CD3/CD4/CD8/CD45 Detail

The CD3/CD4/CD8/CD45 test is a flow cytometry-based assay that quantifies different subsets of T-lymphocytes in the peripheral blood. These markers help assess the functional state of the immune system, particularly in conditions like HIV infection, autoimmune diseases, organ transplantation, and other immune disorders.

Marker Descriptions:

• CD3:
  A marker found on all mature T-cells. It is used to measure the total T-cell count.

• CD4:
  Found on helper T-cells. These cells play a central role in coordinating immune response.
  CD4 count is critical in HIV monitoring – a declining count indicates disease progression and immunosuppression.

• CD8:
  Found on cytotoxic T-cells, which are involved in killing virus-infected or cancerous cells.
  CD8 levels are also monitored in HIV and immune activation.

• CD45:
  A pan-leukocyte marker present on all types of white blood cells. It is used as a gating marker in flow cytometry to distinguish leukocytes from other cells and debris.

Clinical Use:

• Monitoring HIV/AIDS patients: CD4 count helps determine the stage of disease, treatment response, and need for prophylaxis.

• Evaluating immunodeficiencies, such as SCID or post-transplant immune status.

• Assessing immune reconstitution in cancer therapy or bone marrow transplant patients.

• CD4/CD8 ratio is used to assess immune balance; a low ratio (<1) may indicate immune suppression or activation.