What is the difference between your cd3 and CD4 cells?

T-cells. All t-cells in the blood have the cd3 marker on their surface. In addition to having cd3 on them, most t-cells have either cd4 (if they are helper t-cells; th2-like) or cd8 (if they are cytotoxic t-cells; th1-like). There are many other types of t-cells (nkt, th17, treg, tr1, tfoll, th9) that make up a small number of the circulating t-cells. All of these t-cells have cd3 on them as well.
Types... Cd3 and cd4 cells are different types of t-cells. T-cells are part of your immune system.