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The development of technologies for the biopreservation of infectious organisms requires careful analysis of benefits and risks. This article reviews the regulatory landscape and oversight responsibilities in the United States in respect to pathogen biopreservation. Focused on two globally significant pathogens, Cryptosporidium and Plasmodium , the article explores advantages and potential risks of biopreservation concerning biosafety, biosecurity and biocontainment. [ABSTRACT FROM AUTHOR]

Earth's biodiversity is increasingly threatened and at risk. We propose a passive lunar biorepository for long-term storage of prioritized taxa of live cryopreserved samples to safeguard Earth's biodiversity and to support future space exploration and planet terraforming. Our initial focus will be on cryopreserving animal skin samples with fibroblast cells. An exemplar system has been developed using cryopreserved fish fins from the Starry Goby, Asterropteryx semipunctata. Samples will be expanded into fibroblast cells, recryopreserved, and then tested in an Earth-based laboratory for robust packaging and sensitivity to radiation. Two key factors for this biorepository are the needs to reduce damage from radiation and to maintain the samples near –196° Celsius. Certain lunar sites near the poles may meet these criteria. If possible, further testing would occur on the International Space Station prior to storage on the Moon. To secure a positive shared future, this is an open call to participate in this decades-long program. [ABSTRACT FROM AUTHOR]

A lipid blend solution comprised of mono- and diglycerides is deposited onto an aqueous surface to generate synthetic neutral lipid droplets (SNLDs), which might have function other than energy storage molecules in Plasmodium falciparum during the intraerythrocytic stage of the parasite life cycle. The results indicated that neutral lipid structures within the digestive vacuole are not only the location of in vivo hemozoin formation but is also essential for the survival of the parasite by functioning as a kinetically competent and site specific mediator for heme detoxification.

Cryptosporidiosis in an enteric infection caused by Cryptosporidium parasites and is a major cause of acute infant diarrhea in the developing world. A major bottleneck to research progress is the lack of methods to cryopreserve Cryptosporidium oocysts, thus requiring routine propagation in laboratory animals. Here, we report a method to cryopreserve C. parvum oocysts by ultra-fast cooling. Cryopreserved oocysts exhibit high viability and robust in vitro excystation, and are infectious to interferon-γ knockout mice. The course of the infection is comparable to what we observe with unfrozen oocysts. Oocyst viability and infectivity is not visibly changed after several weeks of cryogenic storage. Cryopreservation will facilitate the sharing of oocysts from well-characterized isolates and transgenic strains among different laboratories. Research on Cryptosporidium parasites, a major cause of acute infant diarrhea, is hampered by the short shelf life of oocysts, thus requiring routine propagation in laboratory animals. Here, the authors report a method to cryopreserve viable and infectious Cryptosporidium oocysts by ultra-fast cooling. [ABSTRACT FROM AUTHOR]

The protozoan parasite responsible for malaria affects over 500 million people each year. Current antimalarials have experienced decreased efficacy due to the development of drug-resistant strains of Plasmodium spp., resulting in a critical need for the discovery of new antimalarials. Hemozoin, a crystalline by-product of heme detoxification that is necessary for parasite survival, serves as an important drug target. The quinoline antimalarials, including amodiaquine and chloroquine, act by inhibiting the formation of hemozoin. The formation of this crystal does not occur spontaneously, and recent evidence suggests crystallization occurs in the presence of neutral lipid particles located in the acidic digestive vacuole of the parasite. To mimic these conditions, the lipophilic detergent NP-40 has previously been shown to successfully mediate the formation of β-hematin, synthetic hemozoin. Here, an NP-40 detergent-based assay was successfully adapted for use as a high-throughput screen to identify inhibitors of β-hematin formation. The resulting assay exhibited a favorable Z' of 0.82 and maximal drift of less than 4%. The assay was used in a pilot screen of 38,400 diverse compounds at a screening concentration of 19.3 μM, resulting in the identification of 161 previously unreported β-hematin inhibitors. Of these, 48 also exhibited ≥ 90% inhibition of parasitemia in a Plasmodium falciparum whole-cell assay at a screening concentration of 23 μM. Eight of these compounds were identified to have nanomolar 50% inhibitory concentration values near that of chloroquine in this assay.

The growing drug resistance of Plasmodia spp. to current antimalarial agents in the quinine and artemisinin families further asserts the need for novel drug classes to combat malaria infection. One approach to the discovery of new antimalarials is the screening of natural product extracts for activity against the formation of hemozoin, a biomineral essential to parasite survival. By mimicking the in vivo lipid-water interface at which native hemozoin is found, hemozoin can be synthesized outside the parasite. In this work, a variety of lipophilic mediators was used to determine the optimal platform for in vitro hemozoin formation and then tested for efficacy in preliminary screens containing crude natural product extracts. The complete optimization and validation of a NP-40 detergent-mediated assay provide a screening template with an expedited 4-hour incubation time and identical IC50 values to those measured from the parasite's native lipid component.