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Whaley, K.

Publications and source records attributed to Whaley, K..

4 recordsLinked to original sources

Revolutionizing male contraception: Personal lubricants as a novel way to deliver the Human Contraception Antibody

Study QuestionCan personal lubricants effectively deliver the sperm-agglutinating Human Contraception Antibody (HCA) to achieve on-demand male contraception? Summary AnswerThis study demonstrates that several water-based lubricants can effectively deliver bioactive HCA, and that a dimethicone-containing silicone lubricant can be modified into a stable emulsion suitable for antibody delivery. What Is Known AlreadyThe HCA-based vaginal film ZB-06 was shown to be safe and effective in a Phase I clinical trial for female contraception. Male contraceptive options remain limited. Using sexual lubricants as a delivery platform for HCA represents a novel and practical approach to male contraception. Study Design, Size, DurationWe tested the stability of HCA for up to two years in a variety of commercially available sexual lubricants, and its delivery from a penile device using a simulated intercourse model. Participants/Materials, Setting, MethodsFourteen commercial lubricants were initially screened for impact on sperm motility and viability, miscibility with HCA solution, and preservation of HCA activity (sperm agglutination test). From these, three water-based and one silicone-based lubricant were selected for further study. The silicone-based product was engineered into a novel emulsion (KY-DE) by incorporating 6% w/w PEG-10 dimethicone and 0.005% v/v TWEEN-20 for HCA integration. Formulations were tested for HCA functional stability and contraceptive efficacy over time using kinetic sperm agglutination assays and a capillary tube sperm penetration test. A novel simulated intercourse model was developed using a 3D-printed penile device and a vaginal analog (Fleshlight(R)). HCA-lube was applied to the "penis", and concentrations of HCA delivered to the "vagina" during intercourse were measured by ELISA and sperm agglutination assay. Safety evaluations were conducted using a vaginal tissue model (EpiVaginal, VEC-100-FT). Viability (MTT assay), tight junction integrity (TEER), and cytokine release were assessed after application of HCA-lube. Main Results and the Role of ChanceAll selected lubricants were nontoxic and did not affect HCAs ability to agglutinate sperm. In the capillary tube sperm penetration assay, HCA-formulated lubricants significantly impaired sperm penetration; few motile sperm penetrated past a depth of 1 cm after 90 minutes in the HCA-lubricants vs >80_in most of the untreated lubricants. Importantly, the simulated intercourse assay confirmed successful delivery of HCA to the vagina. Water-based lubricants delivered an average of 24 {+/-} 8.4 {micro}g/mL of HCA, the commercial silicone lubricant 11 {+/-} 5.2 {micro}g/mL, and the KY-DE emulsion 27.4 {+/-} 22.4 {micro}g/mL. Futhermore, the formulations did not compromise tissue integrity or viability, or induce significant inflammatory responses. Large Scale DataNot applicable. Limitations, Reasons for CautionWhile these in vitro results support the feasibility of using lubricants as HCA delivery vehicles, translation into clinical application requires further validation and clinical trials. Wider Implications of the FindingsThis work presents a new direction in male contraceptive development, leveraging the widespread use of personal lubricants to introduce antibody-based, reversible, on-demand contraception. Engineering a silicone-based lubricant that retains HCA activity under varied conditions and ensures higher mucosal delivery could further advance this approach. Study Funding/Competing Interest(s)This work was supported by a Sokol Grant from the Male Contraceptive Initiative, a Sexual Medicine Grant from Boston University Chobanian & Avedisian School of Medicine, and grant P50HD096957 from the National Institutes of Health. Kevin Whaley (ZabBio) intends to commercialize HCA for contraception. None of the other authors have competing interests.

bioengineering↗

Inhibition of Invasive Salmonella by Orally Administered IgA and IgG Monoclonal Antibodies

BackgroundNon-typhoidal Salmonella enterica strains, including serovar Typhimurium (STm), are an emerging cause of invasive disease among children and the immunocompromised, especially in regions of sub-Saharan Africa. STm invades the intestinal mucosa through Peyers patch tissues before disseminating systemically. While vaccine development efforts are ongoing, the emergence of multidrug resistant strains of STm affirms the need to seek alternative strategies to protect high-risk individuals from infection.\n\nMethodology/Principal FindingsIn this report we investigated the potential of an orally administered O5 serotype-specific IgA monoclonal antibody (mAb), called Sal4, to protect mice against invasive Salmonella enterica serovar Typhimurium (STm) infection. Sal4 IgA was delivered to mice prior to or concurrently with STm challenge. Infectivity was measured as bacterial burden in Peyers patch tissues one day after challenge. Using this model, we defined the minimal amount of Sal4 IgA required to significantly reduce STm uptake into Peyers patches. The relative efficacy of Sal4 in dimeric and secretory IgA (SIgA) forms was compared, as was a second lower avidity O5-specific IgA mAb that we produced from STm immunized mice. To assess the role of isotype in oral passive immunization, we engineered a recombinant IgG1 mAb carrying the Sal4 variable regions and evaluated its ability to block invasion of STm into epithelial cells in vitro and Peyers patch tissues.\n\nConclusions/SignificanceOur results demonstrate the potential of orally administered monoclonal IgA and SIgA, but not IgG, to passively immunize against invasive Salmonella. Nonethless, the prophylactic window of IgA/SIgA in the mouse was on the order of minutes, underscoring the need to develop formulations to protect mAbs in the gastric environment and to permit sustained release in the small intestine.\n\nAuthor SummaryThe bacterium Salmonella enterica is responsible for significant morbidity and mortality in the developed and developing worlds. While the pathogen is most renowed as the causative agent of typhoid fever, the emergence of invasive non-typhoid strains like S. enterica serovar Typhimurium (STm) are of great concern because of their propensity to cause severe disease in children under the age of five. In this report, we demonstrate in a mouse model that oral administration of a monoclonal antibody targeting the surface of STm is able to prevent the bacterium from infecting gastrointestinal tissues, the first step in the dissemination process. We show that IgA antibodies (which are normally found in the gut) were far superior than an equivalent IgG antibody (normally found in blood) at protecting the intestine from STm infection. These results lay the foundation for future studies aimed at the development of an orally administered antibody cocktail capable of providing temporary immunity to pathogens like S. enterica.

immunology↗

Therapeutic Treatment of Aerosolized Staphylococcal Enterotoxin B in Nonhuman Primates with two Monoclonal Antibodies

Staphylococcal enterotoxin B (SEB) is a protein exotoxin found on the cell surface of Staphylococcus aureus that is the source for multiple pathologies in man. When purified and concentrated in aerosol form, SEB can cause an acute and often fatal intoxication, and thus is considered a biological threat agent. There are currently no vaccines or treatments approved for human use. Studies in rodent models of SEB intoxication show that antibody therapy may be a promising treatment strategy, however many have used antibodies only prophylactically or well before any clinical signs of intoxication are apparent. We assessed and compared the protective efficacy of two monoclonal antibodies, Ig121 and c19F1, when administered after aerosol exposure in a uniformly lethal nonhuman primate model of SEB intoxication. Rhesus macaques were challenged using small particle aerosols of SEB, and then were infused intravenously with a single dose of either Ig121 or c19F1 (10 mg/kg) at either 0.5, 2 or 4 hours postexposure. Onset of clinical signs, hematological, and cytokine response in untreated controls confirmed the acute onset and potency of the toxin used in the challenge. All animals administered either Ig121 or c19F1 survived SEB challenge, whereas the untreated controls succumbed to SEB intoxication 30-48 hours postexposure. These results represent the successful therapeutic in vivo protection by two investigational drugs against SEB in a severe nonhuman primate disease model and punctuate the therapeutic value of monoclonal antibodies hold when faced with treatment options for SEB-induced toxicity in a postexposure setting.\n\nOne Sentence Summary: Two high-affinity monoclonal antibodies were tested for therapeutic efficacy using a rhesus macaque challenge model of aerosolized SEB

immunology↗

Humanized Monoclonal Antibody Rescues Rhesus macaques from Aerosolized Ricin Toxin Exposure

Ricin toxin (RT) ranks at the top of the list of potential bioweapons of concern to civilian and military personnel alike due to its high potential for morbidity and mortality after inhalation. In non-human primates, aerosolized ricin triggers a severe acute respiratory distress characterized by perivascular and alveolar edema, neutrophilic infiltration, and severe necrotizing bronchiolitis and alveolitis. There are currently no approved countermeasures for ricin intoxication. In this report, we demonstrate the therapeutic potential of huPB10, a toxin-neutralizing humanized monoclonal antibody (MAb) against an immunodominant epitope on ricins enzymatic A chain (RTA). Five rhesus macaques that received intravenous huPB10 (10 mg/kg) four hours after lethal dose ricin aerosol exposure all survived the toxin challenge, as compared to control animals, which succumbed to ricin intoxication within 30 h. Antibody treatment at 12 h after ricin exposure resulted in the survival of only one of five monkeys, indicating that, in the majority of animals, ricin intoxication and local tissue damage had progressed beyond the point where huPB10 intervention was beneficial. Change in pro-inflammatory cytokine/chemokines levels in bronchial alveolar lavage fluids before and after toxin challenge successfully clustered monkeys based on survival, as well as treatment group. IL-6 was the most apparent marker of ricin intoxication. This study represents the first demonstration in nonhuman primates that the lethal effects of inhalational ricin exposure can be negated by a drug candidate and opens up a path forward for product development.

immunology↗