CD4+ Helper T cells are isolated from mononuclear cells by positive selection using immunomagnetic cell separation procedures. Peripheral blood cells are collected from normal human volunteers by direct collection or by using the COBE® Spectra or Spectra Optia® Apheresis System where cell-rich leukapheresis product is extracted using continuous flow centrifugal technology directly into the collection bag.

• Purity of >90% by flow cytometry
• Negative for Hepatitis B, Hepatitis C, HIV 1/2, HTLV-I/II, HIV-1/HCV/HBV nucleic acid, WNV nucleic acid, Trypanasoma cruzi and Syphilis
• Cryopreserved in CryoStor® CS10 media

CD4⁺ Helper T cells oversee the action of the human immune system; they are involved in activating and directing other immune cells. CD4⁺ Helper T cells are crucial in determining B cell antibody class switching, the activation and growth of cytotoxic T cells, and maximising bactericidal activity of phagocytes (i.e. macrophages).

Storage: Either prepare cells for long term storage in liquid nitrogen vapor phase or thaw for use. Storage in liquid phase nitrogen is NOT recommended. Short term storage of cells (less than 2 weeks) at −80 °C is acceptable, but should be minimised to ensure maximum stability. Once thawed, samples must be used immediately.