In vivo biodistribution and lifetime analysis of cy5.5-conjugated rituximab in mice bearing lymphoid tumor xenograft using time-domain near-infrared optical imaging

Rituximab is a chimeric monoclonal antibody directed against human CD20 antigen, which is expressed on B-cell lymphocytes and on the majority of B-cell lymphoid malignancies. Herein we report the conjugate of rituximab with the near-infrared (NIR) fluorophore Cy5.5 (RI-Cy5.5) as a tool for in vitro, in vivo, and ex vivo NIR time-domain (TD) optical imaging. In vitro, RI-Cy5.5 retained biologic activity and led to elevated cell-associated fluorescence on tumor cells. In vivo, TD optical imaging analysis of RI-Cy5.5 injected into lymphoma-bearing mice revealed a slow tumor uptake and a specific long-lasting persistence of the probe within the tumor. Biodistribution studies after intraperitoneal and endovenous administration were undertaken to evaluate differences in the tumor uptake. RI-Cy5.5 concentration in the organs after intraperitoneal injection was not as high as after endovenous injection. Ex vivo analysis of biologic tissues and organs by both TD optical imaging and immunohistochemistry confirmed the probe distribution, as demonstrated by imaging experiment in vivo, showing that RI-Cy5.5 selectively accumulated in the tumor tissue and major excretion organs. In summary, the study indicates that NIR TD optical imaging is a powerful tool for rituximab-targeting investigation, furthering understanding of its administration outcome in lymphoma treatment

C7 is expressed on endothelial cells as a trap for the assembling terminal complement complex and may exert anti-inflammatory function

We describe a novel localization of C7 as a membrane-bound molecule on endothelial cells (ECs). Data obtained by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Western blot analysis, Northern blot analysis, and mass spectrometry revealed that membrane- associated C7 (mC7) was indistinguish-able from soluble C7 and was associated with vimentin on the cell surface. mC7 interacted with the other late complement components to form membrane-bound TCC (mTCC). Unlike the soluble SC5b-9, mTCC failed to stimulate ECs to express adhesion molecules, to secrete IL-8, and to induce albumin leakage through a monolayer of ECs, and more importantly protected ECs from the proinflammatory effect of SC5b-9. Our data disclose the possibility of a novel role of mC7 that acts as a trap for the late complement components to control excessive inflammation induced by SC5b-9. \ua9 2009 by The American Society of Hematology

Blood ozonization in patients with mild to moderate COVID-19 pneumonia: a single centre experience

The emerging outbreak of the coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to spread worldwide. We prescribed some promising medication to our patients with mild to moderate pneumonia due to SARS-CoV-2, however such drugs as chloroquine, hydrossichloroquine, azithromycin, antivirals (lopinavir/ritonavir, darunavir/cobicistat) and immunomodulating agents (steroids, tocilizumab) were not confirmed as effective against SARS-CoV2. We, therefore, started to use auto-hemotherapy treated with an oxygen/ozone (O2/O3) gaseous mixture as adjuvant therapy. In Udine University Hospital (Italy) we performed a case\u2013control study involving hospitalized adult patients with confirmed COVID-19 with mild to moderate pneumonia. Clinical presentations are based upon clinical phenotypes identified by the Italian Society of Emergency and Urgency Medicine (SIMEU\u2014Societ\ue0 Italiana di Medicina di Emergenza-Urgenza) and patients that met criteria of phenotypes 2 to 4 were treated with best available therapy (BAT), with or without O3-autohemotherapy. 60 patients were enrolled in the study: 30 patients treated with BAT and O2/O3 mixture, as adjuvant therapy and 30 controls treated with BAT only. In the group treated with O3-autohemotherapy plus BAT, patients were younger but with more severe clinical phenotypes. A decrease of SIMEU clinical phenotypes was observed (2.70 \ub1 0.67 vs. 2.35 \ub1 0.88, p = 0.002) in all patients during hospitalization but this clinical improvement\ua0was statistically significant only in O3-treated patients (2.87 \ub1 0.78 vs. 2.27 \ub1 0.83, p < 0.001), differently to the control group (2.53 \ub1 0.51 vs. 2.43 \ub1 0.93, p = 0.522). No adverse events were observed associated with the application of O2/O3 gaseous mixture. O2/O3 therapy as adjuvant therapy could be useful in mild to moderate pneumonia due to SARS-CoV-2. Randomized prospective study is ongoing [Clinical Trials.gov ID: Z7C2CA5837]

High-throughput assessment of the antibody profile in ovarian cancer ascitic fluids

The identification of effective biomarkers for early diagnosis, prognosis, and response to treatments remains a challenge in ovarian cancer (OC) research. Here, we present an unbiased high-throughput approach to profile ascitic fluid autoantibodies in order to obtain a tumor-specific antigen signature in OC. We first reported the reactivity of immunoglobulins (Igs) purified from OC patient ascites towards two different OC cell lines. Using a discovery set of Igs, we selected tumor-specific antigens from a phage display cDNA library. After biopanning, 700 proteins were expressed as fusion protein and used in protein array to enable large-scale immunoscreening with independent sets of cancer and noncancerous control. Finally, the selected antigens were validated by ELISA. The initial screening identified eight antigenic clones: CREB3, MRPL46, EXOSC10, BCOR, HMGN2, HIP1R, OLFM4, and KIAA1755. These antigens were all validated by ELISA in a study involving ascitic Igs from 153 patients (69 with OC, 34 with other cancers and 50 without cancer), with CREB3 showing the highest sensitivity (86.95%) and specificity (98%). Notably, we were able to identify an association between the tumor-associated (TA) antibody response and the response to a first-line tumor treatment (platinum-based chemotherapy). A stronger association was found by combining three antigens (BCOR, CREB3, and MRLP46) as a single antibody signature. Measurement of an ascitic fluid antibody response to multiple TA antigens may aid in the identification of new prognostic signatures in OC patients and shift attention to new potentially relevant targets

Bispecific antibodies targeting tumor-associated antigens and neutralizing complement regulators increase the efficacy of antibody-based immunotherapy in mice.

The efficacy of antibody-based immunotherapy is due to the activation of apoptosis, the engagement of antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity (CDC). We developed a novel strategy to enhance CDC using bispecific antibodies (bsAbs) that neutralize the C-regulators CD55 and CD59 to enhance C-mediated functions. Two bsAbs (MB20/55 and MB20/59) were designed to recognize CD20 on one side. The other side neutralizes CD55 or CD59. Analysis of CDC revealed that bsAbs could kill 4 to 25 times more cells than anti-CD20 recombinant antibody in cell lines or cells isolated from patients with chronic lymphocytic leukemia. The pharmacokinetics of the bsAbs was evaluated in a human-SCID model of Burkitt lymphoma. The distribution profile of bsAbs mimics the data obtained by studying the pharmacokinetics of anti-CD20 antibodies, showing a peak in the tumor mass 3-4 days after injection. The treatment with bsAbs completely prevented the development of human/SCID lymphoma. The tumor growth was blocked by the activation of the C cascade and by the recruitment of macrophages, PMN and NK cells. This strategy can easily be applied to the other anti-tumor C-fixing antibodies currently used in the clinic or tested in preclinical studies using the same vector with the appropriate modifications

The Inflammatory Feed-Forward Loop Triggered by the Complement Component C3 as a Potential Target in Endometriosis

The complement system is a major component of humoral innate immunity, acting as a first line of defense against microbes via opsonization and lysis of pathogens. However, novel roles of the complement system in inflammatory and immunological processes, including in cancer, are emerging. Endometriosis (EM), a benign disease characterized by ectopic endometrial implants, shows certain unique features of cancer, such as the capacity to invade surrounding tissues, and in severe cases, metastatic properties. A defective immune surveillance against autologous tissue deposited in the peritoneal cavity allows immune escape for endometriotic lesions. There is evidence that the glandular epithelial cells found in endometriotic implants produce and secrete the complement component C3. Here, we show, using immunofluorescence and RT-qPCR, the presence of locally synthesized C3 in the ectopic endometriotic tissue, but not in the eutopic tissue. We generated a murine model of EM via injection of minced uterine tissue from a donor mouse into the peritoneum of recipient mice. The wild type mice showed greater amount of cyst formation in the peritoneum compared to C3 knock-out mice. Peritoneal washings from the wild type mice with EM showed more degranulated mast cells compared to C3 knock-out mice, consistent with higher C3a levels in the peritoneal fluid of EM patients. We provide evidence that C3a participates in an auto-amplifying loop leading to mast cell infiltration and activation, which is pathogenic in EM. Thus, C3 can be considered a marker of EM and its local synthesis can promote the engraftment of the endometriotic cysts

Constitutive psgl-1 correlates with cd30 and tcr pathways and represents a potential target for immunotherapy in anaplastic large t-cell lymphoma

Due to the high expression of P-selectin glycoprotein ligand-1 (PSGL-1) in lymphoprolif-erative disorders and in multiple myeloma, it has been considered as a potential target for humoral immunotherapy, as well as an immune checkpoint inhibitor in T-cells. By investigating the expression of SELPLG in 678 T-and B-cell samples by gene expression profiling (GEP), further supported by tissue microarray and immunohistochemical analysis, we identified anaplastic large T-cell lymphoma (ALCL) as constitutively expressing SELPLG at high levels. Moreover, GEP analysis in CD30+ ALCLs highlighted a positive correlation of SELPLG with TNFRSF8 (CD30-coding gene) and T-cell receptor (TCR)-signaling genes (LCK, LAT, SYK and JUN), suggesting that the common dysreg-ulation of TCR expression in ALCLs may be bypassed by the involvement of PSGL-1 in T-cell activation and survival. Finally, we evaluated the effects elicited by in vitro treatment with two anti-PSGL-1 antibodies (KPL-1 and TB5) on the activation of the complement system and induction of apoptosis in human ALCL cell lines. In conclusion, our data demonstrated that PSGL-1 is specifically enriched in ALCLs, altering cell motility and viability due to its involvement in CD30 and TCR signaling, and it might be considered as a promising candidate for novel immunotherapeutic approaches in ALCLs

Hippocampal Deletion of BDNF Gene Attenuates Gamma Oscillations in Area CA1 by Up-Regulating 5-HT3 Receptor

Background: Pyramidal neurons in the hippocampal area CA3 express high levels of BDNF, but how this BDNF contributes to oscillatory properties of hippocampus is unknown. Methodology/Principal Findings: Here we examined carbachol-induced gamma oscillations in hippocampal slices lacking BDNF gene in the area CA3. The power of oscillations was reduced in the hippocampal area CA1, which coincided with increases in the expression and activity of 5-HT3 receptor. Pharmacological block of this receptor partially restored power of gamma oscillations in slices from KO mice, but had no effect in slices from WT mice. Conclusion/Significance: These data suggest that BDNF facilitates gamma oscillations in the hippocampus by attenuating signaling through 5-HT3 receptor. Thus, BDNF modulates hippocampal oscillations through serotonergic system