RESUMEN
During the training workshop on Inspection of Blood Establishments, which was hosted by the PEI GHPP BloodTrain in Harare from the 20th to the 24th of May 2019, participants from the National Regulatory Authorities from seven Sub-Sahara African countries presented their current experiences related to regulation and inspection of blood establishments in their respective countries. While in all seven countries regulation and inspection of conventional medicinal products manufacturer is performed, the regulatory situation of blood and blood components as well as inspection of blood establishments is still heterogeneous.
Asunto(s)
Bancos de Muestras Biológicas/normas , Bancos de Sangre/normas , Recolección de Muestras de Sangre/normas , Regulación y Control de Instalaciones/normas , Regulación Gubernamental , Manejo de Especímenes/normas , África del Sur del Sahara , Bancos de Muestras Biológicas/legislación & jurisprudencia , Bancos de Sangre/legislación & jurisprudencia , Transfusión de Componentes Sanguíneos/legislación & jurisprudencia , Transfusión de Componentes Sanguíneos/normas , Transfusión Sanguínea/legislación & jurisprudencia , Transfusión Sanguínea/normas , Regulación y Control de Instalaciones/legislación & jurisprudencia , Humanos , Control de Calidad , ZimbabweRESUMEN
GBPs are essential for immunity against intracellular pathogens, especially for Toxoplasma gondii control. Here, the molecular interactions of murine GBPs (mGBP1/2/3/5/6), homo- and hetero-multimerization properties of mGBP2 and its function in parasite killing were investigated by mutational, Multiparameter Fluorescence Image Spectroscopy, and live cell microscopy methodologies. Control of T. gondii replication by mGBP2 requires GTP hydrolysis and isoprenylation thus, enabling reversible oligomerization in vesicle-like structures. mGBP2 undergoes structural transitions between monomeric, dimeric and oligomeric states visualized by quantitative FRET analysis. mGBPs reside in at least two discrete subcellular reservoirs and attack the parasitophorous vacuole membrane (PVM) as orchestrated, supramolecular complexes forming large, densely packed multimers comprising up to several thousand monomers. This dramatic mGBP enrichment results in the loss of PVM integrity, followed by a direct assault of mGBP2 upon the plasma membrane of the parasite. These discoveries provide vital dynamic and molecular perceptions into cell-autonomous immunity.
Asunto(s)
Proteínas de Unión al GTP/metabolismo , Toxoplasma/inmunología , Toxoplasma/fisiología , Animales , Membrana Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Transferencia Resonante de Energía de Fluorescencia , Ratones , Microscopía , Imagen Óptica , Multimerización de Proteína , Espectrometría por Rayos X , Toxoplasma/efectos de los fármacos , Vacuolas/parasitologíaRESUMEN
IFN-γ orchestrates the host response against intracellular pathogens. Members of the guanylate binding proteins (GBP) comprise the most abundant IFN-γ-induced transcriptional response. mGBPs are GTPases that are specifically up-regulated by IFN-γ, other proinflammatory cytokines, toll-like receptor agonists, as well as in response to Listeria monocytogenes and Toxoplasma gondii infection. mGBP2 localizes at the parasitophorous vacuole (PV) of T. gondii; however, the molecular function of mGBP2 and its domains in T. gondii infection is not known. Here, we show that mGBP2 is highly expressed in several cell types, including T and B cells after stimulation. We provide evidence that the C-terminal domain is sufficient and essential for recruitment to the T. gondii PV. Functionally, mGBP2 reduces T. gondii proliferation because mGBP2-deficient cells display defects in the replication control of T. gondii. Ultimately, mGBP2-deficient mice reveal a marked immune susceptibility to T. gondii. Taken together, mGBP2 is an essential immune effector molecule mediating antiparasitic resistance.
