Publications

We used high throughput sequencing to examine the structure and composition of the T cell receptor β chain in Common Variable Immune Deficiency (CVID). TCRβ CDR3 regions were amplified and sequenced from genomic DNA of 44 adult CVID subjects and 22 healthy adults, using a high-throughput multiplex PCR. CVID TCRs had significantly less junctional diversity, fewer n-nucleotide insertions and deletions, and completely lacked a population of highly modified TCRs, with 13 or more V-gene nucleotide deletions, seen in healthy controls. The CVID CDR3 sequences were significantly more clonal than control DNA, and displayed unique V gene usage. Despite reduced junctional diversity, increased clonality and similar infectious exposures, DNA of CVID subjects shared fewer TCR sequences as compared to controls. These abnormalities are pervasive, found in out-of-frame sequences and thus independent of selection and were not associated with specific clinical complications. These data support an inherent T cell defect in CVID.

Contractile motion is the simplest metric of cardiomyocyte health in vitro, but unbiased quantification is challenging. We describe a rapid automated method, requiring only standard video microscopy, to analyze the contractility of human-induced pluripotent stem cell-derived cardiomyocytes (iPS-CM). New algorithms for generating and filtering motion vectors combined with a newly developed isogenic iPSC line harboring genetically encoded calcium indicator, GCaMP6f, allow simultaneous user-independent measurement and analysis of the coupling between calcium flux and contractility. The relative performance of these algorithms, in terms of improving signal to noise, was tested. Applying these algorithms allowed analysis of contractility in iPS-CM cultured over multiple spatial scales from single cells to three-dimensional constructs. This open source software was validated with analysis of isoproterenol response in these cells, and can be applied in future studies comparing the drug responsiveness of iPS-CM cultured in different microenvironments in the context of tissue engineering.

Acute insults produce hyperalgesic priming, a neuroplastic change in nociceptors that markedly prolongs inflammatory mediator-induced hyperalgesia. After an acute initiating insult, there is a 72 h delay to the onset of priming, for which the underlying mechanism is unknown. We hypothesized that the delay is due to the time required for a signal to travel from the peripheral terminal to the cell body followed by a return signal to the peripheral terminal. We report that when an inducer of hyperalgesic priming (monocyte chemotactic protein 1) is administered at the spinal cord of Sprague Dawley rats, priming is detected at the peripheral terminal with a delay significantly shorter than when applied peripherally. Spinally induced priming is detected not only when prostaglandin E2 (PGE2) is presented to the peripheral nociceptor terminals, but also when it is presented intrathecally to the central terminals in the spinal cord. Furthermore, when an inducer of priming is administered in the paw, priming can be detected in spinal cord (as prolonged hyperalgesia induced by intrathecal PGE2), but only when the mechanical stimulus is presented to the paw on the side where the priming inducer was administered. Both spinally and peripherally induced priming is prevented by intrathecal oligodeoxynucleotide antisense to the nuclear transcription factor CREB mRNA. Finally, the inhibitor of protein translation reversed hyperalgesic priming only when injected at the site where PGE2 was administered, suggesting that the signal transmitted from the cell body to the peripheral terminal is not a newly translated protein, but possibly a newly expressed mRNA.

BACKGROUND

. While choices about genetic testing are increasingly common for patients and families, and public opinion surveys suggest public interest in genomics, it is not known how adults from the general population value genetic testing for heritable conditions. We sought to understand in a US sample the relative value of the characteristics of genetic tests to identify risk of hereditary colorectal cancer, among the first genomic applications with evidence to support its translation to clinical settings.

METHODS

. A Web-enabled choice-format conjoint survey was conducted with adults age 50 years and older from a probability-based US panel. Participants were asked to make a series of choices between 2 hypothetical blood tests that differed in risk of false-negative test, privacy, and cost. Random parameters logit models were used to estimate preferences, the dollar value of genetic information, and intent to have genetic testing.

RESULTS

. A total of 355 individuals completed choice-format questions. Cost and privacy were more highly valued than reducing the chance of a false-negative result. Most (97% [95% confidence interval (CI)], 95%-99%) would have genetic testing to reduce the risk of dying of colorectal cancer in the best scenario (no false negatives, results disclosed to primary care physician). Only 41% (95% CI, 25%-57%) would have genetic testing in the worst case (20% false negatives, results disclosed to insurance company).

CONCLUSIONS

. Given the characteristics and levels included in the choice, if false-negative test results are unlikely and results are shared with a primary care physician, the majority would have genetic testing. As genomic services become widely available, primary care professionals will need to be increasingly knowledgeable about genetic testing decisions.