A rhoptry antigen of Plasmodium falciparum is protective in Saimiri monkeys

A non-polymorphic antigen associated with the rhoptry organelles of Plasmodium falciparum has been purified by immuno-affinity chromatography. The antigen, RAP-1 (rhoptry associated protein-1). which is defined by monoclonal antibodies which inhibit parasite growth in vitro, is a multi-component antigen consisting of four major proteins of 80, 65, 42 and 40 kDa and two minor proteins of 77 and 70 kDa. These proteins were electro-eluted from preparative sodium dodecyl sulphate polyacrylamide gels and protected Saimiri sciureus monkeys from a lethal blood-stage infection of P. falciparum malaria. Sera from the protected animals recognized only proteins of the RAP-1 antigen when used to probe a Western blot of total parasite protein extract, confirming that RAP-1 is responsible for eliciting the protective immune respons

The association of p16INK4A and fragile histidine triad gene expression and cervical lesions

Objective. This cross-sectional study was intended to assess the association between immunohistochemical analysis of p16INK4A and fragile histidine triad (FHIT) and the presence of precancerous cervical lesions. Materials and Methods. Women seen at Pe´ rola Byington Hospital, São Paulo, Brazil, with histologically confirmed cervicitis (n = 31), cervical intraepithelial neoplasia (CIN) 1 (n = 30), CIN 2,3 (n = 30), and cervical cancer (n = 7) had also cervical material collected for liquid-based cytology, human papillomavirus Hybrid Capture 2 (HC2) test, and p16 and FHIT immunohistochemical reactions. Results. p16 and FHIT reactions were scored as the following: G1%, 1% to 5%, 95% to 25%, and 925%. Receiver operating curve analysis was used to select p16 and FHIT score cutoffs for further categorical analyses. All but one of the 37 CIN 2,3/cancer cases had a p16 score of greater than 1% to 5%. Among the 61 cervicitis/CIN 1 cases, 46 (75%) had a p16 score lower than 1% to 5%. In contrast, no association of FHIT expression and severity of cervical lesions could be demonstrated in this data set. Receiver operating curve analyses suggested the score of 1% to 5% for p16 as the cutoff that best discriminates CIN 2,3/cancer from cervicitis/CIN 1. No cutoff for FHIT scores could be suggested with data set. Conclusions. p16, but not FHIT expression, has the potential to be used as complementary diagnostic tool to investigate human papillomavirusYinduced cervical lesions, if these results are confirmed in larger studies.(undefined

Biomolecular Condensates in Cell Biology and Virology: Phase-Separated Membraneless Organelles (MLOs)

Membraneless organelles (MLOs) in the cytoplasm and nucleus in the form of 2D and 3D phase-separated biomolecular condensates are increasingly viewed as critical in regulating diverse cellular functions. These functions include cell signaling, immune synapse function, nuclear transcription, RNA splicing and processing, mRNA storage and translation, virus replication and maturation, antiviral mechanisms, DNA sensing, synaptic transmission, protein turnover and mitosis. Components comprising MLOs often associate with low affinity; thus cell integrity can be critical to the maintenance of the full complement of respective MLO components. Phase-separated condensates are typically metastable (shape-changing) and can undergo dramatic, rapid and reversible assembly and disassembly in response to cell signaling events, cell stress, during mitosis, and after changes in cytoplasmic crowding (as observed with condensates of the human myxovirus resistance protein MxA). Increasing evidence suggests that neuron-specific aberrations in phase-separation properties of RNA-binding proteins (e.g. FUS and TDP-43) and others (such as the microtubule-binding protein tau) contribute to the development of degenerative neurological diseases (e.g. amyotrophic lateral sclerosis, frontotemporal lobar degeneration, and Alzheimer\u27s disease). Thus, studies of liquid-like phase separation (LLPS) and the formation, structure and function of MLOs are of considerable importance in understanding basic cell biology and the pathogenesis of human diseases

Biomolecular condensates in cell biology and virology: Phase-separated membraneless organelles (MLOs)

Membraneless organelles (MLOs) in the cytoplasm and nucleus in the form of 2D and 3D phase-separated biomolecular condensates are increasingly viewed as critical in regulating diverse cellular functions. These functions include cell signaling, immune synapse function, nuclear transcription, RNA splicing and processing, mRNA storage and translation, virus replication and maturation, antiviral mechanisms, DNA sensing, synaptic transmission, protein turnover and mitosis. Components comprising MLOs often associate with low affinity; thus cell integrity can be critical to the maintenance of the full complement of respective MLO components. Phase-separated condensates are typically metastable (shape-changing) and can undergo dramatic, rapid and reversible assembly and disassembly in response to cell signaling events, cell stress, during mitosis, and after changes in cytoplasmic crowding (as observed with condensates of the human myxovirus resistance protein MxA). Increasing evidence suggests that neuron-specific aberrations in phase-separation properties of RNA-binding proteins (e.g. FUS and TDP-43) and others (such as the microtubule-binding protein tau) contribute to the development of degenerative neurological diseases (e.g. amyotrophic lateral sclerosis, frontotemporal lobar degeneration, and Alzheimer\u27s disease). Thus, studies of liquid-like phase separation (LLPS) and the formation, structure and function of MLOs are of considerable importance in understanding basic cell biology and the pathogenesis of human diseases