Phage Display-based Strategies for Cloning and Optimization of Monoclonal Antibodies Directed against Human Pathogens

In the last two decades, several phage display-selected monoclonal antibodies (mAbs) have been described in the literature and a few of them have managed to reach the clinics. Among these, the anti-respiratory syncytial virus (RSV) Palivizumab, a phage-display optimized mAb, is the only marketed mAb directed against microbial pathogens. Palivizumab is a clear example of the importance of choosing the most appropriate strategy when selecting or optimizing an anti-infectious mAb. From this perspective, the extreme versatility of phage-display technology makes it a useful tool when setting up different strategies for the selection of mAbs directed against human pathogens, especially when their possible clinical use is considered. In this paper, we review the principal phage display strategies used to select anti-infectious mAbs, with particular attention focused on those used against hypervariable pathogens, such as HCV and influenza viruses.     

Radiometric and signal-to-noise ratio properties of multiplex dispersive spectrometry

Recent theoretical investigations have shown important radiometric disadvantages of interferential multiplexing in Fourier transform spectrometry that apparently can be applied even to coded aperture spectrometers. We have reexamined the methods of noninterferential multiplexing in order to assess their signal-to-noise ratio (SNR) performance, relying on a theoretical modeling of the multiplexed signals. We are able to show that quite similar SNR and radiometric disadvantages affect multiplex dispersive spectrometry. The effect of noise on spectral estimations is discussed.     

The loyal member effect: On the preference for ingroup members who engage in exclusive relations with the ingroup.

The goal of this article was to investigate an indirect form of intergroup differentiation in children in the context of racial attitudes: the preference for ingroup members who interact positively with other ingroup members rather than with outgroup members. Study 1 confirmed this general hypothesis with preschool and 1st-grade children, demonstrating that respondents preferred the ingroup member who played only with other ingroup members, evaluated this child more positively, and felt more similar to him or her. Studies 2 and 3 tested the boundary conditions of the phenomenon. Study 4 analyzed developmental changes demonstrating that the effect is no longer observed among 9- to 11-year-old children. Overall, these studies suggest that engaging in positive interactions with the outgroup might have its costs in terms of a relative devaluation and rejection by one's peers. Results are discussed by stressing the importance of intragroup processes for the regulation of intergroup relations among very young children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Changes in Radiosensitivity to Gamma-Rays of Lymphocytes from Hyperthyroid Patients Treated with I-131

This study investigated the peripheral blood lymphocytes (PBL) response to a dose of γ-rays in patients treated with radioiodine (I-131) for hyperthyroidism vs. healthy controls, to gain information about the individual lymphocytes’ radio-sensitivity. Blood samples were taken from 18 patients and 10 healthy donors. Phosphorylated histone variant H2AX (γ-H2AX) and micronuclei (MN) induction were used to determine the change in PBL radio-sensitivity and the correlations between the two types of damage. The two assays showed large inter-individual variability in PBL background damage and in radio-sensitivity (patients vs. healthy donors). In particular, they showed an increased radio-sensitivity in 36% and 33% of patients, decrease in 36% and 44%, respectively. There was a scarce correlation between the two assays and no dependence on age or gender. A significant association was found between high radio-sensitivity conditions and induced hypothyroidism. PBL radio-sensitivity in the patient group was not significantly affected by treatment with I-131, whereas there were significant changes inter-individually. The association found between clinical response and PBL radio-sensitivity suggests that the latter could be used in view of the development of personalized treatments.     

Using Copy Number Alterations to Identify New Therapeutic Targets for Bladder Carcinoma

Bladder cancer represents the ninth most widespread malignancy throughout the world. It is characterized by the presence of two different clinical and prognostic subtypes: non-muscle-invasive bladder cancers (NMIBCs) and muscle-invasive bladder cancers (MIBCs). MIBCs have a poor outcome with a common progression to metastasis. Despite improvements in knowledge, treatment has not advanced significantly in recent years, with the absence of new therapeutic targets. Because of the limitations of current therapeutic options, the greater challenge will be to identify biomarkers for clinical application. For this reason, we compared our array comparative genomic hybridization (array-CGH) results with those reported in literature for invasive bladder tumors and, in particular, we focused on the evaluation of copy number alterations (CNAs) present in biopsies and retained in the corresponding cancer stem cell (CSC) subpopulations that should be the main target of therapy. According to our data, CCNE1, MYC, MDM2 and PPARG genes could be interesting therapeutic targets for bladder CSC subpopulations. Surprisingly, HER2 copy number gains are not retained in bladder CSCs, making the gene-targeted therapy less interesting than the others. These results provide precious advice for further study on bladder therapy; however, the clinical importance of these results should be explored.     

The 2-5A system in viral infection and apoptosis

The 2-5A system is an established endogenous antiviral pathway. Interferon treatment of cells leads to an increase in basal, but latent, levels of 2-5A-dependent RNase (RNase L) and the family of 2'-5' oligoadenylate synthetases (OAS). Double-stranded RNA, thought to be derived from viral replication intermediates, activates OAS. Activated OAS converts ATP into unusual short 2'-5' linked oligoadenylates called 2-5A [ppp5'(A2'p5')2A]. The 2-5A binds to and activates RNase L which cleaves single stranded RNA with moderate specificity for sites 3' of UpUp and UpAp sequences, and thus leads to degradation of cellular rRNA. During apoptosis, generalized cellular RNA degradation, distinct from the differential expression of mRNA species that may regulate specific gene expression during apoptosis, has been observed. The mechanism of RNA breakdown during apoptosis has been commonly considered a non-specific event that reflects the generalized shut down of translation and homeostatic regulation during cell death. Due to the similar RNA degradation that occurs during both apoptosis and viral infection we investigated the potential role of RNase L in apoptosis. To investigate whether RNase L activity could lead to apoptosis, NIH3T3 cells were transfected with a lac-inducible vector containing the human RNase L gene. Treatment of these cells with isopropylthiogalactoside (IPTG) caused loss of cell viability that was confirmed as an apoptotic cell death by morphological and biochemical criteria. Similarly, specific allosteric activation of endogenous RNase L by introduction of 2-5A directly into L929 cells also induced apoptosis. In L929 cells poly(I).poly(C) treatment in combination with interferon caused an increase in apoptosis whereas neither interferon or double stranded RNA alone altered cell viability. Therefore, increased expression or activation of RNase L causes apoptosis. Inhibition of RNase L, specifically with a dominant negative mutant, suppressed poly(I)Ypoly(C)-induced apoptosis in interferon-primed fibroblasts. Poliovirus, a picornovirus with a single-stranded RNA genome, causes apoptosis of HeLa cells. Expression of the dominant negative inhibitor of RNase L in HeLa prevented virus-induced apoptosis and maintained cell viability. Thus, reduction or inhibition of RNase L activity prevents apoptosis. Both apoptosis and the 2-5A system can provide defense against viral infection in multicellular organisms by preventing production and therefore spread of progeny virus. RNase L appears to function in both mechanisms, therefore, initiation of apoptosis may be one mechanism for the antiviral activity of the 2-5A system.     

Result of an antifibrinolytic treatment using tranexamic acid for the reduction of blood-loss during and after tonsillectomy

Blood loss during and after tonsillectomy was assessed in 80 patients, 40 of whom were treated with tranexamic acid. A statistically significant reduction of blood loss (28%) was observed in this group during operation. Later bleedings occurred only in 27.5% (control: 67.5%) and stopped after 2 h (mean of control: 5.6h). Bleedings in the tranexamic acid group were mild and scarcely required other hemostyptic treatment, while in the control group some patients had to be treated with etamsylate or fibrogen for a longer period to stop bleeding. Tranexamic acid appears to be an effective and well-tolerated agent for reduction of blood loss caused by local hyperfibrinolysis.     

Alpha-1-thymosin and transcatheter arterial chemoembolization in hepatocellular carcinoma patients: a preliminary experience

BACKGROUND/AIMS: To evaluate the tolerability and therapeutic potential of the immunostimulating adjuvant alpha-1-thymosin in patients with hepatocellular carcinoma. METHODOLOGY: Twelve patients with hepatocellular carcinoma were treated with alpha-1-thymosin (900 micrograms/m2 subcutaneously twice per week for 6 months) and transcatheter arterial chemoembolization and compared to a historical control group (matched for gender, age, Okuda staging, Child's score, alpha-fetoprotein serum levels and viral infection) treated with transcatheter arterial chemoembolization alone. RESULTS: No severe side effects were recorded in the 2 treatment groups. The combination of alpha-1-thymosin plus transcatheter arterial chemoembolization resulted in a longer survival that reached statistical significance 7 months after the end of treatment (p < 0.05). Patients receiving combined treatment demonstrated a significant increase in peripheral blood mononuclear cells expressing CD3 (p < 0.05) and CD8 (p < 0.025) 3 months after beginning treatment. They also had a significant increase (p < 0.05) in CD16+ and CD56+ cells after 1 month, and a slight reduction in mononuclear cells expressing CD25, a marker for cell activation. No alterations in the response to phytohemagglutinin stimulation were seen during the alpha-1-thymosin treatment. CONCLUSIONS: The absence of toxicity and the favourable effects observed in this open study call for a double blind control study to confirm the efficacy of the combined treatment.