Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
Toxicon ; 178: 13-19, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32067999

RESUMO

Accidents by freshwater stingrays are common in northern Brazil, there is no specific therapy for high morbidity and local tissue destruction. The irradiation of venoms and toxins by ionizing radiation has been used to produce appropriate immunogens for the production of antisera. We planned to study the efficacy of stinging mucus irradiation in the production of antisera, with serum neutralization assays of edematogenic activity and quantification of cytokines performed in animal models of immunization with native and irradiated mucus of Paratrygon aiereba, a large freshwater stingray. Antiserum potency and its cross-reactivity with mucus from other freshwater stingrays were detected by ELISA. Immunization models demonstrated the ability to stimulate a strong humoral response with elevated levels of serum IgG detectable by ELISA, and both native and irradiated mucus were immunogenic and capable of recognizing mucus proteins from other freshwater neotropical stingrays. Mucus P. aiereba causes cellular and humoral adaptive immune responses in cells of immunized mice producing antibodies and cytokines such as TNF-α, IL-6 and IL-17. Rabbit antisera immunized with mucus from P. aiereba irradiated at 2 kGy showed a significant reduction of mucus-induced edematogenic activity in mice. Our data suggest that the use of antisera against freshwater stingray mucus show the possibility of specific therapy for these accidents.


Assuntos
Mordeduras e Picadas/imunologia , Elasmobrânquios/fisiologia , Soros Imunes/imunologia , Animais , Brasil , Edema , Ensaio de Imunoadsorção Enzimática , Água Doce , Camundongos , Modelos Teóricos , Muco , Dor , Coelhos , Rajidae
2.
Channels (Austin) ; 13(1): 264-286, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31237176

RESUMO

Calcium entry is central to the functional processes in mast cells and basophils that contribute to the induction and maintenance of inflammatory responses. Mast cells and basophils express an array of calcium channels, which mediate responses to diverse stimuli triggered by small bioactive molecules, physicochemical stimuli and immunological inputs including antigens and direct immune cell interactions. These cells are also highly responsive to certain venoms (such as Hymenoptera envenomations), which cause histamine secretion, cytokine release and an array of pro-inflammatory functional responses. There are gaps in our understanding of the coupling of venom exposure to specific signaling pathways such as activation of calcium channels. In the present study, we performed a current survey of a model mast cell line selected for its pleiotropic responsiveness to multiple pro-inflammatory inputs. As a heterogenous stimulus, Hymenoptera venom activates multiple classes of conductance at the population level but tend to lead to the measurement of only one type of conductance per cell, despite the cell co-expressing multiple channel types. The data show that ICRAC, IARC, and TRPV-like currents are present in the model mast cell populations and respond to venom exposure. We further assessed individual venom components, specifically secretagogues and arachidonic acid, and identified the conductances associated with these stimuli in mast cells. Single-cell calcium assays and immunofluorescence analysis show that there is heterogeneity of channel expression across the cell population, but this heterogeneity does not explain the apparent selectivity for specific channels in response to exposure to venom as a composite stimulus.


Assuntos
Venenos de Artrópodes/farmacologia , Mordeduras e Picadas/imunologia , Himenópteros/fisiologia , Mastócitos/imunologia , Animais , Venenos de Artrópodes/imunologia , Venenos de Artrópodes/toxicidade , Histamina/imunologia , Humanos , Himenópteros/imunologia , Mastócitos/efeitos dos fármacos , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/imunologia
3.
Clin Toxicol (Phila) ; 57(8): 677-685, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30806093

RESUMO

Introduction: Snakes, insects, arachnids and myriapods have been linked to necrosis following envenomation. However, the pathways involved in arthropod venom-induced necrosis remain a highly controversial topic among toxinologists, clinicians and the public. On the one hand, clinicians report on alleged envenomations based on symptoms and the victims' information. On the other hand, toxinologists and zoologists argue that symptoms are incompatible with the known venom activity of target species. This review draws from the literature on arthropod envenomations, snakebite, and inflammatory processes to suggest that envenomation by a range of organisms might trigger an intense inflammatory cascade that ultimately lead to necrosis. If confirmed, these processes would have important implications for the treatment of venom-induced necrosis. Objectives: To describe two inflammatory pathways of regulated necrosis, tumour necrosis factor (necroptosis) and Neutrophil Extracellular Traps (NETosis); to discuss existing knowledge about snake venom and arachnid-induced necrosis demonstrating the involvement of tumour necrosis factor and neutrophils in the development of tissue necrosis following envenomation and to contribute to the understanding of venom-induced necrosis by arthropods and provide clinicians with an insight into little known inflammatory processes which may occur post envenomation. Methods: ISI Web of Science databases were searched using the terms "spider bite necrosis", "arthropod envenomation necrosis", "venom necrosis", "venom immune response", "loxoscelism", "arachnidism", "necroptosis venom", "necroptosis dermatitis", "tumour necrosis factor TNF venom", "scorpionism", "scolopendrism", "centipede necrosis", "NETosis venom", "NETosis necrosis". Searches produced 1737 non-duplicate citations of which 74 were considered relevant to this manuscript. Non-peer-reviewed sources or absence of voucher material identifying the organism were excluded. What is necrosis? Necrosis is the breakdown of cell membrane integrity followed by inflowing extracellular fluid, organelle swelling and the release of proteolytic enzymes into the cytosol. Necrosis was historically considered an unregulated process; however, recent studies demonstrate that necrosis can also be a programmed event resulting from a controlled immune response (necroptosis). Tumour necrosis factor and the necroptosis pathway: Tumour necrosis factor is a pro-inflammatory cytokine involved in regulating immune response, inflammation and cell death/survival. The pro-inflammatory cytokine TNF-α participates in the development of necrosis after envenomation by vipers. Treatment with TNF-α-antibodies may significantly reduce the manifestation of necrosis. Neutrophil Extracellular Traps and the NETosis pathway: The process by which neutrophils discharge a mesh of DNA strands in the extracellular matrix to entangle ("trap") pathogens, preventing them from disseminating. Neutrophil Extracellular Traps have been recently described as important in venom-induced necrosis. Trapped venom accumulates at the bite site, resulting in significant localized necrosis. Arthropod venom driving necrosis: Insects, myriapods and arachnids can induce necrosis following envenomation. So far, the processes involved have only been investigated in two arachnids: Loxosceles spp. (recluse spiders) and Hemiscorpius lepturus (scorpion). Loxosceles venom contains phospholipases D which hydrolyse sphingomyelin, resulting in lysis of muscle fibers. Subsequently liberated ceramides act as intermediaries that regulate TNF-α and recruit neutrophils. Experiments show that immune-deficient mice injected with Loxosceles venom experience less venom-induced inflammatory response and survive longer than control mice. Necrosis following Hemiscorpius lepturus stings correlates with elevated concentrations of TNF-α. These observations suggest that necrosis may be indirectly triggered or worsened by pathways of regulated necrosis in addition to necrotic venom compounds. Conclusions: Envenomation often induce an intense inflammatory cascade, which under certain circumstances may produce necrotic lesions independently from direct venom activity. This could explain the inconsistent and circumstantial occurrence of necrosis following envenomation by a range of organisms. Future research should focus on identifying pathways to regulated necrosis following envenomation and determining more efficient ways to manage inflammation. We suggest that clinicians should consider the victim's immune response as an integral part of the envenomation syndrome.


Assuntos
Venenos de Artrópodes/toxicidade , Artrópodes , Mordeduras e Picadas , Dermotoxinas/toxicidade , Dermatopatias , Animais , Venenos de Artrópodes/imunologia , Mordeduras e Picadas/imunologia , Mordeduras e Picadas/patologia , Bases de Dados Bibliográficas , Dermotoxinas/imunologia , Necrose , Dermatopatias/imunologia , Dermatopatias/patologia , Fator de Necrose Tumoral alfa/imunologia
4.
J Allergy Clin Immunol Pract ; 6(5): 1462-1482.e6, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29902530

RESUMO

Eosinophils are bone marrow-derived cells that infiltrate skin and mucous membrane in a broad spectrum of primary and reactive inflammatory diseases and malignancies. The eosinophil has potent proinflammatory activities, particularly, through the effects of its toxic granule proteins. In addition, eosinophils have prothrombotic and profibrotic activities. Eosinophil participation in the pathogenesis of certain diseases without identifiable intact eosinophil infiltration may not be recognized because eosinophil degranulation is poorly visualized on hematoxylin-and-eosin-stained histopathology sections. Eosinophil-related pathophysiology can involve virtually every component of skin. Commonly recognized dermatoses associated with eosinophils are arthropod bite and sting reactions and drug eruptions, "bugs and drugs." Skin involvement is common in eosinophil-related systemic diseases including the hypereosinophilic syndromes. Eosinophil-related pathophysiology may play a key role in numerous disorders that, therefore, may benefit from therapies targeted to reduce or eliminate eosinophils.


Assuntos
Mordeduras e Picadas/imunologia , Toxidermias/imunologia , Eosinófilos/imunologia , Síndrome Hipereosinofílica/imunologia , Pele/imunologia , Animais , Artrópodes/imunologia , Humanos , Imunoterapia/tendências , Dermatopatias
6.
Exp Dermatol ; 26(3): 263-269, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27623398

RESUMO

Little is known about the immunomodulation by tick saliva during a natural tick bite in human skin, the site of the tick-host interaction. We examined the expression of chemokines, cytokines and leucocyte markers on the mRNA levels and histopathologic changes in human skin biopsies of tick bites (n=37) compared to unaffected skin (n=9). Early tick-bite skin lesions (<24 hours of tick attachment) were characterized by a predominance of macrophages and dendritic cells, elevated mRNA levels of macrophage chemoattractants (CCL2, CCL3, CCL4) and neutrophil chemoattractants (CXCL1, CXCL8), of the pro-inflammatory cytokine, IL-1ß, and the anti-inflammatory cytokine, IL-5. In contrast, the numbers of lymphocytes and mRNA levels of lymphocyte cell markers (CD4, CD8, CD19), lymphocyte chemoattractants (CXCL9, CXCL10, CXCL11, CXCL13, CCL1, CCL22), dendritic cell chemoattractants (CCL20), and other pro- (IL-6, IL-12p40, IFN-γ, TNF-α) and anti-inflammatory cytokines (IL-4, IL-10, TGF-ß) did not differ from normal skin. With longer tick attachment (>24 hours), the numbers of innate immune cells and mediators (not significantly) declined, whereas the numbers of lymphocytes (not significantly) increased. Natural tick bites by Ixodes ricinus ticks initially elicit a strong local innate immune response in human skin. Beyond 24 hours of tick attachment, this response usually becomes less, perhaps because of immunomodulation by tick saliva.


Assuntos
Mordeduras e Picadas/imunologia , Citocinas/genética , Imunidade Celular , Ixodes/imunologia , Saliva/imunologia , Adolescente , Adulto , Idoso , Animais , Antígenos CD/metabolismo , Biópsia , Mordeduras e Picadas/genética , Mordeduras e Picadas/patologia , Estudos de Casos e Controles , Quimiocinas/genética , Células Dendríticas/imunologia , Feminino , Humanos , Imunidade Inata , Linfócitos/imunologia , Macrófagos/imunologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/imunologia , RNA Mensageiro/metabolismo , Pele/imunologia , Pele/patologia , Fatores de Tempo , Adulto Jovem
7.
J Immunol ; 195(1): 23-9, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26092814

RESUMO

Devil facial tumor disease (DFTD) is a transmissible cancer that has killed most of the Tasmanian devil (Sarcophilus harrissii) population. Since the first case appeared in the mid-1990s, it has spread relentlessly across the Tasmanian devil's geographic range. As Tasmanian devils only exist in Tasmania, Australia, DFTD has the potential to cause extinction of this species. The origin of DFTD was a Schwann cell from a female devil. The disease is transmitted when devils bite each other around the facial areas, a behavior synonymous with this species. Every devil that is 'infected' with DFTD dies from the cancer. Once the DFTD cells have been transmitted, they appear to develop into a cancer without inducing an immune response. The DFTD cancer cells avoid allogeneic recognition because they do not express MHC class I molecules on the cell surface. A reduced genetic diversity and the production of immunosuppressive cytokines may also contribute.


Assuntos
Mordeduras e Picadas/imunologia , Transmissão de Doença Infecciosa , Neoplasias Faciais/imunologia , Marsupiais/imunologia , Células de Schwann/imunologia , Animais , Mordeduras e Picadas/mortalidade , Mordeduras e Picadas/patologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Carnivoridade , Células Dendríticas/imunologia , Células Dendríticas/patologia , Neoplasias Faciais/mortalidade , Neoplasias Faciais/patologia , Feminino , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Masculino , Mortalidade , Células de Schwann/patologia , Tasmânia
8.
Infect Immun ; 82(7): 2736-45, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24733091

RESUMO

Cutaneous leishmaniasis is a sand fly-transmitted disease characterized by skin ulcers that carry significant scarring and social stigmatization. Over the past years, there has been cumulative evidence that immunity to specific sand fly salivary proteins confers a significant level of protection against leishmaniasis. In this study, we used an attenuated strain of Listeria monocytogenes as a vaccine expression system for LJM11, a sand fly salivary protein identified as a good vaccine candidate. We observed that mice were best protected against an intradermal needle challenge with Leishmania major and sand fly saliva when vaccinated intravenously. However, this protection was short-lived. Importantly, groups of vaccinated mice were protected long term when challenged with infected sand flies. Protection correlated with smaller lesion size, fewer scars, and better parasite control between 2 and 6 weeks postchallenge compared to the control group of mice vaccinated with the parent L. monocytogenes strain not expressing LJM11. Moreover, protection correlated with high numbers of CD4(+), gamma interferon-positive (IFN-γ(+)), tumor necrosis factor alpha-positive/negative (TNF-α(+/-)), interleukin-10-negative (IL-10(-)) cells and low numbers of CD4(+) IFN-γ(+/-) TNF-α(-) IL-10(+) T cells at 2 weeks postchallenge. Overall, our data indicate that delivery of LJM11 by Listeria is a promising vaccination strategy against cutaneous leishmaniasis inducing long-term protection against ulcer formation following a natural challenge with infected sand flies.


Assuntos
Proteínas de Insetos/imunologia , Leishmania major/imunologia , Leishmaniose Cutânea/prevenção & controle , Listeria monocytogenes , Psychodidae/fisiologia , Proteínas e Peptídeos Salivares/imunologia , Animais , Mordeduras e Picadas/imunologia , Mordeduras e Picadas/parasitologia , Orelha Externa/imunologia , Orelha Externa/parasitologia , Insetos Vetores/parasitologia , Vacinas contra Leishmaniose/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T/classificação , Vacinas Sintéticas
9.
Cell Immunol ; 277(1-2): 22-32, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22784562

RESUMO

Although the role of regulatory T cells (Tregs) during malaria infection has been studied extensively, such studies have focused exclusively on the role of Treg during the blood stage of infection; little is known about the detailed mechanisms of Tregs and sporozoite deposition in the dermis by mosquito bites. In this paper we show that sporozoites introduced into the skin by mosquito bites increase the mobility of skin Tregs and dendritic cells (DCs). We also show differences in MHC class II and/or CD86 expression on skin-resident dendritic cell subtypes and macrophages. From the observed decrease of the number of APCs into draining lymph nodes, suppression of CD28 expression in conventional CD4 T cells, and a low homeostatic proliferation of skin-migrated CD4 T found in nude mice indicate that Tregs may play a fundamental role during the initial phase of malaria parasite inoculation into the mammalian host.


Assuntos
Mordeduras e Picadas/imunologia , Culicidae/parasitologia , Malária/imunologia , Dermatopatias Parasitárias/imunologia , Pele/imunologia , Animais , Antígeno B7-2/biossíntese , Antígeno B7-2/imunologia , Mordeduras e Picadas/parasitologia , Proliferação de Células , Células Dendríticas/imunologia , Células Dendríticas/parasitologia , Genes MHC da Classe II/imunologia , Linfonodos/imunologia , Linfonodos/parasitologia , Macrófagos/imunologia , Macrófagos/parasitologia , Malária/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Pele/parasitologia , Esporozoítos/imunologia , Esporozoítos/parasitologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/parasitologia
11.
Int Arch Allergy Immunol ; 157(2): 176-85, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21986086

RESUMO

BACKGROUND: Immunoglobulin E (IgE) to N-glycans from plant and invertebrate glycoproteins induces extensive in vitro cross-reactivity. This study investigates the prevalence and diagnostic relevance of IgE to these N-glycans [cross-reactive carbohydrate determinants (CCDs)] in patients with suspicion of respiratory allergy. METHODS: A total of 1,025 adult subjects with symptoms of rhinitis and/or asthma from a reference allergy clinic were studied. Determinations included a structured questionnaire, skin prick tests (SPT), total IgE, a multiallergen IgE test and specific IgE (sIgE) to bromelain, MUXF (the bromelain-type N-glycan) and honeybee phospholipase-A2. Inhibition studies with CCDs were performed in selected cases. RESULTS: The prevalence of CCD sensitization (MUXF sIgE and/or bromelain-sIgE ≥0.1 kU(A)/l) was 18.0%. Male sex and atopy (SPT positivity) were associated with CCD sensitization. Sensitization was more frequent in patients sensitized to pollens than in those sensitized to mites, the most common inhalant allergens in the area. A history of Hymenoptera stings was associated with CCD sensitization and multiallergen IgE test positivity. CCD sensitization was not significantly associated with age, rural residence, alcohol consumption or smoking. Only 58 patients (5.6%) showed CCD-sIgE levels ≥0.35 kU(A)/l. CCD-induced inhibition of pollen-sIgE or mite-sIgE in patients with respective positive SPT was minimal or absent in most cases. CONCLUSIONS: In this population of predominantly mite-allergic patients, CCD sensitization is relatively rare and CCD-sIgE levels are low. Thus, CCDs do not represent a major obstacle for the diagnosis of respiratory allergy in a specialized setting. Hymenoptera stings are associated with CCD sensitization.


Assuntos
Carboidratos/imunologia , Imunoglobulina E/imunologia , Hipersensibilidade Respiratória/diagnóstico , Hipersensibilidade Respiratória/imunologia , Adolescente , Adulto , Idoso , Animais , Mordeduras e Picadas/etiologia , Mordeduras e Picadas/imunologia , Reações Cruzadas/imunologia , Epitopos/imunologia , Feminino , Humanos , Himenópteros/imunologia , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Hipersensibilidade Respiratória/epidemiologia , Fatores de Risco , Adulto Jovem
12.
Am J Dermatopathol ; 34(4): 442-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22172958

RESUMO

The histopathology of arthropod bite reactions is classically described as "dermal edema" with superficial and middle to deep dermal inflammation in a perivascular and wedge-shaped distribution. The composition of the infiltrate may vary, but a characteristic feature is the presence of prominent eosinophils between collagen bundles. Sweet syndrome, also known as acute febrile neutrophilic dermatosis, is characterized by dermal edema and a dense neutrophilic infiltrate, associated with a constellation of clinical and biological signs. We describe herein 2 cases of arthropod bite reactions with impressive clinical lesions and histopathological findings reminiscent of Sweet syndrome. However, the patients were lacking other criteria for Sweet syndrome and were diagnosed as Sweet-like reaction to arthropod bites. Pathologists should be careful in rendering a diagnosis of neutrophilic dermatosis, which requires clinicopathological correlation, and should consider arthropod bite reactions in the differential diagnosis.


Assuntos
Artrópodes , Mordeduras e Picadas/patologia , Pele/patologia , Síndrome de Sweet/patologia , Adulto , Animais , Anti-Inflamatórios/uso terapêutico , Biópsia , Mordeduras e Picadas/tratamento farmacológico , Mordeduras e Picadas/imunologia , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Pele/efeitos dos fármacos , Pele/imunologia , Síndrome de Sweet/imunologia , Resultado do Tratamento
13.
Cancer Sci ; 96(8): 519-26, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16108834

RESUMO

Hypersensitivity to mosquito bites is characterized by severe systemic as well as local symptoms, and associated with chronic active EBV infection and NK cell lymphocytosis. In this HEN disease, we investigated the response of PBMC to MSG extracts. PBMC were taken from three defined cases of HEN disease, three borderline cases, five individuals with simple exaggerated reactions to mosquito bites without systemic symptoms (simple responders), and eight healthy donors. PBMC, or purified CD4+, CD8+ or CD56+ cells, were cultured with MSG extracts prepared from each of five mosquito species to examine their proliferation and cytokine secretion. The patients with HEN disease had high stimulation indices with variations in responses to the extracts from Aedes albopictus, Aedes aegypti, Anopheles sinensis and Culex pipiens pallens. However, a non-Japan-habitant species Anopheles stephensi did not stimulate the patients' PBMC. Some borderline or simple responders showed moderate proliferation, and healthy donors had no reactive PBMC. In HEN disease, both CD56+ NK cells (producing IFN-gamma) and CD4+ Th0 cells (producing IL-4 and IFN-gamma) were increased in the blood. CD4+ cells, but not CD56+ NK cells or CD8+ cells, propagated in response to MSG extracts. However, this response of CD4+ cells and their IL-4 production were strongly enhanced by coexisting CD56+ cells. We suggest that the CD4+ T cell serving as the primary responder to MSG antigen and the NK cell functioning as the enhancer are both pathogenic in the development of HMB.


Assuntos
Mordeduras e Picadas/imunologia , Mordeduras e Picadas/virologia , Culicidae/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Herpesvirus Humano 4/imunologia , Células Matadoras Naturais/imunologia , Linfócitos T/imunologia , Animais , Humanos , Linfocitose/imunologia , Extratos de Tecidos/imunologia
14.
JAMA ; 292(21): 2614-21, 2004 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-15572719

RESUMO

CONTEXT: A frequent cause of human immunodeficiency virus (HIV)-related morbidity in sub-Saharan Africa is a commonly occurring, intensely pruritic skin rash. The resulting scars are disfiguring and stigmatizing. Despite the substantial prevalence of pruritic papular eruption (PPE) among HIV-infected Africans, the cause has been elusive. OBJECTIVE: To determine the etiology of PPE occurring in HIV-infected individuals. DESIGN, SETTING, AND PATIENTS: Cross-sectional study of HIV-infected patients with active PPE from clinics in Uganda conducted from May 19 through June 6, 2003. Enrollment occurred in the month preceding May 19. Each participant was clinically examined by 2 dermatologists, had laboratory studies performed, was administered an epidemiologic questionnaire, and had a skin biopsy of a new lesion evaluated by a dermatopathologist. MAIN OUTCOME MEASURES: Histological characteristics of new pruritic lesions. Other assessments included CD4 cell count, eosinophil count, and physician-assessed rash severity. RESULTS: Of 109 patients meeting inclusion criteria, 102 (93.6%) completed the study. The CD4 cell counts in this study population were generally low (median, 46/microL) and inversely related to increasing rash severity (median CD4 cell counts: 122 for mild, 41 for moderate, and 9 for severe; P<.001 for trend). Eighty-six patients (84%; 95% confidence interval, 77%-91%) had biopsy findings characteristic of arthropod bites. Patients with arthropod bites on biopsy had significantly higher peripheral eosinophil counts (median, 330 vs 180/microL; P = .02) and had a trend toward lower CD4 cell counts (median, 40 vs 99/microL; P = .07) than those without histological evidence of arthropod bites. CONCLUSIONS: Pruritic papular eruption occurring in HIV-infected individuals may be a reaction to arthropod bites. We hypothesize that this condition reflects an altered and exaggerated immune response to arthropod antigens in a subset of susceptible HIV-infected patients.


Assuntos
Artrópodes , Mordeduras e Picadas/imunologia , Exantema/etiologia , Infecções por HIV/imunologia , Prurigo/etiologia , Adulto , Animais , Biópsia , Mordeduras e Picadas/complicações , Mordeduras e Picadas/diagnóstico , Contagem de Linfócito CD4 , Estudos Transversais , Eosinófilos , Exantema/patologia , Feminino , Infecções por HIV/complicações , Humanos , Contagem de Leucócitos , Masculino , Prurigo/patologia , Prurido/etiologia , Prurido/patologia , Uganda
15.
Eur J Haematol ; 72(1): 73-6, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14962269

RESUMO

Epstein-Barr virus (EBV) is associated with hypersensitivity to mosquito bites (HMB) and fatal EBV-associated hemophagocytic syndrome (HPS). The prognosis of patients with chronic active EBV infection (CAEBV) is very poor. We report a rare case of an adult woman patient with a 28-yr history of HMB, who developed EBV-HPS. EBV genome was detected in the serum and peripheral blood lymphocytes. Clonal proliferation of EBV was demonstrated by Southern blot analysis using an EBV genome terminal-repeat probe. This is a very rare case of a long-term survivor with CAEBV. The patient was initially treated with immunochemotherapy and achieved complete remission. However, the patient immediately relapsed and underwent allogeneic bone marrow transplantation (BMT) from her HLA-matched brother. Peripheral blood cell recovered well, and EBV genome disappeared from the peripheral blood. Allogeneic BMT may be effective in eradicating EBV-HPS. Unfortunately, the patient died of graft vs. host disease on the 92nd day after BMT.


Assuntos
Infecções por Vírus Epstein-Barr/terapia , Adulto , Animais , Mordeduras e Picadas/imunologia , Culicidae/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Evolução Fatal , Feminino , Genoma Viral , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Humanos , Hipersensibilidade , Sobreviventes , Fatores de Tempo
16.
J Infect Dis ; 187(8): 1332-6, 2003 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-12696016

RESUMO

Information regarding the inflammatory response in African tick-bite fever (ATBF), an emerging spotted-fever-group rickettsiosis, in international travelers to sub-Saharan Africa, is scarce. Plasma/serum levels of von Willebrand factor (vWF), soluble (s) E-selectin, tumor necrosis factor-alpha, interleukin (IL)-6, interferon-gamma, IL-10, IL-13, IL-8, RANTES, macrophage inflammatory protein-1alpha, and C-reactive protein were studied, at both first presentation and follow-up, in 15 patients with travel-associated ATBF and in 14 healthy travelers who served as control subjects. Our main and novel findings are the following: (1) patients with ATBF had increased levels of vWF and sE-selectin, with a subsequent decrease at follow-up; (2) with the exception of IFN-gamma, levels of cytokines and chemokines were also increased in these patients at the first presentation; and (3) IL-10 and IL-13 tended to increase during follow-up, whereas most of the inflammatory cytokines decreased. The induction of these mediators and the balance between them may be critical both for the regulation of inflammation and for protective immunity in ATBF.


Assuntos
Mordeduras e Picadas/imunologia , Inflamação/imunologia , Inflamação/microbiologia , Infecções por Rickettsia/imunologia , Doenças Transmitidas por Carrapatos/imunologia , Carrapatos , Adulto , África , Animais , Vetores Aracnídeos , Mordeduras e Picadas/sangue , Doenças Transmissíveis Emergentes/sangue , Doenças Transmissíveis Emergentes/imunologia , Citocinas/sangue , Selectina E/sangue , Feminino , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Rickettsia/fisiologia , Infecções por Rickettsia/sangue , Doenças Transmitidas por Carrapatos/sangue , Carrapatos/microbiologia , Viagem , Fator de von Willebrand/análise
17.
J Am Acad Dermatol ; 45(4): 569-78, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11568749

RESUMO

Hypersensitivity to mosquito bites or mosquito allergy is a mysterious disorder that has been reported mainly in Japanese patients (at least 58 patients) in the first two decades of life. The skin lesion at bite sites is typically a bulla that develops into necrosis. Patients simultaneously exhibit a high temperature and general malaise and subsequently may experience lymphadenopathy and hepatosplenomegaly. Recent studies have revealed that this mosquito hypersensitivity is associated with chronic Epstein-Barr virus infection and natural killer cell leukemia/lymphoma. The natural killer cell, infected with monoclonal (or oligoclonal) Epstein-Barr virus, seems to be involved in the pathogenesis of the hypersensitivity. Half of the patients reported died of hemophagocytic syndrome (or malignant histiocytosis), granular lymphocyte proliferative disorder, or lymphomas. We propose that this disease, defined as the triad of hypersensitivity to mosquito bites, chronic Epstein-Barr virus infection, and natural killer cell leukemia/lymphoma, is a clinical entity mostly seen in Asians.


Assuntos
Mordeduras e Picadas/imunologia , Culicidae , Infecções por Vírus Epstein-Barr/complicações , Hipersensibilidade/etiologia , Células Matadoras Naturais/imunologia , Leucemia Linfoide/imunologia , Leucemia Linfoide/virologia , Adolescente , Adulto , Animais , Linfoma de Burkitt/imunologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Febre/etiologia , Humanos , Lactente , Recém-Nascido , Masculino , Necrose
18.
Artigo em Inglês | MEDLINE | ID: mdl-11039839

RESUMO

Histamine is the principal mediator released in the skin during immediate bee venom allergy but the significance of cysteinyl leukotrienes in these reactions is not known. We measured skin histamine and cysteinyl leukotriene release induced by bee venom in six sensitized beekeepers with the skin microdialysis technique. The skin was dialyzed for 2 h after skin prick test with bee venom, and the release of histamine and leukotriene C4 (LTC4) into the microdialysis fractions was measured. Leukotriene E4 (LTE) and methylhistamine excretion into the urine was assayed and whole blood histamine release test was performed. The release of histamine in the skin was variable: either high delayed, high immediate and delayed, weak release or no marked release. The histamine releasability in the skin correlated with that in whole blood. The three subjects with low histamine release exhibited high LTC4 release in the skin as well as high LTE4 excretion into the urine. Thus, the histamine and LTC4 releases were inversely associated with each other. These differences may explain the variation in the clinical reaction by bee stings in sensitized beekeepers.


Assuntos
Venenos de Abelha/efeitos adversos , Venenos de Abelha/imunologia , Liberação de Histamina , Hipersensibilidade Imediata/imunologia , Leucotrieno C4/metabolismo , Animais , Abelhas , Mordeduras e Picadas/imunologia , Feminino , Humanos , Hipersensibilidade Imediata/metabolismo , Imunoglobulina E/sangue , Leucotrieno C4/urina , Masculino , Metilistaminas/urina , Microdiálise , Doenças Profissionais/imunologia , Pele/metabolismo , Testes Cutâneos
19.
Mol Immunol ; 33(7-8): 681-9, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8760280

RESUMO

The purpose of the present work was to determine the ability of BgTX peptides, corresponding to the various loops and exposed regions of alpha-bungarotoxin (BgTX) and representing regions that are recognized by B and/or T cells, to stimulate protective immunity in mice against in vivo challenge with BgTX. The BgTX LD50 values in non-immune mice or mice that had been immunized with proteins and peptides unrelated to BgTX were: Balb/c, 0.128 microgram/g; SJL, 0.156 microgram/g. Immunization of Balb/c and SJL mice with each of the synthetic peptides in its free form afforded considerable protection against BgTX poisoning. Peptides L1 (residues 3-16), L2 (residues 26-41) and C-tail (residues 66-74) of BgTX were the most protective and mice immunized with these peptides survived LD50 values that were three times higher than control mice. Immunization with an equimolar mixture of the three peptides was even more protective and these mice survived even higher challenge doses of BgTX (4.6-fold higher than LD50 of controls; i.e. protection index, PI = 4.6). An OVA conjugate carrying all three peptides, when used as an immunogen, conferred extremely high protection (PI > or = 18.1) which was almost double the protection obtained by BgTX immunization (PI = 9.7). Thus, the conjugate of the three peptides should serve as an effective vaccine against BgTX poisoning. Furthermore, these results with BgTX peptides should serve as a prototype for the design and synthesis of peptide vaccines against other members of this large family of toxins which include both long and short neurotoxins as well as cytotoxins.


Assuntos
Mordeduras e Picadas/prevenção & controle , Bungarotoxinas/imunologia , Bungarotoxinas/toxicidade , Peptídeos/imunologia , Vacinas Sintéticas/imunologia , Sequência de Aminoácidos , Animais , Mordeduras e Picadas/imunologia , Bungarotoxinas/administração & dosagem , Relação Dose-Resposta Imunológica , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Peptídeos/administração & dosagem , Peptídeos/síntese química , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/química
20.
Rev. Inst. Med. Trop. Säo Paulo ; 37(1): 71-4, jan.-fev. 1995.
Artigo em Inglês | LILACS | ID: lil-154336

RESUMO

Neste trabalho foram determinadas a sensibilidade e a especificidade da tecnica imunoenzimatica (ELISA) desenvolvida por CHAVEZ-OLORTEGUI et al. para detectar antigenos circulantes de veneno em pacientes picados por Tityus serrulatus. A media mais dois desvios padrao da observancia do soro de 100 pacientes controles foi utilizada como limite entre teste positivo e teste negativo ("cutoff"). A especificidade do ELISA foi igual a 97,0 por cento . A sensibilidade do metodo, quando incluidos pacientes classificados como casos leves, moderados e graves de escorpionismo, foi de 39,3 por cento e aumentou para 94,7 por cento quando considerados apenas os casos moderados e graves. Estes resultados mostram que o ELISA pode ser utilizado para deteccao de antigenos toxicos circulantes em pacientes com manifestacoes sistemicas de envenenamento escorpionico mas nao deve ser empregado no estudo de pacientes que apresentam apenas dor no local da picada (casos leves). O tempo necessario para a realizacao do ELISA e superior a 1 hora. Portanto, o teste tem sua utilizacao limitada para o diagnostico de envenenamento, mas pode construir um instrumento util para o estudo da cinetica de neutralizacao do veneno pelo antiveneno especifico.


Assuntos
Humanos , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Ensaio de Imunoadsorção Enzimática , Escorpiões/classificação , Picada de Aranha/diagnóstico , Antivenenos/administração & dosagem , Antivenenos/imunologia , Mordeduras e Picadas/imunologia , Fatores Socioeconômicos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA