Effect of continuous darkness on immune response [in vivo assay]

Reports denote that changes in day length enhance or suppress components of immune function in several mammalian species. The aim of the present experimental study is directed to test the hypothesis dealing with the effect of photoperiods on some immune limbs responsiveness. Twenty six male and female BALB/C mice, 5-7 weeks old, 14-18gm weight divided into two groups, test groups [n=8 mice for each sex] and control groups [n =5 for each sex]. Test groups were kept in a dark room for a month, while control groups were kept in a room where the photoperiod was day light: darkness 12:12hr. All studied groups immunized with 0.2ml [10% sheep red blood cells] on day 4 and 8 of the last 12 days of the experiment. The weights of all animals were measured at the beginning and the end of the experiment. Arthus reaction, delayed type hypersensitivity and serum antibody titer were assessed on day 11 and 12 of program. Significant increase [P<0.005] in body weight, index level of Arthus reaction, delayed type hypersensitivity and serum antibody titer in the test groups in comparison with the control groups were found. Data are consistent with the hypothesis that immune parameters are enhanced in short photoperiods or continuous darkness

Activation of complements pathways in patients with Bechcet's disease

Behcet's disease [BD] is amultisystemic inflammatory disorder, onset is belived to be triggered by many factors with a particular immunogenetic Factor. The aim of this study is elucidate the role of C3,C4 complement components With CH50 and HLA typing as immunogenetic factor in aetiopathogenesis of this disease. Seventy patients with Behcet's disease have been studied to assess the level of serum complement's components [C3,C4], complement total hemolytic activity [CH50], and HLA- typing using single radial immunodifusion [SRID], titration assay, and microlymphocytotoxicity methods respectively, compared with age, sex and ethic matched 30 patients control with recurred oral ulcer, 25 healthy relative, and 30 healthy volunteer. Significant elevation [P<0.01,0.05,0.0005] in C3, C4 and CH50 levels was clearly observed in patients with BD, especially those who show to be HLA-B51[5] positive in comparison to control groups. Increased level ofCH50 which is reflected the total activity of the classical and lytic pathways, elevation of C3 level is an index of the disease activities which support that alternative pathway play a role in the pathogenesis of BD in Iraqi patients especially in those with HAL - B51[5] positive