scholarly journals Subcutaneous administration of neutralizing antibodies to endothelial monocyte-activating protein II attenuates cigarette smoke-induced lung injury in mice

2019 ◽  
Vol 316 (3) ◽  
pp. L558-L566 ◽  
Author(s):  
Kengo Koike ◽  
Erica L. Beatman ◽  
Kelly S. Schweitzer ◽  
Matthew J. Justice ◽  
Andrew M. Mikosz ◽  
...  
Keyword(s):  
Cigarette Smoke ◽  
Lung Inflammation ◽  
Neutralizing Antibodies ◽  
Cell Injury ◽  
Therapeutic Potential ◽  
Mammalian Target Of Rapamycin ◽  
Subcutaneous Administration ◽  
Neutralizing Antibody ◽  
Treatment Modalities ◽  
Antibody Treatment

Proapoptotic and monocyte chemotactic endothelial monocyte-activating protein 2 (EMAPII) is released extracellularly during cigarette smoke (CS) exposure. We have previously demonstrated that, when administered intratracheally during chronic CS exposures, neutralizing rat antibodies to EMAPII inhibited endothelial cell apoptosis and lung inflammation and reduced airspace enlargement in mice (DBA/2J strain). Here we report further preclinical evaluation of EMAPII targeting using rat anti-EMAPII antibodies via either nebulization or subcutaneous injection. Both treatment modalities efficiently ameliorated emphysema-like disease in two different strains of CS-exposed mice, DBA/2J and C57BL/6. Of relevance for clinical applicability, this treatment showed therapeutic and even curative potential when administered either during or following CS-induced emphysema development, respectively. In addition, a fully humanized neutralizing anti-EMAPII antibody administered subcutaneously to mice during CS exposure retained anti-apoptotic and anti-inflammatory effects similar to that of the parent rat antibody. Furthermore, humanized anti-EMAPII antibody treatment attenuated CS-induced autophagy and restored mammalian target of rapamycin signaling in the lungs of mice, despite ongoing CS exposure. Together, our results demonstrate that EMAPII secretion is involved in CS-induced lung inflammation and cell injury, including apoptosis and autophagy, and that a humanized EMAPII neutralizing antibody may have therapeutic potential in emphysema.

scholarly journals The Fc-mediated effector functions of a potent SARS-CoV-2 neutralizing antibody, SC31, isolated from an early convalescent COVID-19 patient, are essential for the optimal therapeutic efficacy of the antibody

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0253487
Author(s):  
Conrad E. Z. Chan ◽  
Shirley G. K. Seah ◽  
De Hoe Chye ◽  
Shane Massey ◽  
Maricela Torres ◽  
...  
Keyword(s):  
Therapeutic Efficacy ◽  
Neutralizing Antibodies ◽  
Inflammatory Responses ◽  
Therapeutic Potential ◽  
Rhesus Macaques ◽  
Neutralizing Antibody ◽  
Effector Functions ◽  
Viral Loads ◽  
Therapeutic Doses ◽  
Dose Dependent

Although SARS-CoV-2-neutralizing antibodies are promising therapeutics against COVID-19, little is known about their mechanism(s) of action or effective dosing windows. We report the generation and development of SC31, a potent SARS-CoV-2 neutralizing antibody, isolated from a convalescent patient. Antibody-mediated neutralization occurs via an epitope within the receptor-binding domain of the SARS-CoV-2 Spike protein. SC31 exhibited potent anti-SARS-CoV-2 activities in multiple animal models. In SARS-CoV-2 infected K18-human ACE2 transgenic mice, treatment with SC31 greatly reduced viral loads and attenuated pro-inflammatory responses linked to the severity of COVID-19. Importantly, a comparison of the efficacies of SC31 and its Fc-null LALA variant revealed that the optimal therapeutic efficacy of SC31 requires Fc-mediated effector functions that promote IFNγ-driven anti-viral immune responses, in addition to its neutralization ability. A dose-dependent efficacy of SC31 was observed down to 5mg/kg when administered before viral-induced lung inflammatory responses. In addition, antibody-dependent enhancement was not observed even when infected mice were treated with SC31 at sub-therapeutic doses. In SARS-CoV-2-infected hamsters, SC31 treatment significantly prevented weight loss, reduced viral loads, and attenuated the histopathology of the lungs. In rhesus macaques, the therapeutic potential of SC31 was evidenced through the reduction of viral loads in both upper and lower respiratory tracts to undetectable levels. Together, the results of our preclinical studies demonstrated the therapeutic efficacy of SC31 in three different models and its potential as a COVID-19 therapeutic candidate.

scholarly journals Matrine reduces cigarette smoke-induced airway neutrophilic inflammation by enhancing neutrophil apoptosis

2019 ◽  
Vol 133 (4) ◽  
pp. 551-564 ◽  
Author(s):  
Xuhua Yu ◽  
Huei Jiunn Seow ◽  
Hao Wang ◽  
Desiree Anthony ◽  
Steven Bozinovski ◽  
...  
Keyword(s):  
Cigarette Smoke ◽  
Lung Inflammation ◽  
Therapeutic Potential ◽  
Proteolytic Enzymes ◽  
Ex Vivo ◽  
Lavage Fluid ◽  
Airflow Limitation ◽  
Chronic Obstructive ◽  
Neutrophilic Inflammation ◽  
Anti Inflammatory

AbstractChronic Obstructive Pulmonary Disease (COPD) is a major incurable global health burden and will become the third largest cause of death in the world by 2030. It is well established that an exaggerated inflammatory and oxidative stress response to cigarette smoke (CS) leads to, emphysema, small airway fibrosis, mucus hypersecretion, and progressive airflow limitation. Current treatments have limited efficacy in inhibiting chronic inflammation and consequently do not reverse the pathology that initiates and drives the long-term progression of disease. In particular, there are no effective therapeutics that target neutrophilic inflammation in COPD, which is known to cause tissue damage by degranulation of a suite of proteolytic enzymes including neutrophil elastase (NE). Matrine, an alkaloid compound extracted from Sophora flavescens Ait, has well known anti-inflammatory activity. Therefore, the aim of the present study was to investigate whether matrine could inhibit CS-induced lung inflammation in mice. Matrine significantly reduced CS-induced bronchoalveolar lavage fluid (BALF) neutrophilia and NE activity in mice. The reduction in BALF neutrophils in CS-exposed mice by matrine was not due to reductions in pro-neutrophil cytokines/chemokines, but rather matrine’s ability to cause apoptosis of neutrophils, which we demonstrated ex vivo. Thus, our data suggest that matrine has anti-inflammatory actions that could be of therapeutic potential in treating CS-induced lung inflammation observed in COPD.

scholarly journals Characterization of Co-Formulated High-Concentration Broadly Neutralizing Anti-HIV-1 Monoclonal Antibodies for Subcutaneous Administration

Antibodies ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 36
Author(s):  
Vaneet K. Sharma ◽  
Bijay Misra ◽  
Kevin T. McManus ◽  
Sreenivas Avula ◽  
Kaliappanadar Nellaiappan ◽  
...  
Keyword(s):  
Neutralizing Antibodies ◽  
Clinical Investigation ◽  
Total Concentration ◽  
Subcutaneous Administration ◽  
Analytical Techniques ◽  
Neutralizing Antibody ◽  
High Concentration ◽  
Anti Hiv ◽  
Hiv 1

The discovery of numerous potent and broad neutralizing antibodies (bNAbs) against Human Immunodeficiency Virus type 1 (HIV-1) envelope glycoprotein has invigorated the potential of using them as an effective preventative and therapeutic agent. The majority of the anti-HIV-1 antibodies, currently under clinical investigation, are formulated singly for intra-venous (IV) infusion. However, due to the high degree of genetic variability in the case of HIV-1, a single broad neutralizing antibody will likely not be sufficient to protect against the broad range of viral isolates. To that end, delivery of two or more co-formulated bnAbs against HIV-1 in a single subcutaneous (SC) injection is highly desired. We, therefore, co-formulated two anti-HIV bnAbs, 3BNC117-LS and 10-1074-LS, to a total concentration of 150 mg/mL for SC administration and analyzed them using a panel of analytical techniques. Chromatographic based methods, such as RP-HPLC, CEX-HPLC, SEC-HPLC, were developed to ensure separation and detection of each antibody in the co-formulated sample. In addition, we used a panel of diverse pseudoviruses to detect the functionality of individual antibodies in the co-formulation. We also used these methods to test the stability of the co-formulated antibodies and believe that such an approach can support future efforts towards the formulation and characterization of multiple high-concentration antibodies for SC delivery.

scholarly journals Human Immunodeficiency Virus Type 1 Escape from Cyclotriazadisulfonamide-Induced CD4-Targeted Entry Inhibition Is Associated with Increased Neutralizing Antibody Susceptibility

2009 ◽  
Vol 83 (18) ◽  
pp. 9577-9583 ◽  
Author(s):  
Kurt Vermeire ◽  
Kristel Van Laethem ◽  
Wouter Janssens ◽  
Thomas W. Bell ◽  
Dominique Schols
Keyword(s):  
Human Immunodeficiency Virus ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Neutralizing Antibodies ◽  
Neutralizing Antibody ◽  
Receptor Expression ◽  
Antibody Treatment ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Continuous specific downmodulation of CD4 receptor expression in T lymphocytes by the small molecule cyclotriazadisulfonamide (CADA) selected for the CADA-resistant human immunodeficiency virus type 1 (HIV-1) NL4.3 virus containing unique mutations in the C4 and V5 regions of gp120, likely stabilizing the CD4-binding conformation. The amino acid changes in Env were associated with decreased susceptibility to anti-CD4 monoclonal antibody treatment of the cells and with higher susceptibility of the virus to soluble CD4. In addition, the acquired ability of a CADA-resistant virus to infect cells with low CD4 expression was associated with an increased susceptibility of the virus to neutralizing antibodies from sera of several HIV-1-infected patients.

scholarly journals Neutralizing antibody-independent immunity to SARS-CoV-2 in hamsters and hACE-2 transgenic mice immunized with a RBD/Nucleocapsid fusion protein

2021 ◽  
Author(s):  
Julia Castro ◽  
Marcilio Fumagalli ◽  
Natalia Hojo-Souza ◽  
Patrick Azevedo ◽  
Natalia Salazar ◽  
...  
Keyword(s):  
T Cell ◽  
Transgenic Mice ◽  
Lung Inflammation ◽  
Neutralizing Antibodies ◽  
Chimeric Protein ◽  
Neutralizing Antibody ◽  
Receptor Binding Domain ◽  
Wild Type ◽  
N Protein ◽  
Cell Responses

The nucleocapsid (N) and the receptor binding domain (RBD) of the Spike (S) proteins elicit robust antibody and T cell responses either in vaccinated or COVID-19 convalescent individuals. We generated a chimeric protein that comprises the sequences of RBD from S and N antigens (SpiN). SpiN was highly immunogenic and elicited a strong IFNγ response from T cells and high levels of antibodies to the inactivated virus, but no neutralizing antibodies. Importantly, hamsters and the human Angiotensin Convertase Enzyme-2-transgenic mice immunized with SpiN were highly resistant to challenge with the wild type SARS-CoV-2, as indicated by viral load, clinical outcome, lung inflammation and lethality. Thus, the N protein should be considered to induce T-cell-based immunity to improve SARS-CoV-2 vaccines, and eventually to circumvent the immune scape by variants.

scholarly journals Pre-existing neutralizing antibodies prevent CD8 T cell-mediated immunopathology following respiratory syncytial virus infection

2019 ◽  
Vol 13 (3) ◽  
pp. 507-517 ◽  
Author(s):  
Megan E. Schmidt ◽  
David K. Meyerholz ◽  
Steven M. Varga
Keyword(s):  
T Cell ◽  
Neutralizing Antibodies ◽  
Neutralizing Antibody ◽  
Cd8 T Cell ◽  
Antibody Treatment ◽  
Memory Cd8 T Cells ◽  
Rsv Infection ◽  
Ifn Γ ◽  
Memory Cd8 T Cell ◽  
Syncytial Virus

AbstractDespite being a leading cause of severe respiratory disease, there remains no licensed respiratory syncytial virus (RSV) vaccine. Neutralizing antibodies reduce the severity of RSV-associated disease, but are not sufficient for preventing reinfection. In contrast, the role of memory CD8 T cells in protecting against a secondary RSV infection is less established. We recently demonstrated that high-magnitude memory CD8 T cells efficiently reduced lung viral titers following RSV infection, but induced fatal immunopathology that was mediated by IFN-γ. To evaluate the ability of RSV-specific neutralizing antibodies to prevent memory CD8 T cell-mediated immunopathology, mice with high-magnitude memory CD8 T cell responses were treated with neutralizing antibodies prior to RSV challenge. Neutralizing antibody treatment significantly reduced morbidity and prevented mortality following RSV challenge compared with IgG-treated controls. Neutralizing antibody treatment restricted early virus replication, which caused a substantial reduction in memory CD8 T cell activation and IFN-γ production, directly resulting in survival. In contrast, therapeutic neutralizing antibody administration did not impact morbidity, mortality, or IFN-γ levels, despite significantly reducing lung viral titers. Therefore, only pre-existing neutralizing antibodies prevent memory CD8 T cell-mediated immunopathology following RSV infection. Overall, our results have important implications for the development of future RSV vaccines.

scholarly journals Influenza A Virus Antibodies with Antibody-Dependent Cellular Cytotoxicity Function

Viruses ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 276 ◽  
Author(s):  
Rongyuan Gao ◽  
Zizhang Sheng ◽  
Chithra C. Sreenivasan ◽  
Dan Wang ◽  
Feng Li
Keyword(s):  
Neutralizing Antibodies ◽  
Influenza A ◽  
Therapeutic Potential ◽  
Influenza Infection ◽  
Neutralizing Antibody ◽  
Health Concern ◽  
Cellular Cytotoxicity ◽  
Antibody Dependent Cellular Cytotoxicity ◽  
Effector Functions ◽  
Recent Advances

Influenza causes millions of cases of hospitalizations annually and remains a public health concern on a global scale. Vaccines are developed and have proven to be the most effective countermeasures against influenza infection. Their efficacy has been largely evaluated by hemagglutinin inhibition (HI) titers exhibited by vaccine-induced neutralizing antibodies, which correlate fairly well with vaccine-conferred protection. Contrarily, non-neutralizing antibodies and their therapeutic potential are less well defined, yet, recent advances in anti-influenza antibody research indicate that non-neutralizing Fc-effector activities, especially antibody-dependent cellular cytotoxicity (ADCC), also serve as a critical mechanism in antibody-mediated anti-influenza host response. Monoclonal antibodies (mAbs) with Fc-effector activities have the potential for prophylactic and therapeutic treatment of influenza infection. Inducing mAbs mediated Fc-effector functions could be a complementary or alternative approach to the existing neutralizing antibody-based prevention and therapy. This review mainly discusses recent advances in Fc-effector functions, especially ADCC and their potential role in influenza countermeasures. Considering the complexity of anti-influenza approaches, future vaccines may need a cocktail of immunogens in order to elicit antibodies with broad-spectrum protection via multiple protective mechanisms.

scholarly journals Predicting in vivo escape dynamics of HIV-1 from a broadly neutralizing antibody

2021 ◽  
Vol 118 (30) ◽  
pp. e2104651118
Author(s):  
Matthijs Meijers ◽  
Kanika Vanshylla ◽  
Henning Gruell ◽  
Florian Klein ◽  
Michael Lässig
Keyword(s):  
Viral Load ◽  
Neutralizing Antibodies ◽  
Neutralizing Antibody ◽  
Broadly Neutralizing Antibodies ◽  
Antibody Treatment ◽  
Trade Off ◽  
Escape Dynamics ◽  
Resistance Evolution ◽  
Hiv 1

Broadly neutralizing antibodies are promising candidates for treatment and prevention of HIV-1 infections. Such antibodies can temporarily suppress viral load in infected individuals; however, the virus often rebounds by escape mutants that have evolved resistance. In this paper, we map a fitness model of HIV-1 interacting with broadly neutralizing antibodies using in vivo data from a recent clinical trial. We identify two fitness factors, antibody dosage and viral load, that determine viral reproduction rates reproducibly across different hosts. The model successfully predicts the escape dynamics of HIV-1 in the course of an antibody treatment, including a characteristic frequency turnover between sensitive and resistant strains. This turnover is governed by a dosage-dependent fitness ranking, resulting from an evolutionary trade-off between antibody resistance and its collateral cost in drug-free growth. Our analysis suggests resistance–cost trade-off curves as a measure of antibody performance in the presence of resistance evolution.

scholarly journals Characterization of neutralizing antibodies from a SARS-CoV-2 infected individual

2020 ◽  
Author(s):  
Emilie Seydoux ◽  
Leah J. Homad ◽  
Anna J. MacCamy ◽  
K. Rachael Parks ◽  
Nicholas K. Hurlburt ◽  
...  
Keyword(s):  
B Cells ◽  
B Cell ◽  
Neutralizing Antibodies ◽  
Therapeutic Potential ◽  
Infected Individual ◽  
Neutralizing Antibody ◽  
Viral Envelope ◽  
List Type ◽  
Cell Lineages

ABSTRACTB cells specific for the SARS-CoV-2 S envelope glycoprotein spike were isolated from a COVID-19-infected subject using a stabilized spike-derived ectodomain (S2P) twenty-one days post-infection. Forty-four S2P-specific monoclonal antibodies were generated, three of which bound to the receptor binding domain (RBD). The antibodies were minimally mutated from germline and were derived from different B cell lineages. Only two antibodies displayed neutralizing activity against SARS-CoV-2 pseudo-virus. The most potent antibody bound the RBD in a manner that prevented binding to the ACE2 receptor, while the other bound outside the RBD. Our study indicates that the majority of antibodies against the viral envelope spike that were generated during the first weeks of COVID-19 infection are non-neutralizing and target epitopes outside the RBD. Antibodies that disrupt the SARS-CoV-2 spike-ACE2 interaction can potently neutralize the virus without undergoing extensive maturation. Such antibodies have potential preventive/therapeutic potential and can serve as templates for vaccine-design.IN BRIEFSARS-CoV-2 infection leads to expansion of diverse B cells clones against the viral spike glycoprotein (S). The antibodies bind S with high affinity despite being minimally mutated. Thus, the development of neutralizing antibody responses by vaccination will require the activation of certain naïve B cells without requiring extensive somatic mutation.HighlightsAnalysis of early B cell response to SARS-CoV-2 spike proteinMost antibodies target non-neutralizing epitopesPotent neutralizing mAb blocks the interaction of the S protein with ACE2Neutralizing antibodies are minimally mutated

G-CSF partially mediates bone loss induced by Staphylococcus aureus infection in mice

2019 ◽  
Vol 133 (12) ◽  
pp. 1297-1308 ◽  
Author(s):  
Yilong Hou ◽  
Hanjun Qin ◽  
Nan Jiang ◽  
Guanqiao Liu ◽  
Hangtian Wu ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Bone Loss ◽  
Mrna Expression ◽  
Therapeutic Potential ◽  
Neutralizing Antibody ◽  
Inflammatory Factors ◽  
Enzyme Linked Immunosorbent Assay ◽  
Orthopedic Treatment ◽  
Antibody Treatment ◽  
Aureus Infection

AbstractBone loss in Staphylococcus aureus (S. aureus) osteomyelitis poses a serious challenge to orthopedic treatment. The present study aimed to elucidate how S. aureus infection in bone might induce bone loss. The C57BL/6 mice were injected with S. aureus (106 CFU/ml, 100 μl) or with the same amount of vehicle (control) via the tail vein. Microcomputed tomography (microCT) analysis showed bone loss progressing from week 1 to week 5 after infection, accompanied by a decreased number of osteocalcin-positive stained osteoblasts and the suppressed mRNA expression of Runx2 and osteocalcin. Transcriptome profiles of GSE30119 were downloaded and analyzed to determine the differences in expression of inflammatory factors between patients with S. aureus infected osteomyelitis and healthy controls, the data showed significantly higher mRNA expression of granulocyte colony-stimulating factor (G-CSF) in the whole blood from patients with S. aureus infection. Enzyme-linked immunosorbent assay (ELISA) analysis confirmed an increased level of G-CSF in the bone marrow and serum from S. aureus infected mice, which might have been due to the increased amount of F4/80+ macrophages. Interestingly, G-CSF neutralizing antibody treatment significantly rescued the bone loss after S. aureus infection, as evidenced by its roles in improving BV/TV and preserving osteocalcin- and osterix-positive stained cells. Importantly, we found that G-CSF level was significantly up-regulated in the serum from osteomyelitis patients infected by S. aureus. Together, S. aureus infection might suppress the function of osteoblastic cells and induce progressive bone loss by up-regulating the level G-CSF, suggesting a therapeutic potential for G-CSF neutralization in combating bone loss in S. aureus osteomyelitis.

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