In vitro culture of Plasmodium berghei-ANKA maintains infectivity of mouse erythrocytes inducing cerebral malaria

<p>Abstract</p> <p>Background</p> <p>Infection with <it>Plasmodium berghei </it>is a widely used model of murine malaria and a powerful tool for reverse genetic and pathogenesis studies. However, the efficacy of <it>in vitro </it>reinvasion of erythrocytes is generally low, limiting <it>in vitro </it>studies.</p> <p>Methods</p> <p><it>Plasmodium berghei </it>ANKA-infected blood obtained from a susceptible infected mouse was cultured in various conditions and <it>in vitro </it>parasitaemia was measured every day to evaluate the rate of reinvasion.</p> <p>Results</p> <p>High quality culture media were used and reinvasion rates were improved by vigorous orbital shaking of the flask and increasing density of the medium with gelatin.</p> <p>Discussion</p> <p>Using these settings, reinvasion of normal mouse erythrocytes by the parasite was obtained <it>in vitro </it>over two weeks with preservation of the infectivity <it>in vivo</it>.</p

Potent Neutralization of Influenza A Virus by a Single-Domain Antibody Blocking M2 Ion Channel Protein

Influenza A virus poses serious health threat to humans. Neutralizing antibodies against the highly conserved M2 ion channel is thought to offer broad protection against influenza A viruses. Here, we screened synthetic Camel single-domain antibody (VHH) libraries against native M2 ion channel protein. One of the isolated VHHs, M2-7A, specifically bound to M2-expressed cell membrane as well as influenza A virion, inhibited replication of both amantadine-sensitive and resistant influenza A viruses in vitro, and protected mice from a lethal influenza virus challenge. Moreover, M2-7A showed blocking activity for proton influx through M2 ion channel. These pieces of evidence collectively demonstrate for the first time that a neutralizing antibody against M2 with broad specificity is achievable, and M2-7A may have potential for cross protection against a number of variants and subtypes of influenza A viruses

Experimental Observation of Proton Bunch Modulation in a Plasma at Varying Plasma Densities

We give direct experimental evidence for the observation of the full transverse self-modulation of a long, relativistic proton bunch propagating through a dense plasma. The bunch exits the plasma with a periodic density modulation resulting from radial wakefield effects. We show that the modulation is seeded by a relativistic ionization front created using an intense laser pulse copropagating with the proton bunch. The modulation extends over the length of the proton bunch following the seed point. By varying the plasma density over one order of magnitude, we show that the modulation frequency scales with the expected dependence on the plasma density, i.e., it is equal to the plasma frequency, as expected from theory