298 research outputs found
Engineering next generation therapeutics to combat infectious diseases
Of the 56 therapeutic monoclonal antibody products currently marketed in the US, four now target infectious disease indications. An additional 40 recombinant antibodies are in clinical trials for infectious indications, with 29 in phase II or III trials. The evolution of antibiotic-resistant bacteria, the emergence of new pathogens, and a growing population of immunocompromised individuals means that in many cases antibodies are an increasingly attractive therapeutic option. Next-generation antibody formats, including antibody-drug conjugates and single-domain antibodies as well as antibody mixtures and bispecific antibodies provide access to novel therapeutic mechanisms and allow for targeting a wider range of epitopes. This talk will provide an overview of recent advances in the field and highlight two on-going projects in my lab. First, to address a resurgence in pertussis in high resource countries and continued high rates of morbidity and mortality in low resource countries, we have developed and antibody therapeutic neutralizing the toxin primarily responsible for symptoms. This antibody has been engineered for high affinity binding, reduced immunogenicity and extended serum half-life. We have also characterized its mechanism of action, using biochemical, structural and cellular assays. We have shown hu1B7 is protective against disease in mouse and adolescent baboon models of disease. Moreover, a single dose can prevent disease symptoms in a neonatal baboon model when administered five weeks before experimental challenge. Second, to address issues with recurrent cytomegalovirus infection in immuno-suppressed individuals, we envision a bispecific antibody able to redirect any passing T cells toward CMV suppression. In our first iteration of this therapeutic, we aim to target infected cells via a T cell receptor (TCR) binding the immuno-dominant peptide-HLA complex. Since TCRs are typically low affinity and express poorly as soluble molecules, we have used a novel eukaryotic-based cell display system that allowed us to rapidly identify variants with higher affinity and enhanced stability. We have generated TCR variants with up to 100-fold improved affinity that retain exquisite peptide selectivity. We will report our initial efforts to use this modified TCR to target CMV-infected cells
Relations Among Brief Measures of Mathematics, Reading, and Processing Speed: A Construct Validity Study
Emphasis on regular mathematics skill assessment, intervention, and progress monitoring under the RTImodel has created a need for the development of assessment instruments that are psychometrically sound, reliable, universal, and brief. Important factors to consider when developing or selecting assessments for the school environment include what skills are assessed; mathematics curriculums typically include computation and applications as separate skills taught in sequence. It is also important to consider what additional factors may potentially influence performance on such tests due to the nature of test administration and characteristics of the test items. The current study investigated the construct validity of established, widely-used curriculum-based measurement (CBM)tests and standardized, norm-referenced tests of mathematics as well as the potential confounding influence of processing speed and reading abilities. Construct validity of the tests was assessed through an investigation of convergent and discriminant validity, using confirmatory factor analysis (CFA). Numerous prespecified, theoretical models were tested to replicate previous studies suggesting specific models of mathematics ability (convergent validity) and to identify construct-irrelevant variance (discriminant validity) imposed on tests of computation and applications by processing speed and reading. The current study extended previous work in the area of mathematics providing additional evidence for a two-factor structure of mathematics with Computation and Applications as distinct, yet related constructs and investigated the relations between mathematics constructs and processing speed and reading. Results of the current study indicated all constructs were significantly correlated with each other while mathematics constructs were more highly correlated with each other than with unrelated constructs, with the exception of Applications and Reading. Four a priori models of mathematics ranging from including a single factor to including four factors were tested using CFA. Results indicated that a four-factor model of mathematics including Computation, Applications, Processing Speed, and Readingas factors was the best-fitting model. The four-factor model was extended to test the construct-irrelevant variance imposed by Processing Speed on fluency-based tests as well as variance imposed by Reading on applications tests. Results indicated that in all but one case, no significant influence was contributed to fluency-based tests by Processing Speed or applications tests by Reading
Class Lives: Stories From Across our Economic Divide
[Excerpt] Class is the last great taboo in the United States. It is, according to Noam Chomsky, “the unmentionable five-letter word.” Even in this period of growing economic inequality, we hardly ever talk about class. We hear daily, in the mainstream media, about unemployment, bailouts, proposed tax cuts or tax hikes, Congress regulating one industry and deregulating another, budget cuts, recession, recovery, roller-coaster markets, CEO bonuses, and more. Given all the attention to economics, it is interesting that talk about social class has been so skimpy.
Sometimes I think of class as our collective, national family secret. And, as any therapist will tell you, family secrets are problematic. With rare exceptions, we just don’t talk about class in the United States. Most of us believe that the United States is a classless society, one that is basically middle class (except for a few unfortuÂnate poor people and some lucky rich ones). Sometimes talk about class is really about race. We have no shared language about class. We have been taught from childhood myths and misconceptions around class mobility and the American dream.
Many of us are confused about class and don’t tend to think about it as consciously as we might our race, ethnicity, gender, religion, age, or sexual orientation. Nonetheless, our class identity has a huge impact on every aspect of our lives: from parenting style to how we speak, from what we dare to dream to the likelihood we will spend time in prison, from how we spend our days to how many days we have.
We are living in a period of extraordinary economic insecurity and inequality. It is an inequality that crushes the poor, drains the working class, eliminates the middle class, simultaneously aggrandizes and dehumanizes the rich, and disembowels democracy
Antibody engineering on the surface of CHO cells
From discovery to market, antibody therapeutics are developed using several expression platforms. Antibodies are often discovered from isolated mouse or human B-cells, engineered for affinity and specificity on the surface of phage, bacteria, or yeast, and manufactured in FDA-approved mammalian cell lines. This functional engineering detour in non-mammalian platforms introduces the opportunity to adversely impact expression and stability of the final product in the mammalian production cell line. To address this shortcoming, a CHO cell display platform was developed in which the antibody therapeutic can be engineered in the CHO manufacturing cell line, streamlining the process (Fig.1). CHO cell display of an antibody Fab fragment was developed and optimized using a semi-stable episomal system capable of maintenance of a transfected plasmid for several weeks, which allows multiple rounds of flow cytometric sorting and regrowth of promising clones.
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Next generation antibody and TCR therapeutics for infectious disease
Parasitic and infectious diseases cause over 9.5 million deaths worldwide annually, yet only 3 of the over 50 approved antibodies are for infectious conditions. This disparity can be attributed to the high costs of antibody development in the face of small molecule alternatives and effective vaccines; however, a growing niche of specialty applications and the emergence of antibioticresistant strains make antibody therapeutics a likely eventuality. Particular challenges for developing therapeutic proteins for pathogenic diseases are that high variability in circulating strains, mutability within the host, and immune escape mechanisms limits the efficacy of monoclonal antibody formats. Instead, next generation formats that can exhibit broader activity or induce novel immune mechanisms may be a viable approach. T-cell receptors (TCRs) are membrane-bound molecules that bind peptide-MHC (pMHC) molecules displayed by host cells, and are experts at recognizing infected cells. We have replaced one arm of a bispecific antibody with a soluble TCR to make a novel TCR/Ig hybrid. To do this, we first developed a system which can display TCRs on the surface of CHO cells. After optimization of the TCR format, in particular constant region modifications, we replaced the transmembrane region of the construct with an IgG1 hinge and Fc to express and purify soluble fusions. By including a knob or hole mutation in the Fc region, we were able to make bispecific molecules. Our current format couples an anti-CD3 antibody specificity to a human TCR that is associated with cytomegalovirus (CMV). We hypothesize that this format may have unique ability to suppress CMV reactivation or infection in transplant recipients or pregnant women. Ongoing work includes affinity maturation of the TCR, as well as testing the bispecific in a cellular model of CMV
Angiogenic Biomarkers for Risk Stratification in Women with Suspected Preeclampsia
This poster presents the results of a single-center prospective cohort study of 315 pregnant women who presented to George Washington University Hospital Labor and Delivery service with a clinical suspicion of preeclampsia between February 2007 and November 2011. Informed consent was obtained. Baseline demographic information and medical history was collected on each patient including maternal age, ethnicity, body mass index, tobacco and other substance use, gestational age, medical problems and obstetric history. Serum samples were obtained from each enrolled subject within 24 hours of admission, and sFlt1, PlGF and sEng ELISA assays were performed in duplicate by a blinded laboratory technician at the University of Massachusetts
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Humanized pertussis antibodies and uses thereof
The present invention relates to humanized antibodies which bind the pertussis toxin protein and their use as therapeutic agents. In particular, the present invention is directed to improved humanized 1B7 and 11E6 antibodies which bind the pertussis toxin protein.Board of Regents, University of Texas Syste
Latino Business Owners In East Boston
The main objective of this research was to investigative the contribution of Latino immigrant business owners (or entrepreneurs) in East Boston. Twelve Latino business owners in East Boston were interviewed and supplementary interviews with public officials and other key informants served to further document the contribution of Latino entrepreneurs. The main finding of the report is that Latino business owners have made, and continue, to make extremely important contributions to East Boston’s economy and neighborhoods
Forearm EMG During Rock Climbing Differs from EMG During Handgrip Dynamometry
Grip force, as measured via handgrip dynamometry, is often given importance in the study of rock climbing performance. Whether handgrip dynamometry produces a degree of muscle activation comparable to actual climbing has not been reported. Furthermore, the degree and variability of muscle activation for various configurations during climbing are unknown. The purpose of this study was to record forearm EMG responses for six hand configurations during climbing and to compare these responses to a maximum handgrip test. Five experienced climbers signed informed consent to participate in the study. Subjects performed four moves up (UP) and down (DN) on an overhanging 45-deg. climbing wall with each of six hand configurations: crimp (C), pinch (P), three 2-finger combinations (2F1, 2F2, 2F3) and an open-hand grip (O). Forearm EMG was recorded via surface electrodes. Data were recorded for the second UP and second DN moves. Prior to climbing, maximum handgrip force (HG) and simultaneous EMG were obtained. Mean HG force was 526.6±33.3 N. Times to complete the climbing movements with each hand configuration varied between 3.1±0.5 and 4.8±0.9 sec, however no significant differences were found. All peak EMG’s during climbing were higher than HG EMG (p\u3c.05). Mean EMG amplitudes for UP, expressed as percentages of HG EMG, were 198±55, 169±22, 222±72, 181±39, 126±32, and 143±47% for C, P, 2F1, 2F2, 2F3, and O respectively. Significant differences were found for O versus 2F1 and for 2F3 versus 2F1 and C (p\u3c.05). All EMG amplitudes were lower for DN than UP (p\u3c.05). Since all climbing EMGs exceeded HG EMG, it was concluded that handgrip dynamometry lacks specificity to actual rock climbing
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