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E Profumo

Publications and source records attributed to E Profumo.

At least 19 recordsLinked to original sources

Screening of an Echinococcus granulosus cDNA library with IgG4 from patients with cystic echinococcosis identifies a new tegumental protein involved in the immune escape.

The worldwide problem of chronic Echinococcus granulosus disease calls for new parasite-derived immunomodulatory molecules. By screening an E. granulosus cDNA library with IgG4 from patients with active cystic echinococcosis, we identified a cDNA that encodes a predicted partial protein that immunofluorescence studies localized in the protoscolex tegument and on the germinal layer of cyst wall. We named this protein EgTeg because the 105 amino acid sequence scored highest against a family of Schistosoma tegumental proteins. Evaluating the role of EgTeg in the human early inflammatory response we found that EgTeg significantly inhibited polymorphonuclear cell (PMN) chemotaxis. Cytometric analysis of intracellular cytokines disclosed a significantly higher percentage of cells producing IL-4 than IFN-gamma (P = 0.001, Student's t-test) in T lymphocytes from patients with cystic echinococcosis stimulated with EgTeg. EgTeg induced weak Th1-dependent proliferation in 42% of patients' peripheral blood mononuclear cells. In immunoblotting (IB) analysis of total IgG and IgG subclass responses to EgTeg in patients with cystic echinococcosis, patients with other parasitoses, patients with cystic lesions and healthy controls, total IgG specific to EgTeg yielded high sensitivity (73%) but low specificity (44%) precluding its use in immunodiagnosis. Conversely, IgG4 specific to EgTeg gave acceptable sensitivity (65%) and high specificity (89%) suggesting its use in immunodiagnosis to confirm ultrasound documented cysts suggestive of E. granulosus. Because the new tegumental antigen EgTeg inhibits chemotaxis, induces IL-4-positive T lymphocytes and noncomplement fixing antibodies (IgG4) it is an immunomodulatory molecule associated with chronic infection.

Amino Acid Sequence↗

Morphological analysis of cell subpopulations within carotid atherosclerotic plaques.

Atherosclerosis is considered a chronic inflammatory process, prompted by lipid accumulation and propagated by cell-mediated mechanisms. The present work was undertaken to clarify this process by characterizing cellular components of inflammatory infiltrate localized within atheroma. Cryostat sections of atherosclerotic lesions obtained from human carotid endarterectomy were analysed immunohistochemically by using monoclonal and polyclonal antibody directed against T cell subpopulations (CD3, CD4, CD8), B cells (CD20), plasma cells (CD138), macrophages (CD14), mast cells (anti-tryptase). Our results assess that T cells are the predominant cell type among plaque infiltrating inflammatory cells. B cells were detected near the lipid core of atheroma and clusters of plasma cells were observed within cellular infiltrates in most plaques. Numerous tryptase positive mast cells were noticed in many areas of complicated lesions. Our results indicate the presence of many inflammatory cells within type V and VI atherosclerotic plaques, suggesting the involvement of those cells in plaque progression. In fact it was previously shown that stability of atherosclerotic lesions is influenced by mast cell-released matrix metalloproteinases which induce plaque rupture and by cytokines and chemokines which increase local inflammatory response and are produced by lymphocytes and macrophages.

Aged↗

Echinococcus granulosus-specific T-cell lines derived from patients at various clinical stages of cystic echinococcosis.

To investigate the role of T lymphocytes in the immune response to Echinococcus granulosus, using sheep hydatid fluid (SHF) and antigen B (AgB), we generated T-cell lines from patients with active, transitional and inactive hydatid cysts. We established 16 T-cell lines, eight specific to SHF and eight specific to AgB. At surface phenotyping 88-98% of cells displayed the helper/inducer CD4 antigen. In all patients, at all clinical stages of hydatid cyst disease, T-cell stimulation with SHF and AgB invariably amplified a large number of almost identical Vbeta subfamily fragments. Irrespective of antigen-specificity, the two cell lines from the patient with an inactive cyst had a Th1 profile, because they exclusively expressed and produced IFN-gamma. Conversely, the T-cell lines derived from the seven patients with active and transitional hydatid cysts had mixed Th1/Th2 and Th0 clones. The functional characteristics of the 16 T-cell lines differed markedly in the various clinical stages of cystic echinococcosis, thus providing new in vitro evidence that Th1 lymphocytes contribute decisively to the inactive stage of hydatid disease, Th2 lymphocytes in the active and transitional stages. The parasite-specific T-cell lines, especially the two Th1 lines from the patient with an inactive cyst, may help identify Th1 protective epitopes on SHF and AgB.

Adolescent↗

Screening of a HUAEC cDNA library identifies actin as a candidate autoantigen associated with carotid atherosclerosis.

The humoral immune response to endothelium has a pivotal role in the development of atherosclerosis. Using a molecular method, we sought to identify endothelial autoantigens in carotid atherosclerosis. Immunoscreening of a HUAEC expression library with IgG from a pool of two sera from patients with carotid atherosclerosis identified a clone specific to actin. We evaluated actin-specific IgG reactivity in patients with carotid atherosclerosis and compared responses with those in patients with systemic lupus erythematosus and type 1 diabetes mellitus and in healthy subjects. Enzyme-linked immunoassay detected actin-specific IgG in a significantly higher percentage of sera from patients with atherosclerosis and systemic lupus erythematosus than from healthy subjects (16/61, 26% and 13/33, 39%versus 2/41, 5%, P = 0.012 and P < 10(-4), by chi2 test). Mean optical density values were significantly higher in patients than in healthy subjects (P < 10(-4) by Student's t-test). Patients with atherosclerosis and uncomplicated plaques had significantly higher serum anti-actin IgG reactivity than those with complicated plaques (P = 0.048 by Student's t-test). Our findings suggest that actin is an autoantigenic molecule of potential clinical interest in carotid atherosclerosis.

Actins↗

Critical points in the immunodiagnosis of cystic echinococcosis in humans.

This study discusses the immunodiagnosis of cystic echinococcosis (ce, caused by Echinococcus granulosus). The detection by immunoblotting of antibodies specific for the 8 kDa subunit of antigen B and in particular the IgG4 subclass expression, seems the most promising serodiagnostic tool. Despite the development of molecular methods, nowadays there is no standard, highly sensitive, and specific test available for antibody detection in CE. Furthermore, because serological tests can give only a limited support to clinical findings there is a clear need for new advances in immunodiagnosis of E. granulosus infection.

Antibodies, Helminth↗

Molecular and immunological characterization of the C-terminal region of a new Echinococcus granulosus Heat Shock Protein 70.

By screening an expression library of Echinococcus granulosus with IgE from sera of patients with cystic echinococcosis (CE) and allergic reactions, we isolated the C-terminal region of a new heat shock protein (HSP)70 of E. granulosus. The protein, named Eg2HSP70, has close homology with the C-terminal region of Dermatophagoides farinae and human HSP70. We investigated the humoral and cell-mediated immune responses to this antigen in patients with CE grouped according to the presence of allergic reactions. Immunoblotting detected total IgG, IgG4 and IgE specific to Eg2HSP70 (83% of sera contained IgG, 31% IgG4 and 57% IgE). No significant difference was found in immunoglobulin percentages according to the presence of allergic reactions. Immunoblotting inhibition showed that no IgG or IgE specific to Eg2HSP70 cross-reacted with D. farinae or human HSP70. Eg2HSP70-stimulated PBMC from 26 patients produced significantly greater amounts of TNF-alpha, IFN-gamma, and IL-10 than unstimulated cultures in all patients, irrespective of the presence of allergic reactions (P < 0.05). They also produced significantly greater amounts of IL-4 than unstimulated cultures exclusively in patients with allergic reactions (P < 0.05). These findings show that Eg2HSP70 is a new antigenic molecule inducing both B and T cell responses.

Adult↗

Cytokine expression in circulating T lymphocytes from patients undergoing carotid endarterectomy.

AIM: We investigated a possible relationship of cytokine expression and phenotype features of circulating T lymphocytes with the histological type of atherosclerotic plaque removed during carotid endarterectomy. METHODS: Peripheral blood samples were taken from 20 patients with carotid atherosclerosis and from 8 healthy blood donors. Patients were divided into 2 groups according to the histological type of their atherosclerotic plaques (types V and VI). Expression of intracellular tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, interleukin-4 (IL-4), and of surface antigens (CD4, CD8, CD45RA, CD45RO, T cell receptor (TCR) alpha/beta, TCR gamma/delta) in circulating T lymphocytes was determined by 3-colour cytofluorimetric analysis. RESULTS: The percentage of T lymphocytes primed for TNF-alpha, IFN-gamma and IL-4 was higher in blood samples from patients than from healthy subjects; the difference was statistically significant for TNF-alpha-producing cells (p=0.01). In patients, the percentage of TNF-alpha-producing cells was significantly higher in the CD4+ subset than in the CD8+ subset (p=10(-4)). The percentage of TNF-alpha-, IFN-gamma- and IL-4-primed cells was higher in patients with type VI plaques (complicated lesions) than in patients with type V plaques (less complicated lesions). The difference was statistically significant for TNF-alpha-primed cells (p=0.05). No statistically significant differences were found in T cell phenotype features among patients or between patients and healthy subjects. CONCLUSION: Our results suggest a relationship between the percentage of circulating T lymphocytes expressing TNF-alpha and possibly IFN-gamma and IL-4 and the histological type of atherosclerotic plaque in patients with carotid artery disease.

Aged↗

Immunological characterization of Echinococcus granulosus cyclophilin, an allergen reactive with IgE and IgG4 from patients with cystic echinococcosis.

By immunological screening of a cDNA library derived from protoscoleces of Echinococcus granulosus with IgE from patients with cystic echinococcosis (CE) and allergic manifestations, we isolated a protein identical to E. granulosus cyclophilin. The protein, named EA21, has close homology with Malassezia furfur cyclophilin allergen (Mal f 6) and with human cyclophilin. Using immunoblotting (IB) with a polyclonal antibody specific to EA21, we identified E. granulosus cyclophilin both in protoscoleces and in sheep hydatid fluid. Of the 58 sera from patients with CE, 29 (50%) were IgE positive to EA21, whereas, despite the high sequence homology, none were IgE positive to Mal f 6 or human cyclophilin. Only 26 of the 58 patients (45%) had IgG specific to EA21, whereas all patients (100%) had IgG specific to Mal f 6 and human cyclophilin. IB analysis showed that serum IgE-binding reactivity to EA21 differed significantly in patients with and without allergic reactions (20 of 25, 80% versus nine of 33, 27%; P < 10(-4)). Conversely, five of the 25 patients who had CE-related allergic manifestations (20%) and 21 of the 33 who did not (63%) had specific IgG4 (P = 10(-3)) and total IgG to EA21. EA21 induced a proliferative response in 15 of 19 (79%) patients' PBMC regardless of the allergic manifestations, but it induced no IL-4 production. Overall, these findings suggest that E. granulosus cyclophilin is a conserved, constitutive, parasite protein that does not cross-react with cyclophilins from other organisms and is involved in the allergic symptoms related to CE.

Adolescent↗

Long-term serological evaluation of patients with cystic echinococcosis treated with benzimidazole carbamates.

Seeking better immunological markers indicating the long-term outcome of cystic echinococcosis (CE) after chemotherapy we studied 23 patients receiving albendazole, clinically followed for 8 years, and grouped ultrasonographically according to therapeutic outcome. Antibody responses against a partially purified fraction of hydatid fluid (HFF) and antigen B (AgB) were evaluated by indirect haemagglutination (IHA), ELISA and immunoblotting (IB). Although IHA titres varied over the course of treatment, differences in mean antibody titres to HFF between groups were significant only at 4 years (P = 0.031). IgG isotype expression remained unchanged during follow-up whereas IgE expression decreased in patients with cured or stable disease. AgB disclosed higher IgG4 expression (P < 10(-4); P = 0.025) and lower IgG1 expression than HFF (P < 10(-4); P = 0.022). IHA antibody titres were higher in patients with progressive than in those with cured or stable disease, even in those with the same cyst type. ELISA isotype profiles differed between groups, particularly for type CE 3, 4 and 5 cysts: higher serum IgG1 and IgG3, lower IgG4 and IgE in patients with cured or stable disease. Although combined serological testing provides scarce information on the long-term outcome of CE after chemotherapy it may be useful for reviewing in a retrospective study the outcome of a cyst and for assessing the host-parasite relationship.

Adult↗

Elongation factor 1 beta/delta of Echinococcus granulosus and allergic manifestations in human cystic echinococcosis.

Allergic reactions, such as urticaria, itching and anaphylactic shock, often complicate the course of cystic echinococcosis (CE). To investigate the role of the IgE-immunoreactive recombinant Echinococcus granulosus elongation factor-1 beta/delta (EgEF-1 beta/delta) in the allergic disorders during CE we determined humoral and cell-mediated responses to this antigen in patients with CE grouped according to the clinical presence or absence of allergic reactions. Immunoblotting analysis showed that serum IgE-binding reactivity to EgEF-1 beta/delta differed significantly in patients with and without allergic reactions (38 of 42, 90% vs. 31 of 56, 56%; P < 10(-4)). EgEF-1 beta/delta induced a proliferative response in 14 of 19 (74%) patients' peripheral blood mononuclear cells (PBMC) irrespective of the allergic manifestations and skewed Th1/Th2 cytokine activation towards a preferentially Th2 polarization. Epitope mapping identified an immunodominant epitope of 18 residues with 78% identity and 89% similarity with an IgE-immunoreactive Strongyloides stercoralis antigen. Overall these findings suggest that EgEF-1 beta/delta is an allergenic molecule that may be a general marker of the intensity of CE immune response and that could lead to a deeper understanding of the specific antigen-induced mechanisms underlying allergic reactions in the human host.

Adult↗

Modulation of human immune response by Echinococcus granulosus antigen B and its possible role in evading host defenses.

By directly suppressing the function of certain immune cell subsets and by stimulating other cell populations related to immunopathology, parasite-derived substances play an important role in the chronic establishment of parasitic disease. Our objective was twofold: (i) to investigate further the role of Echinococcus granulosus antigen B (AgB) in the human early inflammatory response by determining its effect on polymorphonuclear cell (PMN) random migration, chemotaxis, and oxidative metabolism and (ii) to determine its action in acquired immunity by evaluating AgB and sheep hydatid fluid (SHF)-driven Th1 (gamma interferon [IFN-gamma] and interleukin 12 [IL-12]) and Th2 (IL-4 and IL-13) cytokine production by peripheral blood mononuclear cells (PBMC) from 40 patients who had cured or stable or progressive cystic echinococcosis. AgB significantly inhibited PMN recruitment but left their random migration and oxidative metabolism unchanged. Patients' PBMC stimulated with AgB produced IL-4 and IL-13 but did not produce IL-12. They also produced significantly lower IFN-gamma concentrations than did PBMC stimulated with SHF (P = 10(-5)). AgB skewed the Th1/Th2 cytokine ratios towards a preferentially immunopathology-associated Th2 polarization, predominantly in patients with progressive disease. AgB-stimulated patients' PBMC also proliferated less than SHF-stimulated PBMC (P = 9 x 10(-3)). In vitro Th2 cytokine production was reflected in vivo by elevated specific immunoglobulin E (IgE) and IgG4 antibodies binding to AgB. These findings confirm that AgB plays a role in the escape from early immunity by inhibiting PMN chemotaxis. They also add new information on the host-parasite relationship, suggesting that AgB exploits the activation of T helper cells by eliciting a nonprotective Th2 cell response.

Adult↗

Native and recombinant antigens in the immunodiagnosis of human cystic echinococcosis.

To evaluate the diagnostic sensitivity and specificity of immunoelectrophoresis (IEP), indirect haemagglutination (IHA), enzyme-linked immunosorbent assay (ELISA) and immunoblotting (IB), we compared their ability in detecting IgG antibodies to a hydatid fluid fraction (HFF) and to native and recombinant antigen B of Echinococcus granulosus. We tested sera from patients who had cystic echinococcosis (CE) grouped according to their type of cysts (n = 204), from patients with other parasitic diseases (n = 21), lung or liver carcinomas (n = 6) or serous cysts (n = 26) and from healthy controls (n = 90). HFF-IB gave the highest sensitivity (80%) followed by ELISA (72%), IHA (54%) and IEP (31%), respectively. The diagnostic sensitivity significantly (P < 0.01) decreased as cysts matured from type I-II to type VII. Recombinant and native antigen B-IB yielded similar sensitivity (74%). A large number of clinically or surgically confirmed CE patients (20%) resulted negative. In these patients' sera, IB to assess the usefulness of the recombinant E. granulosus elongation factor-1 beta/delta in detecting IgE antibodies yielded 33% of positivity. Our findings underline the need to standardize techniques and antigenic preparations and to improve the performance of immunodiagnosis by characterizing new antigens and detecting distinct immunoglobulin classes.

Animals↗

Serum cytokine detection in the clinical follow up of patients with cystic echinococcosis.

The relation of serum cytokine levels and outcome of chemotherapy was evaluated in 15 patients with cystic echinococcosis. Serum IL-4, IL-10 and interferon-gamma (IFN-gamma) concentrations were determined by ELISA before and after a 3-month course of albendazole treatment: at least one serum sample per patient from 13 patients (87%) contained measurable amounts of IL-4; samples from five patients (33%) measurable amounts of IL-10 and samples from only two patients (13%) measurable amounts of IFN-gamma. Clinical assessment at 1 year after the end of therapy showed that 11 of the 15 patients had responded clinically. Seven of these patients had lower IL-4 serum concentrations, two had unchanged and two undetectable amounts (pre- versus post-therapy, n = 11, P = 0.008). Conversely, of the patients who did not respond, three had higher and one patient unchanged serum IL-4 concentrations. Serum IL-10 10 levels also decreased in all patients who responded (3/5) and increased in all patients who did not (2/5). No association was found between cytokine concentrations and cyst characteristics or antibody levels. Overall these data suggest that serum IL-4 detection may be useful in the follow up of patients with cystic echinococcosis.

Adult↗

Cytokine gene expression in peripheral blood mononuclear cells (PBMC) from patients with pharmacologically treated cystic echinococcosis.

The influence of pharmacological treatment on the immune response of patients with Echinococcus granulosus infection was evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) to determine mRNA expression for IL-12 p35, IL-12 p40, interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha) and IL-4 in PBMC from 12 patients before and after chemotherapy and from seven uninfected controls. Most patients' PBMC showed measurable amounts of IL-12 p35, IL-4, IFN-gamma and TNF-alpha mRNA in parasite antigen-stimulated and unstimulated cultures. Conversely, IL-12 p40 mRNA was detected almost exclusively in successfully treated patients (86%) after therapy. In these patients semiquantitative analysis of RT-PCR products showed a significant difference between IL-12 p40 mRNA mean levels before and after therapy (P = 0.03 in parasite antigen-stimulated cultures; P = 0.001 in unstimulated cultures). IL-4 mRNA was weakly expressed before therapy and more highly so after treatment in both groups of patients and under both culture conditions; IL-4 mRNA reached its highest level in post-therapy PBMC from patients in whom therapy failed (stimulated cultures). IFN-gamma and TNF-alpha mRNA expression increased in patients who responded to therapy and decreased in patients who did not. In contrast to IL-12 p35, IFN-gamma and TNF-alpha mRNAs, IL-12 p40 and IL-4 mRNAs were detected exclusively in patients, suggesting a close relationship between these two cytokines and cystic echinococcosis. Our findings indicate that chemotherapy influences the immune response, thus determining changes in Th1/Th2 cytokine mRNA patterns, predominantly in IL-12 p40 and IL-4 mRNA expression.

Adult↗

Cytokine patterns in seropositive and seronegative patients with Echinococcus granulosus infection.

To investigate the involvement of immunological variables, including the Th1/Th2 balance, in the mechanisms underlying seronegativity in cystic echinococcosis (CE), Th1 and Th2 cytokines were evaluated in ELISA determining IFN-gamma, IL-4, -5 and -10 production in peripheral blood mononuclear cell (PBMC) cultures from 16 patients (six seronegative and ten seropositive) with CE and from six healthy donors. Patients who had undetectable antibody levels in their sera invariably produced no IL-5 and scarce IL-4 and -10 (Th2 response); both groups of patients produced similar amounts of IFN-gamma; (Th1 response). The analysis of host clinical features and cyst characteristics shows that these variables do not explain the lack of detectable serum antibody levels. These findings suggest that seronegativity arises because unknown host or parasite factors, or both, cause inadequate Th2 cell activation thus reducing production of Th2 cytokines, including IL-5, the cytokine primarily implicated in immunoglobulin expression in CE.

Adult↗

New perspectives in the immunology of Echinococcus granulosus infection.

This article reviews the role of cytokines and immunoglobulin isotypes in the clinical outcome of E. granulosus infection. The coexistence of elevated quantities of IFN-gamma, IL-4, IL-5, IL-6 and IL-10 observed in most of hydatid patients supports Th1 and Th2 cell activation in human hydatidosis. In particular, Th1 cell activation seems to be related to protective immunity, Th2 cell activation to susceptibility to disease. Analysis of immunoglobulin isotypes expression reveals that the percentage of IgE responses decreases in patients parallelling to their response to chemotherapy and, among the IgG isotypes, only IgG3 and IgG4 appear related to therapy.

Animals↗