Effects of Thymoglobulin on Human B Cells

Patients will be asked to provide blood for immune tests.Patients will not take any study medications, all the research will be performed on blood donated for the study.Patients will donate about 20mls of blood (2 tbls)to be used to determine the subject's blood group and tissue typing (genetic).Results and the patient's contact information will be maintained in a database that is accessible only by the investigators and study personnel conducting the study.For the duration of this study, the investigator will contact patients by phone to request additional samples when needed. Study staff may ask patients donate more blood on short notice (1 day). This will consist of 60-120 ml (6-12 tbls) of blood.The frequency of blood collection will not exceed more than 2 times per week.The total amount of blood collected from subjects will not exceed 360 ml (1.5 cups) within any eight week period throughout the two year timespan patients may be asked to participate in this study.