Peripheral blood mononuclear cells, which are also called PBMCs or
PB-MNCs, are blood cells that have round nuclei. They are critical to
immune system functioning; they fight infection and foreign intruders in
the body. Lymphocytes, monocytes and phagocytes are three examples of
peripheral blood mononuclear cells.
Lymphocytes are white blood
cells found in the immune system of vertebrates, animals with spinal
columns and backbones. A scanning electron microscope (SEM) image can
reveal a division between large and small lymphocytes.
Large
lymphocytes are known as natural killer cells or NK cells. These PBMCs
are the first line of defense against infection. Small lymphocytes
include B cells and T cells, which play important roles in both antibody
and non-antibody response.
Like lymphocytes, monocytes are white
blood cells found in the vertebrate immune system. They are present in
humans, mammals, birds, fish and reptiles. These peripheral blood
mononuclear cells have multiple roles in immune system functioning. They
produce and replenish various immune cells, and they respond to
inflammation and infection signals.
Monocytes are produced in the
bone marrow. Half of these monocytes are stored within the spleen. Those
that migrate from the bloodstream to other tissues mature into
different cell types, including macrophages.
Macrophages are
essentially cells that monocytes produce in the tissues. Both
macrophages and monocytes are phagocytes, another type of white blood
cells. They offer immune protection through the ingestion of bacteria,
dying cells and foreign particles.
Phagocytes are highly developed
in vertebrates, especially humans. One liter of human blood contains
nearly six billion of these phagocytes. Similarly to other white blood
cells, they are highly critical for fighting infection, removing dead
cells and maintaining healthy tissue.
Peripheral blood mononuclear
cells have wide-ranging uses, from scientific research and clinical
studies to cellular therapy. Healthy donors can give their blood cells
for the testing of blood-borne pathogens. Donor cells are important to
the study of HIV, Hepatitis B, syphilis and other infectious and
auto-immune diseases. PBMCs are also used for vaccine development.
PBMCs
are also vital to cellular therapy, a process that introduces new blood
cells into damaged tissue to treat a particular disease. This type of
therapy often focuses on hereditary diseases and may include gene
therapy, stem cell treatments and cell replacement therapy.