IJCEM Copyright © 2008-All rights reserved. Published by e-Century Publishing Corporation, Madison, WI 53711
Int J Clin Exp Med 2013;6(2):119-125

Original Article
Histological characterization of bone marrow in ectopic bone, induced by
devitalized Saos-2 human osteosarcoma cells

Niru N Nahar, Sarah E Tague, Jinxi Wang, Marsha Danley, Rama Garimella, H Clarke Anderson

Departments of Pathology and Laboratory Medicine, Molecular and Integrative Physiology, Orthopedic Surgery, Internal Medicine,
Dietetics and Nutrition, The University of Kansas Medical Center, Kansas City, KS, USA

Received December 16, 2012; Accepted January 14, 2013; Epub January 26, 2013; Published February 6, 2013

Abstract: Devitalized Saos-2, cultured human osteosarcoma cells, or guanidinium-hydrochloride (GuHCl) extracts of these cells,
induce ectopic bone and marrow formation when implanted subcutaneously in Nu/Nu mice. The aim of the present study was to
characterize the bone marrow induced by Saos-2 cell extracts, specifically to determine which of the four major hematopoietic cell
lineages: erythropoietic, granulopoietic, lymphopoietic and megakaryocytic, are induced by Saos-2 cell derivatives. Methods:
Immunohistochemical localization of specific antigens was used to determine the presence of each major cell type (glycophorin A for
erythropoietic, neutrophil elastase for granulopoietic, factor-VIII related antigen for megakaryocytes, and CD79a for B lymphocytes).
Results: Standard H & E stains confirmed the presence of normally organized apparently complete bone marrow within all newly
induced bone at 3 weeks post-implantation of devitalized Saos-2 cells. Immunohistochemistry confirmed the presence of erythropoietic
cells, granulopoietic cells, megakaryocytes and B lymphocytes in the ectopic marrow. Conclusion: Saos-2 cells (freeze-dried) or their
extracts, implanted subcutaneously into Nu/Nu mice, can induce normal marrow that is host-derived, and contains all major
hematopoietic cell lineages. Clinical Significance: Saos-2 induced marrow could potentially restore deficient marrow and promote
bone repair. (IJCEM1212004).

Keywords: Bone marrow induction, bone tumors, hematopoiesis, lineage-specific biomarkers, osteosarcoma

Address correspondence to: Dr. H Clarke Anderson, Department of Pathology and Laboratory Medicine, The University of Kansas
Medical Center, Kansas City, KS 66160. Tel: (913)-5887474; Fax: (913)-5887073; E-mail: handerso@kumc.edu or Dr. Rama Garimella,
Department of Internal Medicine, School of Medicine (Primary), Departments of Orthopedic Surgery, School of Medicine; and Dietetics
and Nutrition, School of Health Professions (Secondary), The University of Kansas Medical Center, Kansas City, KS 66160. Tel:
(913)-9456658; Fax: (913)-5883995; E-mail: rgarimella@kumc.edu