Differential roles of an Anopheline midgut GPI-anchored protein in mediating Plasmodium falciparum and Plasmodium vivax ookinete invasion.

Novel strategies to directly thwart malaria transmission are needed to maintain the gains achieved by current control measures. Transmission-blocking interventions (TBIs), namely vaccines and drugs targeting parasite or mosquito molecules required for vector-stage parasite development, have been recognized as promising approaches for preventing malaria transmission. However, the number of TBI targets is limited and their degree of conservation among the major vector-parasite systems causing human disease is unclear. Therefore, discovery and characterization of novel proteins involved in vector-stage parasite development of Plasmodium falciparum and Plasmodium vivax is paramount. We mined the recent Anopheles gambiae midgut lipid raft proteome for putative mosquito-derived TBI targets and characterized a secreted glycoconjugate of unknown function, AgSGU. We analyzed molecular variation in this protein among a range of anopheline mosquitoes, determined its transcriptomic and proteomic profiles, and conducted both standard and direct membrane feeding assays with P. falciparum (lab/field) and P. vivax (field) in An. gambiae and Anopheles dirus. We observed that α-AgSGU antibodies significantly reduced midgut infection intensity for both lab and field isolates of P. falciparum in An. gambiae and An. dirus. However, no transmission-reducing effects were noted when comparable concentrations of antibodies were included in P. vivax-infected blood meals. Although antibodies against AgSGU exhibit transmission-reducing activity, the high antibody titer required for achieving 80% reduction in oocyst intensity precludes its consideration as a malaria mosquito-based TBI candidate. However, our results suggest that P. falciparum and P. vivax ookinetes use a different repertoire of midgut surface glycoproteins for invasion and that α-AgSGU antibodies, as well as antibodies to other mosquito-midgut microvillar surface proteins, may prove useful as tools for interrogating Plasmodium-mosquito interactions.

Antibodies to a single, conserved epitope in Anopheles APN1 inhibit universal transmission of Plasmodium falciparum and Plasmodium vivax malaria.

Malaria transmission-blocking vaccines (TBVs) represent a promising approach for the elimination and eradication of this disease. AnAPN1 is a lead TBV candidate that targets a surface antigen on the midgut of the obligate vector of the Plasmodium parasite, the Anopheles mosquito. In this study, we demonstrated that antibodies targeting AnAPN1 block transmission of Plasmodium falciparum and Plasmodium vivax across distantly related anopheline species in countries to which malaria is endemic. Using a biochemical and immunological approach, we determined that the mechanism of action for this phenomenon stems from antibody recognition of a single protective epitope on AnAPN1, which we found to be immunogenic in murine and nonhuman primate models and highly conserved among anophelines. These data indicate that AnAPN1 meets the established target product profile for TBVs and suggest a potential key role for an AnAPN1-based panmalaria TBV in the effort to eradicate malaria.

Emphasizing Public Health Within a Health Information Exchange: An Evaluation of the District of Columbia's Health Information Exchange Program.

INTRODUCTION: Clinovations Government Solutions (CGS) was contracted in 2013 to conduct a mixed-methods evaluation of the District of Columbia (D.C.) Health Information Exchange (HIE) program as part of their Cooperative Agreement Grant funded by the Office of the National Coordinator in 2010. The evaluation was to focus on the progress of the HIE, how many providers and hospitals were participating in the program, and what benefits were being realized through the use of the HIE. During the course of the evaluation, the CGS team found that the use of the HIE to support public health reporting was one of its core elements. BACKGROUND: The D.C. HIE is one of 56 HIE that were funded out of the Cooperative Agreement program. The HIE program was managed by the District of Columbia Department of Health Care Finance (DHCF), which also manages the District of Columbia Medicaid Program. The program was initially designed to accomplish the following: developing state-level directories and enabling technical services for HIE within and across states; ensuring an effective model for governance and accountability; coordinating an integrated approach with Medicaid and public health; and developing or updating privacy and security requirements for HIE within and across state borders. As the evaluation progressed, the CGS team discovered that the relationship between the DHCF and the District of Columbia Department of Health (DOH) had become a cornerstone of the D.C. HIE program. METHODS: The CGS team used a mixed-methods approach for the evaluation, including a review of documents developed by the DHCF in its HIE program, including its original application. We also conducted 10 key informant interviews and moderated two small-group discussions using a semistructured protocol; and we developed a survey that measured the use, satisfaction, and future sustainability of the HIE for over 200 providers within the District of Columbia. FINDINGS: While the evaluation focused on the D.C. HIE program in its entirety, the results indicated the value of utilizing the HIE for public health reporting to enhance the surveillance activities of the DOH. Specifically, the DHCF and DOH collaboration resulted in using the HIE to electronically capture and report immunization data; and in requiring electronic lab reporting and results as part of the Meaningful Use Requirement-which can assist in detecting HIV/AIDS and providing better care for the district's high population of individuals with HIV/AIDS. Electronic lab reporting and electronic prescribing within the HIE can assist the DOH and providers in identifying specific diseases, such as tuberculosis and viral hepatitis, before they affect a significant part of the population. DISCUSSION: Given the severe health disparities in the district, the ability of the D.C. HIE program to collect public health information on affected populations will be instrumental in better understanding and identifying methods of supporting these populations through improved surveillance and identification of the appropriate treatments. The D.C. HIE program is uniquely positioned to support these populations due to the partnership of DHCF with the D.C. DOH. CONCLUSION AND NEXT STEPS: The District of Columbia has made significant strides in expanding its public health infrastructure and activities. Three key areas of growth were identified that have the potential to transform the District of Columbia's public health approach: establishing sufficient feedback loops, collection of environmental data, integration, and interoperability.

Liver-targeting of primaquine-(poly-γ-glutamic acid) and its degradation in rat hepatocytes.

We have synthesized poly-γ-glutamic acid (PGA) modified with a synthetic trivalent glyco-ligand (TriGalNAc) for the hepatocyte asialoglycoprotein receptor (ASGP-R). We investigated in vivo distribution of unmodified PGA and TriGalNAc-modified PGA (TriGalNAc-PGA) in mice after intravenous injection. Most of unmodified PGA administered was transported to the bladder over 20-80min, suggesting a rapid excretion of unmodified PGA into urine. In contrast, TriGalNAc-PGA was found exclusively in the liver over the same period of time. We further synthesized TriGalNAc-PGA-primaquine conjugate (TriGalNAc-PGA-PQ), and investigated binding, uptake, and catabolism of the conjugate by rat hepatocytes. Our studies indicated that approximately 250ng per million cells of the conjugate bound to one million rat hepatocytes at 0°C, and approximately 2µg per million cells of the conjugate was taken up over 7h incubation at 37°C. Furthermore, our results suggested that TriGalNAc-PGA-PQ was almost completely degraded over 24h, and small degradation products were secreted into cell culture medium. The results described in this report suggest that the TriGalNAc ligand can serve as an excellent targeting device for delivery of PGA-conjugates to the liver hepatocytes, and rat hepatocytes possess sufficient capacity to digest PGA even modified with other substituents.