Effects of purified perforin and granzyme A from cytotoxic T lymphocytes on guinea pig ventricular myocytes

Autor: John Ding-E Young, Bella Felzen, Ofer Binah, Dalia Rosen, Gideon Berke, Reymond Coleman, Jurg Tschopp
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Pore Forming Cytotoxic Proteins
Physiology
Voltage clamp
Heart Ventricles
Guinea Pigs
Action Potentials
chemical and pharmacologic phenomena
Granzymes
Ion Channels
Membrane Potentials
Physiology (medical)
Cytotoxic T cell
Myocyte
Animals
Ventricular Function
Action Potentials/drug effects Animals Calcium/pharmacology Cells
Cultured Granzymes Guinea Pigs Heart Ventricles/cytology/*drug effects/physiology Ion Channels/drug effects Membrane Glycoproteins/*pharmacology Membrane Potentials/drug effects Pore Forming Cytotoxic Proteins Serine Endopeptidases/*pharmacology *T-Lymphocytes
Cytotoxic
Cells
Cultured
Membrane Glycoproteins
biology
Perforin
Serine Endopeptidases
hemic and immune systems
Resting potential
Cell biology
CTL
Granzyme
Immunology
biology.protein
Granzyme A
Calcium
Cardiology and Cardiovascular Medicine
T-Lymphocytes
Cytotoxic
Zdroj: Cardiovascular Research, vol. 28, no. 5, pp. 643-9
Popis: Objective: Involvement of cytotoxic T lymphocytes (CTL) in heart transplant rejection as well as in viral myocarditis is well established, but the precise mechanisms whereby infiltrating CTL damage the myocardium are unknown. The aim of the study was to investigate how CTL derived perforin, the serine protease granzyme A, and the combination of both, damage guinea pig ventricular myocytes. Methods: Action potentials and membrane currents were recorded by means of the whole cell configuration from guinea pig ventricular myocytes. Results: Resembling the effects of CTL derived lytic granules, perforin caused gradual myocyte shortening and contracture, leading to complete loss of the rod shaped morphology and to cell destruction. These changes were preceded by shortening of action potential duration and reduction of resting potential and action potential amplitude, followed by complete inexcitability. Granzyme A alone was ineffective, but accelerated the deleterious effects of perforin on the morphological and electrophysiological properties of myocytes. The effects of perforin were further evaluated by measuring membrane currents by means of the whole cell voltage clamp. Perforin induced discrete changes in membrane current, reminiscent of single ion channels, with large conductance and open time of up to several seconds. Linear regression analysis of the channel I-V relations resulted in a conductance of 890 pS and a reversal potential of −7.6 mV. These results suggest that perforin induces large non-selective channels, which can account for most of the observed adverse effects. Conclusions: As CTL participate in the immunological rejection of the transplanted heart, it is conceivable, but remains to be shown, that part of this damage is inflicted by perforin containing lytic granules. Cardiovascular Research 1994; 28 :643-649
Databáze: OpenAIRE
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