A 47 year old man comes to GP because of an unusual mole. First noticed lesion a few months ago and paitent reports it seems to be larger at this time. Physical exam shows an 8 mm lesion that is asymmetrical and contains multiple shades of red, blue and black. Skin biopsy shows invasive melanome. PET/CT scan shows diffuse metastasis. He is given a therapy designed to combat T cell exhaustion. 1. Which molecule is likely target of this therapy?

Connective tissue is the most abundant type of tissue in the body. It serves to connect and support other tissues and also has regulatory and immunologic functions. Connective tissue consists of cells, mainly fibroblasts, and an extracellular matrix (ECM).