Description

CD45.1 C57BL/6 Peripheral Blood Mononuclear cells (PBMCs)

CD45.1 PBMCs come from C57BL/6 congenic mice that express the CD45.1 allele.  CD45 itself is a protein tyrosine phosphatase receptor expressed on all hematopoietic cells except mature erythrocytes and platelets and is encoded by the Ptprc gene.  Wild-type C57BL/6 mice normally carry the Ptprc^b (CD45.2) allele while the other (congenic) strain carries the Ptprc^a (CD45.1) allele on the same C57BL/6 genetic background.

Application Summary for CD45.1 and CD45.2 Cells

CD45.1 and CD45.2 cells are widely used in transplant and adoptive transfer studies to track the donor and host cells through the different alleles.  In most transfer experiments, leukocytes expressing CD45.1 are transferred into wild-type C57BL/6 mice and then identified using an antibody specific for CD45.1.   Similarly, cells expressing CD45.2 can be distinguished using antibodies that recognize CD45.2.

Cells from congenic mice that are genetically engineered (knockout or transgenic mice) can also be used in in vitro experiments to track cell development.  Cells from knockout mice on a CD45.1 background can be mixed in culture with CD45.2 wild-type cells to understand the role of that specific gene in cell lineage fate decisions in a wild-type environment.  Similar to the animal studies, antibodies against CD45.1 and CD45.2 can be used to distinguish the origin of the cells and track their outcomes.  These experiments are faster and easier to perform and analyze compared to animal transfer studies.

Isolation of CD45.1 PBMCs

Peripheral blood collection and PBMC Isolation

PBMCs from non-human organisms are isolated from peripheral blood collected responsibly at third party facilities.  These facilities are vetted to ensure they operate according to local regulations and laws.  Since the facility is local, the blood is quickly transported to iQ’s facility for processing.

PBMCs are specifically isolated by performing a density centrifugation at room temperature to remove red blood cells.  iQ Biosciences performs this process under sterile conditions by using Ficoll, a high molecular weight sucrose solution from GE Healthcare.  The result is a perfect layer of mononuclear cells that are separated from plasma, platelets, granulocytes, and erythrocytes.  Additional quality control steps are taken to isolate and prepare PBMCs that ensure the highest viability for cryopreservation and downstream experimental applications.

Expression of CD45.1

A small aliquot of cells was tested for CD45.1 by flow cytometric analysis. Expression of CD45.1 was > 99%.

Cryopreservation and storage

CD45.1 PBMCs were cryopreserved carefully using iQ Biosciences’ cryopreservation protocol that ensures high viability (> 80%) after thawing.

Cells should be stored at <-120°C once they are received, such as within a liquid nitrogen tank (vapor phase).