09a: Bone Marrow Histo

Why is analyzing a postmortem bone marrow biopsy difficult

Bone marrow autolyzes FAST

Key process that happens in bone marrow

Hematopoiesis

Indications for extramedullary hematopoiesis

Young animals or bone marrow is unable to keep up

Stages of RBC development that we typically find in the blood

Mature RBCs, and occasionally reticulocytes

Types of bone marrow

• Red: hematopoietic

• Yellow: higher adipose content

Common location of red bone marrow

Larger bones

Factor that affects the amount of yellow marrow in the body

Based on the animal’s metabolic demand

T/F: red marrow is a mix of blood cells and fat cells

True

In which animal demographic is it normal to see much less yellow marrow than red marrow

Young animals → they need the metabolic support of all those RBCs, and also haven’t had the chance to store a lot of fat

Why is it not great if immature cells are released into circulation

• They don’t function right

• They can end up attacking self cells, inducing a hypersensitivity reaction

Type of capillaries found in bone marrow

Sinusoidal/discontinuous

Type of blood cell precursor that can become anything

Totipotent cells

Type of blood cell precursor that can become a handful of cell types

Pluripotent cells

Type of blood cell precursor that is the “true” progenitor cells

Multipotent cells

Morphological features of a megakaryocyte

LARGE cell with multiple nuclei

Reasons to run a bone marrow sample on a live patient

• Peripheral blood abnormalities

• Cancer staging

• Evaluating iron stores

Reasons to run a bone marrow sample on a dead patient

Basically just to evaluate yellow marrow stores when starvation and neglect are suspected