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Abstract: Monocytes play a central role in the immune system by producing and reacting to different soluble factors. Cytokine dysregulation is an hallmark in HIV-infected individuals and it is one of the most significant factors leading to impaired immunity in HIV/AIDS disease. This study investigates the possibility of modulation in the secretion of some inflammatory cytokines and chemokines induced by HIV p17 in monocytes. The results show that p17, while ineffective on resting monocytes, exerts an inflammatory action on IL-4 mediated inhibition of TNF-α and IFN-γ production induced by IL-15 stimulation. In addition, p17 is able to reduce MIP-1α secretion, but unable to influence IL-6 production. The ability of HIV p17 to contribute to an altered pattern of secreted soluble factors might imply a key role for this viral protein in the development of AIDS pathogenesis. [Copyright &y& Elsevier]

Background Products based on hydrolysed cow milk proteins or amino acid mixtures are recommended in children with cow's milk hypersensitivity. However, some children who are allergic to cow's milk and who clinically react to substitute milk formulas have been observed. Objective To determine the tolerance and allergenicity of protein hydrolysate or amino acid-derived formulas in children with IgE-mediated cow's milk allergy. Methods Twenty children with positive cow's milk challenges, positive skin prick tests and/or serum-specific IgE antibodies to cow's milk were selected. Oral challenges, skin prick tests and serum-specific IgE antibodies to extensively hydrolysed whey formula, partially hydrolysed whey formula, extensively hydrolysed casein formula and amino acid-derived formula were performed. Results Five out of 17 (5/17) children reacted to partially hydrolysed whey formula, (3/16) to extensively hydrolysed whey formula, (2/10) to amino acid-derived formula, (1/16) to extensively hydrolysed casein formula. Only extensively hydrolysed casein formula was tolerated by at least 90% (with 95% confidence intervals) of children. Hydrolysates provoked early and delayed clinical reactions, amino acid mixtures only delayed reactions. Partially hydrolysed whey formula elicited a significantly higher number of positive skin prick test reactions than other formulas. Two children had specific IgE antibodies to extensively hydrolysed whey formula, one to partially hydrolysed whey formula, one to extensively hydrolysed casein formula and none to amino acid-derived formula. Conclusion In this study, none of the cow's milk substitutes has been found to be non-allergenic. Our results suggest that in children with IgE-mediated cow's milk allergy, the first ingestions of extensively hydrolysed cow's milk protein formulas require strict medical supervision because of immediate reactions. This is not the case for amino acid-derived formula. Moreover, our data suggest that... [ABSTRACT FROM AUTHOR]

High-grade gliomas are aggressive tumors of the central nervous system characterized by endothelial cell proliferation and a high degree of vascularity. Conventional antitumoral treatments (i.e., surgery, radiotherapy, and chemotherapy) do not achieve satisfactory results (median survival in glioblastoma 12-18 months). It has been suggested that immunotherapy with xenogenic endothelial cells could slow tumor growth rate in a number of tumors in a murine model, but the study did not include gliomas. In experiments performed in our laboratory, vaccination with proliferating bovine aortic endothelium increased survival time in Fischer rats inoculated intracerebrally with 9L. Immunotherapy was also able to reduce the growth of subcutaneously injected 9L gliosarcoma cells in Fischer rats and to decrease microvessel density within the tumors, in the absence of major organ toxicity. Immunoglobulins (Ig) in the sera from vaccinated rats stained bovine aortic endothelium as well as human umbilical vein endothelium in active proliferation. Moreover, immune sera from immunized rats stained microvessels of human malignant glioma specimens and vessels of intracerebrally implanted tumors. Two proteins of MW of 11 and 19 kDa were identified by Western blot as targets of Ig elicited by vaccination. A possible future development is to select peptides/proteins suitable for vaccination in humans, avoiding the biohazards connected with xenogenic whole-cell vaccination. [ABSTRACT FROM AUTHOR]

Background. Hydrolysed casein and whey protein formulas have been developed with the aim of preventing sensitization in infants at high risk of cow milk allergy. Subsequently these products have also been used for treatment of children with cow milk allergy. However, severe reactions have occurred in some allergic infants led with these formulas raising doubts about their absolute safety and suggest the need for developing in vitro techniques for detection of eventual residual allergenic activity in such preparations. Objectives Our purpose was to evaluate the usefulness of monoclonal and polyclonal antibodies against casein components (α β and κ casein) as reagents for the detection of the residual antigenic activity of casein components in several hydrolysed formulas, Methods The monoclonal and polyclonal antibodies were produced according to standard procedures by immunizing female Balb/e mice with casein fraction (a mixture of α β and κ casein). ELISA assays were developed to test the specificity of the antibodies and to detect and evaluate the amount of residual antigenic activity of the casein components in hydrolysed formulas. Results Use of polyclonal antiserum specific For casein allowed detection of residual antigenic activity of casein components in all partial hydrolysates and in the two extensive whey protein hydrolysates in the amounts ranging from 0.05 to 0.67% of total protein. No such activity was detectable in either the two extensive casein hvdrolysates tested or the aminoacid based formula. The polyclonal antiserum proved to be more suitable than monoclonals for detecting residual antigenic activity in the hydrolysates. The monoclonal antibodies were directed against epitopes expressed on different casein components. Conclusions In this study the ELISA inhibition assay with polyclonal antibodies specific for casein components of cow milk proved to be a sensitive method for estimating residual antigenicity in the hydrolysed formulas commercially available for infants with cow milk allergy suggesting their potential application for the quality control of hypoallergenic infant formulas. [ABSTRACT FROM AUTHOR]

Background Partial and extensive hydrolysed protein formulae have been developed to lower or eliminate the antigenicity of' milk protein\. Although normally well tolerated. extensive hydrolysates have been reported to induce serious allergic reactions in very sensitive children. Moreover, clinical practice has often raised concern about the role of partial hydrolysates in Cow's milk allergy prevention .Objective: Strating from these considerations. we used anti-casein monoclonal anti- bodies to evaluate the presence of residual antigenic activity in both partially and extensively protein hydrolysates. Methods: Electrophoretic analyses associated with immunoblotting technique we it performed using nine protein-enriched commercial formulae. ResuIts: The presence of different amounts of residual intact cow's milk proteins and or polypeptidic material with conserved antigenic activity (according to the extensive or partial hydrolysis) was verified in most milk-based samples considered. Conclusion: The use of monoclonal antibodies and immunoblotting could be useful For the quality control of commercial `hypoallergemie' formulate. [ABSTRACT FROM AUTHOR]

Background Extensively hydrolysed protein formulas are widely used as an alternative diet for children with cow's milk allergy. Partially hydrolysed protein formulas have been noted in some studies as useful in the prevention of allergy in infants at high risk of atopy. Although normally well tolerated. these 'hypoallergenic' products have been reported to cause serious immunological reactions in very sensitive subjects. Objective Starting from these considerations, we studied some commercial hydrolysed formulas in search of biological data supporting the observed clinical reactions. Methods We set up an electrophoretic method sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) which allowed us to study the molecular weight of peptides contained in hydrolysed products. Then, using the immunoblotting technique we evaluated the reactivity of circulating IgE (from serum of children allergic to cow's milk proteins) with the residual intact proteins and with the peptides present in these formulas. Results Both group of milk proteins (caseins and whey proteins) were important allergens for children included in this study. The presence of high-molecular polypeptides was shown in partial hydrolysed formulas as such and in extensive hydrolysed products after protein enrichment by trichloroacetic acid (TCA) precipitation. Intact residual proteins were mainly responsible for the formation of IgE-antigen complexes observed in immunoblotting. More rarely. polypeptides of partial hydrolysed formulas were involved in immunological responses. Conclusions Both partial and extensive hydrolysed formulas could induce clinical reactions in very sensitive subjects. These responses are mainly associated with allergy to the small amounts of residual intact proteins. [ABSTRACT FROM AUTHOR]