Investigating Cell Surface Markers on Normal Hematopoietic Stem Cells in Three Different Niche Conditions

Abstract

Hematopoietic stem cells are of therapeutic interest to the clinicians and researchers due to their promising assistance in management of malignant and inherited hematological conditions. Evaluation of cell surface markers using multiparametric flow cytometry is a well adapted qualitative measure of cells in question for many years. An artillery of these markers has been studied in hematological malignancies and related disorders. However, their role and differential expression on normal hematopoietic stem cells from clinically available sources is not always described carefully. In the present study, we attempted to evaluate expression of CD44, CD90, CD96 and CD123 in three clinically available sources of normal HSCs (Hematopoietic stem cells). Sources of HSCs in the present study involved umbilical cord blood (UCB), normal bone marrow (NBM) and bone marrow from idiopathic thrombocytopenic purpura (ITP) patients (IBM). CD44 is an important homing receptor while CD90 is involved in maintaining stem cell quiescent. CD96 is known to be leukemia specific marker and CD123 is involved in stem cell differentiation and survival. We observed a significant difference in expression CD44, CD90 and CD123 on normal HSCs derived from umbilical cord and ITP marrow. CD96 was highly expressed on HSCs obtained from ITP marrow. Investigating expression of these markers on normal HSCs in different niches will be helpful in correlating their function with niche condition and delineating their 'abnormal' expression from the normal.

Differential antigen expression and aberrant signaling via PI3/AKT, MAP/ERK, JAK/STAT, and Wnt/β catenin pathways in Lin−/CD38−/CD34+ cells in acute myeloid leukemia

“…Antibodies were titrated for maximum signal‐to‐noise ratio on cells from normal peripheral blood and bone marrow. Side scatter low, CD45 dim‐to‐negative, Lineage‐negative, CD38‐negative, and CD34‐positive population in AMLs and on normal samples were carefully gated using fluorescence minus one (FMO) tubes as described earlier . Primary gating panel included monoclonal antibodies: anti CD45APC‐Cy7, CD38FITC, CD34PECy7 form BD biosciences (San Jose, CA, USA) and human hematopoietic Lineage cocktail (including anti CD2, CD3, CD14, CD16, CD19, CD56, and CD235a) from Ebiosciences (San Diego, CA, USA).…”

Molecular Pathways: Targeting CD96 and TIGIT for Cancer Immunotherapy

“…CD96 expression, ligand interactions, and putative signaling pathways CD96 (TACTILE) was first identified as an Ig superfamily receptor (26); however, it is now known to be a member of the extended nectin/NECL family, and its role in immune function has received little attention until recently. CD96 expression is broadly similar between mice and humans, and is present on a proportion of hematopoietic stem cells, ab and gd T cells, NK cells, and a subpopulation of B cells in humans (27)(28)(29)(30)(31) and present on ab and gd T cells, NK cells, and NKT cells in mice (11,32). CD96 is not expressed on other immune cells, and expression is generally low or absent in organs without lymphocyte infiltrate (29).…”

Spleen as a Site for Hematopoiesis

“…Staining for Thy1.2 revealed restricted distribution of T cells, mainly in the white pulp regions of adult and neonatal spleens. While Thy1.2 has been reported to be a Pan-T cell marker, several other cell types including HSC, mesenchymal stem cells and fibroblastic cells are also known to express this marker (Garg et al, 2013;Nagasawa et al, 2011;Dominici et al, 2006;Spangrude et al, 1988). These cells are rare however, and it was not possible to distinguish them using immunohistochemical staining of frozen sections.…”

“…These included CD140a/b which identifies fibroblastic reticular cells, red pulp fibroblasts, CAR cells and MSC (Mueller and Germain 2009;Nagasawa et al 2011), CD51 which identifies CAR cells (Nagasawa et al, 2011), as well as Thy1 which identifies T cells and MSC (Garg et al, 2013;Nagasawa et al, 2011;Dominici et al, 2006;Spangrude et al, 1988). By using a combination of markers for stromal and hematopoietic cell types, it has been possible to localise different stromal cell subtypes in relation to hematopoietic stem/progenitor cells.…”