Also known as T lymphocytes, T cells are white blood cells that participate in a variety of cell-mediated immune reactions. Three fundamentally different types of T cells are recognized: helper, killer, and suppressor. CD4 cells are also known as T helper cells, whereas CD8 cells are one type of T killer cells. T cells are essential for a normal functioning immune system. The “T” stands for the thymus, where T-cells mature.


Learn more about HIV


Get more information about living with HIV

Get Tested

Find testing and prevention resources


A collection of answers and resources

We’re here to connect you to the information and resources you need.

Do you have questions about HIV? Do you want to know more about testing, connecting to care, or how to show support? Are you interested in learning more about how SIDE BY SIDE can help your community? Fill out this contact form and someone from our team will be happy to help you find answers.


Please be sure to include your preferred method of contact. We respect your privacy and we do not share your information without your permission