Characterization of Enteroviruses Isolated from Patients with Aseptic Meningitis

Enteroviruses (EVs) are human pathogens that cause a wide variety of clinical illnesses. The spectrum of the diseases ranges from a mild febrile illness to severe diseases such as meningitis or myocarditis. In the present study, we have used a reverse transcription-polymerase chain reaction method to detect EVs from patients with aseptic meningitis followed by typing of the EVs after HeLa cell culture isolation. In addition, twelve reference strains and the six clinical isolates of EVs were infected to neonatal rat cardiocytes and the viability of infected cells was measured by MTT assay. Marked inhibition of cell proliferation was observed in the cardiocytes cultures infected with coxsackievirus (CV) B1, CVB4, and CVB5, and two wild strains, whereas mild inhibition was observed from those infected with CVB2, CVB3, echoviruses 6, 7, 11, 22, 25, and 30. Recombinant plasmid containing full-length cDNA genome of the cardiovirulent wild strain was successfully constructed and its complete nucleotide sequence was determined. The genome showed characteristics of enteroviruses. The RNA genome was 7,391 nucleotides in length, with a 5'-nontranslating region (742 nucleotides) followed by an open reading frame (encoding a 2,182 amino acid polyprotein) and a 3'-nontranslating region (100 nucleotides) and polyadenylated tail. The predicted amino acid sequences of the polyprotein showed 89~95% homology with those of reference coxsackievirus strains (CVB1-5).

Detection and Characterization of Enteroviral RNA in Paraffin-embedded Heart Tissues form Patients with Dilated Cardiomyopathy

The aim of this study was to investigate viral etiology in dilated cardiomyopathy (DCM) by polymerase chain reaction (PCR) or nested reverse tanscription PCR (RT-PCR), and characterize the enteroviral RNA presented in the clinical specimens. Twenty-eight paraffin-embedded heart tissue samples were assayed to detect cytomegalovirus, herpes simplex virus type 1, type 2, parvovirus, adenovirus, and enterovirus (EV) with each specific primer. Of these 28 patients (mean age: 27, M: 24, F: 4), 26 were histologically diagnosed as DCM and 2 as myocardial infarction (MI). Nested RT-PCR detected enteroviral RNA in 7 (26.9%) of 26 patients with DCM, and none of patients with MI. And none of DNA viruses tested were detected from the samples. Amplified products were also genotyped by single-variation of EV is present in the explanted heart tissues from patients with DCM. Although most of the sequences among the wild isolates have the greatest similarity to those of coxsackievirus B3, there are specific regions of variable sequences (no 490 - no 510). The data suggest that enterovirus may be a major viral pathogen for the DCM in Korea and nucleotide sequence data indicate that coxsackievirus B3 may be a leading etiologic agent of DCM.