Differences between naive and memory T cell phenotype in Malawian and UK adolescents: a role for Cytomegalovirus?

BMC Infectious Diseases

Table 2 Median percentages of naïve and memory T cells based on CCR7 expression in Malawian and UK adolescents (12–15 year olds) and young adults (16–25 year olds) stratified by age.

		UK adolescents (n = 30)		Malawi adolescents whole group (n = 26)		Malawi adolescents (12-15 year olds) (n = 5)		Malawi young adults (16-25 year olds) (n = 21)
		CD4⁺	CD8⁺	CD4⁺	CD8⁺	CD4⁺	CD8⁺	CD4⁺	CD8⁺
%CCR7 naïve (i.e. CD45RA⁺CCR7⁺)^a	median	43	55	25	19	27	16	23	21
	range	1–79	15–87	0.4–59	1–72	24–38	9–41	0.4–59	1–72
	p			0.002	<0.001	0.09	0.001	0.003	0.001
%CCR7 memory that are central memory (i.e. CD45RA^-CCR7⁺)^b	median	47	24	14	4	9	1	14	5
	range	2–90	0–73	1–84	0.1–54	3–42	0.5–6	1–84	0.1–54
	p			0.004	0.001	0.007	0.003	0.02	0.01
%CCR7 memory that are effector memory (i.e. CD45RA^-CCR7^-)^c	median	29	29	41	31	36	27	42	32
	range	4–50	0–56	15–76	12–56	15–41	14–34	15–76	12–56
	p			0.02	0.81	0.48	0.48	0.01	0.57
%CCR7 memory that are stable memory (i.e. CD45RA⁺CCR7^-)^d	median	18	42	35	60	52	73	27	52
	range	0.2–95	9–100	0.3–82	16–87	17–82	61–83	0.3–59	16–87
	p			0.16	0.03	0.02	0.02	0.50	0.12

P values versus UK adolescents, based on Wilcoxon rank-sum test. Ranges are minimum and maximum values.
^a Percentage of all CCR7 cells that are naïve.
^{b, c, d} Of the CCR7 cells that are memory, proportion that are either central memory (b), effector memory (c) or stable memory (d) (percentages in b, c, and d sum to 100).

ISSN: 1471-2334