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Background: Fynomers are small binding proteins (7 kDa) derived from the human SH3 domain of Fyn kinase. They can be engineered to yield specific and high-affinity binding domains to target proteins of interest. In the past, we have isolated Fynomers with excellent physico-chemical properties binding to 16 different antigens. One important application of the Fynomer technology represents the genetic fusion of a Fynomer to an antibody to provide bispecific fusion proteins with enhanced activity compared to the unmodified antibody. Method: Using phage display technology we have isolated Fynomers binding to an epitope on HER2 which is different from the epitopes recognized by trastuzumab and pertuzumab. After genetic fusion of the HER2 binding Fynomers to pertuzumab the resulting bispecific fusion proteins were evaluated in vitro and in vivo for their antitumoral activity. Results: The fusion of Fynomers to pertuzumab did not alter the favorable biophysical properties of pertuzumab: First, the Fynomer-antibody fusion proteins could be purified with the same high yields from the supernatant of transiently transfected CHO cells as the unmodified antibody pertuzumab (in the range of 100 mg/L). Second, the purified fusion proteins were monomeric and showed no signs of aggregation even after four months of storage at 4 °C or-20 °C in PBS as determined by size exclusion chromatography. Third, the fusion of Fynomers to antibodies did not alter their Fc-mediated effector functions. Antibody-dependent cellular cytotoxicity (ADCC) was maintained, and the affinity to the neonatal Fc-receptor (FcRn) was similar as observed for pertuzumab. In addition, the bispecific Fynomer-antibody fusion proteins demonstrated excellent growth inhibition of tumor cells in vitro compared to pertuzumab and trastuzumab. In particular, the most potent molecule COVA208 exhibited impressive efficacy in vivo in tumor xenograft mouse models. Conclusion: These encouraging preclinical results indicate that the bispecific Fynomer-antibody fusions have highly promising properties with a great potential for further preclinical and clinical development, both alone and in combination with trastuzumab. [ABSTRACT FROM AUTHOR]

Background: Hemoglobinopathies are the commonest genetic defect worldwide (7% of the world's population has at least one hemoglobin mutation). Although prenatal screening for hemoglobinopathies is not obligatory during pregnancy in Italy, it is offered to women by the Italian National Health Service in the pre-conception phase. The screening of newborns is a valid alternative, and has been adopted in various European countries, albeit in a piecemeal fashion. Neonatal screening has the advantage of providing early diagnosis of a hemoglobinopathy. Here we report the findings from the experience with neonatal screening in Friuli-Venezia Giulia since 2010., Materials and Methods: The hemoglobinopathy screening project in Friuli-Venezia Giulia, a Region in north Italy, began in November 2010. High-performance liquid chromatography was performed on dried blood spot samples collected by obstetric nurses from neonates within 5-8 days after birth., Results: From 2010 to 2019, 11,956 newborns were screened, and abnormal hemoglobin was found in 519 of them (4.34%): the variants identified included HbS, HbC, HbD, HbE and HbX. More specifically, the HbS variant was observed in 347 (2.9%) newborns and the homozygous pattern was identified in 24 (0.2%) cases. The screening also detected two cases of β-thalassemia major., Discussion: We report our experience of 10 years of screening newborns for hemoglobinopathies in the Region of Friuli-Venezia Giulia, in which 7.7% of people come from malaria-endemic areas. Increased mobility and migratory flows bringing in hemoglobinopathy carriers from endemic areas have led to an increase in mutations in non-malarial countries, with a current incidence of around 4% in the newborns we tested. This means that hemoglobinopathies can be described as a rare condition. Our data show that incidence rates are comparable to those of other inherited disorders such as phenylketonuria, thereby justifying the inclusion of the test for hemoglobinopathies into screening programs for rare diseases.

Biologic treatment options such as tumor necrosis factor (TNF) inhibitors have revolutionized the treatment of inflammatory diseases, including rheumatoid arthritis. Recent data suggest, however, that full and long-lasting responses to TNF inhibitors are limited because of the activation of the pro-inflammatory TH17/interleukin (IL)-17 pathway in patients. Therefore, dual TNF/IL-17A inhibition is an attractive avenue to achieve superior efficacy levels in such diseases. Based on the marketed anti-TNF antibody adalimumab, we generated the bispecific TNF/IL-17A-binding FynomAb COVA322. FynomAbs are fusion proteins of an antibody and a Fyn SH3-derived binding protein. COVA322 was characterized in detail and showed a remarkable ability to inhibit TNF and IL-17A in vitro and in vivo. Through its unique mode-of-action of inhibiting simultaneously TNF and the IL-17A homodimer, COVA322 represents a promising drug candidate for the treatment of inflammatory diseases. COVA322 is currently being tested in a Phase 1b/2a study in psoriasis ( ClinicalTrials.gov Identifier: NCT02243787).

Upregulation of HER2 is a hallmark of 20% to 30% of invasive breast cancers, rendering this receptor an attractive target for cancer therapy. Although HER2-targeting agents have provided substantial clinical benefit as cancer therapeutics, there is a need for the development of new agents aiming at circumventing anti-HER2 resistance. On the basis of the approved antibody pertuzumab, we have created a panel of bispecific FynomAbs, which target two epitopes on HER2. FynomAbs are fusion proteins of an antibody and a Fyn SH3-derived binding protein. One bispecific FynomAb, COVA208, was characterized in detail and showed a remarkable ability to induce rapid HER2 internalization and apoptosis in vitro. Moreover, it elicited a strong inhibition of downstream HER2 signaling by reducing HER2, HER3, and EGFR levels in vitro and in vivo. Importantly, COVA208 demonstrated superior activity in four different xenograft models as compared with the approved antibodies trastuzumab and pertuzumab. The bispecific FynomAb COVA208 has the potential to enhance the clinical efficacy and expand the scope of HER2-directed therapies, and delineates a paradigm for designing a new class of antibody-based therapeutics for other receptor targets., (©2014 American Association for Cancer Research.)

Here, we report the first comprehensive study of Bartonella henselae gene expression during infection of human endothelial cells. Expression of the main cluster of upregulated genes, comprising the VirB type IV secretion system and its secreted protein substrates, is shown to be under the positive control of the transcriptional regulator BatR. We demonstrate binding of BatR to the promoters of the virB operon and a substrate-encoding gene and provide biochemical evidence that BatR and BatS constitute a functional two-component regulatory system. Moreover, in contrast to the acid-inducible (pH 5.5) homologs ChvG/ChvI of Agrobacterium tumefaciens, BatR/BatS are optimally activated at the physiological pH of blood (pH 7.4). By conservation analysis of the BatR regulon, we show that BatR/BatS are uniquely adapted to upregulate a genus-specific virulence regulon during hemotropic infection in mammals. Thus, we propose that BatR/BatS two-component system homologs represent vertically inherited pH sensors that control the expression of horizontally transmitted gene sets critical for the diverse host-associated life styles of the alphaproteobacteria.