TABLE 2.

Serological and molecular analysis of five allogeneic SCT recipients with HHV-8-specific antibodies in plasma by peptide EIAs^d

Patient no. and transplantation day	IFAa		ABI-EIA		Peptide EIAs OD (serologic statusc)		Real-time PCR
	Latent	Lytic	OD	OD/cutoff (serologic statusb)	ORF K8.1	ORF 65	PMNL	Plasma
1
−7	1/50	1/50	0.070	0.330 (−)	0.110 (−)	0.097 (−)	NDe	ND
21	−	−	0.050	0.237 (−)	0.240 (+)	0.230 (+)
91	1/200	1/100	0.071	0.336 (−)	0.330 (+)	0.250 (+)
2
−7	1/50	1/50	0.056	0.265 (−)	0.692 (+)	0.372 (+)	ND	ND
21	1/100	1/100	0.052	0.246 (−)	1.000 (+)	0.360 (+)	ND
91	−	1/50	0.072	0.341 (−)	1.200 (+)	0.400 (+)
3
−7	−	−	0.092	0.436 (−)	0.077 (−)	0.076 (−)	ND	ND
21	1/50	1/100	0.056	0.265 (−)	0.230 (+)	0.288 (+)	ND
77	1/50	−	0.077	0.365 (−)	0.250 (+)	0.250 (+)	ND
4
−7	−	−	0.076	0.360 (−)	0.062 (−)	0.099 (−)	ND	ND
21	1/100	1/50	0.051	0.242 (−)	0.270 (+)	0.230 (+)
91	−	−	0.058	0.275 (−)	0.320 (+)	0.220 (+)
5
−7	−	−	0.051	0.242 (−)	0.070 (−)	0.058 (−)	ND	ND
21	1/100	1/100	0.053	0.251 (−)	0.450 (+)	0.230 (+)
91	1/50	1/50	0.058	0.275 (−)	0.440 (+)	0.310 (+)

^aIFA values for both latent and lytic antigens correspond to the highest dilution at which membrane staining was observed by fluorescence microscopy.

^bSerologic status was determined as described by the manufacturer's instructions (ABI) based on a cutoff value which is threefold higher than the mean of three negative samples. Absorbance/cutoff ratios were interpreted as follows: ≤0.75, negative sample; ≥1.00, positive sample; 0.76-0.99, equivocal (borderline).

^cSerologic status was determined by comparison with predetermined cutoff values, which were 0.194 and 0.220 for ORF K8.1 and ORF 65 EIAs, respectively. The mean absorbance of 20 healthy children's plasma samples plus 4 standard deviations was chosen as the cutoff value for the peptide EIAs.

^dNote: each sample was tested in duplicate by the three serological methods and by quantitative real-time PCR. −, negative result; +, positive result.

^eND, not done.