Table 3

Correlations between IFN scores and serum KYN/TRP pathway metabolite levels in subjects with SLE according to ISG and monocyte-associated gene expression subgroups

ISG expression subgroupMonocyte-associated gene expression subgroupIFN score method (z-scores)KYN/TRP (rs)P valueQA/KA (rs)P value
IFN high (n=36)Monocyte high (n=23)ISG-A0.5040.014*0.4290.041*
19 type I ISG0.5320.009*0.4190.046*
Monocyte low (n=13)ISG-A0.4400.133−0.1320.668
19 type I ISG0.3300.2710.0440.887
IFN low (n=23)Monocyte high (n=17)ISG-A−0.2890.260−0.3260.202
19 type I ISG0.3360.188−0.2520.328
Monocyte low (n=6)ISG-A0.5470.2610.1370.796
19 type I ISG0.4290.3960.0730.890
IFN similar to HC (n=13)Monocyte high (n=8)ISG-A−0.0710.867−0.1990.637
19 type I ISG0.0480.911−0.0240.955
Monocyte low (n=5)ISG-A0.7850.1160.1100.861
19 type I ISG0.5000.3910.1000.873
  • In addition to the ISG expression subgroups previously described in table 2, subjects with SLE were further designated as either ‘monocyte high’ (monocyte-associated gene expression >HC mean) or ‘monocyte low’ (monocyte-associated gene expression ≤HC mean). In each subgroup, correlations between both IFN scores (derived from ISG-A and the 19 type I ISG) and metabolite ratios are displayed.

  • *Remained significant after Benjamini-Hochberg correction for multiple comparisons.

  • HC, healthy control; IFN, interferon; ISG, interferon-stimulated gene; KYN, kynurenine; QA, quinolinic acid; TRP, tryptophan.