Natural killer cells in dilated cardiomyopathy.

Increased Level of HLA-DR-Expressing T Lymphocytes in Peripheral Blood from Patients with Idiopathic Dilated Cardiomyopathy

“…The presence in the peripheral blood of activated lymphocytes has also been noted in patients with autoim mune disorders [18][19][20]. Thus, our findings support earlier reports suggesting that au toimmune mechanisms might be important in the pathogenesis of IDC [10][11][12][13].…”

“…Additionally, in some patients the natural killer cell system might be involved in the pathogenesis of the disease [ 13],…”

“…The disease probably represents the advanced stage of myocardial damage from a variety of causes [4], One possible explanation for this myocyte de struction is that the immune system through cytotoxic T lymphocytes or heart muscle an tibodies destroys the myocardial cells. Thus, it has been proposed that viral myocarditis can progress to IDC as a consequence of a perpetuating autoimmune reaction [5][6][7], In support of this assumption is the finding of Coxsackie B virus specific RNA sequences and infiltrating lymphocytes among dam aged myocytes in heart muscle biopsy speci mens from some IDC patients [6][7][8][9], Other disturbances in the immune system have also been reported in IDC patients [10][11][12][13].…”

Tumor Necrosis Factor, Natural Killer Activity and Other Measures of Immune Function and Inflammation in Elderly Men with Heart Failure

“…Chronic heart failure (CHF) is a disabling disease affecting 2.5 mil lion people a year in the United States, with an overall 5-year mortality of approximately 50% [1,2], Many organ systems are in fluenced by and play a role in the etiology of CHF [3]. The immune system is among these, though its role has not been fully de fined [3], The heart has clearly been shown to be a target organ of immune injury [4][5][6][7], Increased antibodies, immunoglobins, and complement are found in rheumatic heart disease, viral cardiomyopathy, Lyme carditis, SLE, and sarcoid [4], The role of inflamma tion and immune injury in atherosclerosis has been a topic of increasing interest [8]. An association between heart failure and re duced T-lymphocyte suppressor function has recently been documented [9], Reduced natu ral killer (NK) cell cytotoxicity [7,10], dimin ished lymphocyte responsiveness to mitogens [11] and altered T-cell suppressor activity [12] have all been observed in patients with idiopathic dilated cardiomyopathy.…”

“…The immune system is among these, though its role has not been fully de fined [3], The heart has clearly been shown to be a target organ of immune injury [4][5][6][7], Increased antibodies, immunoglobins, and complement are found in rheumatic heart disease, viral cardiomyopathy, Lyme carditis, SLE, and sarcoid [4], The role of inflamma tion and immune injury in atherosclerosis has been a topic of increasing interest [8]. An association between heart failure and re duced T-lymphocyte suppressor function has recently been documented [9], Reduced natu ral killer (NK) cell cytotoxicity [7,10], dimin ished lymphocyte responsiveness to mitogens [11] and altered T-cell suppressor activity [12] have all been observed in patients with idiopathic dilated cardiomyopathy. An 'im mune hypothesis' for the pathogenesis of di lated cardiomyopathy has been suggested [4], which proposes the following sequence of events: viral infection with resultant T-lym phocyte system activation, lymphocyte infil tration of the myocardium, subsequent myo cyte necrosis, and ultimately progression to heart failure.…”