Purpose: An antibody-drug conjugate consisting of monomethyl auristatin E (MMAE) conjugated to the anti-CD30 monoclonal antibody (mAb) cAC10, with eight drug moieties per mAb, was previously shown to have potent cytotoxic activity against CD30 ؉ malignant cells. To determine the effect of drug loading on antibody-drug conjugate therapeutic potential, we assessed cAC10 antibody-drug conjugates containing different drug-mAb ratios in vitro and in vivo.Experimental Design: Coupling MMAE to the cysteines that comprise the interchain disulfides of cAC10 created an antibody-drug conjugate population, which was purified using hydrophobic interaction chromatography to yield antibody-drug conjugates with two, four, and eight drugs per antibody (E2, E4, and E8, respectively). Antibody-drug conjugate potency was tested in vitro against CD30؉ lines followed by in vivo xenograft models. The maximum-tolerated dose and pharmacokinetic profiles of the antibody-drug conjugates were investigated in mice.Results: Although antibody-drug conjugate potency in vitro was directly dependent on drug loading (IC 50 values E8

Site-specific conjugation of small molecules and enzymes to monoclonal antibodies has broad utility in the formation of conjugates for therapeutic, diagnostic, or structural applications. Precise control over the location of conjugation would yield highly homogenous materials that could have improved biological properties. We describe for the first time chemical reduction and oxidation methods that lead to preferential cleavage of particular monoclonal antibody interchain disulfides using the anti-CD30 IgG1 monoclonal antibody cAC10. Alkylation of the resulting cAC10 cysteine thiols with the potent antimitotic agent monomethyl auristatin E (MMAE) enabled the assignment of drug conjugation location by purification with hydrophobic interaction chromatography followed by analysis using reversed-phase HPLC and capillary electrophoresis. These analytical methods demonstrated that treating cAC10 with reducing agents such as DTT caused preferential reduction of heavy-light chain disulfides, while reoxidation of fully reduced cAC10 interchain disulfides caused preferential reformation of heavy-light chain disulfides. Following MMAE conjugation, the resulting conjugates had isomeric homogeneity as high as 60−90%, allowing for control of the distribution of molecular species. The resulting conjugates are highly active both in vitro and in vivo, and are well tolerated at efficacious doses.Monoclonal antibodies (mAbs) have been used extensively as carriers of fluorophores, radionuclides, cytotoxic agents, and enzymes, yielding conjugates that find utility in therapeutic (1-3) and imaging applications (4,5), ELISA-based assays (6), as well as for the investigation of protein structure and dynamics (7). The methods employed for making mAbbased conjugates can be classified in two general categories: those that involve the random modification of mAb amino acid residues, and those that are highly regioselective. Examples of random modification procedures include the acylation of lysine ε-amino groups (8), alkylation of tyrosines (9), and amidation of carboxylates (10). The biological and functional properties of these conjugates are often acceptable, however random modification of mAbs may impair antigen binding and leads to conjugate heterogeneity.In the past several years, a number of selective methods have been described to introduce molecules of interest onto mAbs. The ability to control the location and stoichiometry of conjugation can significantly improve the properties of mAb conjugates in some applications. The greatest selectivities are obtained using recombinant technologies for the production of fusion proteins (11)(12)(13)(14). Selective modification has also been reported for such chemically based methods as reductive amination of oxidized mAb carbohydrates (15), photoaffinity labeling of unconventional mAb binding sites (16), and reduction-alkylation of antibody interchain disulfides (17,18 We have previously described the preparation of mAb-drug conjugates for use as antitumor agents (17,19). The potent a...

Living organisms ubiquitously display colors that adapt to environmental changes, relying on the soft layer of cells or proteins. Adoption of soft materials into an artificial adaptive color system has promoted the development of material systems for environmental and health monitoring, anti-counterfeiting, and stealth technologies. Here, a hydrogel interferometer based on a single hydrogel thin film covalently bonded to a reflective substrate is reported as a simple and universal adaptive color platform. Similar to the cell or protein soft layer of color-changing animals, the soft hydrogel layer rapidly changes its thickness in response to external stimuli, resulting in instant color change. Such interference colors provide a visual and quantifiable means of revealing rich environmental metrics. Computational model is established and captures the key features of hydrogel stimuli-responsive swelling, which elucidates the mechanism and design principle for the broad-based platform. The single material-based platform has advantages of remarkable color uniformity, fast response, high robustness, and facile fabrication. Its versatility is demonstrated by diverse applications: a volatile-vapor sensor with highly accurate quantitative detection, a colorimetric sensor array for multianalyte recognition, breath-controlled information encryption, and a colorimetric humidity indicator. Portable and easy-to-use sensing systems are demonstrated with smartphone-based colorimetric analysis.

crown-6)] + (KC) cations are used for cocrystallization with manganese halides, producing isostructural single crystals of organic− inorganic hybrid complexes, [K(dibenzo-18-crown-6)] 2 MnX 4 (abbreviated (KC) 2 MnX 4 ) (X = Cl, Br), which feature one-dimensional morphology and green phosphorescence with considerable photoluminescence quantum yields accompanied by excellent optical waveguide behavior with a low loss coefficient. More interestingly, (KC) 2 MnX 4 crystallizes in the monoclinic space group Cc belonging to the achiral point group m (C s ), where the non-centrosymmetric arrangement of racemic units, with right-and left-handed rotating optical axes, endows these achiral single crystals with circularly polarized luminescence, observed for the first time.

Little is known about how racism and bias may be communicated in the medical record. This study used machine learning to analyze electronic health records (EHRs) from an urban academic medical center and to investigate whether providers' use of negative patient descriptors varied by patient race or ethnicity. We analyzed a sample of 40,113 history and physical notes (January 2019-October 2020) from 18,459 patients for sentences containing a negative descriptor (for example, resistant or noncompliant) of the patient or the patient's behavior. We used mixed effects logistic regression to determine the odds of finding at least one negative descriptor as a function of the patient's race or ethnicity, controlling for sociodemographic and health characteristics. Compared with White patients, Black patients had 2.54 times the odds of having at least one negative descriptor in the history and physical notes. Our findings raise concerns about stigmatizing language in the EHR and its potential to exacerbate racial and ethnic health care disparities.