In vitro detection of herpes simplex virus -1 and -2 infection with immunospecific Gd super(3+)-Cl sub(6)-enhanced magnetic resonance imaging

Herpes simplex virus infections are prevalent viral infections in humans. HSVs are also the most common cause of sporadic viral encephalitis (HSE). Magnetic resonance is the imaging method of choice for HSE because it provides the most sensitive method for detecting early lesions. The objective of this study is to set-up and in vitro test an experimental contrast agent specific for antigens present on HSV-infected cells, bound with a paramagnetic agent detectable by MR imaging. A selected anti-HSV HrFab was labelled with Alexa Fluor 488, super(125)I and Gd super(3+)Cl sub(6). In order to assess anti-HSV affinity and specificity, ELISA assays were performed. Vero cells infected with HSV strains were visualized by MRI using anti-HSV HrFab/Gd super(3+)Cl sub(6) complex. Results of the ELISA tests demonstrated that the anti-HSV HrFab labelled with Gd super(3+)Cl sub(6) showed similar affinity for the antigens while the super(125)I immunoconjugate showed reduced affinity. MRI confirmed high affinity and specificity of antibody for the detection of HSV infections.