Biology subjects

Martinez-Sobrido, L.

Publications and source records attributed to Martinez-Sobrido, L..

75 records · Page 5Linked to original sources

bioRxiv2020

A broad and potent H1-specific human monoclonal antibody produced in plants prevents influenza virus infection and transmission in guinea pigs

Although seasonal influenza vaccines block most predominant influenza types and subtypes, humans still remain vulnerable to waves of seasonal and new potential pandemic influenza viruses for which no immunity may exist because of viral antigenic drift and/or shift, respectively. Previously, we have described a human monoclonal antibody (hMAb), KPF1, which was produced in human embryonic kidney 293T cells (KPF1-HEK) with broad and potent neutralizing activity against H1N1 influenza A viruses (IAV) in vitro, and prophylactic and therapeutic activities in vivo. In this study, we produced hMAb KPF1 in tobacco plants (KPF1-Antx) and demonstrate how the plant-produced KPF1-Antx hMAb possesses similar biological activity compared with the mammalian produced KPF1-HEK hMAb. KPF1-Antx hMAb shows broad binding to recombinant HA proteins and H1N1 IAV, including A/California/04/2009 (pH1N1) in vitro, that are comparable to those observed with KPF1-HEK hMAb. Importantly, prophylactic administration of KPF1-Antx hMAb to guinea pigs prevented pH1N1 infection and transmission in both prophylactic and therapeutic experiments, substantiating its clinical potential to prevent and treat H1N1 infections. Collectively, this study demonstrates, for the first time, that plant-produced influenza hMAbs have similar in vitro and in vivo biological properties to those produced in mammalian cells. Because of the many advantages of plant-produced hMAbs, such as rapid batch production, low cost, and the absence of mammalian cell products, they represent an alternative strategy for the production of immunotherapeutics for the treatment of influenza viral infections, including emerging seasonal and/or pandemic strains.

immunology↗

bioRxiv2019

Snake deltavirus utilizes envelope proteins of different viruses to generate infectious particles

Hepatitis D virus (HDV) is the only known human satellite virus, and it requires hepatitis B virus (HBV) to form infectious particles. Until 2018 HDV was the sole representative of the genus Deltavirus. The subsequent identification of HDV-like agents in non-human hosts indicated a much longer evolutionary history of deltaviruses than previously hypothesized. Interestingly, none of the HDV-like agents were found in co-infection with an HBV-like agent suggesting that these viruses use different helper virus(es). Here we show, using snake deltavirus (SDeV), that HBV represents only a single example of helper viruses for deltaviruses. We cloned the SDeV genome into a mammalian expression plasmid, and by transfection could initiate SDeV replication in cultured snake and mammalian cells. By superinfecting SDeV infected cells with arenaviruses, or by transfecting different viral surface proteins, we could induce infectious SDeV particle production. Our findings indicate that deltaviruses can likely use a multitude of helper viruses or even viral glycoproteins to form infectious particles. Persistent and recurrent infections would be beneficial for the spread of deltaviruses. It seems plausible that new human and veterinary disease associations with deltavirus infections will be identified in the future.

microbiology↗

bioRxiv2019

Influenza Viruses in Mice: Deep Sequencing Analysis of Serial Passage and Effects of Sialic Acid Structural Variation

Influenza A viruses have regularly jumped to new hosts to cause epidemics or pandemics, an evolutionary process that involves variation in the viral traits necessary to overcome host barriers and facilitate transmission. Mice are not a natural host for influenza virus, but are frequently used as models in studies of pathogenesis, often after multiple passages to achieve higher viral titers that result in clinical disease such as weight loss or death. Here we examine the processes of influenza A virus infection and evolution in mice by comparing deep sequence variation of a human H1N1 pandemic virus, a seasonal H3N2 virus, and a H3N2 canine influenza virus during experimental passage. We also compared replication and sequence variation in wild-type mice expressing N-glycolylneuraminic acid (Neu5Gc) with that seen in mice expressing only N-acetylneuraminic acid (Neu5Ac). Viruses derived from plasmids were propagated in MDCK cells and then passaged in mice up to four times. Full genome deep sequencing of the plasmids, cultured viruses, and viruses from mice at various passages revealed only small numbers of mutational changes. The H3N2 canine influenza virus showed increases in frequency of sporadic mutations in the PB2, PA, and NA segments. The H1N1 pandemic virus grew well in mice, and while it exhibited the maintenance of some minority mutations, there was no clear adaptive evolution. The H3N2 seasonal virus did not establish in the mice. Finally, there were no clear sequence differences associated with the presence or absence of Neu5Gc.\n\nSIGNIFICANCEMice are commonly used as a model to study the growth and virulence of influenza A viruses in mammals, but are not a natural host and have distinct sialic acid receptor profiles compared to humans. Using experimental infections with different subtypes of influenza A virus derived from different hosts we found that evolution of influenza A virus in mice did not necessarily proceed through the linear accumulation of host-adaptive mutations, that there was variation in the patterns of mutations detected in each repetition, and the mutation dynamics depended on the virus examined. In addition, variation in the viral receptor, sialic acid, did not effect influenza evolution in this model. Overall this shows that mice provide a useful animal model for influenza, but that host passage evolution will vary depending on the virus being tested.

microbiology↗