Effect of K, MG aspartate on some biological parameters of aging rats.

The effect of K and Mg salts of aspartic acid (Cardilan) on the serum concentration of selected proteins and phagocytic activity in aging male Wistar rats was investigated. Cardilan was administered in tap water for 7 days a month for 3 months before the last observed interval (12, 18 and 24 month). In a part of animals, the aging process was accelerated by sublethally gamma-irradiation. The administration of Cardilan slowed down the changes in the concentration of prealbumin, albumin, haptoglobin, haemopexin, C3 complement in non-irradiated rats (DC). This effect was extended to the changes in transferrin level in irradiated rats (IDC). The phagocytic activity in both DC, IDC rats was lower compared with controls drinking water (DW, IDW), but not significantly. The effect of Cardilan administration appears to be the greatest in 24-month-old rats, when the treated animals survived better by 25% in IDC group and by 26% better in DC rats, compared with those of the same age controls. Potassium and magnesium salts of aspartates are suitable compounds for life prolongation in the experimental conditions.

Ultraviolet B radiation exerts enhancing effects on the production of a complement component, C3, by interferon-gamma-stimulated cultured human epidermal keratinocytes, in contrast to photochemotherapy and ultraviolet A radiation that show suppressive effects.

The present study was designed to investigate by using enzyme-linked immunosorbent assay and reverse transcriptase-polymerase chain reaction methods whether photochemotherapy (PUVA) or ultraviolet (UV) B treatment affects C3 production by interferon (IFN)-gamma-stimulated keratinocytes cultured in serum-free medium. The results showed that PUVA and UVA reduced C3 production by IFN-gamma-stimulated epidermal keratinocytes dose-dependently, although the effect of PUVA was stronger than that of UVA alone. Interestingly, UVB induced an enhancement of C3 production at doses ranging from 10 to 50 mJ cm-2. This phenomenon was found at both the protein and mRNA levels. In every experiment, changes in C3 mRNA levels preceded those in its protein levels. Reduced C3 production at higher doses of 75 and 100 mJ cm-2 were probably due to cytotoxic effects of UVB. In our experimental system, PUVA, UVA or UVB treatment did not affect C3 production without IFN-gamma stimulation. Our results suggest that a reduction in C3 production by PUVA treatment may in part explain the efficacy of PUVA in the treatment of inflammatory dermatoses such as psoriasis, while the results of the UVB experiments may partially explain the proinflammatory nature of UVB.

Early detection of epidermal dust-like particles in experimentally UV-induced lesions in patients with photosensitivity and lupus erythematosus.

Dust-like particles, producing a specific fine-speckled, epidermo-subepidermal direct immunofluorescence staining pattern, have been associated mainly with subacute cutaneous lupus erythematosus (LE). Under experimental conditions the appearance of immunoglobulins along the basement membrane in ultraviolet (UV) light-induced lesions has been reported as a late phenomenon. In this study, photoprovocations with UVA and UVB light were carried out in 16 photosensitive patients with discoid (n = 13), subacute cutaneous (n = 2) or systemic LE (n = 1) and serial biopsies from UV-induced lesions were processed for direct immunofluorescence. A specific, fine-speckled epidermal staining was detected within 7 to 14 days after UV provocation in 7/16 of the patients; in the majority of those patients associated with anti-SSA antibodies adn discoid LE without systemic manifestations of their disease.

Travel to sunny countries is associated with changes in immunological parameters.

Under laboratory conditions, various studies have shown that changes in immunological parameters must be expected after exposure to ultraviolet (UV) light. The objective of the present study was to evaluate, whether such changes can also be revealed after a vacation to a sunny country without prior adaptation to ultraviolet radiation. In 32 volunteers white blood cells, lymphocyte subpopulations, sIL2-R, sCD14, immunoglobulins and complement factor C3 were determined before and after a vacation in a country with abundant sunshine during winter. The subjects received relevant doses of UVB as confirmed by questionnaires, UVB-dosimetry and the significant increase of 25-hydroxyvitamin D. After vacation, there was a significant decrease of the CD4/8 ratio and the serum concentration of IgG. The serum concentration of sIL2-R, sCD14, IgA and C3 was increased after the journey. Sunshine exposure without prior adaptation may be responsible for significant alterations in the immune system in association with a vacation during winter.

The effects of radiotherapy on the immune system of patients with nasopharyngeal carcinoma.

We report on 123 patients with nasopharyngeal carcinoma whose immune status was measured at the time of diagnosis, the day radiotherapy was completed, and then 2-3 months and 6-8 months after completion of radiotherapy. Immunological tests performed included the lymphocyte transformation test, the erythrocyte-rosette formation test (ERFT), the 29 degrees C erythrocyte-rosette formation test (29 degrees C ERFT), lymphocyte counts (lymphocytes/mm3 and percentage of lymphocytes), levels of serum immunoglobulins (IgG, IgA, IgM), complement (C3) and circulating immune complexes (CIC), the antinuclear antibody test and a skin test using phytohaemagglutinin (PHA). There were statistically significant differences in all tests (except C3) between patients and normal controls. Marked differences were seen in the lymphocyte count, ERFT, and 29 degrees C ERFT after radiotherapy (p less than 0.01). The diameters of induration of the PHA skin tests were less than those before radiotherapy (p less than 0.01). There were higher incidences of recurrence and metastases in the patients with high levels of CIC and low numbers of lymphocytes in the peripheral blood after radiotherapy. Cellular immunity remained at a low level 8 months after radiotherapy.

Effect of irradiation and depletion of C3-complement component on the course of Treponema pallidum infection in a resistant guinea pig strain.

The role of complement and ionizing radiation in the natural resistance to Treponema pallidum infection of Albany guinea pigs was explored. Depletion of C3 by cobra venom factor for a period of 14 days affected neither the host's susceptibility to infection nor the humoral response. Total body irradiation with 420 or 800 R was fatal within 20-30 days and there was no multiplication of treponemes in the infected host. Animals showing lethal signs were euthanized and tissues removed for examination. Exposure to a nonlethal dose of 300 R increased the susceptibility to infection (46% symptomatic lesions) and facilitated multiplication of treponemes at the site of inoculation and in the lymphoid organs, but the humoral response was not different from that of non-irradiated controls. The results seem to suggest a defect in antigen recognition by the immunocompetent cells in the resistant Albany guinea pigs.

Photodynamic action of uroporphyrin on the complement system in porphyria cutanea tarda.

We investigated the effect of UV light (320-460 nm) on total hemolytic CH50 activity and C3 cleavage in sera obtained from 14 patients with porphyria cutanea tarda. Irradiation with 5, 10, or 50 J/cm2 resulted in a 12%-60% loss of CH50 and a 5%-30% cleavage of native C3 as estimated by planimetric evaluation of the immunoelectrophoretic C3 pattern. The complement changes were most pronounced in sera from patients with active disease and were minimal or absent in patients who were in remission. In all cases, the decrease of CH50 and C3 cleavage was proportional to the plasma-porphyrin concentration and the dose of radiation. After exposure to 320- to 460-nm light, similar changes were seen in normal human serum (NHS) to which exogenous uroporphyrin had been added. Beta-carotene and chloroquine had no inhibitory effect on the photodynamic complement activation. The C3 cleavage in irradiated NHS containing uroporphyrin was not affected by 10 mM EGTA, but was partially inhibited in the presence of 30 mM EDTA, thus indicating that the interaction of photoexcited uroporphyrin with the complement system differs from classical-pathway complement activation.