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K Garner

Publications and source records attributed to K Garner.

3 recordsLinked to original sources

Rapid detection of leukemia-associated translocation fusion genes using a novel combined RT-PCR and flow cytometric method.

Efficient detection of recurrent translocation-associated fusion genes is of critical importance for the diagnosis, prognosis and post-therapeutic monitoring of many leukemias. Typically, the presence of such translocations is revealed by RT-PCR technique, followed by Southern blot hybridization to ensure specificity of the PCR product. Though widely employed, post-PCR analysis of this type is relatively laborious and time-intensive. As a departure from standard analytic approaches, we have developed a robust novel method combining both high specificity and sensitivity, based on polystyrene bead capture of fluorescently labeled PCR products, with subsequent analysis by flow cytometry. Results from cell line and patient sample evaluations indicate that this method may be easily incorporated into the diagnostic molecular laboratory as a rapid and cost-effective alternative to currently employed techniques.

Adult↗

MHC class II molecules transferred between allogeneic dendritic cells stimulate primary mixed leukocyte reactions.

Presentation of antigen to T cells is generally restricted by MHC type but the mixed leukocyte reaction (MLR) was thought to involve direct stimulation by dendritic cells (DC) of allogeneic T cells. However, here we showed that DC bearing allogeneic MHC class II acted synergistically with responder-type DC. Removal of residual DC from 'purified' responder T cell populations was achieved using treatment with DC-specific antibody and complement. These DC-depleted cells showed a significantly reduced response to allogeneic DC which was restored by addition of DC syngeneic with responder T cells. The studies support the concept that a major component of the MLR is the secondary presentation of alloantigens acquired from stimulator DC by DC of responder type. To investigate the reasons why DC and not other cells stimulate an MLR, synergy between DC and other cell types was investigated. Synergy was found exclusively between DC; macrophages, B cells or L cells transfected with MHC class II molecules did not contribute. When allogeneic DC were mixed in culture, transfer of MHC molecules between DC was observed as assessed by flow cytometry. Freshly obtained cell-free supernatants from cultured DC contained MHC class II and stimulated primary allogeneic MLR. DC of responder type acquired allogeneic MHC molecules from the supernatants and stimulated proliferation in syngeneic T cells. The capacity of DC both to shed and to acquire MHC molecules may contribute to their potency in stimulating primary responses, and could explain why passenger DC within allografts provide a potent stimulus for graft rejection.

Animals↗