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This article presents a critical analysis of the use of biometrics in clinical practice and their inadequacies for Indigenous populations in Canada and globally. Misclassifications of health status based on biometrics have health implications across the lifespan, from gestation to older adulthood, which are also examined. The social determinants of health and of Indigenous health compound the impact of inaccurate biometrics on First Nations, Inuit and Métis populations. Moving forward, biometric use should be done in partnership with Indigenous peoples and with consideration of the surrounding context. Future research should consider bridging existing gaps in knowledge on this topic in culturally safe ways, to improve the quality and depth of information available and inform more equitable health care for Indigenous populations.

Dendritic cells (DC) have been implicated in the defective function of the immune system during cancer progression. We have demonstrated that patients with cancer have fewer myeloid (CD11c+) and plasmacytoid (CD123hi) DC and a concurrent accumulation of CD11c−CD123− immature cells expressing HLA-DR (DR+IC). Notably, DR+IC from cancer patients have a reduced capacity to stimulate allogeneic T-cells. DR+IC are also present in healthy donors, albeit in smaller numbers. In this study, we assessed whether DR+IC could have an impact on the immune response by comparing their function with DC counterparts. For this purpose, DR+IC and DC were purified and tested in the presentation of antigens through major histocompatibility complex (MHC) II and MHC-I molecules. DR+IC were less efficient than DC at presenting antigens to T-cells. DR`IC induced a limited activation of T-cells, eliciting poor T-helper (Th) 1 and preferentially inducing Th2-biased responses. Importantly, despite DR+IC's poor responsiveness to inflammatory factors, in samples from healthy volunteers and breast cancer patients, CD40 ligation induced phenotypic maturation and interleukin 12 secretion, in turn generating more efficient T-cell responses. These data underscore the importance of inefficient antigen presentation as a mechanism for tumor evasion and suggest an approach to improve the efficacy of DC-based immunotherapy for cancer.

Dendritic cell (DC) defects are an important component of immunosuppression in cancer. Here, we assessed whether cancer could affect circulating DC populations and its correlation with tumor progression. The blood DC compartment was evaluated in 136 patients with breast cancer, prostate cancer, and malignant glioma. Phenotypic, quantitative, and functional analyses were performed at various stages of disease. Patients had significantly fewer circulating myeloid (CD11c+) and plasmacytoid (CD123+) DC, and a concurrent accumulation of CD11c−CD123− immature cells that expressed high levels of HLA-DR+ immature cells (DR+IC). Although DR+IC exhibited a limited expression of markers ascribed to mature hematopoietic lineages, expression of HLA-DR, CD40, and CD86 suggested a role as antigenpresenting cells. Nevertheless, DR+IC had reduced capacity to capture antigens and elicited poor proliferation and interferon-γ secretion by T-lymphocytes. Importantly, increased numbers of DR+IC correlated with disease status. Patients with metastatic breast cancer showed a larger number of DR+IC in the circulation than patients with local/nodal disease. Similarly, in patients with fully resected glioma, the proportion of DR+IC in the blood increased when evaluation indicated tumor recurrence. Reduction of blood DC correlating with accumulation of a population of immature cells with poor immunologic function may be associated with increased immunodeficiency observed in cancer.