Frequently Asked Questions - Cell Biology
All human adult blood cell products are tested for HIV-1, HIV-2, and HCV antibodies and for Hepatitis B surface antigen and HIV-1 core antigen by FDA approved tests.
Yes. Source leukocytes are the residues of plateletpheresis of one human adult donor.
Our mononuclear cell preparations are enriched for lymphocytes and monocytes. Monocytes represent 15-40% of the population. The remaining fraction consists of 15-40% B-cells, and 60-85% T-cells.
Elutriated monocyte suspensions are >90% pure when analyzed by a variety of techniques. ABI documents purity during the elutriation process by multisizer analysis of purified monocytes, using statistical data to establish that >90% of the cell population has a mean cell size that is greater than small monocytes (approximately 8.5 microns). Final purity is confirmed by CD14 cell surface antigen distribution using immunofluorescence (IFA), with CD15 antigen tested by IFA as a control marker for granulocytes, which typically account for the majority of contaminating white blood cells in monocyte fractions. ABI customers with access to flow cytometry equipment have repeatedly confirmed ABI's monocyte purity estimates by this sensitive and reliable method.
ABI recommends seeding a minimum of 4 x 105 monocytes per cm2, to as many as 8 x 105 monocytes per cm2. Then follow our culture recommendations that are provided with shipment to establish mature macrophage monolayers.
No. Trypsin or Trypsin-EDTA will not work to detach and disperse macrophages. Macrophages are terminally differentiated cells that are limited in their ability to be subcultured or expanded. The cells can be gently scraped and passaged, but many cells will not re-attach and cell division will not occur to yield confluent, mature monolayers. Therefore, it is best to plate the number of vessels (plates, flasks, etc.) needed and to plan NOT to subculture them.
Following our growth and handling recommendations, macrophage cultures can survive for 45-60 days before senescence. Cultures are most metabolically active up to about 30 days after seeding.
Although successful cryopreservation and retrieval of functional macrophages have been documented in the literature, it is our experience that such manipulations give variable results and would not be recommended as a reliable method for ongoing research experiments (other than for research on the cryopreservation of macrophages).