The Journal of Immunology, 1999, 163: 533-534.
Copyright © 1999 by The American Association of Immunologists
Increased Apoptosis in Patients with Major Depression: A Preliminary Study
Eran Eilat
,
Shlomo Mendlovic1,*,
Adiel Doron*,
Vera Zakuth
and
Zvi Spirer
*
"Shalvata" Mental Health Center, Hod Hasharon, Israel; and
The Leon-Alkalai Chair in Pediatric Immunology, Sackler School of Medicine, and the Danas Children Hospital, Tel-Aviv, Israel.
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Abstract
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Apoptosis is a programmed cell death that can be observed in normal
cells. Major depression poses a combination of a depressed and
destructive autoimmune reaction. We measured apoptosis in the PBLs of
seven patients with major depression and in age- and sex-matched
controls. We observed significantly increased apoptosis in the PBLs of
depressive patients (p < 0.05). These preliminary
results could contribute to an understanding of the interactions of the
CNS with the immune system, which could lead to the increased
vulnerability of the CNS in depressive disorders. Further studies are
needed to establish these results.
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Introduction
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Apoptosis
is a normal physiological programmed cell death that can be enhanced by
a variety of external stimuli, such as viral infections, medications
(i.e., anticancer treatments), and pathological conditions (e.g.,
autoimmune diseases and degenerative diseases of the CNS)
(1). This phenomenon can be mediated via various pathways
that cause condensation of the cytoplasm and chromatin, nuclear
fragmentation, and ultimate sequestration of cellular contents into
membrane-bound apoptotic bodies (2). Major depression is a
common disorder, with a lifetime prevalence of
15%. Moreover, it
may be a life threatening condition, as 30% of all depressive patients
attempt suicide and 10% eventually commit suicide (3).
Major depression has been shown to be associated with various immune
abnormalities, although the findings have not been consistently
demonstrated (4).
We hypothesized previously that depressive patients can exploit their
immune system for suicide (5), and one of the possible
mechanisms includes apoptosis. Therefore, we measured the apoptotic
cells in PBLs of depressive patients and normal age- and sex-matched
controls.
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Materials and Methods
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Patients
Of >500 patients referred to the psychiatric facilities
affiliated with the Shalvata Mental Health Center, nine patients (six
males and three females; age 51.7 ± 12) and nine age- and
sex-matched controls (age 50.8 ± 15) entered the study. Two
couples were excluded due to prolonged delay in blood delivery. The
inclusion criterion was major depression (diagnosed according to DSM-IV
(Diagnostic and Statistical Manual) criteria) that lasted 212 wk. The
exclusion criteria were age younger than 18 years; any other major
psychiatric disorder (e.g., schizophrenia, substance abuse, and
reactive depression); medication by antidepressive, antipsychotic, or
anxiolytic drugs; usage of immune-affecting medications; any
immunological or hematological disorder; and an infective disease
(localized or generalized) in the month before examination. These
stringent exclusion criteria were applied because antidepressive and
anxiolytic medications are known to alter various immune functions
(6, 7). The controls were randomly selected from a pool of
healthy persons who agreed to participate in the study. Matching was
done by sex and age criteria.
After a full explanation and informed consent, depression, anxiety, and
suicidal tendency were assessed by the Hamilton Depression Rating
Scale, Hamilton Anxiety Rating Scale, and Beck Depression Inventory
questionnaires, respectively.
Peripheral blood (25 ml) was drawn via venous puncture. Blood was
transported and analyzed within 2 h. Apoptosis was assessed by
flow cytometry using Apoptest (Ylem, Avezzano, Italy), which is based
on the increased stainability of lymphoid cells on the part of newly
developed fluorophores that occur during the early phases of apoptosis,
as described previously (8). In brief, whole blood was
lysed within <2 h; cells were stained for Apostain, fixed (with 4%
paraformaldehyde), and evaluated in a FACScan flow cytometer (Becton
Dickinson, Mountain View, CA) with excitation at 650 nm (FL3 channel).
Cells were gated on lymphocytes and evaluated as a percentage of whole
cells.
Statistical analysis
For statistical evaluation of the apoptotic cells in depressive
patients and healthy controls, we used Wilcoxons signed-rank
test.
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Results
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Table I
demonstrates depression and
anxiety scores and the apoptotic cells as a percentage of whole PBLs in
depressive patients and their matched controls. The depressed patients
had a significantly higher Hamilton depression rating score (25.85
± 6.4) compared with the controls (0.4 ± 0.7). Similar findings
were seen for the Hamilton anxiety rating scale (29.85 ± 7.1 in
depressive patients vs 1 ± 1.9 in controls). In Fig. 1
, we demonstrate the percentage of
apoptotic cells in depressive patients and their matched controls; a
significant increase in apoptosis was observed in the depressive
patients (p < 0.05).
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Discussion
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In patients with major depression, various immunological
abnormalities were observed, such as reduced NK cell activity (9, 10, 11) and decreased T cell function (12). In the
present study, we observed an increased tendency for apoptosis of PBLs.
We observed a wide range of apoptosis in the normal controls and in the
depressed patients as well. This wide range could be attributed to the
time gap between the blood drawn from subjects and the fixation, the
transportation of blood, or the sensitivity of the assay. However, it
should be emphasized that the blood from patients and their matched
controls was preformed almost simultaneously, and both samples were
transported together. In five of the depressed patients (71.5%), the
percentage of apoptosis was higher than in the matched controls. In one
patient (14.25%), the percentage of apoptosis was even, and in one
other patient (14.25%), the percentage of apoptosis was lower than
that seen for the matched control.
Several other studies support immune activation in acute depression.
Maes et al. (13, 14) showed that depression is associated
with increased lymphokine production, high levels of acute phase
proteins, and a shift in the Th to T suppressor ratio, which all
suggest activation of the immune system. Furthermore, few studies
demonstrated self-directed activation of the immune system (15, 16). Our results can explain findings obtained by others that
showed reduced NK activity and lower mitogen stimulation in depressed
patients (10, 17, 18). Some of these observations can be
attributed to the increased apoptosis in these cells.
This pattern may suggest a "suicidal" tendency of the immune system
in depressed patients and could lead to a vulnerability of the immune
system, with decreased ability to resist infections, tumors, or
autoimmune diseases. To our knowledge, this study is the first to
demonstrate increased apoptotic activity in the PBLs of depressive
patients. It is not yet clear whether this tendency could be attributed
to a certain subpopulation of the PBLs or to the PBLs in general. Our
study used highly selective criteria; despite the small number of
patients in this study, the results were significant.
In conclusion, we presented preliminary data that showed an increased
apoptosis in the PBLs of patients with major depression compared with
controls; these data may be attributable to the interactions of the CNS
and the immune system. Further studies should be conducted to establish
this preliminary study.
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Footnotes
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1 Address correspondence and reprint requests to Dr. Shlomo Mendlovic, "Shalvata" Mental Health Center, POB 94, Hod Hasharon, Israel. E-mail address: 
Received for publication April 16, 1999.
Accepted for publication April 26, 1999.
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References
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-
Carson, D. A., J. M. Ribereiro. 1993. Apoptosis and disease. Lancet 341:1251.[Medline]
-
Kerr, J. F. R., C. M. Winterford, B. V. Harmon. 1994. Apoptosis: its significance in cancer and cancer chemotherapy. Cancer 73:2013.[Medline]
-
Beskow, J.. 1990. Depression and suicide. Pharmacopsychiatry 23:3.[Medline]
-
Herbert, T. B., S. Cohen. 1993. Depression and immunity: a meta-analytic review. Psychol. Bull. 113:472.[Medline]
-
Mendelovic, S., A. Doron, E. Eilat. 1997. Can depressive patients exploit the immune system for suicide?. Med Hypotheses 49:445.[Medline]
-
Uzunova, V., Y. Sheline, J. M. Davis, A. Rasmusson, D. P. Uzunov, E. Costa, A. Guidotti. 1998. Increase in the cerebrospinal fluid content of neurosteroids in patients with unipolar major depression who are receiving fluoxetine or fluvoxamine. Proc. Natl. Acad. Sci. USA 95:3239.[Abstract/Free Full Text]
-
De La Rocque, L., M. M. Campos, B. Olej, F. Castilho, I. F. Mediano, V. M. Rumjanek. 1995. Inhibition of human LAK-cell activity by the anti-depressant trifluoperazine. Immunopharmacology 29:1.[Medline]
-
Ferlini, C., A. Kunkl, G. Scambia, A. Fattorossi. 1997. The use of Apostain in identifying early apoptosis. J. Immunol. Methods 203:95.
-
Bauer, M. E., G. J. Gauer, C. Luz, R. O. Silveira, N. B. Nardi, C. A. von Muhlen. 1995. Evaluation of immune parameters in depressed patients. Life Sci. 57:665.[Medline]
-
Caldwell, C. L., M. Irwin, J. Lohr. 1991. Reduced natural killer cell cytotoxicity in depression but not schizophrenia. Biol. Psychiatry 30:1131.[Medline]
-
Schleifer, S. J., S. E. Keller, J. A. Bartlett, H. M. Eckholdt, B. R. Delaney. 1996. Immunity in young adults with major depressive disorder. Am. J. Psychiatry 153:477.[Abstract/Free Full Text]
-
Anesi, A., D. Franciotta, E. Di-Paolo, E. Zardini, G. V. Melzi-dEril, F. Zerbi. 1994. PHA-stimulated cellular immune function and T-lymphocyte subsets in major depression disorders. Funct. Neurol. 9:17.[Medline]
-
Maes, M.. 1995. Evidence for an immune response in major depression: a review and hypothesis. Prog. Neuro-psychopharmacol. Biol. Psychiatry 19:11.[Medline]
-
Maes, M., S. Scharpe, H. Y. Meltzer, E. Bosmans, E. Suy, J. Calabrese, P. Cosyns. 1993. Relationship between interleukin-6 activity, acute phase proteins, and function of the hypothalamic-pituitary-adrenal axis in severe depression. Psychiatry Res. 49:11.[Medline]
-
Haggerty, J. J., S. G. Silva, M. Marquardt, G. A. Mason, H. Y. Chang, D. L. Evans, R. N. Golden, C. Pedersen. 1997. Prevalence of antithyroid Abs in mood disorders. Depress. Anxiety 5:91.[Medline]
-
Maes, M., E. Bosmans, E. Suy, C. Vandervorst, C. Dejonckheere, J. Raus. 1991. Antiphospholipid, antinuclear, Epstein-Barr, and cytomegalovirus Abs, and soluble interleukin-2 receptors in depressive patients. J. Affect. Disord. 21:133.[Medline]
-
Zisook, S., S. R. Shuchter, M. Irwin, D. F. Darko, P. Sledge, K. Resovsky. 1994. Bereavement, depression, and immune function. Psychiatry Res. 52:1.[Medline]
-
Irwin, M., U. Lacher, C. Caidwell. 1992. Depression and reduced natural killer cytotoxicity: a longitudinal study of depressed patients and control subjects. Psychol. Med. 22:1045.[Medline]
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