Illuminating immune privilege--a role for regulatory T cells in preventing rejection

Evaluation of proinflammatory and immunosuppressive cytokines in blood and bone marrow of healthy hematopoietic stem cell donors

INTRODUCTION

Cytokine composition of bone marrow microenvironment in comparison to blood is poorly explored. The goal of this study was to investigate the levels of cytokines present in peripheral blood and bone marrow of healthy hematopoietic stem cells donors. The data obtained on this subject with addition to cytometric analysis can provide new insight into the hematopoietic stem cells microenvironment.

METHODOLOGY

Study consisted of cytokine concentration analysis performed by ELISA tests of peripheral blood of healthy peripheral blood stem cells donors and bone marrow of healthy bone marrow donors. Additionally we have tested the expression of CD47 and CD274 proteins on the surface of hematopoietic stem cells by the flow cytometry analysis.

RESULTS

The results has shown different composition of analyzed cytokines (IL-1 β, IL-2, IL-4, IL-6, IL-10, IL-17A, TGF-β1, IFN-γ and TNF-α) present in bone marrow and blood of stem cells donors. The hematopoietic stem cells in peripheral blood are subjected to higher levels of proinflammatory cytokines whilst the lower level of those cytokines in bone marrow with a very high level of TGF-β1 which possibly creates a more immunosuppressive environment. The IL-10 level was significantly higher in peripheral blood of PBSC donors after the administration of mobilizing factor (G-CSF). The percentage of CD47+HSCs was significantly higher in bone marrow compared to peripheral blood of mobilized donors.

Multiple myeloma in the marrow: pathogenesis and treatments

Multiple myeloma (MM) is a B cell malignancy resulting in osteolytic lesions and fractures. In the disease state, bone healing is limited owing to increased osteoclastic and decreased osteoblastic activity, as well as an MM-induced forward-feedback cycle where bone-embedded growth factors further enhance tumor progression as bone is resorbed. Recent work on somatic mutation in MM tumors has provided insight into cytogenetic changes associated with this disease; the initiating driver mutations causing MM are diverse because of the complexity and multitude of mutations inherent in MM tumor cells. This manuscript provides an overview of MM pathogenesis by summarizing cytogenic changes related to oncogenes and tumor suppressors associated with MM, reviewing risk factors, and describing the disease progression from monoclonal gammopathy of undetermined significance to overt MM. It also highlights the importance of the bone marrow microenvironment (BMM) in the establishment and progression of MM, as well as associated MM-induced bone disease, and the relationship of the bone marrow to current and future therapeutics. This review highlights why understanding the basic biology of the healthy and diseased BMM is crucial in the quest for better treatments and work toward a cure for genetically diverse diseases such as MM.