Previously, it has been demonstrated that neurotropic strains of MHV can directly infect different neural cell types [16, 19, 38, 39] but there is no evidence whether neurotropic strain can directly infect microglia or only acquire activity indirectly due to the infection of other neural cell types.
At 12 hrs postinfection, infected microglia demonstrated stressed morphology and started to fuse with the neighbouring cells, and at 24 hrs postinfection, most of the infected cells were involved into large syncytia formation (Figure 4(c)) which is a characteristic of some enveloped RNA viruses and more specifically characteristic of MHV-A59 (parental strain of RSA59), an enveloped demyelinating strain of MHV .
To understand the cellular mechanism of demyelination of neurotropic strain of MHV, prior studies in our laboratory have analyzed the detailed pathogenesis of recombinant MHV strain, RSA59 (demyelinating strain (DM)) and compared it with RSMHV2 (nondemyelinating strain (NDM)) that is isogenic except for the spike gene that encodes the virus-host-attachment spike glycoprotein [18, 20].
Affymetrix microarray analyses for mRNA expression have revealed that expression of inflammatory mediators by MHV infected microglia, including chemokine and inflammatory cytokines.
Our current microglial tropism studies revealed that RSA59, an isogenic demyelinating strain of MHV, can infect and activate CNS resident microglia, and microglia can help to mediate demyelination by engulfing myelin debris.
Lyon, "Ependymitis, leukoencephalitis, hydrocephalus, and thrombotic vasculitis following chronic infection by mouse hepatitis virus 3 (MHV 3)," Acta Neuropathologica, vol.
Northern Michigan and MHVS addressed both issues through governance design.
Northern Michigan addressed its service concerns by contracting with a cardiologist from outside the area to work with the MHVS physicians on a peer-to-peer basis.
During the MHVS negotiations, one member of the group emerged as a strong advocate for employment.
As part of the acquisition process, MHVS engaged an industrial psychologist to work on internal dynamics.
To maintain group business operations, Northern Michigan retained more than 95 percent of MHVS's office staff.
The agreement finalized between Northern Michigan and MHVS includes a three-year non-compete clause.