Introduction: The significance of HHV-8 DNA detection in bone marrow stromal cells from patients with multiple myeloma is still controversial. Since IL-6 plays a key role in the pathogenesis of myeloma, we studied the effect of this lymphokine on HHV-8 DNA detection.
Materials and methods: Amplification of HHV-8 DNA from long-term bone marrow cultures established from normal individuals in the presence or absence of 1 ng/ml IL-6 and from an HHV-8 infected ISI cell line.
Results and conclusions: IL-6 increased HHV-8 replication in seven of ten bone marrow cultures as well as in the ISI cell line. Quantitative PCR showed a 3-100-fold increase in HHV-8 DNA copy number/microg DNA. These data suggest that when IL-6 is present in the micro-environment, HHV-8 replicates and may be amplified in the absence of systemic infection in patients without cellular immune deficiency.