Table III.

Expression of PD-L1 and PD-L2 by CD8a⁻ and CD8a⁺ DC, mDC and pDC in young and aged mice

Tissue	CD8α⁺ DC PD-L1			CD8α⁺ DC PD-L2
Tissue	Young	Aged	p^b	Young	Aged	p^b
Spleen	45.8 ± 5.6	62.9 ± 6.7	0.08	7.8 ± 2.1	18.7 ± 4.2	0.03
LN	41.3 ± 14.5	45.3 ± 17.6	0.87	9.7 ± 3.0	12.7 ± 5.5	0.62
Lungs	70.4 ± 5.7	58.0 ± 7.3	0.68	12.9 ± 3.7	16.2 ± 2.9	0.50
PP	24.5 ± 10.8	32.1 ± 13.4	0.67	7.3 ± 2.2	11.1 ± 7.5	0.74

Tissue	CD8α⁻ DC PD-L1			CD8α⁻DC PD-L2
Tissue	Young	Aged	p^b	Young	Aged	p^b
Spleen	42.7 ± 5.1	57.0 ± 7.1	0.14	5.6 ± 1.2	18.6 ± 4.8	0.05
LN	42.2 ± 6.6	44.8 ± 3.4	0.76	10.0 ± 3.1	11.9 ± 2.6	0.67
Lungs	53.3 ± 2.3	55.1 ± 3.2	0.23	6.6 ± 0.8	13.1 ± 1.1	<0.01
PP	33.4 ± 12.1	39.3 ± 15.1	0.77	9.7 ± 2.3	12.5 ± 7.8	0.64

Tissue	mDC PD-L1			mDC PD-L2
Tissue	Young	Aged	p^b	Young	Aged	p^b
Spleen	79.2 ± 2.1	79.2 ± 5.0	1.00	3.3 ± 0.7	24.1 ± 7.3	0.02
LN	90.5 ± 1.1	93.3 ± 2.1	0.25	31.9 ± 4.6	33.5 ± 4.0	0.81
Lungs	28.0 ± 4.4	60.5 ± 5.9	0.01	3.3 ± 0.4	10.8 ± 2.6	0.02
PP	80.9 ± 5.1	91.6 ± 2.8	0.10	10.7 ± 5.8	22.6 ± 8.1	0.27

Tissue	pDC PD-L1			pDC PD-L2
Tissue	Young	Aged	p^b	Young	Aged	p^b
Spleen	47.4 ± 8.1	78.1 ± 4.8	0.01	16.9 ± 6.0	29.3 ± 7.6	0.24
LN	24.8 ± 5.1	25.2 ± 12.9	0.97	3.1 ± 0.3	4.4 ± 2.3	0.54
Lungs	66.8 ± 3.5	75.7 ± 4.5	0.17	7.6 ± 2.6	13.2 ± 3.6	0.23
PP	11.1 ± 6.3	28.8 ± 15.2	0.32	8.9 ± 1.2	10.9 ± 7.8	0.83

Cells were obtained from aged mice (≤2-month-old; N≥ 3) and young mice (≤16-month-old; N≥ 3). CD8α⁻ DC were defined as CD11c⁺CD8α⁻, CD8α⁺ DC as CD11c⁺CD8α⁺. mDC are defined as CD11c⁺CD11b⁺Gr1⁻CD317⁻ and pDC as CD11c⁺CD11b⁻Gr1⁺CD317⁺. Values represent the mean (±SEM) percentage of each subset in the live population defined by 7-AAD exclusion.

p values (t-test) compare the percentage of each subset in young and aged mice.