CD4-mediated Anchoring of the Seminal Antigen gp17 onto the Spermatozoon Surface.

A soluble 17 kDa glycoprotein, namely gp17, was previously isolated from human semen and used to obtain mouse monoclonal or chicken polyclonal antibodies. This protein was shown to bind CD4+ T-cells and to soluble recombinant CD4 in vitro. Here, we report that the anti-gp17 monoclonal antibodies are captured by ejaculated spermatozoa and that gp17-like antigens are released by cell acid extraction. Immunoblotting experiments with monoclonal antibodies indicated that SDS-lysates from spermatozoa contain proteins with the same electrophoretic and antigenic properties of CD4 and gp17. Anti-CD4 mouse monoclonal antibodies were used to coprecipitate from NP40-lysate proteins reacting with chicken anti-gp17 antibodies. Analytical chromatography demonstrated that a number of gp17-like forms are present in the seminal plasma, put that only the 1 kDa species can be detected in the spermatozoa lysate. This protein was localised by immunofluorescence on the post-acrosomal region of the spermatozoon. The same surface domain was also reactive with anti-CD4 antibodies. After treatment to induce in vitro capacitation, gp17 was detected all over the spermatozoon head. Conversely, only a minor part of the treated spermatozoa exhibited CD4 immunostaining, which remained localised on the post-acrosomal region. The possible function of CD4 and gp17 on male germ cells is discussed

Evaluation of oxidative damage in cheese produced from bovine or water buffalo milk.

Technological processes represent the main source of protein and lipid oxidation in food. The oxidative status was determined in a soft Italian cheese, namely mozzarella, produced from water buffalo or bovine milk. The amount of protein-bound carbonyls, dityrosine and alpha-lactalbumin aggregates were measured to evaluate the extent of protein oxidation. The alpha-tocopherylquinone/alpha-tocopherol ratio and the trolox-equivalent antioxidant capacity were used as redox markers in the fat fraction. The levels of protein-bound carbonyls and alpha-lactalbumin aggregates were found significantly higher in mozzarella from bovine than in that from buffalo. On the contrary, higher amounts of redox markers were found in buffalo mozzarella. The levels of dityrosine aggregates were similar in the two groups of cheese. The data suggest that protein and fat are more protected against structure oxidative alterations in buffalo mozzarella than in bovine mozzarell

Failure to increase glucose consumption through the pentose phosphate pathway results in the death of glucose-6-phosphate dehydrogenase gene-deleted mouse embryonic stem cells subjected to oxidative stress.

Mouse embryonic stem (ES) glucose-6-phosphate (G6P) dehydrogenase-deleted cells (G6pd Delta), obtained by transient Cre recombinase expression in a G6pd-loxed cell line, are unable to produce G6P dehydrogenase (G6PD) protein (EC 1.1.1.42). These G6pd Delta cells proliferate in vitro without special requirements but are extremely sensitive to oxidative stress. Under normal growth conditions, ES G6pd Delta cells show a high ratio of NADPH to NADP+ and a normal intracellular level of GSH. In the presence of the thiol scavenger oxidant, azodicarboxylic acid bis[dimethylamide], at concentrations lethal for G6pd Delta but not for wild-type ES cells, NADPH and GSH in G6pd Delta cells dramatically shift to their oxidized forms. In contrast, wild-type ES cells are able to increase rapidly and intensely the activity of the pentose-phosphate pathway in response to the oxidant. This process, mediated by the [NADPH]/[NADP+] ratio, does not occur in G6pd Delta cells. G6PD has been generally considered essential for providing NADPH-reducing power. We now find that other reactions provide the cell with a large fraction of NADPH under non-stress conditions, whereas G6PD is the only NADPH-producing enzyme activated in response to oxidative stress, which can act as a guardian of the cell redox potential. Moreover, bacterial G6PD can substitute for the human enzyme, strongly suggesting that a relatively simple mechanism of enzyme kinetics underlies this phenomenon

Identification of an inflammation-associated psychosis onset subgroup by applying unsupervised machine learning to whole-blood expression levels of immune gene transcripts

Nowadays, the lack of quantitative criteria to resolve the diagnostic heterogeneity of psychotic onsets limits the development of safer and more effective treatments. Therefore, the hypothesis to integrate multimodal data to uncover biological subtypes of psychosis has risen [1,2]. Here we explored the existence of subgroups of patients affected by first episode psychosis (FEP) with a possible immunopathogenic basis.To do this, we designed a computational model that use unsupervised machine learning to cluster a sample of 127 FEP patients and 117 healthy controls (HC), based on the peripheral blood concentrations of 12 immune gene transcripts which demonstrated to classify with high accuracy between FEP patients and healthy subjects in a previous study [3]. To validate the model, we applied a resampling strategy based on the half-splitting of the total sample. Further, we tested the correlation between the subgroups and clinical, neuropsychological and brain structural variables.In both the discovery and validation samples, the model identified a FEP cluster characterized by the high expression of inflammatory and immune-activating genes (IL1b, CCR7 and IL12a) and of a single immune counterregulatory gene (CCR3)[4] and a further cluster consisting of equal number of FEP and HC subjects, which did not show a relative over or under expression of any immune marker (balanced subgroup). Also, none of the subgroups were related to specific symptoms dimensions or longitudinal diagnosis. FEP patients included in the balanced immune subgroup showed a reduced left hippocampal volume and a left supramarginal and lateroccipital cortexes’ thinning. These correlations seem to support an opposite pattern in the correspondent brain area of the inflammatory subgroup [5].Our results demonstrated the existence of a FEP patients’ subgroup that present a prominent activation of the inflammatory response. This evidence may pave the way to sample stratification in future trials aiming to develop personalized diagnostic tools and therapies targeting specific immunopathogenic pathways of psychosis onsets