Table 2.

Studies showing that RNA co-isolated with virion preparations were classified based on the purification methods used. * When indicated, the corresponding experiments were performed intending to rule out EV contamination. HSV-1: herpes simplex viruses 1, HCMV: human cytomegalovirus, MHV-68: murine gammaherpesvirus 68, KSHV: Kaposi’s sarcoma herpesvirus, HBV: hepatitis B virus, EBV: Epstein-Barr virus, WB: Western blot.

Purification Method	Gradient or Size Limit	Reference	Virion/EV Separation *	Virus	Detected RNA
Dextran gradient centrifugation	1.04–1.09 g/cm3	[4,5]	-	HSV-1	mRNA
Sucrose gradient centrifugation	35%, 30%–60%	[6]	-	HCMV	vRNA
	20%–40%	[7]	Detergent treatment, Infectivity	HCMV	mRNA
	20%, 10%–55%	[8]	-	MHV-68	vtRNA
	30%–60%	[9]	Banding, WB	KSHV	miRNA, usRNA
Histodenz gradient centrifugation	20%–35%	[10]	-	KSHV	mRNA
CsCl gradient centrifugation	n.a.	[12]	-	Adenovirus	mRNA
		[13]	-	Adenovirus	mRNA
Sorbitol cushion centrifugation	20%	[11]	-	HBV	miRNA
Sorbitol cushion, Glycerol-tartrate gradient, CsCl gradient centrifugation	n.a.	[14]	Banding	HCMV	mRNA
Filtration	0.8 µm	[15]	-	EBV	mRNA, non-coding RNA