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Rothfuchs, A. G.

Publications and source records attributed to Rothfuchs, A. G..

2 recordsLinked to original sources

Vaccinia virus infection inhibits skin dendritic cell migration to draining lymph node

Despite the success of Vaccinia virus (VACV) against smallpox there remains a paucity of information on Dendritic cell (DC) responses to the virus, especially on the traffic of DCs and VACV to draining LN (dLN). Herein we studied skin DC migration in response to VACV and compared it to the tuberculosis vaccine Mycobacterium bovis Bacille Calmette-Guerin (BCG), another live-attenuated vaccine administered via the skin. In stark contrast to BCG, skin DCs did not relocate to dLN in response to VACV. This happened in spite of virus-induced accumulation of several other innate-immune cell populations in the dLN. UV inactivation of VACV or use of the Modified Vaccinia virus Ankara (MVA) strain promoted DC movement to dLN, indicating that the virus actively interferes with skin DC migration. This active immune suppression by VACV was potent enough to ablate the mobilization of skin DCs in response to BCG, and to reduce the transport of BCG to dLN. Expression of inflammatory mediators associated with BCG-triggered DC migration were absent from virus-injected skin, suggesting that other pathways provoke DC movement in response to replication-deficient VACV. Despite viral suppression of DC migration, VACV was detected in dLN much earlier than BCG, indicating a rapid, alternative route of viral traffic to dLN despite marked blockade of skin DC mobilization from the site of infection.

immunology

Operative and technical modifications to the Coriolis(R) μ air sampler that improve sample recovery and biosafety during microbiological air sampling

Detecting infectious aerosols is central for gauging and countering airborne threats. In this regard the Coriolis(R) {micro} cyclonic air sampler is a practical, commercial collector that can be used with various analysis methods to monitor pathogens in air. However, information on how to operate this unit under optimal sampling and biosafety conditions is limited. We investigated Coriolis performance in aerosol dispersal experiments with polystyrene microspheres and Bacillus globigii spores. We report inconsistent sample recovery from the collector cone due to loss of material when sampling continuously for more than 30 min. Introducing a new collector cone every 10 min improved this shortcoming. Moreover, we found that several surfaces on the device become contaminated during sampling. Adapting a HEPA-filter system to the Coriolis prevented contamination without altering collection efficiency or tactical deployment. A Coriolis modified with these operative and technical improvements was used to collect aerosols carrying microspheres released inside a Biosafety Level-3 laboratory during simulations of microbiological spills and aerosol dispersals. In summary, we provide operative and technical solutions to the Coriolis that optimize microbiological air sampling and improve biosafety.

microbiology