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The ASTRI Mini-Array is a next-generation system of nine imaging atmospheric Cherenkov telescopes that is going to be built at the Observatorio del Teide site. After a first phase, in which the instrument will be operated as an experiment prioritizing a schedule of primary science cases, an observatory phase is foreseen in which other significant targets will be pointed. We focus on the observational feasibility of extragalactic sources and on astrophysical processes that best complement and expand the ASTRI Mini-Array core science, presenting the most relevant examples that are at reach of detection over long-term time scales and whose observation can provide breakthrough achievements in the very-high energy extragalactic science. Such examples cover a wide range of $\gamma$-ray emitters, including the study of AGN low states in the multi-TeV energy range, the possible detection of Seyfert galaxies with long exposures and the searches of dark matter lines above 10 TeV. Simulations of the presented objects show that the instrument performance will be competitive at multi-TeV energies with respect to current arrays of Cherenkov telescopes., Comment: 27 pages, 10 figures, 7 tables, published on JHEAp

SARS‑CoV‑2 mostly affects the respiratory system with clinical patterns ranging from the common cold to fatal pneumonia. During the first wave of the COVID-19 pandemic, owing to the high number of patients who were infected with SARS‑CoV‑2 and subsequently recovered, it has been shown that some patients with post-COVID-19 terminal respiratory failure need lung transplantation for survival. There is increasing evidence coming from worldwide observations that this procedure can be performed successfully in post-COVID-19 patients. However, owing to the scarcity of organs, there is a need to define the safety and efficacy of lung transplant for post-COVID-19 patients as compared to patients waiting for a lung transplant for other pre-existing conditions, in order to ensure that sound ethical criteria are applied in organ allocation. The Milan's Policlinic Lung Transplant Surgery Unit, with the revision of the National Second Opinion for Infectious Diseases and the contribution of the Italian Lung Transplant Centres and the Italian National Transplant Centre, set up a pivotal observational protocol for the lung transplant of patients infected and successively turned negative for SARS‑CoV‑2, albeit with lung consequences such as acute respiratory distress syndrome or some chronic interstitial lung disease. The protocol was revised and approved by the Italian National Institute of Health Ethics Committee. Description of the protocol and some ethical considerations are reported in this article.

Supplemental Figures S1-S8, supplemental methods

Functional activity of ABCB1 shown for HCT15, but not for NCI-N87 or NCI-N87-S120

PDF file - 1.5 MB, Reversed-phase HPLC analyses for cleavage of ME-capped CL2E-SN-38 by cathepsin-B

Molecular structure of fumitremorgin C

Labetuzumab govitecan (IMMU-130), an antibody–drug conjugate (ADC) with an average of 7.6 SN-38/IgG, was evaluated for its potential to enhance delivery of SN-38 to human colonic tumor xenografts. Mice bearing LS174T or GW-39 human colonic tumor xenografts were injected with irinotecan or IMMU-130 (SN-38 equivalents ∼500 or ∼16 μg, respectively). Serum and homogenates of tumors, liver, and small intestine were extracted, and SN-38, SN-38G (glucuronidated SN-38), and irinotecan concentrations determined by reversed-phase HPLC. Irinotecan cleared quickly from serum, with only 1% to 2% injected dose/mL after 5 minutes; overall, approximately 20% was converted to SN-38 and SN-38G. At 1 hour with IMMU-130, 45% to 63% injected dose/mL of the SN-38 was in the serum, with >90% bound to the ADC over 3 days, and with low levels of SN-38G. Total SN-38 levels decreased more quickly than the IgG, confirming a gradual SN-38 release from the ADC. AUC analysis found that SN-38 levels were approximately 11- and 16-fold higher in LS174T and GW-39 tumors, respectively, in IMMU-130–treated animals. This delivery advantage is amplified >30-fold when normalized to SN-38 equivalents injected for each product. Levels of SN-38 and SN-38G were appreciably lower in the liver and small intestinal contents in animals given IMMU-130. On the basis of the SN-38 equivalents administered, IMMU-130 potentially delivers >300-fold more SN-38 to CEA-producing tumors compared with irinotecan, while also reducing levels of SN-38 and SN-38G in normal tissues. These observations are consistent with preclinical and clinical data showing efficacy and improved safety. Mol Cancer Ther; 17(1); 196–203. ©2017 AACR.

PDF file - 60 KB, Reversed-phase HPLC analyses of cathepsin B incubates and buffer control incubates of ME-CL2A-SN-38, pH 5, 37 degrees Celsius. Values represent % of applied product.

PDF file - 59 KB, Reversed-phase HPLC analyses of cathepsin B incubates and buffer control incubates of ME-CL2E-SN-38, pH 5, 37 degrees Celsius. Values represent % of applied product.

CD74 is an attractive target for antibody–drug conjugates (ADC), because it internalizes and recycles after antibody binding. CD74 mostly is associated with hematologic tumors but is expressed also in solid cancers. Therefore, ADCs of the humanized anti-CD74 antibody, milatuzumab, were examined for the therapy of CD74-expressing solid tumors. Milatuzumab–doxorubicin and two milatuzumab–SN-38 conjugates with cleavable linkers, differing in their stability in serum and how they release SN-38 in the lysosome, were prepared. CD74 expression was determined by flow cytometry and immunohistology. In vitro cytotoxicity and in vivo therapeutic studies were conducted in the human cancer cell lines A-375 (melanoma), HuH-7 and Hep-G2 (hepatoma), Capan-1 (pancreatic), NCI-N87 (gastric), and Raji Burkitt lymphoma. The milatuzumab–SN-38 ADC was compared with SN-38 ADCs prepared with anti-Trop-2 and anti-CEACAM6 antibodies in xenografts expressing their target antigens. Milatuzumab–doxorubicin was most effective in the lymphoma model, whereas in A-375 and Capan-1 solid tumors, only milatuzumab–SN-38 showed a therapeutic benefit. Despite much lower surface expression of CD74 than Trop-2 or CEACAM6, milatuzumab–SN-38 had similar efficacy in Capan-1 as anti-Trop-2–SN-38, but in NCI-N87, anti-CEACAM6 and anti-Trop-2 conjugates were superior. Studies in two hepatoma lines at a single dose level showed significant benefit over saline controls but not against an irrelevant immunoglobulin G conjugate. CD74 is a suitable target for ADCs in some solid tumor xenografts, with efficacy largely influenced by uniformity of CD74 expression and with SN-38 conjugates providing the best therapeutic responses; SN-38 conjugates were preferable in solid cancers, whereas doxorubicin ADC was better in lymphoma tested. Mol Cancer Ther; 12(6); 968–78. ©2013 AACR.

HLA-DR is a member of the MHC class II antigen family expressed on hematologic and solid tumors. Antibodies directed against HLA-DR have demonstrated some clinical success, but toxicities limited development. IMMU-140 is an anti–HLA-DR antibody–drug conjugate composed of the active metabolite of irinotecan, SN-38, conjugated to a humanized anti–HLA-DR IgG4 antibody (IMMU-114); the IgG4 naked antibody is devoid of immune functions. Our aim was to determine if SN-38, the metabolite of a drug not commonly used in hematopoietic cancers, would be effective and safe when targeted to HLA-DR–expressing tumors. IMMU-140 had dual-therapeutic mechanisms, as evidenced by its retention of nonoverlapping anti–HLA-DR nonclassical apoptotic signaling and classical apoptosis mediated by its SN-38 payload. In seven human disease models [acute lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL), multiple myeloma (MM), acute myeloid leukemia (AML), diffuse large B-cell lymphoma (DLBCL), Hodgkin lymphoma (HL), and melanoma], IMMU-140 provided significant therapeutic efficacy compared with controls, in vitro, in 3D spheroid models, and in vivo. Except for MM and HL, IMMU-140 imparted significantly improved antitumor effects compared with parental IMMU-114. Even in intractable AML and ALL, where IMMU-114 only had modest antitumor effects, IMMU-140 therapy mediated >80% improvement in survival. Therapy was well tolerated, as demonstrated by no marked loss in body weight. Combined with doxorubicin, IMMU-140 produced significantly greater antitumor effects in HL than with monotherapy and without any added toxicity. The dual-therapeutic action of IMMU-140 resulted in promising therapeutic activity in a range of hematopoietic tumors and melanoma, and therefore warrants clinical development. Mol Cancer Ther; 17(1); 150–60. ©2017 AACR.

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Relative mRNA levels of ABCG2 determined by RT-qPCR

Supplementary Figure S9. Induction of cytokine release by (19)-3s and 19-3 BiTE from PBMCs in the presence of Raji NHL cells. Results show the levels of TNF-α, IFN-γ and IL-6 after 20-h treatment with titrations of bsAb.

Supplemental Data Table S1. Area under the curve comparisons between IMMU-140 treated A-375 melanoma-bearing mice and all other treatment groups; Fig. S1. Synthesis Scheme for CL2A-SN-38; Fig. S2. Fluorescent Images of A-375 Spheroids Stained with PI and Calcein AM; Fig. S3. Survival Curves of IMMU-140 versus IMMU-114 Treatment of Disseminated Xenograft Disease Models of Human ALL, AML, MM, and CLL; Fig. S4. Tolerability of IMMU-140 Combined with Doxorubicin or Bortezomib in SCID Mice; Fig. S5. HLA-DR a-Chain Expression on Hematological Cancer Xenografts.

PDF file - 718 KB, (A) Release of doxorubicin from milatuzumab (hLL1)-doxorubicin conjugate at pH 5, 37 degrees Celsius and (B) in serum at 37 degrees Celsius

PDF file - 2 MB, Immunohistological assessment of the distribution of CEACAM6 and Trop-2 in formalin-fixed, paraffin-embedded xenografts of human cancer cell lines

Supplementary Table S1. Extraction efficiency for isolation of SN-38 in buffer with or without human serum albumin (HSA) or from the ADC with or without acid hydrolysis followed by extraction; Supplementary Figure S1. Schematic depiction of the conjugation of CL2A-SN-38 to mildly reduced IgG yielding site-specifically coupled SN-38 to 8 well-defined sites; Supplementary Figure S2. CL2A-SN38 amide capped with N-acetylcysteine; Supplementary Figure S3. SDS-Page gels comparing profiles for labetuzumab (unconjugated hMN-14 IgG) and labetuzumab govitecan (CL2A-SN-38 conjugated hMN-14 IgG; IMMU-130); Supplementary Figure S4. In vitro cell binding assay performed on LS174T cells, evaluating the binding of unconjugated hMN-14 IgG and SN-38-conjugated hMN-14 IgG (IMMU-130); Supplementary Figure S5. Stability of IMMU-130 in serum from different sources; Supplementary Figure S6. Evaluation of lactone ring stability of the CL2A-linked SN-38 compared to SN-38 at pH 7.4.

Molecular Structure of IMMU-132

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Purpose: Evaluate the efficacy of an SN-38-anti-Trop-2 antibody–drug conjugate (ADC) against several human solid tumor types, and to assess its tolerability in mice and monkeys, the latter with tissue cross-reactivity to hRS7 similar to humans.Experimental Design: Two SN-38 derivatives, CL2-SN-38 and CL2A-SN-38, were conjugated to the anti-Trop-2–humanized antibody, hRS7. The immunoconjugates were characterized in vitro for stability, binding, and cytotoxicity. Efficacy was tested in five different human solid tumor-xenograft models that expressed Trop-2 antigen. Toxicity was assessed in mice and in Cynomolgus monkeys.Results: The hRS7 conjugates of the two SN-38 derivatives were equivalent in drug substitution (∼6), cell binding (Kd ∼ 1.2 nmol/L), cytotoxicity (IC50 ∼ 2.2 nmol/L), and serum stability in vitro (t/½ ∼ 20 hours). Exposure of cells to the ADC demonstrated signaling pathways leading to PARP cleavage, but differences versus free SN-38 in p53 and p21 upregulation were noted. Significant antitumor effects were produced by hRS7-SN-38 at nontoxic doses in mice bearing Calu-3 (P ≤ 0.05), Capan-1 (P P P Conclusions: The anti-Trop-2 hRS7-CL2A-SN-38 ADC provides significant and specific antitumor effects against a range of human solid tumor types. It is well tolerated in monkeys, with tissue Trop-2 expression similar to humans, at clinically relevant doses, and warrants clinical investigation. Clin Cancer Res; 17(10); 3157–69. ©2011 AACR.

Supplementary sections, including additional Materials and Methods, as well as Results and Tables. Table S1. SN-38 and SN-38G standard curves using triplicate dilutions of each concentration with single HPLC run. Table S2. SN-38 extraction efficiency. Table S3. Area under the curve (AUC) analysis of various products in the serum of nude mice given irinotecan or IMMU-132. Table S4. In vitro glucuronidation assay. Table S5. Analysis of products in the large intestine of animals given irinotecan or IMMU-132 (Study 2). Values represent the mean {plus minus} SD (N = 3) and are expressed in µg.

Ranpirnase (Rap), an amphibian RNase, has been extensively studied both preclinically and clinically as an antitumor agent. Rap can be administered repeatedly to patients without any untoward immune response, with reversible renal toxicity reported to be dose limiting. To enhance its potency and targeted tumor therapy, we describe the generation of a novel IgG-based immunotoxin, designated 2L-Rap(Q)-hRS7, comprising Rap(Q), a mutant Rap with the putative N-glycosylation site removed, and hRS7, an internalizing, humanized antibody against Trop-2, a cell surface glycoprotein overexpressed in variety of epithelial cancers. The immunotoxin was generated recombinantly by fusing Rap(Q) to each of the two hRS7 light (L) chains at the NH2 terminus, produced in stably transfected myeloma cells, purified by Protein A, and evaluated by a panel of in vitro studies. The results, including size-exclusion high-performance liquid chromatography, SDS-PAGE, flow cytometry, RNase activity, internalization, cell viability, and colony formation, showed its purity, molecular integrity, comparable affinity to hRS7 for binding to several Trop-2–expressing cell lines of different cancer types, and potency to inhibit growth of these cell lines at nanomolar concentrations. In addition, 2L-Rap(Q)-hRS7 suppressed tumor growth in a prophylactic model of nude mice bearing Calu-3 human non–small cell lung cancer xenografts, with an increase in the median survival time from 55 to 96 days (P < 0.01). These results warrant further development of 2L-Rap(Q)-hRS7 as a potential therapeutic for various Trop-2–expressing cancers, such as cervical, breast, colon, pancreatic, ovarian, and prostate cancers. Mol Cancer Ther; 9(8); 2276–86. ©2010 AACR.

Purpose: This study examined the delivery of SN-38 to Trop-2–expressing tumors and assessed the constitutive products in the serum, liver, and small intestine in nude mice bearing human tumor xenografts (Capan-1 or NCI-N87) given a single injection of irinotecan (40 mg/kg; ∼0.8 mg/mouse, containing ∼460 μg SN-38 equivalents) or sacituzumab govitecan (IMMU-132), an antibody–drug conjugate composed of a humanized anti-Trop-2 IgG coupled site specifically with an average of 7.6 molecules of SN-38.Experimental Design: At select times, tissues were extracted and concentrations of the products measured by reversed-phase high-performance liquid chromatography (HPLC).Results: In serum, >98% irinotecan cleared within 5 minutes; peak levels of SN-38 and SN-38G (glucuronidated SN-38) were detected in equal amounts at this time, and no longer detected after 6 to 8 hours. IMMU-132 was detected in the serum over 3 days, and at each interval, ≥95% of total SN-38 was bound to the antibody. Intact IMMU-132 cleared with a half-life of 14 hours, which closely reflected the in vitro rate of SN-38 released from the conjugate in mouse serum (i.e., 17.5 hours), whereas the IgG portion of the conjugate cleared with a half-life of 67.1 hours. In vitro and in vivo studies disclosed IgG-bound SN-38 was protected from glucuronidation. Area under the curve (AUC) analysis indicated that IMMU-132 delivers 20-fold to as much as 136-fold more SN-38 to tumors than irinotecan, with tumor:blood ratios favoring IMMU-132 by 20- to 40-fold. Intestinal concentrations of SN-38/SN-38G also were 9-fold lower with IMMU-132.Conclusions: These studies confirm a superior SN-38 tumor delivery by IMMU-132 compared with irinotecan. Clin Cancer Res; 21(22); 5131–8. ©2015 AACR.

Flow cytometric dot plots showing PD-1 expression on CD3+ T cells in PBMCs (left) or CD3+ T cells purified from PBMCs

Purpose: Both PARP inhibitors (PARPi) and sacituzumab govitecan (IMMU-132) are currently under clinical evaluation in triple-negative breast cancer (TNBC). We sought to investigate the combined DNA-damaging effects of the topoisomerase I (Topo I)–inhibitory activity of IMMU-132 with PARPi disruption of DNA repair in TNBC.Experimental Design: In vitro, human TNBC cell lines were incubated with IMMU-132 and various PARPi (olaparib, rucaparib, or talazoparib) to determine the effect on growth, double-stranded DNA (dsDNA) breaks, and cell-cycle arrest. Mice bearing BRCA1/2-mutated or –wild-type human TNBC tumor xenografts were treated with the combination of IMMU-132 and PARPi (olaparib or talazoparib). Study survival endpoint was tumor progression to >1.0 cm3 and tolerability assessed by hematologic changes.Results: Combining IMMU-132 in TNBC with all three different PARPi results in synergistic growth inhibition, increased dsDNA breaks, and accumulation of cells in the S-phase of the cell cycle, regardless of BRCA1/2 status. A combination of IMMU-132 plus olaparib or talazoparib produces significantly improved antitumor effects and delay in time-to-tumor progression compared with monotherapy in mice bearing BRCA1/2-mutated HCC1806 TNBC tumors. Furthermore, in mice bearing BRCA1/2–wild-type tumors (MDA-MB-468 or MDA-MB-231), the combination of IMMU-132 plus olaparib imparts a significant antitumor effect and survival benefit above that achieved with monotherapy. Most importantly, this combination was well tolerated, with no substantial changes in hematologic parameters.Conclusions: These data demonstrate the added benefit of combining Topo I inhibition mediated by IMMU-132 with synthetic lethality provided by PARPi in TNBC, regardless of BRCA1/2 status, thus supporting the rationale for such a combination clinically. Clin Cancer Res; 23(13); 3405–15. ©2017 AACR.

Evaluation of the procedure used to quantitate the constitutive products derived from irinotecan or IMMU-132.

Supplementary Tables

The DOCK-AND-LOCK (DNL) method is a platform technology that combines recombinant engineering and site-specific conjugation to create multispecific, multivalent antibodies of defined composition with retained bioactivity. We have applied DNL to generate a novel class of trivalent bispecific antibodies (bsAb), each comprising an anti-CD3 scFv covalently conjugated to a stabilized dimer of different antitumor Fabs. Here, we report the further characterization of two such constructs, (E1)-3s and (14)-3s, which activate T cells and target Trop-2– and CEACAM5-expressing cancer cells, respectively. (E1)-3s and (14)-3s, in the presence of human T cells, killed target cells grown as monolayers at subnanomolar concentrations, with a similar potency observed for drug-resistant cells. Antitumor efficacy was demonstrated for (E1)-3s coadministered with human peripheral blood mononuclear cells (PBMC) in NOD/SCID mice harboring xenografts of MDA-MB-231, a triple-negative breast cancer line constitutively expressing Trop-2 and PD-L1. Growth inhibition was observed following treatment with (E1)-3s or (14)-3s combined with human PBMC in 3D spheroids generated from target cell lines to mimic the in vivo behavior and microenvironment of these tumors. Moreover, addition of an antagonistic anti–PD-1 antibody increased cell death in 3D spheroids and extended survival of MDA-MB-231-bearing mice. These preclinical results emphasize the potential of combining T-cell–redirecting bsAbs with antagonists or agonists that mitigate T-cell inhibition within the tumor microenvironment to improve immunotherapy of solid cancers in patients. They also support the use of 3D spheroids as a predictive alternative to in vivo models for evaluating T-cell functions. Cancer Res; 77(19); 5384–94. ©2017 AACR.

Upregulation of PD-L1on HCC1954 cells by IFN-gamma.

Supplementary Data from Ranpirnase (Frog RNase) Targeted with a Humanized, Internalizing, Anti–Trop-2 Antibody Has Potent Cytotoxicity against Diverse Epithelial Cancer Cells

Combined file of Table S1 thru S4. Table S1. Blockade of PD-1 binding to PD-L1 on MDA-MB-231 by anti-PD-1. Table S2. Surface expression of CEACAM5 and Trop-2 on selective cell lines. Table S3. Expression of Trop-2 and PD-L1 on MDA-MB-231 and its Trop-2-transfected sublines, including the IC50 of (E1)-3s determined with T cells purified from PBMCs of the same donor. Table S4. Effect of cPD-1 on IC50/EC50 of (E1)-3s to kill MDA-MB-231 or MDA-MB-231-S120 with redirected T cells.

Concentrations of constitutive products in the serum from animals given irinotecan or IMMU-132 in nude mice bearing Capan-1 from 2 separate studies.

In vitro stability of IMMU-132 in mouse serum and measurement of IMMU-132 clearance from mouse serum, with PK parameters.

Effect of cPD-1 and T cells purified from PBMCs on single spheroids of MDA-MB-231 stimulated (A) or not (B) with IFN-gamma in the presence and absence of (E1)-3s

Purpose:Neuroendocrine prostate cancer (NEPC) is an aggressive form of castration-resistant prostate cancer (CRPC) for which effective therapies are lacking. We previously identified carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) as a promising NEPC cell surface antigen. Here we investigated the scope of CEACAM5 expression in end-stage prostate cancer, the basis for CEACAM5 enrichment in NEPC, and the therapeutic potential of the CEACAM5 antibody–drug conjugate labetuzumab govitecan in prostate cancer.Experimental Design:The expression of CEACAM5 and other clinically relevant antigens was characterized by multiplex immunofluorescence of a tissue microarray comprising metastatic tumors from 34 lethal metastatic CRPC (mCRPC) cases. A genetically defined neuroendocrine transdifferentiation assay of prostate cancer was developed to evaluate mechanisms of CEACAM5 regulation in NEPC. The specificity and efficacy of labetuzumab govitecan was determined in CEACAM5+ prostate cancer cell lines and patient-derived xenografts models.Results:CEACAM5 expression was enriched in NEPC compared with other mCRPC subtypes and minimally overlapped with prostate-specific membrane antigen, prostate stem cell antigen, and trophoblast cell surface antigen 2 expression. We focused on a correlation between the expression of the pioneer transcription factor ASCL1 and CEACAM5 to determine that ASCL1 can drive neuroendocrine reprogramming of prostate cancer which is associated with increased chromatin accessibility of the CEACAM5 core promoter and CEACAM5 expression. Labetuzumab govitecan induced DNA damage in CEACAM5+ prostate cancer cell lines and marked antitumor responses in CEACAM5+ CRPC xenograft models including chemotherapy-resistant NEPC.Conclusions:Our findings provide insights into the scope and regulation of CEACAM5 expression in prostate cancer and strong support for clinical studies of labetuzumab govitecan for NEPC.

Figure S4. Concentrations of products in the liver of mice (N = 3) given irinotecan or IMMU-132 determined in 2 separate studies.

Expression of PD-L1 on MDA-MB-231, BxPC-3 and NCI-M87, as determined by flow cytometry.

T cells purified from thawed. cryopreserved PBMCs (lot 032417) induced killing of HT-29 (A) or LS 174T (B) spheroids in the presence of (14)-3s (100 pM).

Supplementary Figures and Supplementary Materials and Methods

Combined file of Fig.S1 thru Fig.S5 - Fig. S1. Biochemical characterization of 5G9.G1.B11. Fig. S2. Binding of 5G9.G1.B11 to native PD-1. Fig. S3. Blocking activities of 5G9.G1.B11. Fig. S4. Biochemical characterization of cPD-1. Fig. S5. Binding of cPD-1 to SpESF-X10-2D1 cells transfected to overexpress human PD-1.

Supplementary Figures S1-S2; Supplementary Materials and Methods; Supplementary Tables S1-S2.

Supplementary Materials, Figures 1-7, Table 1 from Novel Designs of Multivalent Anti-CD20 Humanized Antibodies as Improved Lymphoma Therapeutics

Supplementary Figure 2 from A Novel Bispecific, Trivalent Antibody Construct for Targeting Pancreatic Carcinoma

Preclinical and clinical studies have demonstrated the application of radiolabeled mAb-PAM4 for nuclear imaging and radioimmunotherapy of pancreatic carcinoma. We have now examined the ability of a novel PAM4-based, bispecific monoclonal antibody (mAb) construct, TF10, to pretarget a radiolabeled peptide for improved imaging and therapy. TF10 is a humanized, bispecific mAb, divalent for mAb-PAM4 and monovalent for mAb-679, reactive against the histamine-succinyl-glycine hapten. Biodistribution studies and nuclear imaging of the radiolabeled TF10 and/or TF10-pretargeted hapten-peptide (IMP-288) were conducted in nude mice bearing CaPan1 human pancreatic cancer xenografts. 125I-TF10 cleared rapidly from the blood, with levels decreasing to 111In-IMP-288 was administered 16 hours after TF10. At 3 hours postadministration of radiolabeled peptide, imaging showed intense uptake within the tumors and no evidence of accretion in any normal tissue. No targeting was observed in animals given only the 111In-peptide. Tumor uptake of the TF10-pretargeted 111In-IMP-288 was 24.3 ± 1.7% ID/g, whereas for 111In-IMP-288 alone it was only 0.12 ± 0.002% ID/g at 16 hours. Tumor/blood ratios were significantly greater for the pretargeting group (∼1,000:1 at 3 hours) compared with 111In-PAM4-IgG (∼5:1 at 24 hours; P < 0.0003). Radiation dose estimates suggested that TF10/90Y-peptide pretargeting would provide a greater antitumor effect than 90Y-PAM4-IgG. Thus, the results suggest that TF10 pretargeting may provide improved imaging for early detection, diagnosis, and treatment of pancreatic cancer as compared with directly radiolabeled PAM4-IgG. [Cancer Res 2008;68(12):4819–26]

Supplementary Figure 1 from A Novel Bispecific, Trivalent Antibody Construct for Targeting Pancreatic Carcinoma

In April 2019, the Italian NGO Cittadinanzattiva, through its international branch Active Citizenship Network (ACN) launched, during the European immunization week, a new project called “European Active Citizens for Vaccination”. The aim was to improve the awareness on the importance of vaccination across Europe: The scientific evidence is clear; vaccination is an essential public health tool and helps to guarantee our fundamental rights as European citizens. ACN realized a social media communication campaign supporting and spreading awareness on the topic of life-long vaccination, videos were made in all the national languages of the involved countries (Italy, Hungary, Poland, Ireland and Spain) and then produced, shared and customized for each country. Moreover, an informative leaflet in a different language was produced. Civic consultations on the National Immunization Plan were held in Poland, Hungary and Spain. This article describes the main results of the focus group held in Spain on the topic of vaccination and on its related policies. The full report has been published in the Report entitled “European Active Citizens for Vaccination: focus on Spain (2019 - 2020)” edited by Cittadinanzattiva APS.

Sacituzumab govitecan (SG) is an antibody-drug conjugate composed of a humanized anti-Trop-2 IgG antibody conjugated via a hydrolysable linker to SN-38, the topoisomerase I-inhibitory active component of irinotecan. We investigated whether Trop-2-expression and homologous recombination repair (HRR) of SN-38-mediated double-strand DNA (dsDNA) breaks play a role in the sensitivity of triple-negative breast cancer (TNBC) to SG. Activation of HRR pathways, as evidenced by Rad51 expression, was assessed in SG-sensitive cell lines with low and moderate Trop-2-expression (SK-MES-1 squamous cell lung carcinoma and HCC1806 TNBC, respectively), compared to a low Trop-2-expressing, less SG-sensitive TNBC cell line (MDA-MB-231). Further, two Trop-2-transfectants of MDA-MB-231, C13 and C39 (4- and 25-fold higher Trop-2, respectively), were treated in mice with SG to determine whether increasing Trop-2 expression improves SG efficacy. SG mediated >2-fold increase in Rad51 in MDA-MB-231 but had no effect in SK-MES-1 or HCC1806, resulting in lower levels of dsDNA breaks in MDA-MB-231. SG and saline produced similar effects in parental MDA-MB-231 tumor-bearing mice (median survival time (MST) = 21d and 19.5d, respectively). However, in mice bearing higher Trop-2-expressing C13 and C39 tumors after Trop-2 transfection, SG provided a significant survival benefit, even compared to irinotecan (MST = 97d vs. 35d for C13, and 81d vs. 28d for C39, respectively; P < 0.0007). These results suggest that SG could provide better clinical benefit than irinotecan in patients with HRR-proficient tumors expressing high levels of Trop-2, as well as to patients with HRR-deficient tumors expressing low/moderate levels of Trop-2.

Antibody–drug conjugates (ADC) are a rapidly growing class of targeted cancer treatments, but the field has experienced significant challenges from their complex design. This study examined the multiscale distribution of sacituzumab govitecan (SG; Trodelvy), a recently clinically approved ADC, to clarify the mechanism(s) of efficacy given its unique design strategy. We employed a multiscale quantitative pharmacokinetic approach, including near-infrared fluorescence imaging, single-cell flow cytometry measurements, payload distribution via γH2AX pharmacodynamic staining, and a novel dual-labeled fluorescent technique to track the ADC and payload in a high trophoblast cell-surface antigen 2 expression xenograft model of gastric cancer (NCI-N87). We found that rapid release of the SN-38 payload from the hydrolysable linker inside cells imparts more DNA damage in vitro and in vivo than an ADC with a more stable enzyme cleavable linker. With SG, little to no extracellular payload release in the tumor was observed using a dual-labeled fluorescence technique, although bystander effects were detected. The high dosing regimen allowed the clinical dose to reach the majority of cancer cells, which has been linked to improved efficacy. In addition, the impact of multiple doses (day 1 and day 8) of a 21-day cycle was found to further improve tissue penetration despite not changing tumor uptake [percent injected dose per gram (%ID/g)] of the ADC. These results show increased ADC efficacy with SG can be attributed to efficient tumor penetration and intracellular linker cleavage after ADC internalization. This quantitative approach to study multiscale delivery can be used to inform the design of next-generation ADCs and prodrugs for other targets.

The ASTRI (Astrofisica con Specchi a Tecnologia Replicante Italiana) Mini-Array will be composed of nine imaging atmospheric Cherenkov telescopes at the Observatorio del Teide site. The array will be best suited for astrophysical observations in the 0.3-200 TeV range with an angular resolution of few arc-minutes and an energy resolution of 10-15\%. A core-science programme in the first four years will be devoted to a limited number of key targets, addressing the most important open scientific questions in the very-high energy domain. At the same time, thanks to a wide field of view of about 10 degrees, ASTRI Mini-Array will observe many additional field sources, which will constitute the basis for the long-term observatory programme that will eventually cover all the accessible sky. In this paper, we review different astrophysical Galactic environments, e.g. pulsar wind nebulae, supernova remnants, and gamma-ray binaries, and show the results from a set of ASTRI Mini-Array simulations of some of these field sources made to highlight the expected performance of the array (even at large offset angles) and the important additional observatory science that will complement the core-science program., Comment: Accepted for publication in Journal of High-Energy Astrophysics