Anti-ICOS monoclonal antibody, clone JTB-4

Background: Members of B7 family are reported to regulate lymphocytes activation, transmit both costimulatory and co-inhibitory signals, control T cell-mediated immune responses and tolerance. Among which B7-H4 is reported to regulate the immune response negatively. Objective: To investigate the plasma concentration of soluble B7-H4 (sB7-H4) and its clinical significance in systemic lupus erythematosus (SLE). Methods: Fifty-six SLE patients with or without active SLE (ASLE) and 29 age- and gender-matched healthy volunteers were recruited. Plasma concentration of sB7-H4 was measured using sandwich ELISA kits. Results: Compared with healthy subjects, the concentration of sB7-H4 was significantly higher in patients with SLE (p=0.006). Plasma sB7-H4 concentration in patients with lupus nephritis (LN) were also significantly higher than healthy subjects (p=0.008), but no difference was found between LN and SLE patients without LN (non-LN). Additionally, the sB7-H4 concentration in patients was negatively correlated with the SLE disease activity index score (SLEDAI) (r=-0.3055, p=0.022). Compared with inactive disease, the concentration of sB7-H4 in ASLE patients was significantly lower (p=0.002). There were statistical significances between the positive and negative groups with decreased leukocytes or thrombocytes (p=0.012; p=0.033; respectively), but no statistically significant difference was found in other positive and negative serum laboratory indicators. Conclusions: The increased level of sB7-H4 in patients suggests that this pathway might be involved in the pathogenesis of SLE. However, the exact mechanism or physiological role of sB7-H4 in SLE pathogenesis remains to be investigated.

With the explosion of immuno-oncology and the approval of many immune checkpoint therapies by regulatory agencies in the last few years, understanding the tumor microenvironment (TME) in the context of patients' immune status has become essential. Among available immune profiling techniques, multiplex immunofluorescence (mIF) assays offer the unique advantage of preserving the architectural features of the tumor and revealing the spatial relationships between tumor cells and immune cells. A number of mIF and image analysis assays have been described for solid tumors but most are not sufficiently suitable in lymphoma, where the lack of clear tumor-stromal boundaries and high tumor density present significant challenges. Here we describe the development and optimization of a reliable workflow using Akoya Opal staining kits to label and analyze 6 markers per slide in diffuse large B-cell lymphoma (DLBCL) tissue sections. Five panels totaling 30 markers were developed to characterize infiltrating immune cells and relevant check-point proteins such as PD1, PD-L1, ICOS, SIRP-alpha and Lag3 on 70 DLBCL sections. Multiplexed sections were scanned using an Akoya multispectral scanner. An image analysis workflow using InForm and Matlab was developed to overcome challenges inherent to the DLBCL environment. Using the assays and workflows detailed here, we were able to quantify cell densities of subsets of infiltrating immune cells and observe their spatial patterns within the tumors. We highlight heterogeneous distribution of cytotoxic T cells across tumors with similar T cell density to underscores the importance of considering spatial context when studying the effects of immunological therapies in DLBCL.