M2 macrophages coexist with a Th1-driven profile in periapical cysts.

AIM: To evaluate the participation of both Th1 and Th2 responses in periapical cysts by assessing the presence of M2 macrophages, as well as acute IL-1 ß, TNF-α and IL-6 cytokines. METHODOLOGY: Twenty-four cases of periapical cysts were selected. Immuno-expressions of IL-1 ß, IL-6, TNF-α and CD163 were analysed in the cystic capsules in both superficial and deeper regions. Data were analysed with paired Wilcoxon test and Spearman correlation coefficient (P ≤ 0.05). RESULTS: There was a higher expression of IL-1ß, IL-6, TNF-α and M2 macrophages in the superficial region (P < 0.001) of cystic capsules. All acute cytokines had significant positive correlations amongst them regardless of the cystic capsule region. Regarding CD163, positive correlations occurred only with TNF-α (P = 0.007; r = 0.537) and IL-6 (P = 0.018; r = 0.478) in the superficial regions of the cystic capsule. CONCLUSIONS: M2 macrophages participated actively in the inflammatory response of periapical cysts and correlated with the expression of certain acute Th1-related cytokines. This illustrates the coexistence of an acute and chronic Th2-driven immune response in these lesions. Although M2 macrophages favour the healing process, their presence is not sufficient for periapical cyst regression, once an acute active response has occurred due to an infectious stimuli.

Humoral primary immunodeficiency diseases: clinical overview and chest high-resolution computed tomography (HRCT) features in the adult population.

Humoral primary immunodeficiency diseases (hPIDs) are a heterogeneous group of hereditary disorders resulting in abnormal susceptibility to infections of the sinopulmonary tract. Some of these conditions (e.g., common variable immunodeficiency disorders [CVID]) imply a number of non-infectious thoracic complications such as non-infectious airway disorders, diffuse lung parenchymal diseases, and neoplasms. Chest high-resolution computed tomography (HRCT) is a key imaging tool to characterise and quantify the extent of underlying thoracic involvement, as well as to direct and monitor treatment. The aims of this review are to provide a brief clinical overview of hPIDs and describe the related chest HRCT imaging features in the adult population, with a special focus on CVID and its complications.

Piroxicam and laser phototherapy in the treatment of TMJ arthralgia: a double-blind randomised controlled trial.

This study aimed to evaluate the efficacy of piroxicam associated with low-level laser therapy compared with single therapies in 32 patients presenting temporomandibular joint arthralgia in a random and double-blind research design. The sample, divided into laser + piroxicam, laser + placebo piroxicam and placebo laser + piroxicam groups, was submitted to the treatment with infrared laser (830 nm, 100 mW, 28 s, 100 J cm(-2) ) at 10 temporomandibular joint and muscle points on each side during four sessions concomitant to take one capsule a day of piroxicam 20 mg during 10 days. The treatment was evaluated throughout four sessions and 30 days follow-up through visual analogue scale (VAS), maximum mouth opening and joint and muscle (temporal and masseter) pain on palpation. The results showed that all the study groups had a significant improvement in the VAS scores (P < 0·05), and there were no significant group differences. Piroxicam was effective in the reduction of joint and muscle pain on palpation (P < 0·05) and showed the lowest temporal pain (P = 0·02) at the 30-day follow-up. The combination of low-level laser therapy and piroxicam was not more effective than single therapies in the treatment of temporomandibular joint arthralgia. The use of piroxicam was more effective in the following 30 days.

Shrimp allergy in Italian adults: a multicenter study showing a high prevalence of sensitivity to novel high molecular weight allergens.

BACKGROUND: Shrimp is a frequent cause of food allergy worldwide. Besides tropomyosin, several allergens have been described recently. OBJECTIVE: We investigated which allergens are involved in Italian shrimp-allergic adults. METHODS: Sera from 116 shrimp-allergic patients selected in 14 Italian allergy centers were studied. Skin prick tests with house dust mite (HDM) as well as measurements of IgE to Pen a 1 (shrimp tropomyosin) and whole shrimp extract were performed. All sera underwent shrimp immunoblot analysis, and inhibition experiments using HDM extract as inhibitor were carried out on some Pen a 1-negative sera. RESULTS: Immunoblots showed much variability. IgE reactivity at about 30 kDa (tropomyosin) was found in <50% of cases, and reactivity at about 67 kDa and >90 kDa was frequent. Further reactivities at 14-18, 25, 43-50, about 60 and about 80 kDa were detected. Most subjects had a history of shrimp-induced systemic symptoms irrespective of the relevant allergen protein. IgE to Pen a 1 were detected in sera from 46 (41%) patients. Skin reactivity to HDM was found in 43/61 (70%) Pen 1-negative subjects and inhibition studies showed that pre-adsorption of sera with HDM extract induced a marked weakening of the signal at >67 kDa. CONCLUSIONS: Several allergens other than tropomyosin are involved in shrimp allergy in adult Italian patients. Some hitherto not described high molecular weight allergens seem particularly relevant in this population and their cross-reactivity with HDM allergens makes them novel potential panallergens of invertebrates.

Helper activity for immunoglobulin synthesis of T helper type 1 (Th1) and Th2 human T cell clones: the help of Th1 clones is limited by their cytolytic capacity.

A large number of CD4+ human T helper type 1 (Th1) clones specific for purified protein derivative and of Th2 clones specific for the excretory/secretory antigen of Toxocara canis, derived from the same individuals, were analyzed for both cytotoxic capacity and helper function for immunoglobulin (Ig) synthesis. The great majority of Th1, but only a minority of Th2 clones exhibited cytolytic activity. All Th2 (noncytolytic) clones induced IgM, IgG, IgA, and IgE synthesis by autologous B cells in the presence of the specific antigen, and the degree of response was proportional to the number of Th2 cells added to B cells. Under the same experimental conditions, Th1 (cytolytic) clones provided helper function for IgM, IgG, and IgA, but not IgE, synthesis with a peak response at 1:1 T/B cell ratio. At higher T/B cell ratios, a strong decrease of Ig synthesis was observed. All Th1 clones lysed Epstein-Barr virus transformed autologous B cells pulsed with the specific antigen. The decrease of Ig production at high T/B cell ratios correlated with the lytic activity of Th1 clones against autologous antigen-presenting B cell targets. These data suggest that Th1 differ from Th2 human T cell clones not only for their profile of cytokine secretion, but also for cytolytic potential and mode of help for B cell Ig synthesis.

CD30-mediated signaling promotes the development of human T helper type 2-like T cells.

We have recently shown that CD30, a member of the tumor necrosis factor/nerve growth factor receptor superfamily, is preferentially expressed by human T cell clones producing T helper (Th) type 2 cytokines. We report here that costimulation with an agonistic anti-CD30 monoclonal antibody enhanced antigen (Ag)-induced proliferation and cytokine secretion by established human Th2 and Th0 clones. Moreover, costimulation of peripheral blood mononuclear cells with the same anti-CD30 monoclonal antibody resulted in the preferential development of Ag-specific T cell lines and clones showing a Th2-like profile of cytokine secretion. In contrast, early blockade in bulk culture of CD30 ligand-CD30 interaction shifted the development of Ag-specific T cells towards the opposite (Th1-like) phenotype. Taken together, these data suggest that CD30 triggering of activated Th cells by CD30 ligand-expressing Ag-presenting cells may represent an important costimulatory signaling for the development of Th2-type responses.

Epinephrine autoinjector prescription in food-allergic adults: symptom-based only or allergen-based also? An Italian multi-centre study.

BACKGROUND: Epinephrine is the treatment of choice for acute food-allergic reactions but existing guidelines state that it should be prescribed uniquely to patients who already experienced at least one food-induced anaphylactic episode. OBJECTIVE: We investigated whether in Italy epinephrine auto-injector is prescribed uniquely following the existing guidelines only, or is allergen-informed as well (i.e., based on the potential risk associated with sensitization to certain food allergens), and hence preventive. METHODS: 1110 adult patients (mean age 31 years; M/F 391/719) with food allergy seen at 19 allergy outpatient clinics were studied. Patients with a history of probable anaphylaxis were identified. Subjects were classified as having primary (type 1) and/or secondary (type 2) food allergy and were divided into several subgroups based on the offending allergen/food. Epinephrine prescriptions were recorded and analyzed both as a whole and by sensitizing allergen. RESULTS: Epinephrine was prescribed to 138/1100 (13%) patients with a significant difference between subjects with type-1 and type-2 food allergy (132/522 [25%] vs. 6/629 [1%]; p < 0.001). The epinephrine group included most patients with a history of anaphylaxis (55/62 [89%]) or emergency department visits 106/138 (77%). In some specific subsets, namely fish-, tree nuts-, and lipid trasfer protein (LTP)-allergic patients, epinephrine was prescribed to patients without a history of systemic allergic reactions. CONCLUSIONS: Italian allergy specialists prescribe epinephrine auto-injectors both on the basis of clinical history of severe reactions and on a critical analysis of the hazard associated with the relevant protein allergens, which suggests a good knowledge of allergens as well as acquaintance with the guidelines for prescription of emergency medication.

EpidemAAITO: features of food allergy in Italian adults attending allergy clinics: a multi-centre study.

BACKGROUND: Studies of the prevalence of different types of food allergy in adults are lacking. OBJECTIVE: To define the prevalence of IgE-mediated food allergies in Italian adults attending allergy clinics and to assess possible differences associated with geographical position and/or dietary habits. METHODS: Seventeen allergy outpatient clinics scattered throughout Italy participated to a multi-centre study in 2007. The number of atopic subjects and of food allergic patients along with clinical features were recorded by pre-defined criteria. Patients with unequivocal history of food allergy confirmed by positive skin prick test were included as cases. RESULTS: Twenty five thousand six hundred and one subjects were screened; 12,739 (50%) were atopic, and 1079 (8,5%) had IgE-mediated food allergy. Sixty four percent of patients were females. Overall, the most frequent food allergy was the pollen-food allergy syndrome (55%), which was associated with oral allergy syndrome in 95% of cases and whose frequency decreased southbound. Forty-five percent of patients had a type 1 food allergy, in most cases (72%) caused by fruits and vegetables, and generally associated with a history of systemic symptoms. Type 1 food allergies represented 96% of food allergies in the South. Lipid transfer protein (LTP) accounted for 60% of sensitizations and caused most primary food allergies in all areas. CONCLUSION: Plant-derived foods cause most food allergies in Italian adults. The pollen-food allergy syndrome is the most frequent type of food allergy followed by allergy to LTP whose frequency increases southbound. The pattern of allergy to certain foods is clearly influenced by specific geographic features such as pollen exposure and dietary habits.

Causes of food-induced anaphylaxis in Italian adults: a multi-centre study.

BACKGROUND: Data about food-induced anaphylaxis in Italy are missing. OBJECTIVE: It was the aim of this study to detect the main foods/food allergens causing anaphylaxis in Italy. METHODS: The frequency of anaphylaxis and the relative importance of many offending foods were assessed in 1,110 adult patients with food allergy diagnosed by common criteria at 19 allergy centres scattered throughout Italy from 1 January to 31 December 2007. RESULTS: Fifty-eight of 1,110 (5%) food-allergic patients experienced at least 1 episode of anaphylaxis. On average, they were older than other food-allergic patients (34 vs. 31 years; p < 0.05). The majority of anaphylactic episodes occurred in patients sensitized to lipid transfer protein (LTP; n = 19), followed by shrimp (n = 10), tree nuts (n = 9), legumes other than peanut (n = 4), and seeds (n = 2); peanut, spinach, celery, buckwheat, wheat, avocado, tomato, fish, meat, and Anisakis caused an anaphylactic reaction in single patients. Among LTP-hypersensitive patients, peach caused 13/19 anaphylactic episodes. Shrimp-allergic patients were significantly older than other patients with food-induced anaphylaxis (p < 0.05), whereas patients allergic to LTP experienced their anaphylactic episodes at a younger age (p < 0.001). The frequency of anaphylaxis among patients sensitized to LTP, shrimp or tree nuts did not differ between northern and central/southern Italy. CONCLUSION: LTP is the most important allergen causing food-induced anaphylaxis in Italy, peach being the most frequently offending food. Peanut-induced anaphylaxis seems very uncommon. Geographic and environmental differences both between Italy and other countries and within Italy seem to play a relevant role in the pattern of sensitization to foods.

Ability of HIV to promote a TH1 to TH0 shift and to replicate preferentially in TH2 and TH0 cells.

Both interferon gamma (IFN-gamma) produced by T helper 1 (TH1) lymphocytes and interleukin-4 (IL-4) produced by TH2 lymphocytes were reduced in either bulk circulating mononuclear cells or mitogen-induced CD4+ T cell clones from the peripheral blood of individuals infected with human immunodeficiency virus (HIV). There was a preferential reduction in clones producing IL-4 and IL-5 in the advanced phases of infection. However, enhanced proportions of CD4+ T cell clones producing both TH1-type and TH2-type cytokines (TH0 clones) were generated from either skin-infiltrating T cells that had been activated in vivo or peripheral blood T cells stimulated by antigen in vitro when cells were isolated from HIV-infected individuals. All TH2 and most TH0 clones supported viral replication, although viral replication was not detected in any of the TH1 clones infected in vitro with HIV. These results suggest that HIV (i) does not induce a definite TH1 to TH2 switch, but can favor a shift to the TH0 phenotype in response to recall antigens, and (ii) preferentially replicates in CD4+ T cells producing TH2-type cytokines (TH2 and TH0).

Asthma induced by inhalation of flour in adults with food allergy to wheat.

BACKGROUND: Wheat is one of the major food allergens and it is also an inhalant allergen in workers exposed to flour dusts. Food allergy to wheat in adulthood seems to be rare and has never been reported to be associated with asthma induced by flour inhalation. OBJECTIVE: The study aimed at detecting adults with food allergy to wheat and screening them for the presence of specific bronchial reactivity to inhaled wheat proteins. METHODS: Adults with a history of adverse reactions to ingestion of wheat underwent skin prick test with commercial wheat extract and were assessed for the presence of specific wheat IgE in the sera. Food sensitivity to wheat was confirmed by double-blind, placebo-controlled food challenge (DBPCFC). Specific bronchial reactivity was investigated through a specific bronchial challenge with wheat proteins. RESULTS: In nine patients with evidence of specific IgE response to wheat, a diagnosis of food allergy was made by DBPCFC. Only two subjects had asthma as disease induced by ingestion of wheat. Seven subjects reported a history of respiratory symptoms when exposed to flour dusts. A significant reduction of forced expiratory volume in 1 s (FEV(1)) was detected in these seven patients when a specific bronchial challenge with flour proteins was performed. Only three out of seven subjects with asthma induced by flour could be considered occupationally exposed to flour dusts. CONCLUSION: For the first time, it has been shown that specific bronchial reactivity to wheat proteins can be detected in patients with different disorders associated with food allergy to wheat. The presence of asthma induced by inhaled flour is not strictly related to occupational exposure and it may also occur in subjects not displaying asthma among symptoms induced by wheat ingestion.

Purified protein derivative of Mycobacterium tuberculosis and excretory-secretory antigen(s) of Toxocara canis expand in vitro human T cells with stable and opposite (type 1 T helper or type 2 T helper) profile of cytokine production.

A large series of T cell clones (TCC) specific for purified protein derivative (PPD) of Mycobacterium tuberculosis (total 60) or Toxocara canis excretory/secretory (TES) antigen (total 69) were established from the peripheral blood of two healthy individuals and analyzed for their profile of cytokine production in response to stimulation with either the specific antigen or the polyclonal activator phorbol myristate acetate plus anti-CD3 antibody. Under both these experimental conditions, the great majority of PPD-specific TCC secreted IL-2 and IFN-gamma but not, or limited amounts of, IL-4 and IL-5. In contrast, most TES-specific TCC secreted IL-4 and IL-5 but not, or limited amounts of, IL-2 and IFN-gamma. PPD-specific TCC that failed to secrete IL-4 and IL-5, and TES-specific TCC that failed to secrete IL-2 and IFN-gamma, were found to lack transcripts for IL-4 and IL-5, or for IL-2 and IFN-gamma, respectively. During the course of the study, over a 6-mo period, the functional phenotype of both TES- and PPD-specific TCC was repeatedly assessed and remained constant. These data demonstrate that T cells with stable Th1 or Th2 functional pattern exist not only in mice but also in humans and suggest that in the course of natural immunization certain infectious agents preferentially expand T cell subsets with stable and definite profile of cytokine production.

Defective in vitro production of gamma-interferon and tumor necrosis factor-alpha by circulating T cells from patients with the hyper-immunoglobulin E syndrome.

Circulating T cells from four patients with the hyper-IgE syndrome were found to produce significantly lower concentrations of interferon-gamma (IFN-gamma) in response to stimulation with phytohemagglutinin (PHA) than did T cells from eight age-matched healthy controls, three patients with atopic dermatitis and one patient with chronic granulomatous disease. A clonal analysis revealed that patients with hyper-IgE syndrome had markedly lower proportions of circulating T cells able to produce IFN-gamma and tumor necrosis factor-alpha (TNF-alpha) in comparison with controls. In contrast, the proportions of peripheral blood T cells able to produce IL-4 or IL-2 were not significantly different in patients and controls. All the four patients with hyper-IgE syndrome showed high proportions of circulating CD4+ helper T cells able to induce IgE synthesis in allogeneic B cells, as well. Such an activity for IgE synthesis appeared to be positively correlated with IL-4 production by T cells and inversely related to the ability of the same T cells to produce IFN-gamma. Since IFN-gamma exerts an inhibitory effect on the synthesis of IgE and both IFN-gamma and TNF-alpha play an important role in inflammatory reactions, we suggest that the defective production of IFN-gamma may be responsible for hyperproduction of IgE and the combined defect of IFN-gamma and TNF-alpha may contribute to the undue susceptibility to infections seen in patients with hyper-IgE syndrome.

Pathogenic Fungi Causing Symptoms Similar to Phaeosphaeria Leaf Spot of Maize in Brazil.

This study aimed to identify and characterize the pathogens associated with symptoms similar to Phaeosphaeria leaf spot (PLS) of maize in different environmental conditions in Brazil. During the last decade, PLS became an important disease of maize in Brazil. However, doubt persists about the causal agent. Maize leaves with PLS-like lesions were collected from two locations (Cristalina, Goiás State [GO] and Vila Maria, Rio Grande do Sul State [RS]) in two growing seasons. Fungi associated with leaf lesions were isolated and cultured for taxonomic identification. Pathogenicity tests were carried out and the results indicated that three fungi (a Phyllosticta sp., Phoma sorghina, and a Sporormiella sp.) caused leaf spot similar to PLS on maize. The composition of pathogenic fungi in PLS-like lesions varied depending on locations and growing seasons. The fungi P. sorghina and a Phoma sp. (Plenodomus section) occurred in all environments, but the Sporormiella and Phyllosticta spp. were restricted to GO and RS, respectively. The results support the hypothesis that various pathogens are involved in PLS-like symptoms of maize and environmental conditions may influence the predominance of a specific agent.

Simultaneous expression of thyroid peroxidase and human leukocyte antigen-DR by human thyroid cells: modulation by thyrotropin, thyroid-stimulating antibody, and interferon-gamma.

Major histocompatibility class II molecules human leukocyte antigen-DR (HLA-DR) are abnormally expressed by human thyroid cells (HTC) in autoimmune thyroid glands. The simultaneous expression of HLA-DR and organ-specific autoantigens such as thyroid peroxidase (TPO) by HTC might enable these cells to function as antigen-presenting cells, thus perpetuating the autoimmune process. The aim of the present study was to clarify the interplay of endocrine (TSH) and immune [TSab or interferon-gamma (IFN gamma)] factors on the expression of HLA-DR and TPO in HTC. Thyrocytes were cultured with supernatants of T-cells cloned from the infiltrate of Hashimoto's glands, human recombinant IFN gamma, TSab, or TSH. These factors were added either alone or in different combinations and sequences. HLA-DR and TPO were identified in HTC by a double indirect immunofluorescence technique, using a monoclonal anti-HLA-DR antibody and human serum containing anti-TPO antibody, respectively. IFN gamma, either recombinant or produced by T-cell clones, induced HLA-DR appearance in thyrocytes, whereas TSH or TSab stimulated TPO expression. The appearance of HLA-DR induced by IFN gamma was accompanied by a progressive reduction of TPO despite stimulation by TSH or TSab. This decline reached a nadir after 9-10 days in different primary cultures. During this period, a percentage of cells ranging from 10-40% simultaneously expressed HLA-DR and TPO on their surface and in the cytoplasm. The inhibition of TPO expression and the appearance of HLA-DR induced by IFN gamma were rapidly reverted when TSH or TSab was substituted for interleukin in the culture medium and vice versa. We conclude that 1) the expression of TPO or HLA-DR in thyroid cells is a dynamic phenomenon that is differently influenced by TSH, TSab, and IFN gamma. It is the interplay of these factors in different follicles and during different periods of time that determines the expression of TPO alone, HLA-DR alone, or both molecules together in the same thyroid cell; 2) during exposure to TSH (or TSab) and IFN gamma, TPO and HLA-DR can be expressed simultaneously by thyroid cells for up to 7 days; and 3) the modulation of HLA-DR and TPO by supernatants of T-cells cloned from Hashimoto's glands is reproduced by IFN gamma alone.

Cytolytic T cells with Th1-like cytokine profile predominate in retroorbital lymphocytic infiltrates of Graves' ophthalmopathy.

Lymphocytic infiltration of muscular and connective tissues of the retroorbital (RO) space is a histological hallmark of Graves' ophthalmopathy (GO). We have characterized some phenotypical and functional features of T cells derived from RO infiltrates of four GO patients who were submitted to orbital decompression. Fragments of RO tissue were cultured for 7 days in IL-2-conditioned medium in order to generate T cell lines of in vivo activated T cells. Phenotypical analysis of freshly isolated peripheral blood (PB) lymphocytes both from patients and four healthy controls showed a predominance of CD4+ T cells (CD4/CD8 ratios 1.9:2.5), whereas RO-derived T cell lines displayed almost equal proportions of CD4+ and CD8+ cells (CD4/CD8 ratios 0.9:1.2). RO T cell lines and PB T cells from patients and controls were then cloned using a high-efficiency cloning procedure. The phenotypical and functional features of 153 T cell clones (TCC) derived from RO infiltrates were examined and compared with those of 166 and 236 TCC derived from the PB of patients and controls, respectively. CD4/CD8 ratios ranged from 0.8-1.4 in the series of RO-derived TCC and from 1.9-2.2 in the corresponding series of PB-derived TCC. Assessment of lectin-dependent cytolytic activity showed similar proportions of cytotoxic clones in TCC derived from the PB of patients (37%) and controls (38%); most of the cytolytic TCC was CD8+. In contrast, the proportion of cytolytic RO TCC was markedly higher (106/153 = 69%), including 100% of CD8+ and the majority (59/79 = 75%) of CD4+ clones. When compared to TCC derived from the PB of both patients and controls, RO TCC showed remarkably high proportions of both CD8+ and CD4+ clones with a Th1-like cytokine profile, as documented by their ability to secrete IL-2, IFN-gamma, and tumor necrosis factor-alpha (TNF-alpha), but not IL-4 or IL-5. This study provides evidence that cytolytic T cells with Th1 profile of cytokine production predominate in RO infiltrates of GO, a pattern quite similar to those previously described in thyroid infiltrates of Hashimoto's thyroiditis or Graves' disease. The peculiar cytokine secretion profile of RO T cells may be of importance in the pathogenesis of both the tissue alterations and fibrogenic process observed in GO.

Human Th1 and Th2 cells: functional properties, regulation of development and role in autoimmunity.

Evidence has accumulated suggesting the existence in humans of polarized T helper (Th) cell subsets, coded as Th1 and Th2, with defined cytokine secretion profiles. Immune responses to intracellular bacteria and viruses result in the preferential development of the Th1 cell subset. Th1 cells express cytolytic activity against antigen-presenting cells and provide helper function for IgM, IgG and IgA synthesis only at low T/B cell ratios. In contrast, Th2 cells develop in response to allergens or helminth antigens, provide help for all immunoglobulin classes, including IgE, and lack cytolytic potential. The cytokine milieu in the microenvironment plays a fundamental role in determining the functional phenotype of the subsequent antigen-specific Th1 or Th2 responses. In recent years it has become clear that Th1 and Th2 cells play different roles not only in protection against exogenous offending agents, but also immunopathology. Th2 cells are involved in immunopathology induced by helminths and are responsible for the initiation and maintenance of allergic disorders. Th1 cells seem to be involved in contact dermatitis, acute allograft rejection and organ-specific autoimmunity, such as thyroid autoimmune disorders, diabetes mellitus or multiple sclerosis, whereas less polarized patterns of Th cells are detectable in target organs of patients with rheumatoid arthritis. Sjogren's syndrome or systemic lupus erythematosus.

High potential to tumor necrosis factor alpha (TNF-alpha) production of thyroid infiltrating T lymphocytes in Hashimoto's thyroiditis: a peculiar feature of destructive thyroid autoimmunity.

T lymphocytes present in thyroid infiltrates of 6 patients with Hashimoto's thyroiditis (HT) and of 4 patients with Graves' disease (GD) were analyzed at clonal level and their profiles of mitogen-induced lymphokine secretion were characterized. Production of interleukin-2 (IL-2), interleukin-4 (IL-4), interferon-gamma (IFN-gamma) was measured in culture supernatants of a total number of 332 T cell clones (TCC) from HT, of 269 TCC from GD infiltrates and of 266 control TCC derived from normal lymphoid tissues. No significant difference was found in the ability to produce IL-2 between TCC from HT or GD infiltrates and control TCC. The proportion of HT- or GD-derived TCC able to produce IL-4 was extremely low (4 and 5%, respectively) in comparison with controls (19%). In contrast, the proportion of interferon-gamma (IFN-gamma)-producing (IFN-P) TCC derived from either HT (87%) or GD (80%) infiltrates was much higher (p less than 0.0005) than that found in controls (59%). In addition, most of IFN-P TCC from either HT or GD usually released higher amounts (p less than 0.002) of IFN-gamma than did control clones. No significant difference was found between GD infiltrates and controls in the proportions of TCC able to secrete TNF-alpha (39% and 47%, respectively), whereas the proportion of TNF-alpha-producing (TNF-P) TCC derived from HT (78%) was significantly higher (p less than 0.0001). In addition, most of both CD8 and CD4 TCC from HT released higher amounts of TNF-alpha than did TNF-P clones from controls or GD. These data suggest that T cells present in autoimmune thyroid infiltrates share a number of functions, such as high production of IFN-gamma, but differ with regard to their ability to secrete TNF-alpha, which is peculiar of most T cells present in the thyroid of HT patients.

Some relevant aspects in conducting cataract prevalence studies.

This paper deals with some crucial issues relevant to cataract prevalence studies. The desirable property of comparability for different studies is illustrated and it is brought to light that prevalence studies can be planned in order to find out possible risk factors when designed in accordance with some criteria.

CD8 T-cell clones producing interleukin-5 and interferon-gamma in bronchial mucosa of patients with asthma induced by toluene diisocyanate.

OBJECTIVES: The aims of the present study were to determine whether specific in vivo stimulation of asthmatics sensitized with toluene diisocyanate (TDI) induces the activation of T lymphocytes in bronchial mucosa and to characterize their phenotype and cytokine secretion profile. METHODS: Bronchial biopsies from two subjects with occupational asthma due to TDI were obtained 48 h after an asthmatic reaction induced by an inhalation challenge with TDI and after three months of no exposure to TDI, at the time when the subjects had recovered from their asthma. The fragments of bronchial mucosa were cultured in the presence of interleukin-2 so that the in vivo activated T cells present in the tissue would expand, and T blasts were then cloned under limiting dilution conditions. RESULTS: From the two 48-h specimens, 65 and 63 T-cell clones were obtained. Most of the clones exhibited the CD8 phenotype (82 and 83%). All of the CD8 clones produced interferon-gamma and 44% produced interleukin-5, but only 6% secreted interleukin-4 as well. Three months after the cessation of exposure, growing T cells could not be recovered from bronchial biopsies cultured in interleukin-2. CONCLUSIONS: The results suggest that, in sensitized subjects, exposure to TDI induces the activation of a subset of CD8 lymphocytes producing interferon-gamma and interleukin-5.