Molecular and immunohistochemical characterization of the onset and resolution of human renal allograft ischemia-reperfusion injury.

BACKGROUND Following allotransplantation, renal ischemia-reperfusion (I/R) injury initiates a series of events that provokes counter-adaptive immunity. Though T cells clearly mediate allospecific immunity, the manner in which reperfusion events augment their activation has not been established. In addition, comprehensive analysis of I/R injury in humans has been limited. METHODS To evaluate the earliest events occurring following allograft reperfusion and gain insight into those factors linking reperfusion to alloimmunity, we examined human renal allografts 30 to 60 minutes postreperfusion (n=10) and compared them with allografts with normal function that had resolved their I/R injury insult (>1 month posttransplant, n=6) and to normal kidneys (living donor kidneys before procurement, n=8). Biopsies were processed both for immunohistochemical analysis as well as for transcript analysis by real-time quantitative polymerase chain reaction (RT-PCR). RESULTS Reperfusion injury was characterized by increased levels of gene transcripts known to be involved in cellular adhesion, chemotaxis, apoptosis, and monocyte recruitment and activation. T-cell-associated transcripts were generally absent. However, recovered allografts exhibited increased levels of T-cell and costimulation-related gene transcripts despite normal allograft function. Consistent with these findings, the immediate postreperfusion state was characterized histologically by tubular injury and monocyte infiltration, while the stable posttransplant state was notable for T-cell infiltration. CONCLUSIONS These data suggest that monocytes and transcripts related to their recruitment dominate the immediate postreperfusion state. This gives way to a T-cell dominant milieu even in grafts selected for their stable function and absence of rejection. These data have implications for understanding the fundamental link between I/R injury and alloimmunity.

Recreational music-making modulates the human stress response: a preliminary individualized gene expression strategy.

BACKGROUND: A central component of the complex human biological stress response is the modulation of the neuro-endocrine-immune system with its intricate feedback loops that support homeostatic regulation. Well-documented marked gene expression variability among human and animal subjects coupled with sample collection timing and delayed effects, as well as a host of molecular detection challenges renders the quest for deciphering the human biological stress response challenging from many perspectives. MATERIAL/METHODS: A novel Recreational Music-Making (RMM) program was used in combination with a new strategy for peripheral blood gene expression analysis to assess individualized genomic stress induction signatures. The expression of 45 immune response-related genes was determined using a multiplex preamplification step prior to conventional quantitative Real Time Polymerase Chain Reaction (qRT-PCR) mRNA analysis to characterize the multidimensional biological impact of a 2-phase controlled stress induction/amelioration experimental protocol in 32 randomly assigned individuals. RESULTS: In subjects performing the RMM activity following a 1-hour stress induction protocol, 19 out of 45 markers demonstrated reversal with significant (P = 0.05) Pearson correlations in contrast to 6 out of 45 markers in the resting control group and 0 out of 45 in the ongoing stressor group. CONCLUSIONS: The resultant amelioration of stress-induced genomic expression supports the underlying premise that RMM warrants additional consideration as a rational choice within our armamentarium of stress reduction strategies. Modulation of individualized genomic stress induction signatures in peripheral blood presents a new opportunity for elucidating the dynamics of the human stress response.