Platelet-endothelial associations may promote cytomegalovirus replication in the salivary gland in mice.

Platelet decline is a feature of many acute viral infections, including cytomegalovirus (CMV) infection in humans and mice. Platelet sequestration in association with other cells, including endothelium and circulating leukocytes, can contribute to this decline and influence the immune response to and pathogenesis of viral infection. We sought to determine if platelet-endothelial associations (PEAs) contribute to platelet decline during acute murine CMV (mCMV) infection, and if these associations affect viral load and production. Male BALB/c mice were infected with mCMV (Smith strain), euthanized at timepoints throughout acute infection and compared to uninfected controls. An increase in PEA formation was confirmed in the salivary gland at all post-inoculation timepoints using immunohistochemistry for CD41+ platelets co-localizing with CD34+ vessels. Platelet depletion did not change amount of viral DNA or timecourse of infection, as measured by qPCR. However, platelet depletion reduced viral titer of mCMV in the salivary glands while undepleted controls demonstrated robust replication in the tissue by plaque assay. Thus, platelet associations with endothelium may enhance the ability of mCMV to replicate within the salivary gland. Further work is needed to determine the mechanisms behind this effect and if pharmacologic inhibition of PEAs may reduce CMV production in acutely infected patients.

Rapid liquid chromatography tandem mass spectrometry method for targeted quantitation of human performance metabolites in saliva.

Saliva is increasingly being targeted for metabolic studies due to its non-invasive collection methods. Tracing levels of certain metabolites within biofluids can provide indications for a myriad of physiological conditions. This study was performed on a panel of eight analytes found in saliva that have shown associations with physiological conditions of human performance, such as stress, inflammation, and circadian rhythm. This dual polarity liquid chromatography tandem mass spectrometric (LCMS/MS) method was developed to accommodate a diverse group of analytes including steroids, alkaloids, and neurotransmitters. Samples collected during field exercises from soldiers were compared to those of civilians and baseline levels of each of these compounds was determined in saliva. Although most analytes showed no significant differences between the two populations, relative cortisol levels were higher for soldiers than for civilians. This developed dual polarity LCMS/MS method can be applied to very diverse groups of salivary analytes simultaneously.