. ECP was done using the photopheresis UVAR system and UVAR XTS (Therakos, West Chester, Pa) and always with 8-MOP liquid formulation injected directly into the buffy coat bag. Lymphocytes in peripheral blood were immunophenotypically characterized for each patient and every ECP session.

RESULTS

All patients tolerated ECP well, without significant side effects. Thirty patients are clinically evaluable (at least three ECP cycles). A favourable clinical response was obtained in 80.9% (16/21) of MF patients (complete response 33%, partial response 47.6%) and in 66% (6/9) of patients in the Sézary's syndrome phase (complete response 33.3%, partial response 33.3%). Five of the six patients given IFN-alpha as adjunctive therapy had a PR and one a CR. Four patients are in CR without therapy at follow-ups of 46, 20, 10 and 8 months. There have been no changes in the peripheral lymphocyte immunophenotype during the follow-up. In 19/30 patients the CD95 antigen, correlated with cellular apoptosis, was expressed and was frequently associated with a good clinical response.

CONCLUSIONS

In our experience ECP achieved favourable clinical responses in 73% of patients, in monotherapy or in combination with IFN-alpha, without significant side effects.

Coagulation factor XIII, endothelial damage and systemic sclerosis

In the blood coagulation process, Factor XIII (F XIII) is responsible for the stabilization of the fibrin clot. The hypothesized ability of this blood coagulation factor to affect collagen synthesis and degradation led to its use in the treatment of scleroderma. However, the complex mechanism of action of F XIII remains unclear. The aim of our study was to assess possible effects of F XIII on endothelial damage, regarded as an early pathogenic event in systemic sclerosis (SSc). Thus, we measured plasma levels of von Willebrand factor antigen (vWF:Ag), a marker of endothelial cell injury, in 22 patients with SSc, 9 of whom were treated with F XIII and 13 who do not receive the drug. The plasma concentration of F XIII has also been analyzed. Interestingly, the vWF:Ag plasma levels within the group of SSc patients treated with F XIII were significantly lower than those of untreated SSc individuals (p < 0. 02). On the other hand, the highest mean value of vWF:Ag was found in a subset of untreated subjects having SSc with severe lung involvement, supporting a strict relationship between elevated levels of vWF:Ag and severity of the disease. In contrast, plasma concentration of F XIII resulted normal in all but 3 SSc patients, ruling out a deficiency of this blood coagulation factor as promoting the occurrence of SSc. These preliminary findings seem to support the hypothesis that F XIII may play an improving role on endothelial damage, other than the initially suggested action on collagen metabolism, in SSc.

Unilesional follicular mycosis fungoides

Follicular mycosis fungoides (FMF) is an unusual clinical and histological variant of MF, characterized by selective involvement of hair follicles by atypical lymphocytes. We describe a female patient who had follicular papules located only on the medial aspect of her right thigh. To the best of our knowledge, this patient represents the first reported case of unilesional FMF.

Primary cutaneous B-cell lymphoma with a dermatomal distribution

Primary cutaneous B-cell lymphomas (CBCLs) are indolent lymphoproliferative skin disorders with the only exception of the variant arising on the legs, which is characterized by a more aggressive clinical course. We report a case of CBCL unusual in that it presented with a dermatome-like distribution and showed early peripheral lymph node involvement. The other noteworthy finding is that rearrangement of the bcl-2 gene was detected by polymerase chain reaction in skin tissue samples. The bcl-2 rearrangement, which is usually absent in the classic CBCLs, is likely to play a role in the aggressive clinical behavior of the tumor, although further studies are necessary to confirm it. The hypothesis of a virus causing the dermatomal presentation is intriguing but there is no proof for such speculation at this point.

Lupus erythematosus with antiphospholipid syndrome and erythema multiforme-like lesions

The occurrence of erythema multiforme (EM) in patients with lupus erythematosus (LE) has been described previously as a coincidental association. In contrast, LE with EM-like lesions and a peculiar immunological pattern, including positive rheumatoid factor, antinuclear antibodies and a serum antibody against an extract of human tissues recently recognized as similar to Ro (SSA), constitutes an established entity named Rowell's syndrome. We describe a woman with LE and long-standing widespread vesiculobullous and necrotic haemorrhagic EM-like lesions in combination with Ro (SSA) and scl-70 antibodies and the typical laboratory findings of the antiphospholipid syndrome (APS), namely lupus anticoagulant, anticardiolipin antibodies and prolonged activated partial thromboplastin time. This case could conceivably be consistent with a diagnosis of Rowell's syndrome, if the latter is regarded as a clinicopathological spectrum. However, the coexistence of LE, persistent EM-like disease and incomplete APS may also fulfil the diagnostic criteria for the 'multiple autoimmune syndromes'. We speculate that the laboratory markers of APS play a pivotal part in such an unusual clinical presentation.

Cytokines and adhesion molecules in middle ear cholesteatoma. A role in epithelial growth?

The immune response is thought to play a role in dysregulating epithelial growth in cholesteatoma of the middle ear. Through immunohistochemistry (using 18 monoclonal antibodies) on 10 specimens from human middle ear cholesteatomas, T-helper cells mixed with plasma cells, macrophages and scattered T-suppressor and B cells, have been detected in the perimatrix. Mast cells have also been identified in the perimatrix, usually close to the epithelium. Elements positive for D-related human leukocyte antigens (HLA-DR) were more than half of the immune cells. The endothelium of the perimatrix showed a sharp reactivity to the intercellular adhesion molecule-1 (ICAM1) and to the endothelial derived leukocyte adhesion molecule-1 (ELAM1), which play a role in recluting inflammatory cells and modulating the immune response. The expression of ICAM1 in the basal layer of the matrix indicates the homing of inflammatory reactions at the epithelial-stromal junction of the cholesteatoma. An intense expression of interferon-gamma receptor (IFN gamma R) was found in the basal layers of the cholesteatoma matrix, and overexpression of the epithelial growth factor receptor (EGFR) was found in all layers of the matrix. These data support the hypothesis that the epithelial cells in middle ear cholesteatoma are in an activated state and that their hyperproliferation is mediated through cytokines and adhesion molecules.