La finanza etica: il caso Etica s.g.r.

Lo scopo del lavoro è lo studio delle forme di investimento orientate all’universo etico e la dimostrazione della convenienza da parte di investitori, aziende, associazioni ed organizzazioni ad investire in fondi socialmente responsabili, attraverso l’analisi dei fondi Valori Responsabili della società di gestione del risparmio Etica s.g.r

Immunogenicity of a free synthetic peptide: carrier-conjugation enhances antibody affinity for the native protein.

The synthetic peptide 166-174 of hCS sequence, corresponding to an antigenic determinant of the protein, was used to elicit MAbs to the native hCS molecule. The synthetic peptide was administered according to different immunization protocols to BALB/c mice, both in the free form or conjugated to carrier proteins. Spleens and popliteal lymph nodes from primed mice were fused with a myeloma cell line to produce MAbs, and selected clones were characterized for isotype and affinity. Spleen fusions gave rise to IgM MAbs, whereas lymph node fusions gave preferentially IgG MAbs. No correlation was found between antibody class and affinity since affinity is highly increased by carrier-conjugation, while it did not enhance IgG production. The free synthetic peptide showed a low immunogenicity: affinities of MAbs produced ranged from 10(5) to 10(7) l/mole, an average 1000-fold lower than the values obtained with carrier-conjugated peptide. In one case, however, carrier conjugation did not give rise to anti-hCS MAbs. Overall, these studies provide a rational approach to the production of anti-protein MAbs by synthetic peptide immunization and offer the opportunity to obtain MAbs of the desired isotype and affinity

New insight in the interaction between the gp120 and the HIV receptor in human sperms

The human immunodeficiency virus (HIV) can infect some cell types which lack CD4. Galactosylceramide, a glycolipid present in the nervous system and colonic epithelial cells, has been implicated in the virus entry in these cells. Our data demonstrate that the HIV surface glycoprotein gp120 binds to the galactosyl-alkyl-acylglycerol (GalAAG), a glycolipid structurally related to galactosylceramide present on the surface membrane of the spermatozoa. In this paper, we review our previous data and further confirm the specificity of the interaction between this galactoglycerolipid and the gp120. Consistent with the structural similarity to galactosylceramide, the sperm GalAAG is capable of specifically binding the gp120. The specificity of the binding of antibodies antigalactosylceramide and the gp120 to the sperm extract and to the purified GalAAG fraction prepared from the same extract has been demonstrated utilizing an ELISA assay which favors sensitivity and specificity. Immunofluorescence and immunoelectron microscopy data show a different localization for the GalAAG and its sulfated form the seminolipid (SGalAAG). The GalAAG is preferentially localized in the equatorial segment and the middle piece of the sperm tail, while the seminolipid is widely distributed on the membrane of the spermatozoa. These data indicate that human sperm express on their surface membrane a glycolipid similar in structure to galactosylceramide, the receptor for HIV identified in the CD4 cells, that could function as a HIV receptor and possibly be implicated in its transmission

Production and characterization of monoclonal antibodies to anti-human chorionic somatomammotropin by immunization with two free synthetic peptides.

The peptides corresponding to the fragments 135-140 and 166-174 of human chorionic somatomammotropin (hCS) were synthesized, and used to raise monoclonal antibodies to the native hCS molecule. The synthetic peptides were injected into BALB/c mice in the free form, i.e. not conjugated to a carrier, and the spleens were fused with Sp2/01Ag8 myeloma line to produce monoclonal antibodies. The antibodies produced belonged to the IgM and IgG classes and, once purified by affinity chromatography on hCS-Sepharose, they were covalently coupled to macroporous polystyrene beads and characterized by competitive radioimmunoassay. Their affinity constants were determined by elaborating the radioimmunoassay data by nonlinear regression analysis and they were found to range from 10(5) to 10(6) M-1. The evaluation of the affinity constant of the antibodies produced is always important as a measure of the immunogenicity of an antigen, particularly when synthetic peptides are used as immunogens