The description also provides biomarkers, a change in one or more of which indicate that an Antibody anti CD200 has been an immunomodulatory effect desired in a Mammal. Mention is also Pharmaceutical compositions, kits, and Solutions containing at least one Antibody anti CD200 and are useful in the methods described herein.Claim 1: a method to Prolong the survival of renal allograft. The Method comprises administering to a Mammal in need a receiver that CD200 Antibody as a Single Agent in an amount and often effective to Prolong the survival of allograft ren In the mammalian host.Claim 32: The Method according to claim 21 to 25, which Selects at least one of one or more immunosuppressive agents of the group consisting of adriamycin, cyclophosphamide, azathioprine, cyclosporine a, Busulfan, Fludarabine, 5-fluorouracil, methotrex Ate, mycophenolate mofetil, mycophenolate Sodium is a non steroidal anti-inflammatory Drug,Rapamycin and tacrolimus.The Method of claim 47: According to any one of claims 1 to 46, where the body is selected from the group consisting aloinjertado in kidney, Lung, Heart, pancreas, Liver vascular tissue, or one or more lobes of this Eye tissue, Skin, gastrointestinal, Gastr Or nervous tissue, Muscle, Bone or cartilage, Bone Marrow, connective tissue cells, red blood cells, IsletsCornea and lens of the eye. The Method of claim 61: According to any one of claims 1 to 60, where the Antibody anti CD200 is a Human Antibody, Chimeric Antibody, Humanized Antibody, Antibody of Rodent, an Antibody or an Antibody desinmunizado primatizado.The Method of claim 62: According to any one of claims 1 to 59 or 61, in which the Antibody anti CD200 is a fragment of CD200 Antibody fixation to a complete anti CD200.Claim 81: The Method according to claim 67, which Selects at least one of one or more immunosuppressive agents of the group consisting of adriamycin, cyclophosphamide, azathioprine, cyclosporine a, Busulfan, Fludarabine, 5-fluorouracil, methotrexate, myco