TABLE 3.

Determinants for homosexual HIV-1 transmission

Couplea	Infectious cellular load (TCID/ 106 CD4+ T cells)	RNA load (log copies/ml of serum)	Mean CD4+ cell counts/μl	Relative susceptibility	CCR5 genotypec for:
					NR or R	NT or T
D1	4	3.40	520	++	wt	hz
D2	3	4.52	523	++	wt	wt
D3	3	3.93	443	+	wt	wt
D4	44	4.80	863	+	wt	wt
D5	4	4.38	330	+	wt	hzd
D6	21	4.94	807	+/−	wt	wt
D7	12	4.72	660	+/−	hz	wt
D8	66	4.72	613	−	hz	wt
D9	18	4.20	457	−	wt	wt
D10	4	3.79	630	−	hz	wt
C1	10	3.00	390	+++	wt	wt
C2	115	4.64	560	+++	wt	wt
C3	11	3.77	363	++	wt	wt
C4	16	3.18	367	++	wt	hzd
C5	122	4.46	480	++	wt	wtd
C6	382	4.81	360	+	wt	wt
C7	1,868	5.32	120	+	wt	hzd
C8	213	4.67	467	+/−	wt	wt
C9	79	5.23	503	NTb	wt	hze
C10	395	5.60	520	NT	wt	wt

^aD, discordant; C, concordant. 

^bNT, not tested. 

^cwt, wild type; hz, heterozygous. 

^dIndividuals from whom viruses were isolated that replicated to normal titers on PBMC with reduced susceptibilities from blood donors bd1 and bd3. 

^eViruses were not tested for replication on PBMC of different origins.