Gene therapy: charting a future course--summary of a National Institutes of Health Workshop, April 12, 2013.

Recently, the gene therapy field has begun to experience clinical successes in a number of different diseases using various approaches and vectors. The workshop Gene Therapy: Charting a Future Course, sponsored by the National Institutes of Health (NIH) Office of Biotechnology Activities, brought together early and mid-career researchers to discuss the key scientific challenges and opportunities, ethical and communication issues, and NIH and foundation resources available to facilitate further clinical advances.

Tuskegee Bioethics Center 10th anniversary presentation: "Commemorating 10 years: ethical perspectives on origin and destiny".

More than 70 years have passed since the beginning of the Public Health Service syphilis study in Tuskegee, Alabama, and it has been over a decade since President Bill Clinton formally apologized for it and held a ceremony for the Tuskegee study participants. The official launching of the Tuskegee University National Center for Bioethics in Research and Health Care took place two years after President Clinton's apology. How might we fittingly discuss the Center's 10th Anniversary and the topic 'Commemorating 10 Years: Ethical Perspectives on Origin and Destiny'? Over a decade ago, a series of writers, many of them African Americans, wrote a text entitled 'African-American Perspectives on Biomedical Ethics'; their text was partly responsible for a prolonged reflection by others to produce a subsequent work, 'African American Bioethics: Culture, Race and Identity'.

Purification of C1 inhibitor. A new approach for the isolation of this biologically important plasma protease inhibitor.

C1 inhibitor (C1-INH) acts to inhibit active enzymes of both the classical complement and Hageman factor-dependent pathways. Previously reported C1-INH purification procedures were multistep and most have been associated with significant loss in specific functional activity. We have developed a simple chromatographic procedure which yields a pure C1-INH protein from normal human plasma with a specific activity equal to or greater than the starting sample.

Immunodiffusion assay of C1 inhibitor function in serum: prospective analysis in angioedema-urticaria.

An immunodiffusion assay for detecting C1 inhibitor function in human serum was described recently by Ziccardi and Cooper. In our present study, the applicability of this assay for C1 inhibitor deficiency or C1 inhibitor dysfunction was evaluated. Of the 39 patients evaluated, all eight patients with the common (C1 inhibitor deficiency) form of hereditary angioedema and all three patients with the variant (dysfunctional C1 inhibitor) form of hereditary angioedema were identified correctly.

Prekallikrein activation and high-molecular-weight kininogen consumption in hereditary angioedema.

Patients with hereditary angioedema lack C-1 inhibitor, a plasma alpha 2-glycoprotein that inhibits both the proteolytic action of C1, the activated first component of the complement system, and the activity of components of the contact phase of coagulation: kallikrein, factor XIa, and factor XIIa. Such patients have been shown to have low levels of C4 and C2, the natural substrates for C-1, but the levels were not correlated with the presence of symptoms. We studied three patients with angioedema for evidence of activation of the contact system and found that during a symptomatic period they had decreased levels of prekallikrein, a substrate for the activated forms of factor XII, and reductions in high-molecular-weight kininogen, a substrate for plasma kallikrein.

Detection of active kallikrein in induced blister fluids of hereditary angioedema patients.

Six suction-induced blister fluids obtained from five patients with hereditary angioedema (HAE) contained active kallikrein, whereas only two blister fluids obtained from eight normal volunteers contained small amounts of this activity. Kallikrein was present in large amounts of HAE blister fluids as assessed by its ability to liberate smooth-muscle-contracting activity from purified high molecular weight kininogen. It was inhibited by purified antibodies specific for plasma prekallikrein and also by purified C1 inhibitor, but not by antibodies specific for C1s.