scholarly journals Hexavalent Sperm-Binding IgG Antibody Released from Self-Dissolving Vaginal Film Enables Potent, On-Demand Non-Hormonal Female Contraception

2021 ◽  
Author(s):  
Bhawana Shrestha ◽  
Kathleen Vincent ◽  
Alison Schaefer ◽  
Yong Zhu ◽  
Gracie Vargas ◽  
...  
Keyword(s):  
Molecular Orientation ◽  
Expression System ◽  
Hormonal Contraception ◽  
Water Soluble ◽  
Motile Sperm ◽  
Igg Antibody ◽  
On Demand ◽  
Sperm Binding ◽  
Vaginal Film ◽  
Work Supports

Non-hormonal products for on-demand contraception are a global health technology gap, motivating us to pursue the use of sperm-binding monoclonal antibodies as a strategy to enable safe, effective, desirable, on-demand contraception. Here, using cGMP-compliant Nicotiana-expression system, we produce an ultra-potent sperm-binding IgG antibody possessing 6 Fab arms per molecule that bind a well-established contraceptive antigen target, CD52g. We term this hexavalent antibody Fab-IgG-Fab (FIF) to reflect its molecular orientation. The Nicotiana-produced FIF exhibits at least 10-fold greater sperm agglutination potency and kinetics than the parent IgG, while preserving Fc-mediated trapping of individual spermatozoa in mucus. We formulate the Nicotiana-produced FIF into a polyvinyl alcohol-based water-soluble contraceptive film, and evaluate its potency in reducing progressively motile sperm in the sheep vagina. Two minutes after vaginal instillation of human semen, no progressively motile sperm are recovered from the vaginas of sheep receiving FIF-Film. In contrast, high numbers of progressively motile sperm are recovered from sheep receiving a placebo film control. Our work supports the potential of highly multivalent contraceptive antibodies to provide safe, effective, on-demand non-hormonal contraception.

scholarly journals Hexavalent sperm-binding IgG antibody released from vaginal film for development of potent on-demand nonhormonal female contraception

2021 ◽  
Vol 118 (48) ◽  
pp. e2107832118
Author(s):  
Bhawana Shrestha ◽  
Kathleen Vincent ◽  
Alison Schaefer ◽  
Yong Zhu ◽  
Gracie Vargas ◽  
...  
Keyword(s):  
Expression System ◽  
Unmet Need ◽  
Water Soluble ◽  
Motile Sperm ◽  
Human Semen ◽  
Igg Antibody ◽  
On Demand ◽  
Sperm Binding ◽  
Vaginal Film ◽  
Work Supports

Nonhormonal products for on-demand contraception are a global health technology gap; this unmet need motivated us to pursue the use of sperm-binding monoclonal antibodies to enable effective on-demand contraception. Here, using the cGMP-compliant Nicotiana-expression system, we produced an ultrapotent sperm-binding IgG antibody possessing 6 Fab arms per molecule that bind a well-established contraceptive antigen target, CD52g. We term this hexavalent antibody “Fab-IgG-Fab” (FIF). The Nicotiana-produced FIF had at least 10-fold greater sperm-agglutination potency and kinetics than the parent IgG, while preserving Fc-mediated trapping of individual spermatozoa in mucus. We formulated the Nicotiana-produced FIF into a polyvinyl alcohol–based water-soluble contraceptive film and evaluated its potency in reducing progressively motile sperm in the sheep vagina. Two minutes after vaginal instillation of human semen, no progressively motile sperm were recovered from the vaginas of sheep receiving FIF Film. Our work supports the potential of multivalent contraceptive antibodies to provide safe, effective, on-demand nonhormonal contraception.

scholarly journals Engineering highly multivalent sperm-binding IgG antibodies for potent non-hormonal female contraception

2020 ◽  
Author(s):  
Bhawana Shrestha ◽  
Alison Schaefer ◽  
Jamal Saada ◽  
Zhu Yong ◽  
Timothy M. Jacobs ◽  
...  
Keyword(s):  
Hormonal Contraception ◽  
Human Sperm ◽  
Hormonal Contraceptive ◽  
Medical Applications ◽  
Motile Sperm ◽  
Igg Antibodies ◽  
Contraceptive Methods ◽  
Sperm Binding ◽  
Polymeric Immunoglobulins ◽  
Unique Surface

AbstractMany women risk unintended pregnancy due to dissatisfaction with available hormonal contraceptive methods. This led us to pursue topical sperm-binding monoclonal antibodies as a strategy for safe, non-hormonal contraception. Motivated by the greater agglutination potencies of polymeric immunoglobulins such as IgM and the exceptional bioprocessing ease in manufacturing IgG, we engineered IgGs possessing 6-10 Fabs against a unique surface antigen universally present on human sperm. These highly multivalent IgGs (HM-IgGs) are at least 10- to 16-fold more potent and faster than the parent IgG at agglutinating sperm, while preserving Fc-mediated trapping of individual spermatozoa in mucus. The increased potencies translate to effective (>99.9%) reduction of progressively motile sperm in the sheep vagina using 33 micrograms of the 10 Fab HM-IgG. HM-IgGs produce at comparable yields and possess identical thermal stability to the parent IgG, with greater homogeneity. HM-IgGs represent not only promising biologics for non-hormonal contraception but also a promising platform for generating potent agglutinating mAb for diverse medical applications.

scholarly journals Development, Characterization and In Vivo Pharmacokinetic Assessment of Rectal Suppositories Containing Combination Antiretroviral Drugs for HIV Prevention

Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1110
Author(s):  
Kunal Jhunjhunwala ◽  
Charles W. Dobard ◽  
Sunita Sharma ◽  
Natalia Makarova ◽  
Angela Holder ◽  
...  
Keyword(s):  
Hiv Prevention ◽  
Antiretroviral Drugs ◽  
Water Soluble ◽  
Fixed Dose ◽  
Receptive Anal Intercourse ◽  
On Demand ◽  
Dose Combination ◽  
Rectal Suppositories

Receptive anal intercourse (RAI) contributes significantly to HIV acquisition underscoring the need to develop HIV prevention options for populations engaging in RAI practices. We explored the feasibility of formulating rectal suppositories with potent antiviral drugs for on-demand use. A fixed-dose combination of tenofovir (TFV) and elvitegravir (EVG) (40 mg each) was co-formulated in six different suppository bases (three fat- and three water-soluble). Fat-soluble witepsol H15 and water-soluble polyethylene glycol (PEG) based suppositories demonstrated favorable in vitro release and were advanced to assess in vivo pharmacokinetics following rectal administration in macaques. In vivo drug release profiles were similar for both suppository bases. Median concentrations of TFV and EVG detected in rectal fluids at 2 h were 1- and 2-logs higher than the in vitro IC50, respectively; TFV-diphosphate levels in rectal tissues met or exceeded those associated with high efficacy against rectal simian HIV (SHIV) exposure in macaques. Leveraging on these findings, a PEG-based suppository with a lower dose combination of tenofovir alafenamide (TAF) and EVG (8 mg each) was developed and found to achieve similar rectal drug exposures in macaques. This study establishes the utility of rectal suppositories as a promising on-demand strategy for HIV PrEP and supports their clinical development.

scholarly journals Domain-structure analysis of recombinant rat hormone-sensitive lipase

1996 ◽  
Vol 319 (2) ◽  
pp. 411-420 ◽  
Author(s):  
Torben ØSTERLUND ◽  
Birgitta DANIELSSON ◽  
Eva DEGERMAN ◽  
Juan Antonio CONTRERAS ◽  
Gudrun EDGREN ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Domain Structure ◽  
Expression System ◽  
Guanidine Hydrochloride ◽  
Catalytic Triad ◽  
Water Soluble ◽  
Hormone Sensitive Lipase ◽  
Structural Domain ◽  
Hydrolase Fold ◽  
Hormone Sensitive

Hormone-sensitive lipase (HSL) plays a key role in lipid metabolism and overall energy homoeostasis, by controlling the release of fatty acids from stored triglycerides in adipose tissue. Lipases and esterases form a protein superfamily with a common structural fold, called the α/β-hydrolase fold, and a catalytic triad of serine, aspartic or glutamic acid and histidine. Previous alignments between HSL and lipase 2 of Moraxella TA144 have been extended to cover a much larger part of the HSL sequence. From these extended alignments, possible sites for the catalytic triad and α/β-hydrolase fold are suggested. Furthermore, it is proposed that HSL contains a structural domain with catalytic capacity and a regulatory module attached, as well as a structural N-terminal domain unique to this enzyme. In order to test the proposed domain structure, rat HSL was overexpressed and purified to homogeneity using a baculovirus/insect-cell expression system. The purification, resulting in > 99% purity, involved detergent solubilization followed by anion-exchange chromatography and hydrophobic-interaction chromatography. The purified recombinant enzyme was identical to rat adipose-tissue HSL with regard to specific activity, substrate specificity and ability to serve as a substrate for cAMP-dependent protein kinase. The recombinant HSL was subjected to denaturation by guanidine hydrochloride and limited proteolysis. These treatments resulted in more extensive loss of activity against phospholipid-stabilized lipid substrates than against water-soluble substrates, suggesting that the hydrolytic activity can be separated from recognition of lipid substrates. These data support the concept that HSL has at least two major domains.

A flexible yet wear-resistant co-citrate elastomer for on-demand disposable patch sensors

2020 ◽  
Vol 8 (29) ◽  
pp. 10047-10059 ◽  
Author(s):  
Do-Gwan Kim ◽  
Dowon Ahn ◽  
Kang-Han Kim ◽  
Yong-Cheol Jeong
Keyword(s):  
Wear Resistance ◽  
Strain Sensor ◽  
Metal Electrode ◽  
Ph Sensitive ◽  
Water Soluble ◽  
Wear Resistant ◽  
On Demand

Herein, we report a wearable strain sensor, composed of a water-soluble metal electrode and a pH-sensitive encapsulation layer, with conforming flexibility and super wear-resistance.

Mechanistic study of a manganese porphyrin catalyst for on-demand production of chlorine dioxide in water

2015 ◽  
Vol 19 (01-03) ◽  
pp. 492-499 ◽  
Author(s):  
Scott D. Hicks ◽  
Silei Xiong ◽  
Curt J. Bougher ◽  
Grigori A. Medvedev ◽  
James Caruthers ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Chlorine Dioxide ◽  
Transfer Reaction ◽  
Water Soluble ◽  
Reaction Pathways ◽  
Mechanistic Study ◽  
Manganese Porphyrin ◽  
Oxygen Atom Transfer ◽  
On Demand ◽  
Proton Coupled Electron Transfer

A water-soluble manganese porphyrin complex was examined for the catalytic formation of chlorine dioxide from chlorite under ambient temperature at pH 5.00 and 6.90. Quantitative kinetic modeling allowed for the deduction of a mechanism that accounts for all experimental observations. Catalysis is initiated via an OAT (Oxygen Atom Transfer) reaction resulting in formation of a putative manganese(V) oxo species, which undergoes ET (Electron Transfer) with chlorite to form chlorine dioxide. As chlorine dioxide accumulates in solution, chlorite consumption slows down and ClO 2 reaches a maximum as the system reaches equilibrium. In phosphate buffer at pH 6.90, manganese(IV) oxo accumulates and its reaction with ClO 2 gives ClO 3-. However, at pH 5.00 acetate buffer proton coupled electron transfer (PCET) from chlorite to manganese(IV) oxo is fast and irreversible leading to chlorate formation only via the putative manganese(V) oxo species. These differences underscore how PCET rates affect reaction pathways and mechanism. The ClO 2 product can be collected from the aqueous reaction mixture via purging with an inert gas, allowing for the preparation of chlorine dioxide on-demand.

scholarly journals A SPION-eicosane protective coating for water soluble capsules: Evidence for on-demand drug release triggered by magnetic hyperthermia

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Laili Che Rose ◽  
Joseph C. Bear ◽  
Paul D. McNaughter ◽  
Paul Southern ◽  
R. Ben Piggott ◽  
...  
Keyword(s):  
Drug Release ◽  
Protective Coating ◽  
Magnetic Hyperthermia ◽  
Water Soluble ◽  
On Demand

scholarly journals Programming function into mechanical forms by directed assembly of silk bulk materials

2016 ◽  
Vol 114 (3) ◽  
pp. 451-456 ◽  
Author(s):  
Benedetto Marelli ◽  
Nereus Patel ◽  
Thomas Duggan ◽  
Giovanni Perotto ◽  
Elijah Shirman ◽  
...  
Keyword(s):  
Self Assembly ◽  
Biological Function ◽  
Bulk Material ◽  
Directed Assembly ◽  
Water Soluble ◽  
Infrared Light ◽  
Bulk Materials ◽  
Protein Matrix ◽  
On Demand ◽  
Water Based

We report simple, water-based fabrication methods based on protein self-assembly to generate 3D silk fibroin bulk materials that can be easily hybridized with water-soluble molecules to obtain multiple solid formats with predesigned functions. Controlling self-assembly leads to robust, machinable formats that exhibit thermoplastic behavior consenting material reshaping at the nanoscale, microscale, and macroscale. We illustrate the versatility of the approach by realizing demonstrator devices where large silk monoliths can be generated, polished, and reshaped into functional mechanical components that can be nanopatterned, embed optical function, heated on demand in response to infrared light, or can visualize mechanical failure through colorimetric chemistries embedded in the assembled (bulk) protein matrix. Finally, we show an enzyme-loaded solid mechanical part, illustrating the ability to incorporate biological function within the bulk material with possible utility for sustained release in robust, programmably shapeable mechanical formats.

Ionotropically Gelled Bicontinuous Cubic Phase as a Matrix for Controlled Release

1993 ◽  
Vol 331 ◽  
Author(s):  
S. Puvvada ◽  
J. Naciri ◽  
B. R. Ratna
Keyword(s):  
Release Rate ◽  
Release Profile ◽  
Water Soluble ◽  
Cubic Phase ◽  
First Order ◽  
On Demand ◽  
Release Studies ◽  
Order Release ◽  
Bicontinuous Cubic ◽  
Soluble Polysaccharide

AbstractRelease studies from a lipid-based matrix, known as the bicontinuous cubic phase, are presented. This matrix consists of nano-sized pores within which various proteins and drugs can be dispersed and subsequently released to the exterior. To control the release rate, the aqueous pores of the cubic phase were gelled using sodium alginate, a water soluble polysaccharide. Studies show that the release rate is significantly lowered upon gelation and the first order release profile exhibited by the ungelled cubic phase is converted to a zeroorder linear profile. Further, it has been shown that the release trends can be reversed by degelation. This opens up the possibility of releasing large quantities of the protein when required (drugs on demand concept) by degelling the gelled samples.

scholarly journals Functional Expression of a DNA-Topoisomerase IB fromCryptosporidium parvum

2009 ◽  
Vol 2009 ◽  
pp. 1-9 ◽  
Author(s):  
César Ordóñez ◽  
Javier Alfonso ◽  
Rafael Balaña-Fouce ◽  
David Ordóñez
Keyword(s):  
Expression System ◽  
Functional Expression ◽  
Structural Features ◽  
Water Soluble ◽  
Irreversible Inhibitor ◽  
Dna Topoisomerase ◽  
Yeast Expression System ◽  
Topoisomerase Ib ◽  
Single Polypeptide

Cryptosporidium parvum, one of the most important causative organisms of human diarrheas during childhood, contains a monomeric DNA-topoisomerase IB (CpTopIB) in chromosome 7. Heterologous expression ofCpTopIBgene in a budding yeast strain lacking this activity proves that the cryptosporidial enzyme is functional in vivo. The enzymatic activity is comprised in a single polypeptide, which contains all the structural features defining a fully active TopIB. Relaxation activity of the yeast extracts was detected only whenCpTopIBORF was expressed in a yeast expression system showing time and protein dependence under steady state kinetic conditions. The susceptibility of CpTopIB-transformed yeast to the irreversible inhibitor camptothecin and its water-soluble derivatives (topotecan and SN-38) was assessed.

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