Methotrexate Treatment Suppresses Monocytes in Nonresponders to Pneumococcal Conjugate Vaccine in Rheumatoid Arthritis Patients

Table 4

Frequencies of circulating leukocytes in RA patients with MTX treatment, before vaccination with PCV13, sorted in responders and nonresponders.

Phenotype (% of leukocytes unless otherwise specified)	MTX pre-PCV13 Responders ()	MTX pre-PCV13 Nonresponders ()	value
Monocytes	11.2 (7.02-12.5)	4.24 (2.23-5.69)	0.02
CD14^++CD16^- (% of monocytes)	86.9 (83.2-92.0)	68.2 (43.6-90.4)	ns
CD14^++CD16^+ (% of monocytes)	3.35 (1.69-6.08)	6.69 (1.10-15.9)	ns
CD14^+CD16^++ (% of monocytes)	9.68 (6.36-10.8)	25.1 (6.52-42.5)	ns
Granulocytes	62.2 (58.0-65.0)	70.4 (51.9-77.6)	ns
Basophils	1.19 (1.04-1.51)	1.36 (1.10-1.37)	ns
Eosinophils	2.70 (2.58-3.87)	5.92 (5.03-8.64)	0.02
Neutrophils	58.3 (54.1-59.8)	63.8 (45.0-67.6)	ns
Lymphocytes	24.0 (18.9-27.5)	22.4 (14.0-39.1)	ns

Frequencies of circulating monocytes, granulocytes, and lymphocytes analyzed in RA patients on MTX, immediately before administration of PCV13, using flow cytometry. Positive antibody response was defined as an antibody response ratio (ARR, i.e., the ratio of post- to prevaccination antibody levels) ≥ 2, in > 50% of serotypes. Mann–Whitney test was used to calculate level of significance. Data are presented with medians and interquartile ranges. RA: rheumatoid arthritis; MTX: methotrexate; PCV13: 13-valent pneumococcal conjugate vaccine; ns: not significant. Antibody titers were available in 9 of 11 patients on MTX.