Baculovirus surface display of a chimeric E-NS1 protein of YFV protects against YFV infection.

Yellow fever (YF) is a disease caused by the homonymous flavivirus that can be prevented by a vaccine containing attenuated viruses. Since some individuals cannot receive this vaccine, the development of alternatives is desirable. Here, we developed a recombinant baculovirus (rBV) surface display platform utilizing a chimeric E-NS1 protein as a vaccine candidate. A pBacPAK9 vector containing the baculoviral GP64 signal peptide, the YFV prM, E, NS1 and the ectodomain of VSV-G sequences was synthesized. This transfer plasmid and the bAcGOZA bacmid were cotransfected into Sf9 cells, and an rBV-E-NS1 was obtained, which was characterized by PCR, WB, IFI and FACS analysis. Mice immunized with rBV-E-NS1 elicited a specific humoral and cellular immune response and were protected after YFV infection. In summary, we have developed an rBV that expresses YFV major antigen proteins on its surface, which opens new alternatives that can be tested in a mouse model.

Theiler's Murine Encephalomyelitis Virus Replicates in Primary Neuron Cultures and Impairs Spine Density Formation.

In this study, we examined infection with the highly neurovirulent GDVII, the less neurovirulent DA strains, and with a mutant DA, which lacks the L* protein (L*-1) involved in viral persistence and demyelinating disease, to analyze the direct effects of Theiler's murine encephalomyelitis virus (TMEV) replication using primary cultures of mouse brain hippocampal neurons. All viruses replicate in cultured neurons, with GDVII having the highest titers and L*-1 the lowest. Accordingly, all were positive for viral antigen staining 3 days postinfection (dpi), and DA and L*-1 were also positive after 12 dpi. NeuN + immunostaining showed an early and almost complete absence of positive cells in cultures infected with GDVII, an approximately 50% reduction in cultures infected with DA, and fewer changes in L*-1 strains at 3 dpi. Accordingly, staining with chloromethyltetramethylrosamine orange (Mitotracker OrangeTM) as a parameter for cell viability showed similar results. Moreover, at 1 dpi, the strain DA induced higher transcript levels of neuroprotective genes such as IFN-Iß, IRF7, and IRF8. At 3 dpi, strains GDVII and DA, but not the L*-1 mutant, showed lower PKR expression. In addition, confocal analysis showed that L*-1-infected neurons exhibited a decrease in spine density. Treatment with poly (I:C), which is structurally related to dsRNA and is known to trigger IFN type I synthesis, reduced spine density even more. These results confirmed the use of mouse hippocampal neuron cultures as a model to study neuronal responses after TMEV infection, particularly in the formation of spine density.

Tipos de spa no reportados en nuestro país en Staphylococcus aureus de pacientes adultos de un hospital escuela, Santa Fe, Argentina / Non reported spa types in our country in Staphylococcus aureus from adult patients of a school hospital, Santa Fe- Argentina

Staphylococcus aureus es un patógeno responsable de diversos cuadros clínicos. Los marcadores moleculares son útiles para el estudio de la epidemiología microbiana. Se estudiaron 22 aislamientos de S. aureus resistentes a meticilina (SARM) y 23 sensibles a meticilina (SASM) mediante mecA, cassette SCCmec, leucocidina de Panton Valentine (LPV) y polimorfismo spa; se analizaron datos de los pacientes. SASM predominó en muestras distintas de piel y partes blandas de internados, mientras SARM en partes blandas. Predominó el SCCmec tipo IV seguido del I. Se encontró baja presencia de LPV. En SARM hubo 11 tipos de spa diferentes, t019 fue el más frecuente y en pacientes ambulatorios. En SASM se hallaron 17 tipos con prevalencia del t189. El spa t002 estuvo presente en SASM y SARM. Se hallaron 11 tipos de spa no reportados en nuestro país.

Staphylococcus aureus is a pathogen associated a different kind of infection. Molecular markers are useful tools to study microbial epidemiology. Twenty two methicillin-resistant S. aureus (MRSA) and 23 methicillin-susceptible S. aureus (MSSA) were studied by mecA gene, SCCmec cassette, Panton Valentine leucocidin (PVL) and spa polymorphism. The clinical data patients were analyzed. MSSA was prevalent in samples different from skin and soft tissue (SST) and in hospitalized patients, whereas MRSA in SST. SCCmec type IV was predominant, followed spa; by type I. Low presence of PVL was found. In MRSA 11 different types of spa were detected, SCCmec; t019 was the most frequent and associated with outpatient, 17 types were found in MSSA and Panton Valentine t189 was prevalent. spa t002 was present in MSSA and MRSA. We found 11 types of spa not leucocidin reported in our country.

[Non reported spa types in our country in Staphylococcus aureus from adult patients of a school hospital, Santa Fe - Argentina]. / Tipos de spa no reportados en nuestro país en Staphylococcus aureus de pacientes adultos de un hospital escuela, Santa Fe, Argentina.

Staphylococcus aureus is a pathogen associated a different kind of infection. Molecular markers are useful tools to study microbial epidemiology. Twenty two methicillin-resistant S. aureus (MRSA) and 23 methicillin-susceptible S. aureus (MSSA) were studied by mecA gene, SCCmec cassette, Panton Valentine leucocidin (PVL) and spa polymorphism. The clinical data patients were analyzed. MSSA was prevalent in samples different from skin and soft tissue (SST) and in hospitalized patients, whereas MRSA in SST. SCCmec type IV was predominant, followed by type I. Low presence of PVL was found. In MRSA 11 different types of spa were detected, t019 was the most frequent and associated with outpatient, 17 types were found in MSSA and t189 was prevalent. spa t002 was present in MSSA and MRSA. We found 11 types of spa not reported in our country.