Cytomark Ltd

Cytomark is a manufacturer of high quality reagents for Flow Cytometry. The company was formed in 2004 to offer products developed by UK NEQAS.

Through a unique cooperation with Sheffield Teaching Hospital Trust, Cytomark has brought to market a range of products based on research developments scientists at UK NEQAS.

Cytomark is a biotechnology company that produces flow cytometry reagents; TransFix - a cellular stabilisation solution and Blood Controls.

TransFix is a patented, CE marked stabilisation solution that prevents cellular degradation in human and animal blood for analytical testing purposes.
The active components of TransFix stabilise leukocytes and leukocytic antigens for up to 10 days at sample storage temperatures of between 2-25°C and for 4 days at temperatures between 25-37°C.

Cytomark CD4 Blood Controls are controls designed to contain normal (CD4 Normal Blood Control) and low (CD4 Low Blood Control) levels of CD4+ T cells in whole blood, whilst maintaining a normal whole blood forward/side scatter profile on flow cytometry.

- TransFix®: A Cellular Antigen Stabilisation Reagent.
TransFix is a patented, CE marked stabilisation solution that prevents cellular degradation in human and animal blood for analytical testing purposes.
TransFix is validated for the stabilisation of whole blood for flow cytometric analysis. The active components of TransFix stabilise leukocytes and leukocytic antigens for up to 10 days at sample storage temperatures of between 2-25°C and for 4 days at temperatures between 25-37°C. TransFix is added to samples at the time of collection enabling their storage and transportation at room temperature. This allows greater flexibility in testing and the potential for cost reduction by allowing samples to be batched.. The immunophenotypic profile of surface markers including CD3, CD4, CD8 and CD45 is maintained following the addition of TransFix to whole blood. TransFix is available in multiple formats: direct draw vacuum blood collection tubes, Blood or CSF sample storage tubes and bulk volumes.

Blood Controls for Flow Cytometry
The quantitation of CD4+ cells by flow cytometry is a vital tool in evaluating human immunodeficiencies. Cytomark have developed two stabilised preparations of human blood with known lymphocyte absolute counts including CD4+ cells. They are intended for use as daily run controls in blood sample analysis for the verification of monoclonal antibody and FACS reagents, validation of flow cytometer performance, verification of red blood cell lysis and validation of operator technique. CD4 Blood Controls are available in two formats; CD4 Normal - >700 cells/µl and CD4 Low - between 200 and 300 cells/µl.