Levels of chemokine mRNA expression in EBV-positive (▪) and EBV-negative (□) HD tissues. Total cellular RNA, extracted from paraffin-embedded tissues diagnosed with MC, NS, or NLP HD was subjected to semiquantitative RT-PCR. After normalization to a standard RNA preparation and to G3PDH, the results of phosphorimage analysis are shown and plotted logarithmically as the geometric means (x/÷ SEM) of normalized arbitrary units (pixels)/group for each respective chemokine. SEMs were too small to be distinguished from the mean.