Sequential measurement of peripheral blood allogeneic microchimerism levels and association with pulmonary function
McSherry, C.; Jackson, A.; Hertz, M.I.; Bolman, R.M.; Savik, K.; Reinsmoen, N.L.
Transplantation 62(12): 1811-1818
1996
ISSN/ISBN: 0041-1337 PMID: 8990369 Document Number: 464800
We have shown in lung recipients that high levels of peripheral blood allogeneic microchimerism at 12 to 18 months posttransplant correlated with donor antigen-specific hyporeactivity (i.e., decreased proliferative response to donor antigen in MLC while response to 3rd-party cells remains unchanged); both parameters correlated with an obliterative bronchiolitis (OB)-free state. We have expanded these studies to determine any association of sequential microchimerism levels with concomitant clinical events. In this preliminary study of 7 lung recipients, we used limiting-dilution PCR to quantify peripheral blood microchimerism at serial timepoints-ranging from 3 to gt 48 months posttransplant. These levels were compared with a variety of immunologic and clinical parameters: acute rejection, CMV infection, OB, donor antigen-specific hyporeactivity, and pulmonary function. Pulmonary function was measured per the International Society of Heart and Lung Transplantation: "current FEV-1/baseline FEV-1" (FEV-1: forced expiratory volume in 1 second). Of the clinical parameters, the association between microchimerism and pulmonary function was the most striking. We observed dynamic patterns of peripheral microchimerism, which reflected the general rise and fall of FEV-1. In all 7 recipients, chimerism and FEV-1 were high very early posttransplant, then dropped at various rates and to various degrees. After its initial decline, microchimerism increased with FEV, for the 1 hyporesponsive recipient; for the other 6 recipients, both values declined. These results illustrate, for the first time, that the fluctuation of peripheral blood microchimerism levels is associated with the recipient's clinical condition.