CTLA4 or CTLA-4 (cytotoxic T-lymphocyte-associated protein 4), also known as CD152 (cluster of differentiation 152), is a protein receptor that, functioning as an immune checkpoint, downregulates the immune system. CTLA4 is found on the surface of T cells, and acts as an "off" switch when bound to CD80 or CD86 on the surface of antigen-presenting cells.
The CTLA-4 protein is encoded by the Ctla4 gene in mice and the CTLA4 gene in humans.
CTLA4 is a member of the immunoglobulin superfamily that is expressed on the surface of Helper T cells and transmits an inhibitory signal to T cells. CTLA4 is similar to the T-cell co-stimulatory protein, CD28, and both molecules bind to CD80 and CD86, also called B7-1 and B7-2 respectively, on antigen-presenting cells. CTLA4 transmits an inhibitory signal to T cells, whereas CD28 transmits a stimulatory signal. Intracellular CTLA4 is also found in regulatory T cells and may be important to their function. T cell activation through the T cell receptor and CD28 leads to increased expression of CTLA-4, an inhibitory receptor for B7 molecules.
[Verse:]
He gave his baby boy a bath
Tub full of bubbles and toys for him to splash
Look at daddy, soapsuds mustache
Funny faces and voices, it makes the baby belly laugh
Dry him off, now you squeaky clean
And watch the water spiral down that drain
Wrap him in a towel so he doesn't get the shivers
Brush his hair, it seems to help it dry it quicker
Laid him on mommy and daddy's bed now that he's dry
And put a diaper on him, gave him his pacifier
Superman pajamas, so tough
Innocent face full of unconditional love
Daddy picked him and rocked him slow
Never takes long for little guy's eyes to close
Dad's technique is different than your mother's
Never learned any lullabies, he sings Stevie Wonder's
There it is, steady breathing, sleep rhythm
Daddy sits and holds him just to listen for a minute
Daddy's hands are the meaning of security
And baby's hands are the evidence of purity
Thinking back to the day baby came
And how it changed the whole game, things ain't the same
Daddy had to stop running it crazy
Keep his ass in the home with the son and his lady
He was there for the birth and the first breath
Not gonna miss the first words or the first steps
Gonna keep the boy healthy and safe
And do his best to try to keep those tears off his face
Gave him a kiss, laid him in his crib
Turned out the lights, goodnight my little prince
That's how good daddy takes care of him