TABLE 1.

Analysis of clinical parameters and P-gp expression in total PBMC, CD4⁺ T lymphocytes, and CD14⁺ monocytes from HIV⁺ patients^a

No. of group	Patient code	Therapy	Viremia (copies/ml)	No. of CD4 cells/mm³	Treatment protocol	P-gp expression
No. of group	Patient code	Therapy	Viremia (copies/ml)	No. of CD4 cells/mm³	Treatment protocol	PBMC	CD4⁺	CD14⁺
1	CM0612	Naive	2,900	322		1.05	1.23	2.00
	GR1411	Naive	2,400	629		1.10	1.21	6.21
	AS1512	Naive	2,300	433		0.99	1.06	1.75
	VC1512	Naive	190,000	267		1.01	1.22	1.74
	BG2211	Naive	25,000	630		1.03	1.00	1.65
2	DF0612	Responder	<80	657	2 NRTI + 1 NNRTI	0.99	0.96	1.45
	D10612	Responder	<80	719	2 NRTI + PI	1.05	1.13	1.22
	MC0612	Responder	<80	808	2 NRTI + PI	1.08	1.00	1.95
	ER1411	Responder	<80	356	2 NRTI + 1 NNRTI	0.88	0.88	3.55
	AG1512	Responder	<80	420	2 NRTI + PI	1.03	1.27	1.34
	GW1512	Responder	<80	867	2 NRTI + PI	1.00	0.99	1.15
	BA2211	Responder	<80	805	2 NRTI + 1 NNRTI	1.03	0.96	2.74
	OA2211	Responder	<80	309	2 NRTI + PI	0.97	0.96	2.74
3	AG0612	Nonresponder	12,000	363	2 NRTI + PI	1.07	1.07	2.02
	FL1512	Nonresponder	84,000	20	2 NRTI + PI	0.53	0.57	1.38
	PE1512	Nonresponder	13,000	373	2 NRTI + PI	1.01	0.98	1.55
	DT2211	Nonresponder	46,000	299	2 NRTI + PI	0.98	1.17	3.31
	CF0612	Nonresponder	98,000	64	2 NRTI + 1 NNRTI	1.00	1.11	1.49

↵ a Cytometric analysis of surface antigen expression was performed as previously described (12) by using the following monoclonal antibodies: anti-CD14-phycoerythrin (clone M5E2; Becton Dickinson, Mountain View, Calif.), anti-CD4-phycoerythrin-Cy5 (clone RPA-T4; Becton Dickinson), and anti-P-gp-fluorescein isothiocyanate (clone 12.10), which was kindly provided by Dr. M. Cianfriglia (Rome, Italy). Briefly, 5 × 10⁵ PBMC were washed in 1% phosphato-buffered saline, 1% bovine serum albumin, and 0.1% sodium azide and were incubated for 15 min at 4°C with monoclonal antibodies. Samples were fixed in 1% paraformaldehyde, immediately acquired by a FACScalibur flow cytometer (Becton Dickinson), and analyzed with CellQuest software (Becton Dickinson). P-gp expression was analyzed in different cellular subsets: total PBMC, CD4⁺ T lymphocytes, and CD14⁺ monocytes. Data are indicated as an intensity index, which is obtained by dividing the median fluorescence intensity seen with the P-gp-specific monoclonal antibody by that seen with the immunoglobulin G2a isotype control (p170/immunoglobulin G), as previously described (10). NRTI, nucleoside reverse transcriptase inhibitors; NNRTI, nonnucleoside reverse transcriptase inhibitor.