Table 1.

Characteristics of patients.

Group	N	Gender F/M	Age (years) mean ± SD	No. of natalizumab infusions mean ± SD	EDSS median (IQR)	No. of relapses in the past 6 months mean ± SEM
Cohort for B cell analysis
• Healthy volunteers	12	10/2	41.0 ± 4.09	NA	NA	NA
• Untreated RRMS	12	8/4	55.7 ± 3.13	NA	3.0 (2.5–3.8)	0.16 ± 0.11
• Nat 3–24 months	12	10/2	40.5 ± 3.64	14.0 ± 1.97	3.25 (1.6–3.8)	0.25 ± 0.17
• Nat >24 months	12	9/3	39.2 ± 2.32	66.7 ± 6.60	2.5 (2.0–3.5)	0
Cohort for CD4+T cell analysis
• Healthy volunteers	12	8/4	36.1 ± 2.78	NA	NA	NA
• Untreated RRMS	12	9/3	46.8 ± 2.81	NA	2.25 (1.5–3.8)	0.08 ± 0.08
• Nat 3–24 months	12	8/2	42.6 ± 3.93	12.8 ± 2.35	3.0 (2.0–4.3)	0.33 ± 0.14
• Nat >24 months	12	10/2	39.8 ± 2.23	39.6 ± 1.67	3.25 (3.0–3.8)	0
Cohort for CD8+T cell analysis
• Healthy volunteers	12	8/4	41.4 ± 2.93	NA	NA	NA
• Untreated RRMS	12	9/3	47.4 ± 2.98	NA	2.0 (1.5–3.2)	0.16 ± 0.11
• Nat 3–24 months	10	8/2	39.8 ± 3.73	8.7 ± 2.70	2.5 (1.3–4.0)	0.60 ± 0.26
• Nat >24 months	12	10/2	41.0 ± 2.80	51.1 ± 4.55	3.0 (2.1–4.5)	0.16 ± 0.16
Cohort for monocyte analysis
• Healthy volunteers	11	9/2	39.4 ± 4.12	NA	NA	NA
• Untreated RRMS	12	8/4	55.7 ± 3.13	NA	3.0 (2.5–3.8)	0.16 ± 0.11
• Nat 3–24 months	12	10/2	40.5 ± 3.64	14.0 ± 1.97	3.25 (1.6–3.8)	0.25 ± 0.17
• Nat >24 months	11	8/3	40.2 ± 2.29	69.0 ± 6.81	2.5 (2.0–3.5)	0
Cohort for PBMC analysis
• Healthy volunteers	14	8/6	46.0 ± 2.93	NA	NA	NA
• Untreated RRMS	20	14/6	52.1 ± 1.88	NA	2.0 (1.7–2.5)	0.05 ± 0.05
• Nat 3–24 months	21	16/5	40.0 ± 2.79	14.0 ± 1.74	3.5 (2.7–4.2)	0.35 ± 0.10
• Nat >24 months	22	17/5	40.6 ± 2.20	49.0 ± 3.62	3.25 (2.5–4.0)	0
• PML	15	12/3	45.9 ± 2.22	33.5 ± 3.34	–	–

IQR: interquartile range; EDSS: Expanded Disability Status Scale; RRMS: relapsing–remitting multiple sclerosis; Nat: natalizumab; PBMC: peripheral blood mononuclear cell; PML: progressive multifocal leukoencephalopathy.