Comparative Immunogenomics of Canine Natural Killer Cells as Immunotherapy Target

Abstract

Natural killer (NK) cells are key effectors of the innate immune system, but major differences between human and murine NK cells have impeded translation. Outbred dogs offer an important link for studies of NK biology and immunotherapy. We analyzed gene expression of putative NK populations from healthy dogs and dogs with naturally-occurring cancers examining differential gene expression across multiple conditions, including steady-state, in vitro activation with cytokines and co-culture, and in vivo activation with inhaled IL-15 in dogs receiving IL-15 immunotherapy. We also compared dog, mouse and human CD3-NKp46+ NK cells using a novel orthologous transcriptome. Distinct transcriptional profiles between NK populations exist between conditions and in vitro versus in vivo treatments. In cross-species analysis, canine NK cells were globally more similar to human NK cells than mice. These data define canine NK cell gene expression under multiple conditions and across species, filling an important gap in translational NK studies.

Examination of IgG Fc Receptor CD16A and CD64 Expression by Canine Leukocytes and Their ADCC Activity in Engineered NK Cells

“…The study of ADCC in rodent syngeneic tumor models is limited by species differences in immune cell effector functions, including significant differences in human and mouse CD16 expression and function (see Introduction). The dog spontaneous cancer model incorporates heterogeneous disease and an intact immune system with many similarities to humans to help determine the mechanisms that underlie success and failure of immunotherapies (24)(25)(26). We have extended the current understanding of the dog immune system by demonstrating phenotypic and functional characteristics of canine CD16A and CD64 to advance utilizing these FcgRs for therapeutic approaches.…”

“…An ideal animal model for understanding the mechanisms that underlie success and failure of human immunotherapies should incorporate heterogeneous spontaneous disease and an intact immune system that is similar to humans. A comparable incidence of human and certain canine malignancies, combined with their shared biologic and pathologic characteristics, and similar response to therapy indicate that dogs can provide a clinically relevant disease model ( 24 – 26 ).…”

“…Based on morphology, canine NK cells are medium to large lymphocytes with electron-dense intracytoplasmic granules that contain granzyme B and perforin. These cells express at the mRNA level several genes associated with NK cells, such as NK1.1, NKG2D, CD94, CD96, NKp30, NKp44, NKp46, NKG2D, CD16A, DNAM-1, perforin, and granzyme B (26,27), and based on transcriptome analysis, canine NK cells are globally more similar to human NK cells than to mouse NK cells (26). Canine NK cells also mediate natural cytotoxicity and ADCC (27)(28)(29)(30)(31)(32).…”

Transcriptome Analysis of Tumor-Infiltrating Lymphocytes Identifies NK Cell Gene Signatures Associated With Lymphocyte Infiltration and Survival in Soft Tissue Sarcomas

“…Cells were processed for RNA isolation using the Total RNA Purification Plus Micro Kit (Norgen Biotek, Ontario, Canada). RNAseq libraries were prepared by the University of California, Davis, Bioinformatics Core ( 11 ). Gene expression profiling was carried out using a 3’-Tag-RNA-Seq protocol.…”

Comparative Evaluation of Tumor-Infiltrating Lymphocytes in Companion Animals: Immuno-Oncology as a Relevant Translational Model for Cancer Therapy

“…Regardless, the repertoire of immune markers and the homology of both myeloid and lymphoid populations between species has been described elsewhere [ 54 , 55 ]. Transcriptomic analysis of canine natural killer (NK) and myeloid-derived suppressor cells (MDSC) has provided further evidence of similarities between species [ 56 , 57 ]. Canine NK cell transcriptional changes appear to be more representative of human than mice in several different environments [ 57 ].…”