Anti-Icos Monoclonal antibody, clone 26G0 [PerCP-eFluor® 710]

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.

Patients with ulcerative colitis (UC) are at increased risk of developing colitis-associated colon cancer. Accumulating evidence suggests that follicular T helper (T-FH) cells play a crucial role in the pathogenic process of autoimmune diseases. However, little is known about the role of T-FH cells in the development of UC. To investigate the role of T-FH cells in the development of UC, the number of T-FH cells, the level of interleukin-21 (IL-21), the numbers of B cell subsets, and clinical parameters were detected in peripheral blood from 31 UC patients and 29 healthy controls. T-FH cells and the level of IL-21 were significantly higher in UC patients than in the healthy controls. A positive correlation between T-FH and IL-21 cells was found in UC patients. Moreover, aberrant frequencies of different subsets of B cells were observed in UC patients, and a positive correlation was found between CD38(+)CD19(+) B cells and T-FH cells and between CD86(+)CD19(+) B cells and T-FH cells. A high number of T-FH cells were positively associated with Mayo score, serum C-reaction protein (CRP) and serum IgG in UC patients. Our data indicate that T-FH cells and IL-21 are involved in the pathogenesis of UC.