Table I.

Cell subsets important in mediating the effects of LPS on the establishment if hematopoietic chimerism in mice treated with costimulation blockade^a

Group	Host	LPS	Anti-NK	Anti-CD8	Anti-CD4	Chimerism Frequency	Donor-Origin PBMCs at 8 wk (%)	MST of Skin Grafts in Transplanted Mice (days)	MST of Skin Grafts in Nonchimeric Mice (days)	MST of Skin Grafts in Chimeric Mice (days)
1	C57BL/6	No	No	No	No	29/45 (64%)	1.59 ± 1.81	144	88	>260
2	C57BL/6	Yes	No	No	No	0/23 (0%)b	<0.10	11*	11	N/A
3	C57BL/6	No	Yes	No	No	11/13 (84.6%)	2.45 ± 1.16	>221	72	>221
4	C57BL/6	Yes	Yes	No	No	0/5 (<0.10%)c	<0.10	12**	12	N/A
5	C57BL/6	No	No	Yes	No	15/17 (88.2%)	0.90 ± 1.13	144	72.5	148
6	C57BL/6	Yes	No	Yes	No	0/16 (<0.10%)d	<0.10	44#	44	N/A
7	C57BL/6	No	Yes	Yes	No	7/8 (87.5%)	3.67 ± 1.23	81	23	81
8	C57BL/6	Yes	Yes	Yes	No	0/9 (<0.10%)e	<0.10	28##	28	N/A
9	C57BL/6	No	No	No	Yes	1/12 (8.33%)	0.58	46	37	>147
10	C57BL/6	Yes	No	No	Yes	0/12 (<0.10%)f	<0.10	18	18	N/A
11	C57BL/6	No	No	Yes	Yes	4/4 (100%)	2.42 ± 0.55	>228	N/A	>228
12	C57BL/6	Yes	No	Yes	Yes	4/4 (100%)g	1.14 ± 0.35	228	N/A	228
13	CD8α−/−	No	No	No	No	12/17 (70.5%)	2.29 ± 1.76	96	51	136
14	CD8α−/−	Yes	No	No	No	0/17 (<0.10%)h	<0.10	21$	21	N/A

^aAll mice were treated with a BALB/c DST and anti-CD154 mAb and transplanted with BALB/c bone marrow and skin according to our standard protocol without or with injection of 100 µg of LPS. Groups 3, 4, 7, and 8 were also given an injection of anti-NK1.1 mAb i.p on day −10 relative to bone marrow and skin transplantation. Groups 5, 6, 7, 8, 11, and 12 were given three doses of 0.5 mg of anti-CD8 mAb i.p. on days −10, −9, and −8 relative to bone marrow and skin transplantation. Groups 9, 10, 11, and 12 were given three doses of 0.5 mg of anti-CD4 mAb i.p. on days −10, −9, and −8 relative to bone marrow and skin transplantation. Hematopoietic chimerism was defined as >0.10% donor origin PBMCs 8 wk after bone marrow injection. The percentage of donor origin PBMCs is the mean ± SD percentage of the levels observed in chimeric mice. For groups with no chimeric mice, we used the limit of detection (<0.10) to indicate a lack of chimerism.

^bp = 0.017 vs group 1

^cp = 0.0005 vs group 3

^dp < 0.0001 vs group 5

^ep = 0.0003 vs group 7

^fp = NS vs group 9

^gp = NS vs group 11

^hp < 0.0001 vs group 13 by χ² analysis.

^*p < 0.001 vs group 1

^**p < 0.0001 vs group 3

^#p < 0.0001 vs group 5

^##p < 0.01 vs group 7

^$p < 0.001 vs group 13 by log-rank analysis.

N/A, Not applicable.