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B.H. Natelson, Q. Zhang, X.-D. Zhou, T. Denny,
J.E. Ottenweller, and W.C. Gause.
Center for Environmental Hazards Research, VAMC, E. Orange
and
CFS Center, NJ Medical School, Newark
One of the hypotheses for the genesis of chronic fatigue
syndrome (CFS) is a dysregulated immune system. The purpose of this study
was to evaluate that hypothesis by comparing immunological parameters
of Gulf veterans (n = 43) and civilians (n = 68) who fulfilled published
case definitions for CFS to their respective healthy controls: 34 Gulf
veterans and 53 civilians. Dependent variables included cell sorter based
white blood cell counts (total WBC, total lymphocytes, NK cells, total
B cells, total T cells, CD4+ T cells, CD8+ T cells, and the following
activation markers: CD4+CD45R0+, CD4+CD45RA+, CD8+CD11b-, CD8+CD38+, CD8+HLA-DR+,
and CD8+CD28+) as well as IL-2, IL-4, IL-6, IL-10, IL-12, IFN-?, and TNF-a
assayed by RT-PCR. Statistical analysis was performed using multivariate
mixed effects models. No differences in any variable were found for the
civilian group. In contrast, statistically significant differences were
found in a number of immunological variables between Gulf vets with CFS
and healthy Gulf vet controls. Specifically, Gulf vets with CFS had higher
numbers of total T cells and of T helper cells than both Gulf and civilian
healthy controls. Furthermore, Gulf vets with CFS had higher percentages
of total T cells and of T helper cells and a lower percentage of NK cells
than Gulf vet controls (these were not different from healthy civilians).
However, cell surface marker data in CFS vets never fell outside the laboratory's
normative nonveteran range. In addition, CFS vets had higher levels of
IL-2, IL-10, IFN-?, and TNF-a than vet controls. The data provide no support
for the immune dysfunction hypothesis in the civilian CFS group, but do
so for the Gulf veteran CFS group. A critical question is the meaning
of these results. Concerning each of the cell surface markers evaluated,
veterans had substantially less variability than civilians. This suggests
that veterans were more immunologically homogenous than civilians -- allowing
differences to be detected. One interpretation of the immunological differences
exhibited by CFS Gulf vets is that immune dysregulation plays a role in
the genesis of this apparent epidemic presentation of CFS. However, differences
between the veteran groups in terms of sleep, chronic stress, and level
of activity also could contribute to produce the apparent differences.
KEYWORDS: Immune Dysregulation, Cell Surface Marker,
Cytokines
This research was supported by the Department of Veteran
Affairs through the New Jersey Center for Environmental Hazards Research |
