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Menachem Rottem

Publications and source records attributed to Menachem Rottem.

13 recordsLinked to original sources

Mast cells, which interact with Escherichia coli, up-regulate genes associated with innate immunity and become less responsive to Fc(epsilon)RI-mediated activation.

Mast cells, which are associated with T helper cell type 2-dependent inflammation, have now been implicated in the innate immune response. To further characterize how mast cells are programmed to respond to infectious organisms, we used expression profiling using DNA microarray analysis of gene expression by human mast cells (huMC) during ingestion of Escherichia coli and examined immunoglobulin E (IgE)-mediated degranulation. Analysis of data revealed that specific groups of genes were modulated, including genes encoding transcription factors, cell signaling molecules, cell cycle regulators, enzymes, cytokines, novel chemokines of the CC family, adhesion molecules, and costimulatory molecules. Enzyme-linked immunosorbent assay analysis confirmed the production of tumor necrosis factor and the chemokines CC chemokine ligand (CCL)-1/I-309, CCL-19/macrophage-inflammatory protein-3beta (MIP-3beta), and CCL-18/MIP-4; flow cytometry confirmed the up-regulation of carcinoembryonic antigen-related cell adhesion molecule 1, the integrin CD49d, and CD80. Coincubation with E. coli down-regulated Fc receptor for IgE I (FcepsilonRI) expression and FcepsilonRI-mediated huMC degranulation. These data are consistent with the concept that bacterial exposure directs mast cell responses toward innate immunity and away from IgE-mediated effects.

Cell Adhesion Molecules↗

Mast cells and autoimmunity.

Mast cells (MCs) are major effector cells in allergic diseases. Recently, it has become evident that the contribution of MCs extends far beyond their accepted role in allergic disease, and that they play a more extensive role in a variety of non-allergic immune processes such as the innate immunity response. These cells have a key role in both the induction and elicitation of several autoimmune conditions. Targeting MC development, maturation or activation may be of value in future prevention and treatment of autoimmune conditions.

Autoimmunity↗

Atopy and asthma in migrants.

Atopy and asthma result from the effects of environmental factors on genetically susceptible persons, and different prevalence rates have been documented worldwide. In developed and industrialized countries a higher prevalence of atopy and asthma is observed as compared with undeveloped and less affluent countries. Migration involves exposure to a new set of pollutants and allergens. In addition, it involves several socioeconomic and cultural issues such as housing conditions, diet and accessibility to medical services, all of which are likely to affect migrants' health. Migration studies provide information on the role of environmental factors in the development of atopy and asthma. Immigration to allergy-prevalent countries causes more allergies and asthma in immigrants as compared to the prevalence of atopy in their countries of origin. The increase in allergy and asthma is usually not related to ethnicity, but in certain populations may play an important role. Studies on migrants support the notion that lifestyle and environmental factors in western industrialized countries facilitate atopy and asthma. The effect is time-dependent. Acquiring allergy is influenced by the age at the time of immigration. Migrants, in general, are more prone to the development of allergies than the local population. Low hygiene prior to immigration does not seem to protect against the development of atopy or asthma. Vaccinations do not affect the development of atopy or asthma in the general population and in migrants. Migrants should be aware of the potential of developing allergies and/or asthma. Strategies for primary prevention in high-risk atopic individuals and secondary prevention guidelines should be developed both for populations in developing countries as well as for immigrants from such countries to atopy-prevalent developed countries.

Asthma↗

[Desloratadine for chronic idiopathic urticaria].

BACKGROUND: Chronic idiopathic urticaria (CIU) is a common and frustrating disorder defined as a regular recurrence of hives for a period of more than 6 weeks, and has a major impact on patients' daily quality of life--H1 receptor antagonists are considered to be particularly effective in reducing pruritus, and are recommended as first-line treatment in patients with CIU. However, the efficacy of the treatment is insufficient. OBJECTIVE: To evaluate the efficacy of desloratadine in CIU in Israeli patients. METHODS: An open label multicenter study in 10 centers in Israel. Upon completion of 3-14 days screening for eligibility, eligible patients were given desloratadine 5 mg for 4 weeks. The DLQI questionnaire and the severity of CIU were assessed at baseline and each week for 28 days. RESULTS: One hundred and four patients aged 19 to 85 years (mean +/- SD 45.6 +/- 15.6) who suffered from moderate CIU, despite previous treatment with anti-histamine agents, were selected and treated with desloratadine 5 mg daily for 28 days. There was significant improvement for dermatologic quality of life in each of 10 parameters and in work productivity, and significant decrease in CIU symptoms and signs including the number and size of hives. In the overall evaluation of treatment 51% of patients reported complete or marked relief and 20% had no relief. Adverse events were reported as mild in 10 patients and moderate to severe in 2 patients who discontinued the study due to headache. CONCLUSION: Desloratadine can be successfully used in the treatment of CIU.

Adult↗

Hospital admission trends for pediatric asthma: results of a 10 year survey in Israel.

BACKGROUND: In the last decade there has been an increase in asthma morbidity. Hospital admission rates for childhood asthma are influenced by the prevalence of asthma and the quality of asthma care. OBJECTIVES: To assess trends in hospital admission and readmission rates for childhood asthma in the Jezreel Valley in Israel in the last decade, and to evaluate the possible effect of changes in asthma treatment on hospitalization for acute asthma during this period. METHODS: All records of pediatric patients from the central hospital in the Jezreel Valley in northeastern Israel over a 10 year period from 1990 through 1999 who were diagnosed as having asthma were thoroughly reviewed and analyzed for admissions, re-admissions, and treatment before and during admissions RESULTS: There were 1584 admissions, 1208 were first-time admissions and 376 were re-admissions. The number of first-time admissions increased significantly over time (P < 0.0001), with a significant decrease in re-admissions (P < 0.005); this finding was more significant in children under the age of 8 years (P < 0.005). The length of hospital stay decreased significantly from 3.3 days to 2.7 days (P < 0.002). Significant changes in the use of medications included an increase in inhalant glucocorticoids and a decrease in the use of sodium cromoglycate and theophylline. Controller medication use was concomitant with a significant decrease in the re-admission rates. CONCLUSIONS: The increase in the admission rate and the decrease in the rate of re-admissions and the length of hospital stay probably reflect the increase in the prevalence of asthma and changes in its treatment, respectively. It is essential that asthma be recognized as a significant cause of morbidity and that controller medications be administered to decrease its severity, morbidity, and resultant hospital admissions.

Adolescent↗

Vaccination and allergy.

PURPOSE OF REVIEW: Vaccines have had a major effect on controlling the spread of infectious diseases, but use of certain vaccines was linked to potential allergic and autoimmune side effects in healthy and often in certain high-risk populations. In this review the authors summarize the current knowledge of such risks. RECENT FINDINGS: Immediate systemic allergic reactions after vaccination with commonly used vaccines are extremely rare. Use of certain vaccines was linked to potential allergic side effects in healthy and often in certain high-risk populations. The authors review the data on the risk associated with important vaccines including influenza, smallpox, pneumococcus, Japanese encephalitis, Bacille Calmette-Guerin, pertussis, and measles, mumps, and rubella. Two main components were identified as a source for allergic reactions in vaccines: gelatin and egg protein. There is growing interest in the potential interactions between infant vaccination and risk for development of atopic disease. In addition, there is concern that genetic risk for atopy influences capacity to respond to vaccination during infancy. There is no evidence that vaccines such as Bacille Calmette-Guerin; pertussis; influenza; measles, mumps, and rubella; or smallpox have an effect on the risk of the development of atopy later in life. Immunotherapy provides an efficacious and safe method for the treatment of allergic conditions by immunomodulation of the immune system. The possibility of vaccination triggering or unmasking autoimmunity in genetically susceptible individuals cannot be ruled out, but for the general population the risk-to-benefit ratio is overwhelmingly in favor of vaccinations. SUMMARY: Childhood vaccination remains an essential part of child health programs and should not be withheld, even from children predisposed to allergy. Vaccinations are safe, but special attention should be taken in high-risk individuals with anaphylactic reactions to foods, and in patients with autoimmune diseases.

Adult↗

Atopic dermatits in infants and children in Israel: clinical presentation, allergies and outcome.

BACKGROUND: Atopic dermatitis is a common disease in infants and children and the incidence appears to be rising. OBJECTIVES: To determine the presentation, allergies, and outcome among Israeli infants and children. METHODS: Children with atopic dermatitis referred to the allergy clinic at a regional pediatric center were evaluated for their medical history and their allergy. The allergic assessment was determined by utilizing skin prick tests and/or serum specific immunoglobulin E concentrations. The children were reexamined again for all parameters at the end of the follow-up period. RESULTS: Forty-six children with atopic dermatitis were studied, 27 males (58.7%) and 19 females (41.3%). A family history of allergy was found in 19 (41.3%). The median age at presentation was 17 months. Of the 46 children 33 (71.7%) revealed an allergy to one or more of the allergens. The most common combination was allergy to food and house-dust mites. The mean follow-up time was 64 months. By the age of 8 years full recovery was seen in 16 patients, half of whom recovered within 3.3 years from the date of presentation. The probability of complete remission was 58%, and for either complete or partial remission 76%. Upon reevaluation at the end of the follow-up period some patients lost their sensitivities, while others, who had been allergic to foods, became sensitive to house-dust mites and/or pollens. CONCLUSIONS: Atopic dermatitis is an allergic problem in the northem region of Israel, as it is in other parts of the world. Food allergy and house-dust mites are major contributors to the evolution of eczema.

Child↗

Characterization of novel stem cell factor responsive human mast cell lines LAD 1 and 2 established from a patient with mast cell sarcoma/leukemia; activation following aggregation of FcepsilonRI or FcgammaRI.

Two novel stem cell factor (SCF) dependent human mast cell lines, designated LAD 1 and 2, were established from bone marrow aspirates from a patient with mast cell sarcoma/leukemia. LAD 1 and 2 cells have the ultrastructural features of human mast cells, and express FcepsilonRI, CD4, 9, 13, 14, 22, 31, 32, 45, 64, 71, 103, 117, 132, CXCR4 (CD184), CCR5 (CD195); and intracytoplasmic histamine, tryptase and chymase. LAD 1 and 2 do not exhibit activating mutations at codon 816 of c-kit. Both LAD 1 and 2 release beta-hexosaminidase following FcepsilonRI or FcgammaRI aggregation. The availability of these cell lines offers an unparalleled circumstance to examine the biology of human mast cells.

Adult↗

Chronic urticaria and autoimmune thyroid disease: is there a link?

Chronic idiopathic urticaria (CIU) is a common and frustrating disorder. A subset of patients with CIU has been classified as autoimmune on the basis of two main findings: association with thyroid autoimmunity and anti-IgE and/or anti-IgE receptor antibodies. There is growing evidence that some cases of CIU are associated with thyroid autoimmunity. Patients with CIU have an increased frequency of Hashimoto thyroiditis with the presence of antibodies to thyroglobulin or a microsomal-derived antigen (peroxidase), even in euthyroid patients. No broad non-specific autoimmunity is present. Antibodies reactive with Fc(epsilon)RI, the high-affinity IgE receptor are found in sera of 10-40% of patients with CIU. A smaller subset of patients with CIU lack anti-Fc(epsilon)RI antibodies and have anti-IgE antibodies that cross-link Fc(epsilon)RIs occupied by IgE. There are a minority of CIU patients that lack such antibodies, but can degranulate basophils by a serum factor that has not yet been determined. Most patients with anti-IgE antibodies have an IgG antibody directed against the 34 kd alpha subunit of the IgE receptor. There are no data to suggest that any of the anti thyroid antibodies is pathogenic in terms of CIU, and most likely these are associated, parallel, autoimmune events. Screening for thyroid autoimmunity and function is advisable in all patients with CIU for the early identification of patients requiring either treatment of underlying thyroid dysfunction or follow-up.

Animals↗

Allergic disease and autoimmune effectors pathways.

Allergy and autoimmunity result from dysregulation of the immune system. Until recently, it was generally accepted that the mechanisms that govern these disease processes are quite disparate; however, new discoveries suggest possible common pathogenetic effector pathways. This review illustrates the concomitant presentation of these conditions and the potential relationship or common mechanism in some cases, by looking at the key elements that regulate the immune response in both allergic and autoimmunite conditions: mast cells, antibodies, T cells, cytokines, and genetic determinants. The parallel appearance of allergic and autoimmune conditions in the some patients may reveal that such aberrations of the immune system have a common pathophysiologic mechanism. Mast cells, which play a key role in allergic reactions, and the wealth of inflammatory mediators they express, make it likely that they have profound effects on many autoimmune processes. Activation of protein kinases by inflammatory cytokines and environmental stresses may contribute to both allergic and autoimmune diseases. The presence of autoantibodies in some allergic conditions suggests an autoimmune basis for these conditions. Because of the central role T cells play in immune reactivity, the T-cell receptor (TCR) loci have long been considered important candidates for common disease susceptibility within the immune system such as asthma, atopy, and autoimmunity. Immunomodulation is the key to a successful treatment of allergic and autoimmune conditions.

Autoimmune Diseases↗

[Allergy and asthma].

Asthma often appears early in life as one of the target organs in the allergic process. Allergic rhinitis and asthma are linked by epidemiologic, histologic, physiologic, and immunopathologic characteristics. Identifying risk factors for sensitization and subsequent development of wheezing has significant implications for the prevention and treatment of asthma. A family history of atopy and early sensitization to house dust mites especially increase the risk, while early exposure to infections may reduce the risk. Inner city children have generally increased risk for asthma compared to children raised in rural areas. In a recent study in Israel inner city asthmatic children were more allergic to both indoor and outdoor allergens than rural asthmatic children. A further study is indicated to examine the prevalence of asthma among allergic children. The allergic part of the evaluation of risk factors in asthmatic patients should be examined. The elimination of the offending trigger or decreased exposure can be very helpful in reducing the symptoms requiring medication and long-term effects of the inflammatory process in asthma.

Animals↗