Abstract
Objective To determine if mitigating the harmful effects of circulating microvesicle-associated inducible nitric oxide (MV-A iNOS) in vivo increases the survival of challenged mice in three different mouse models of sepsis.
Design The ability of anti-MV-A iNOS monoclonal antibodies (mAbs) to rescue challenged mice was assessed using three different mouse models of sepsis.
Setting The vivarium of a research laboratory
Subjects Balb/c mice
Interventions: Mice were challenged with an LD80 dose of either lipopolysaccharide (LPS / endotoxin), TNFα, or MV-A iNOS and then treated at various times after the challenge with saline as control or with an anti-MV-A iNOS mAb as a potential immunotherapeutic to treat sepsis.
Measurement and Main Results Each group of mice was checked daily for survivors, and Kaplan-Meier survival curves were constructed. Five different murine anti-MV-A iNOS mAbs from our panel of 24 murine anti-MV-A iNOS mAbs (1) were found to rescue some of the challenged mice. All five murine mAbs were used to genetically engineer humanized anti-MV-A iNOS mAbs by inserting the murine complementarity-determining regions (CDRs) into a human IgG1,kappa scaffold and expressing the humanized mAbs in CHO cells. Three humanized anti-MV-A iNOS mAbs were effective at rescuing mice from sepsis in three different animal models of sepsis. The effectiveness of the treatment was both time and dose dependent. Humanized anti-MV-A iNOS rHJ mAb could rescue up to 80% of the challenged animal if administered early and at a high dose.
Conclusions Our conclusions are MV-A iNOS is a novel therapeutic target to treat sepsis; anti-MV-A iNOS mAbs can mitigate the harmful effects of MV-A iNOS; the neutralizing mAb’s efficacy is both time and dose dependent; and a specifically targeted immunotherapeutic for MV-A iNOS could potentially save tens-of-thousands of lives annually and could result in improved antibiotic stewardship.
Competing Interest Statement
Conflicts of Interest: RJ Webber and DS Webber are both paid executives and partial owners of Research & Diagnostic Antibodies the sponsor of the studies reported in this article. RM Sweet reports no conflict of interest. Sources of Funding: All studies reported in this article were funded exclusively by Research & Diagnostic Antibodies.
Footnotes
Conflicts of Interest: RJ Webber and DS Webber are both paid executives and partial owners of Research & Diagnostic Antibodies the sponsor of the studies reported in this article. RM Sweet reports no conflict of interest.
Sources of Funding: All studies reported in this article were funded exclusively by Research & Diagnostic Antibodies.