Building the foundation for a community-generated national research blueprint for inherited bleeding disorders: research priorities to transform the care of people with hemophilia.

BACKGROUND: Decades of research have transformed hemophilia from severely limiting children's lives to a manageable disorder compatible with a full, active life, for many in high-income countries. The direction of future research will determine whether exciting developments truly advance health equity for all people with hemophilia (PWH). National Hemophilia Foundation (NHF) and American Thrombosis and Hemostasis Network conducted extensive inclusive all-stakeholder consultations to identify the priorities of people with inherited bleeding disorders and those who care for them. RESEARCH DESIGN AND METHODS: Working group (WG) 1 of the NHF State of the Science Research Summit distilled the community-identified priorities for hemophilia A and B into concrete research questions and scored their feasibility, impact, and risk. RESULTS: WG1 defined 63 top priority research questions concerning arthropathy/pain/bone health, inhibitors, diagnostics, gene therapy, the pediatric to adult transition of care, disparities faced by the community, and cardiovascular disease. This research has the potential to empower PWH to thrive despite lifelong comorbidities and achieve new standards of wellbeing, including psychosocial. CONCLUSIONS: Collaborative research and care delivery will be key to capitalizing on current and horizon treatments and harnessing technical advances to improve diagnostics and testing, to advance health equity for all PWH.

Hemophilia is the best known of the inherited bleeding disorders (BD). This is a rare condition that causes disproportionate bleeding, often into joints and vital organs. Factor replacement, injecting recombinant or plasma-based clotting factor products directly into the vein, became commonplace to control the disorder in the 1990s and 2000s. Prophylaxis, or injecting replacement factor every few days into people with hemophilia (PWH), has revolutionized patients' lives. In the last few years, other advances in new therapies have entered this space, such as non-factor replacement therapies and gene therapy. With many more research advances on the horizon, the National Hemophilia Foundation (NHF) initiated a State of the Science Research Summit in 2020. This event was attended by over 880 interested parties to help design an agenda of research priorities for inherited BDs for the next decade, based on community consultations. NHF formed multiple Working Groups (WG), each exploring a theme resulting from the community consultations, and presenting their results at the Summit. Led by 2 hematologists who manage and treat PWH daily, the 21-community member WG1 assigned to hemophilia A and B divided into 7 subgroups to identify and organize research priorities for different topic areas. The outcomes focused on prioritizing patients' needs, technological advances, and research in the areas of greatest potential for PWH and those who care for them. The results are a roadmap for the future execution of a research plan that truly serves the community.

Performance Evaluation of a Prototype Architect Antibody Assay for Babesia microti.

The tick-borne protozoan Babesia microti is responsible for more than 200 cases of transfusion-transmitted babesiosis (TTB) infection in the United States that have occurred over the last 30 years. Measures to mitigate the risk of TTB include nucleic acid testing (NAT) and B. microti antibody testing. A fully automated prototype B. microti antibody test was developed on the Architect instrument. The specificity was determined to be 99.98% in volunteer blood donors (n = 28,740) from areas considered to have low endemicity for B. microti The sensitivity of the prototype test was studied in experimentally infected macaques; a total of 128 samples were detected as positive whereas 125 were detected as positive with an indirect fluorescent antibody (IFA) test; additionally, 83 (89.2%) of the PCR-positive samples were detected in contrast to 81 (87.1%) using an IFA test. All PCR-positive samples that tested negative in the prototype antibody test were preseroconversion period samples. Following seroconversion, periods of intermittent parasitemia occurred; 17 PCR-negative samples drawn in between PCR-positive bleed dates tested positive both by the prototype test (robust reactivity) and IFA test (marginal reactivity) prior to the administration of therapeutic drugs, indicating that the PCR test failed to detect samples from persistently infected macaques. The prototype assay detected 56 of 58 (96.6%) human subjects diagnosed with clinical babesiosis by both PCR and IFA testing. Overall, the prototype anti-Babesia assay provides a highly sensitive and specific test for the diagnosis of B. microti infection. While PCR is preferred for detection of window-period parasitemia, antibody tests detect infected subjects during periods of low-level parasitemia.

Understanding interactions between immunoassay excipient proteins and surfactants at air-aqueous interface.

Air-aqueous interfacial properties of four excipient proteins commonly used in immunoassay reagent formulations were studied with shear rheology and surface characterization methods. A Du Noüy ring geometry was utilized to quantify the elastic (G') and viscous (G″) shear moduli of protein interfacial networks and to probe the effect of several nonionic surfactants at various concentrations. Time sweep protocols of buffered protein solutions yielded G' in the range of 16 mN/m for bovine serum albumin (BSA), 6 mN/m for bovine gamma globulin (BGG), 7 mN/m for Mouse IgG, and 0.9 mN/m for sodium caseinate. G's were higher than G″s for a given protein. Effect of nonionic surfactants on G' of a protein was concentration dependent and the magnitude of protein displacement from the interface varied with Tween 20>Triton X-100>Triton X-405, with the exception of Mouse IgG. Degree of displacement of BSA from the interface by Tween 20 was approximately 66-fold greater than that of BGG whose displacement by Tween 20 was approximately 7-fold greater than that of Mouse IgG. Degree of displacement by Triton X-100 was comparable in case of studied proteins. Surface tension characterization suggests that the interfacial interactions between proteins and surfactants are driven not only by their surface activity but also by the network formation abilities of the proteins. Data presented here demonstrates a potential application of interfacial studies to sensitively identify discriminatory interactions between proteins and surfactants in immunoassay solutions.

Development of a fluorescence resonance energy transfer peptide library technology for detection of protease contaminants in protein-based raw materials used in diagnostic assays.

Protease impurities in raw materials used in enzyme immunoassays can impair assay performance. This risk may be greatly decreased if incoming protein-based raw materials are controlled for protease impurities or if protease inhibitors are used in the assay formulations. As many different proteases might occur in protein raw materials, it is desirable to have a general test for protease contamination. With the help of a fluorescence resonance energy transfer peptide library containing about 2.5 million peptides, we have succeeded in establishing such a system, with sensitivity in the nanogram range for known proteases. Protease contamination was found to differ between different raw materials and was correlated with assay performance. Protease activity in contaminated raw materials could be suppressed to various degrees with different chemical inhibitors or by thermal treatment. This technology is suited for the control of incoming protein-based raw materials used for enzyme immunoassays, as well as for the optimization of the use of protein inhibitors or thermal treatment of protein-based raw materials for the inactivation of proteases.

HIV/STI Risk behaviors among Latino migrant workers in New Orleans post-Hurricane Katrina disaster.

OBJECTIVES: A rapid influx of Latino migrant workers came to New Orleans after Hurricane-Katrina. Many of these men were unaccompanied by their primary sex partner potentially placing them at high-risk for HIV/STIs. The purpose of this study was to assess HIV/STI sexual risk behavior of these men. METHODS: A venue-based sample of Latinos who came to New Orleans post-Hurricane Katrina were administered an anonymous, structured interview in Spanish in a mobile unit and urine tested for Chlamydia trachomatis (CT) and Neisseria gonorrhea (GC) using the nucleic acid amplification technique. RESULTS: Participants (n = 180) had a mean age of 33 (range, 18-79), did not speak or understand English very well (93.9%), were undocumented (91.2%), were married (63.5%), and had children (67.4%), though the percent living with spouse and children was 6.1% and 4.9%, respectively. Although most men were born in Honduras (49.7%) and Mexico (25.4%), 61.9% came to New Orleans from another US state. The majority drank alcohol in the past week (75.5%), and of those, 68.7% engaged in binge drinking. A lower percentage used marijuana (16.6%) and cocaine (5.5%) at least once in the prior week. No men reported injection drug use. Self-reported history of HIV was 10%. No men tested positive for GC and 5 (2.8%) tested positive for CT. In the last month, 68.9% engaged in sex with high-risk sex partners, 30.0% were in potential bridge position, 50.0% used condoms inconsistently, 30.6% did not use a condom the last time they had sex, and 21.1% were abstinent. Since arriving, 9.4% reported leaving and returning to New Orleans. CONCLUSION: Latino migrant workers in New Orleans reported risky sexual behaviors and low condom use within a potential bridge position. Although a low prevalence of CT and GC was found, there was a high percent of self-reported HIV infection. The cultural and contextual factors that place these migrant workers and their sex partner(s) at risk for HIV/STI need further investigation.

Synchrotron X-ray fluorescence and trace metals in the cementum rings of human teeth.

Synchrotron micro X-ray fluorescence has been used to study differences in the trace element concentration between the dentine and cementum rings of human teeth. The results show that metals such as zinc are concentrated in the cementum rings. This suggests that if the rings are deposited annually a temporal record of metal exposure may be extracted from this material.