Research Group

  • Dr Andrea Zachary, Principal Investigator
  • Dr Keith Melancon, Co-Investigator
  • Dr Mary Leffell, Co-Investigator
  • Dr Dessislava Kopchaliiska, Research Associate


  • Johns Hopkins University, Baltimore, USA


  • Detecting Humoral Sensitization

Patients may become sensitized to the transplantation antigen, called HLA antigens, through pregnancy, transfusion and transplantation. Once sensitized, these patients have greater difficulty finding a compatible donor and generally wait longer for a transplant. The frequencies of sensitized patients are higher in women and African-Americans. However, the evidence of sensitization, antibody against HLA, may diminish over time making it difficult to recognize that a patient is sensitized. When this happens, a patient may have an unexpected rejection episode that can damage the transplanted organ.

We hope to address the problems of unrecognized sensitization as well as investigate why African-Americans have higher rates of sensitization, using a technique developed in the Immunogenetics Laboratory at the Johns Hopkins University. This technique places a label on the cells responsible for the antibody to HLA and provides an opportunity to count them and characterize them. Thus, we may be able to determine if there is a certain number of such cells that predicts that a patient will have a rejection episode after transplantation. It may also allow us to identify differences between African-Americans and Caucasians that account for the higher rates of sensitization among African-Americans. In turn, this information may provide the opportunity for early intervention that could extend the life of a transplanted organ and improve the chances for a sensitized patient to be transplanted successfully.

Final Report