SLC/CCL21-mediated anti-tumor responses require IFNγ, MIG/CXCL9 and IP-10/CXCL10

Table 1 Neutralization of IP-10, MIG and IFNγ reduces the frequency of CD3⁺CXCR3⁺ T lymphocytes and CD11C⁺ DEC205⁺ DC at the tumor site of SLC/CCL21-treated mice

	+ Anti IP-10		+ Anti MIG		+ Anti IFNγ		+ anti Control Ab		Diluent Control
	%	MCF	%	MCF	%	MCF	%	MCF	%	MCF
CD4	13	44	14	47	13	40	*13	42	*6	48
CD8	35	57	34	55	32	50	*33	52	*26	52
CD3CXCR3	**28	58	**27	57	**23	55	* 34	59	*12	58
CD11C ⁺ DEC 205 ⁺	**10	111	**9	110	**11	101	*14	105	*4	100

Single cell suspensions of non-necrotic tumor nodules from SLC/CCL21 treated mice receiving neutralizing antibodies to P-10/CXCL10, MIG/CXCL9, IFNγ, control Ab and diluent treated tumor bearing mice were prepared. Cell surface staining for T cell markers CD4, CD8, CD3, and the chemokine receptor CXCR3 as well as DC markers CD11C and DEC205 were evaluated by flow cytometry. Cells were identified as lymphocytes or DC by gating on the forward and side scatter profiles; 10,000 gated events were collected and analyzed using Cell Quest software. Within the gated T lymphocyte population, intratumoral injection of SLC/CCL21 led to an increase in the frequency of CD4⁺, CD8⁺, CD3⁺CXCR3⁺ events compared to the diluent control (*p < 0.001). Within the gated DC population, intratumoral injection of SLC/CCL21 led to an increase in the frequency of CD11C⁺DEC205⁺ events compared to the diluent control (*p < 0.001). Compared to SLC/CCL21-treated mice receiving control antibody, mice receiving neutralizing antibodies to IP-10/CXCL10, MIG/CXCL9, and IFNγ showed decrease in the gated CD3⁺CXCR3⁺ T cell as well as CD11C⁺DEC205 ⁺ DC events (**p < 0.01) (n = 8 mice per group). MCF is mean channel fluorescence intensity. CD3⁺CXCR3⁺ MCF is for CXCR3. CD11C⁺DEC205⁺, MCF is for DEC205.

ISSN: 1476-4598