Host Response to Infection by Direct Analysis of Leukocyte Single Cell-type Gene Expression/transcript Abundance, Direct LS-TA

Febrile illness is a common condition, particularly among young patients and it is crucial to have an early triage of patients according to various aetiologies to enable appropriate treatment. Most diagnostic tests are targeted towards the detection of pathogens while other assays are mostly related to serum proteins. Blood cells transcriptome has been explored to differentiate bacterial and viral infections. Here, we propose to develop a rapid test using the host responses in terms of gene expressions of single-cell populations of peripheral leukocytes (monocytes and granulocytes) to differentiate three major categories of infections that are bacterial, viral, and tuberculosis. The assay is called Direct leukocyte single cell-type transcript abundance (TA) assay (DIRECT LS-TA) as it can directly determine the gene expression of a specified single cell-type (e.g. monocytes and granulocytes) among various leukocyte cell populations directly in a peripheral blood sample. Such results signify the nature of host response and can be used to indicate the type of infection (viral, bacterial or active tuberculosis).