Seasonal variation in peripheral blood leukocyte subsets and in serum interleukin-6, and soluble interleukin-2 and-6 receptor concentrations in normal volunteers

Abstract

This study has been carried out in order to investigate seasonal variation in peripheral blood immune cells, such as leukocytes, monocytes, neutrophils, lymphocytes, CD3+ T, CD4+ T, CD8+ T, CD25+ T, CD20+ B, and serum interleukin-6 (IL-6), soluble IL-6 receptor (sIL-6R) and sIL-2R levels in normal volunteers. Toward this end, 26 normal volunteers (13 men, 13 women) had monthly blood samplings during one calendar year for peripheral blood count, flow cytometric enumeration of peripheral leukocyte subsets and immunoassays of IL-6, sIL-6R and sIL-2R. It was found that most of the immune variables change rhythmically during the seasons as a group phenomenon. Statistically significant yearly variations with seasonal rhythms, i.e. annual rhythms or harmonics, such as semiannual, tetramensual and trimensual rhythms, were found in the number of leukocytes, neutrophils, monocytes, lymphocytes, CD4+ T, CD8+ T, CD25+ T, CD20+ B cells, in the CD4+/CD8+ ratio, and serum IL-6 and sIL-6R levels. It is concluded that the immune system is characterized by a multifrequency time-structure with significant high-amplitude yearly variations in the number of some peripheral blood leukocyte subsets.

Causes of Variation in The Neutrophil–Lymphocyte and Platelet–Lymphocyte Ratios: a Twin-Family Study

“…For both ratios, average levels were higher in colder months, indicating seasonal influences on immune parameters. This is consistent with previous work, which found higher levels of inflammation during the winter in European countries [40] and in line with previous studies on seasonal effects on cell counts in humans [14][15][16][17]. One likely explanation for the higher levels during the winter is that there is a higher prevalence of viral infections during the cold season [18], though many other factors are likely involved in the seasonal effects on immune response and further study is needed [40].…”

“…In addition to the contribution of inherent factors to variation among individuals, immune function may also be influenced by external factors. Seasonality is thought to be an important source of variation in the hematological profile [14]. Lymphocyte subset counts as well as platelet levels have been found to be lower in the summer season [15,16] and month-to-month changes in leukocyte and platelet levels were observed in a study of trained and untrained men [17].…”

Seasonality in Flares and Months of Births of Patients with Ulcerative Colitis in a Chinese Population

“…The possible factors modulating the immune response in different seasons and at different temperatures has been studied by some groups. The warmer temperature can facilitate the locomotion of human neutrophilic leukocytes and lymphoblasts [34,35] and thereby induce the release of inflammatory mediators, such as interleukin (IL)-6 [36,37]. These fluctuations in immune function in the different seasons may explain the seasonal variations in symptom flares of UC.…”

Tietze Syndrome and Idiopathic Costochondritis - Treatment Modalities, Recurrence Rates, Seasonality

“…For example, monocytes are more active during the autumn, and the mitotic activity of lymphocytes is highest in summer. [19,23,24] In our study, the diagnoses of IC and TS were lowest during the autumn-summer period. There was no difference between our groups in terms of the CRP level or erythrocyte sedimentation rate.…”