Commentary: Methamphetamine mediates immune dysregulation in a murine model of chronic viral infection

Citation: Loftis JM (2015) Commentary: Methamphetamine mediates immune dysregulation in a murine model of chronic viral infection. A commentary on Methamphetamine mediates immune dysregulation in a murine model of chronic viral infection The recent article by Sriram et al. (2015) is one of the first studies to evaluate the effects of methamphetamine on peripheral T cell responses, in the context of a chronic viral infection. Using lymphocytic choriomeningitis virus (LCMV) clone 13 as a model of chronic viral infection in mice, investigators found that exposure to methamphetamine significantly alters the expression of peripheral T cell factors putatively involved in infection control. In particular, the expression of programmed cell death protein-1 (PD-1), type 3 inflammatory CXC chemokine receptor (CXCR3), and epidermal growth factor receptor (EGFR) was increased on T cell subsets from LCMV-infected mice exposed to methamphetamine. Collectively, these immune cell changes have the potential to adversely impact key anti-viral immune functions, such as T cell recruitment, cytokine production, and exhaustion. Given the high prevalence of chronic viral infections [e.g., human immunodeficiency virus (HIV) and hepatitis C virus (HCV)] associated with methamphetamine and other substance use disorders, including alcohol (Martínez-Raga et al., 2001), it is important to determine how substances of abuse effect T cell responses involved in the etiology and progression of chronic viral infection. Co-morbid substance use disorders and HIV and/or HCV infections are also often associated with impairments in central nervous system (CNS) function (Carey et al. and depression), potentially caused by substance abuse-related peripheral immunosuppression, could lead to further likelihood of relapse or increased substance use. Indeed, the tendency of adults with substance use disorders to self-medicate with alcohol and other drugs of abuse (Bolton et al., 2009; Crum et al., 2013) could be recognized as a possible complication of untreated or uncontrolled viral infection symptoms. These and other findings highlight the converging effects of substances of abuse on immune function—effects that contribute to the addiction and increase susceptibility for the progression of chronic viral infections. Despite changes in peripheral T cell markers associated with viral clearance, Sriram et al. (2015) reported that methamphetamine