TLR4 and myeloid sarcoma: Given that GABAB activation modulates TLR4-induced signaling in primary mixed glia (Figure 2), and that TLR4 stimulation enhances TNF-α signaling in PBMCs from control and RR-MS patients (Figure 4), we next assessed the proclivity of baclofen to modulate TLR4-induced TNF-α release in PBMCs isolated from healthy subjects and RR-MS patients.