CFU Protocols

Colony-forming unit, or CFU, is a measure of microorganism numbers. Unlike other methods, such as direct microscopic where dead and living microorganisms are considered, CFU protocols enables biologists to count only viable cells. Standard measure units are colony-forming units per milliliter for liquids and colony-forming units per gram for solids. CFU protocols are widely used in biotechnology research.

CFU-MK Assay for Acute Thrombocytopenia Protocol

• Megakariocyte, or MK, is a type of bone marrow cell that produces platelets. This protocol is used in studies about thrombocytopenia, a condition related to low platelet numbers. Prior to the counting, technicians prepared the CFU- MK assay with human cord blood cells, Iscove's modified Dulbecco's medium, bovine collagen solution, serum-free medium with proteins called cytokines, antibodies anti-TNP, anti-GPIIb/IIIa and anti--mouse IgG, Evans blue counterstain, Tris/NaCl buffer and bovine serum albumin.

Colony Assay Mix Protocol

• Technicians prepare this assay with human plasma, the chemical 2-mercaptoethanol, leukocyte conditioned media, the hormone erythropoietin and Iscove's Modified Dulbecco's medium, according to Jeffrey W. Pollard in "Basic Cell Culture Protocols." This solution is then mixed with the cell samples to be analyzed. Methylcellulose is added, and the samples are incubated in an humidified atmosphere with 5 percent carbon dioxide for 14 days.

Migration of CFU in CD34 Cells

• CD34, or cluster of differentiation molecules, are present on certain human immunodefense cells, acting as controlled adhesion factor on the cellular membranes. Cells containing this protein can have the ability to migrate from one tissue to the other. During this protocol, technicians wash samples of CD34 migrated cells to remove cytokynes proteins. Samples are then centrifuged and re-suspended in a medium containing grow factors. Colonies are counted two weeks later.