7 ± 0.1 versus 3.5 ± 1.2 ng/mL);

again, the difference between PBC and controls was not significant (Fig. 1B). Thus the presence of TNF-α is critical for CX3CL1 production by BECs. The possibility that lymphocytes produced CX3CL122 was excluded by irradiation of LMCs, which did not significantly alter the results (data not shown). Also, LMCs without BECs never produced CX3CL1 with any TLR ligands, even after addition of IFN-γ or TNF-α. In the case of nondiseased controls, we were unable to study CX3CL1 production from BECs with LMCs and TNF-α, because sufficient LMCs were not available. BECs did not produce CX3CL1 on coculture with poly(I:C)-pretreated LMCs in GSK-3 inhibitor the presence of TNF-α, illustrated by representative data for one PBC liver (Fig. 2A), and indicating that BECs but not LMCs require poly(I:C) stimulation for production of CX3CL1. Such production decreased markedly when the BEC and LMC populations were separated by a filter in a transwell system (Fig. 2B). We assessed the functional effects of CD40, HLA class I, and HLA class II molecules on BECs by testing the capacity of blocking antibodies to CD154 and HLA molecules to suppress production

of CX3CL1 by BECs. Production of CX3CL1 by BECs was significantly decreased when CD40 on BECs was blocked from interacting with CD154 on LMCs (Fig. 2C). Having shown that LMCs and TNF-α are critically required for production of CX3CL1 by BECs, we next examined in detail the role of LMCs and TNF-α production. LMCs in the presence of poly(I:C) and TNF-α adhered to ECs and BECs and, notably, the number of such adherent LMCs from PBC livers exceeded that for PR-171 clinical trial control cases (394 ± 94 versus 116 ± 45 cells [P < 0.01] for ECs; 180 ± 63 versus 65 ± 40 cells [P < 0.01] for BECs). However, only very few LMCs adhered to LSECs, whether from PBC livers (21 ± 14) or controls (20 ± 15) (P > 0.05) (Fig. 3). The necessity of TNF-α for production by BECs of CX3CL1 medchemexpress led us to assess the source of available liver

TNF-α. As shown in Fig. 4, LMCs produced TNF-α following stimulation with most TLR ligands, and values for PBC exceeded those for disease controls. The data were as follows: LTA, 751 ± 163 versus 547 ± 138 pg/mL (P < 0.05); LPS, 1,699 ± 253 versus 1,303 ± 244 pg/mL (P < 0.01); and CL-097, 956 ± 188 versus 726 ± 154 pg/mL (P < 0.05) (Fig. 4). In the case of early noncirrhotic PBC, only a limited quantity of LMCs was available so that TNF-α production was measured only with or without LPS stimulation; here, TNF levels were 1,825 ± 334 pg/mL, which did not differ significantly from cirrhotic PBC (P > 0.05). There were, however, differences between noncirrhotic PBC and cirrhotic disease controls (P < 0.05) (Fig. 4). We then determined which subpopulations of LPS-stimulated LMCs produced TNF-α and, as shown in Fig. 5, the data for PBC livers versus disease control livers were as follows: monocytes, 476 ± 131 versus 336 ± 65 pg/mL (P < 0.05); NK cells, 179 ± 51 versus 107 ± 36 pg/mL (P < 0.