Doc. MUDr. L. Boudová. Ph. D.
Bone marrow histology
Hematopoiesis – production of blood components
main organs involved:
bone marrow, lymph nodes, spleen; blood, lymph; also other organs (mucosa asociated
lymphoid tissue - GIT, respiratory tract...)
"slang" words
myeloid compartment– bone marrow and : ery, granulo, monocytes, platelets
(narrower sense of the word: myeloid only for the granulocytic series)
lymphoid – thymus, lymph nodes, spleen, lymphocytes
blast – a cell looking immature
sites of hematopoiesis – ontogenetic survey
postnatal life: in the BM - physiologically: almost only medullary
in other organs than in the BM: extramedullary - physiological situations - prenatally, minor
components short after birth; postnatally: pathological
Prenatal life: yolk sac , liver, bone marrow
Active BM in adults: axial skeleton, proximal epihyseal regions of the humerus and femur
bone marrow in other bones: only yellow fatty marrow
laboratory methods to examine disorders of the blood and bone marrow
blood count –blood smears –bone marrow smears (cytology)
histology of the bone marrow – aspirates, trephine biopsy
cytogenetic (appropriate medium!); molecular genetic examination
Normal histology of the bone marrow
bone: woven or lamellar(compact or trabecular)
I. Non-hematopoietic elements
Bone
1
Doc. MUDr. L. Boudová. Ph. D.
periosteum
cortex
solid layer of compact bone –
medulla
bony trabeculae – spongy - lamellar (surface: cortical compact bone)
endosteal cells,osteoblast, osteocytes
other non-hematopoietic components
fat cells; reticulin fibres; stromal cells
II. Hematopoiesis
the basic series: myeloid (most numerous in the BM – different to PB!), erythroid,
megakaryocytes, lymphoid cells
Origin and differentiation
common: pluripotent hematopoietic stem cell
lymphoid stem cell
trilineage stem cell
factors: thrombopoietin, erythropoietin, colony-stimulating factors, etc.
myeloid (ratio M:E: 3:1!) – granulocytes and monocytes
erythroid – dark islands
megakaryocytes (thrombopoiesis) – dispersed individually
lymphocytes – up to 10% of the bone marrow cells
IT IS ABSOLUTELY NECESSARY TO REMEMBER THE REFERENCE RANGES OF
THE PB ELEMENTS!!
2