Document 0034
 DOCN  M9480034
 TI    Circannual variation in lymphocyte subsets, revisited.
 DT    9410
 AU    Paglieroni TG; Holland PV; Sacramento Medical Foundation Center for
       Blood Research,; California.
 SO    Transfusion. 1994 Jun;34(6):512-6. Unique Identifier : AIDSLINE
       MED/94295067
 AB    BACKGROUND: Circadian and circannual variations in lymphocyte subsets,
       especially CD8+ T-lymphocytes, have been reported. This study focuses on
       CD4+ T-lymphocyte seasonal variation over a 6-year 8-month period. STUDY
       DESIGN AND METHODS: Lymphocyte subsets were quantitated monthly for four
       healthy individuals from 1986 through 1992 as part of a flow cytometry
       quality-control program. RESULTS: In general, there were no significant
       seasonal changes in the total number of white cells or in total
       lymphocyte counts. The absolute numbers of CD4+ T-lymphocytes were
       lowest in summer when the CD8+ T-lymphocytes were highest. Mean CD4+
       T-lymphocyte counts were 846, 967, 618, and 695 per microL for Subjects
       1 through 4, respectively, in winter and 432, 670, 355, and 766 per
       microL, respectively, in summer. Two healthy subjects had CD4+
       T-lymphocyte counts lower than 300 per microL on one or more occasions
       during the study period. In three of the four subjects, the percentage
       of B-lymphocytes in winter was almost double that in summer. In one of
       the four subjects, no circannual rhythm was observed in these lymphocyte
       subpopulations. CONCLUSION: The seasonal variation in CD4+ T-lymphocyte
       counts demonstrated in three healthy individuals over almost 7 years is
       again of interest in light of renewed consideration of using surrogate
       tests, such as CD4+ T-lymphocyte counts, to screen for AIDS-like
       diseases that may be in the blood supply.
 DE    Adult  Antigens, CD8/ANALYSIS  *Biological Clocks  Comparative Study
       Female  Human  Leukocyte Count  *Lymphocyte Subsets  Male  Middle Age
       Seasons  T-Lymphocytes/IMMUNOLOGY  T4 Lymphocytes  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).