Systemic suppression of human peripheral blood phagocytic leukocytes after whole-body UVB irradiation

Abstract

We examined systemic effects of wholebody UVB irradiation on human peripheral blood phagocytes. We found that 24 h after a single erythemal dose of UVB radiation two phagocyte functions, adhesion and phagocytosis, were reduced by 50%. This functional suppression was accompanied by a significant decrease in the expression of complement receptors (CR1 and CR3) and IgG Fc receptors (FcRII and FcRIII). The greatest reduction (47%) was observed in CR3, which is important for both adhesion and phagocytosis. A kinetic analysis showed that both CR1 and CR3 levels started to decrease 15 min after the UVB exposure, reaching the lowest levels at 4.5-and 24-h time points, respectively. The down-modulation of CRs after whole-body UVB exposure was not due to a defective receptor synthesis or translocation from internal stores to plasma membrane because the maximal CR levels in stimulated cells were not affected by UVB. No change in the serum soluble ICAM-1 was detected after UVB, which rules out CD11b epitope masking by sICAM-1. UVB did not release low-receptor-density myeloid progenitor cells from storage pools into circulation. Interleukin 10, a mediator of UVB-induced immunosuppression, was unable to modulate CR expression in vitro. When seven suberythemal whole-body UVB exposures were given repeatedly within 2 weeks, a significant decrease in CR expression was seen, which was greatest after three irradiations. Our data suggest that an exposure to UVB has systemic effects in humans which, possibly due to the down-modulation of preexisting cell-surface receptors, suppress some important functions of circulating phagocytic cells. J. Leukoc. Biol. 65: 573-582; 1999.

Decreased Neutrophil Skin Infiltration After UVB Exposure in Patients with Polymorphous Light Eruption

“…Since four of six healthy controls and three of five PLE patients showed the presence of neutrophils in the epidermis 18 h after irradiation (data not shown), however, we hypothesize that once in the tissue, the migration capacity of the neutrophils is similar in PLE patients and healthy controls. Leino et al (1999) showed reduction in the phagocytosis and adhesive function of leukocytes in healthy human volunteers after whole-body irradiation with UVB, possibly due to downregulation of cellsurface receptors. Furthermore, de la Fuente et al (2001) showed both decreased phagocytosis and IL-8 induced chemotaxis in polymorphonuclear cells of patients with systemic lupus erythematosus (SLE).…”

Ultraviolet B Radiation Induces a Transient Appearance of IL-4+ Neutrophils, Which Support the Development of Th2 Responses

“…Basophils and eosinophils also have a multilobed nucleus and express CD11b and CD15, but they are not known to infiltrate UVB-exposed normal human skin (24), and by means of specific mAbs we demonstrated that these two cell types are absent in irradiated skin. It has been reported that UVB radiation can cause a considerable decrease in the expression of CD11b on neutrophils isolated from peripheral blood (25). Nevertheless, this marker is clearly detectable on infiltrating neutrophils in UVB-treated skin, as demonstrated by immunohistochemistry.…”

Impact of UV-B radiation on the digestive enzymes and immune system of larvae of Indian major carpCatla catla

“…Similarly, UV-B radiation also suppressed the immunity of the roach (Rutilus rutilus) in terms of suppressed macrophage migration and respiratory burst activities, indicating that UV-B has the potency to suppress the functioning of phagocytes (Salo et al 1998). Systemic effects of whole-body UV-B irradiation on human peripheral blood phagocytes was studied and it was found that 24 h after a single dose of UV-B radiation, two phagocytic functions, i.e., adhesion and phagocytosis were reduced by 50% (Leino et al 1999). The effects of short-term exposure to UV-B radiation on lymphocyte-related parameters were studied under controlled laboratory conditions using roach (Rutilus rutilus), a cyprinid teleost, as the model fish.…”