About CD4
This gene encodes the CD4 membrane glycoprotein of T lymphocytes. The CD4 antigen acts as a coreceptor with the T-cell receptor on the T lymphocyte to recognize antigens displayed by an antigen presenting cell in the context of class II MHC molecules. The CD4 antigen is also a primary receptor for entry of the human immunodeficiency virus through interactions with the HIV Env gp120 subunit. This gene is expressed not only in T lymphocytes, but also in B cells, macrophages, granulocytes, as well as in various regions of the brain. The protein functions to initiate or augment the early phase of T-cell activation, and may function as an important mediator of indirect neuronal damage in infectious and immune-mediated diseases of the central nervous system. Multiple alternatively spliced transcript variants encoding different isoforms have been identified in this gene. [provided by RefSeq, May 2020]

About PerCP-Vio700
PerCP-Vio® 770 is a far-red-emitting tandem fluorophore that combines PerCP and a Vio®770 dye. The donor, PerCP, can be excited by the 488 nm blue laser and transfers energy to the acceptor, Vio®770, which emits light that can be captured with a 780/60 nm bandpass filter. APC-Vio®770 has an excitation peak at 482 nm and an emission peak at 704 nm, and is spectrally similar to PerCP-Cy5.5 and PerCP-eF710. PerCP-Vio®770 is known to be very bright and photostable, as well as being stable when treated with fixatives. These favorable characteristics that make it useful in multiple different applications such as flow cytometry and Fluorescence Microscopy. The large stokes shift can be advantageous when trying to fit more colors into a multicolor panel. The Vio® dye family are products of Miltenyi Biotec, with many antibody conjugates designed and validated for flow cytometry.