![]() ![]() |
|
|
|---|---|---|
|
|
5: Activation-induced T-cell death and immune dysfunction after implantation of left-ventricular assist device. Ankersmit HJ, Tugulea S, Spanier T, Weinberg AD, Artrip JH, Burke EM, Flannery M, Mancini D, Rose EA, Edwards NM, Oz MC, Itescu S; Lancet 1999 Aug 14;354(9178):550-5. Pubmed Link BACKGROUND: Cardiac transplantation is a
limited option for end-stage heart failure because of the shortage of
donor organs. Left-ventricular assist devices (LVADs) are currently under
investigation as permanent therapy for end-stage heart failure, but
long-term successful device implantation is limited because of a high rate
of serious infections. To examine the relation between LVAD-related
infection and host immunity, we investigated immune responses in LVAD
recipients. METHODS: We compared the rate of candidal infection in 78
patients with New York Heart Association class IV heart failure who
received either an LVAD (n=40) or medical management (controls, n=38).
Fluorochrome-labelled monoclonal antibodies were used in analyses of
T-cell phenotype. Analysis of T-cell function included intradermal
responses to recall antigens and proliferative responses after stimulation
by phytohaemagglutinin, monoclonal antibodies to CD3, and mixed lymphocyte
culture. We measured T-cell apoptosis in vivo by annexin V binding, and
confirmed the result by assessment of DNA fragmentation.
Activation-induced T-cell death was measured after T-cell stimulation with
antibodies to CD3. All immunological tests were done at least 1 month
after LVAD implantation. Between-group comparisons were by Kaplan-Meier
actuarial analysis and Student's t test. FINDINGS: By 3 months after
implantation of LVAD, the risk of developing candidal infection was 28% in
LVAD recipients, compared with 3% in controls (p=0.003). LVAD recipients
had cutaneous anergy to recall antigens and lower (<70%) T-cell
proliferative responses than controls after activation via the T-cell
receptor complex (p<0.001). T cells from LVAD recipients had higher
surface expression of CD95 (Fas) (p<0.001) and a higher rate of
spontaneous apoptosis (p<0.001) than controls. Moreover, after
stimulation with antibodies to CD3, CD4 T-cell death increased by 3.2-fold
in LVAD recipients compared with only 1.2-fold in controls (p<0.05).
INTERPRETATION: LVAD implantation results in an aberrant state of T-cell
activation, heightened susceptibility of CD4 T cells to activation-induced
cell death, progressive defects in cellular immunity, and increased risk
of opportunistic infection. a PDF of this paper can be provided upon request |