الفهرس 
Introduction and aim of the workOnly 14 pages are availabe for public view
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Abstract
Apoptosis of mature T lymphocytes is involved in preserving tolerance to self-antigens and in preventing autoimmune disease initiation. However apoptosis has a potentially paradoxical role in SLE. Thus defects in inducing apoptosis of autoreactive T lymphocytes could promote autoimmunity. In contrast, the generation of nucleosomes as a result of apoptosis could induce responses to nuclear antigens, a characteristic immunological feature of SLE. Synovial proliferation, a key element in the pathology of RA is limited, and spontaneous arrest of the growth of synovial hypertrophy is occasionally observed during the course of the disease (Feigenbaum et al, 1979). The mechanism of this phenomenon is not clear, but on initial “spontaneous remission” may be followed by an intractable proliferation of the synovium, which leads to bone destruction. Of particular interest is the spontaneous withdrawal of proliferating synovial tissue, strongly suggesting the presence of apoptosis (Nishioka et al, 1998). ) is a member of a growing family of peptideTumour necrosis factor-alpha (TNF mediators comprising at least 19 cytokines (Bazzoni and Beutler, 1996), which ), Fas ligand (FasL), nerve growth factor (NGF),, LT (lymphotoxin include TNF and CD40 ligand (CD40L). With the sequencing of the human genome, additional have been identified and canproteins that share structural homology with TNF now be classified as members of a much larger TNF superfamily. Other members include peptides such as APRIL (a proliferation inducing ligand), TRAIL (TNF-related apoptosis inducing ligand), TWEAK (TNF-like and weak inducer of apoptosis), BLyS (B-lymphocyte stimulator), BAFF (B-cell activating factor Bbelonging to the TNF family) and RANK ligand (receptor activator of NF- ligand). (Dinarello and Moldawer, 2000). In this thesis, the propensity of T (CD4+, CD8+, CD45RA+, CD45RO+) lymphocytes from SLE patients, RA patients and )-induced apoptosishealth controls to undergo tumour necrosis factor alpha (TNF have been investigated. The effect of medication of lupus patients on -induced apoptosis have been studied, and performed both cross-sectional andTNF longitudinal analyses to explore links between disease activity and apoptosis. Finally, a trial to connect some of the clinical and laboratory data of patients -induced apoptosis in CD4+ and CD8+ Twith SLE and RA with the degree of TNF lymphocytes have been attempted. This study comprised 43 patients with SLE (classified according to the ACR criteria), 43 patients with RA (classified according to the ACR criteria) and 43 normal controls. All patients were subjected to: 1-Carefull history taking using the BILAG assessment score for the patients with SLE and with particular attention to the severity of pain and duration of morning stiffness for the patients with RA. 2-Clinical examination: a- General and local examination of the chest, heart, abdomen and central nervous system (CNS). b- Examination of the locomotor system which included: • The overlying skin for redness, hotness or tenderness. • Presence or absence of deformity. • Presence or absence of muscle wasting. The British Isles Lupus Assessment Group (BILAG) score was used to assess SLE disease activity globally and in each afflicted organ. The BILAG assessment divides into eight systems, or organs affected; there are 5 categories of activity A, B, C, D, and E. “A” denotes severely active disease, which requires a disease modifying drugs (more than 20 mg/day prednisolone or immunosuppressive drugs). “B” refers to less active disease requiring lower doses of prednisolone, or symptoms that require only symptomatic therapy (e.g. antimalarials or NSAIDS). “C” denotes stable mild disease. D is for no activity in organs or systems previously affected while “E” identifies individuals in whom the particular system or organ has never been affected. The systems involved in the BILAG score are general body involvement, skin, central nervous system, musculoskeletal system, cardio-respiratory systems, vascular system, renal and haematological systems. A global BILAG score is calculated by giving any “A” score 9 points, “B” 3 points, “C” 1 point while “D” and “E” are given 0; 0-5 denotes inactive disease while 6 or more is considered to be active disease (Hay et al, 1993). For each patient, levels of anti-dsDNA autoantibodies (by ELISA using the sterile diagnostic kit, Dundee 50 u/ml), C3 (by laser nephlometer n = 0.9- 1.8 g/ml), totalScotland n = lymphocytic count and ESR were measured routinely. Disease activity in patients with RA was done by using the duration of morning stiffness (MS) in minutes, number of active joints and erythrocytes sedimentation rate (ESR) levels in the first hour according toDuck et al (1983). . Score MS (min) No of active joints ESR (mm/h) 0 0-15 0 0-24 1 16-45 1-3 25-49 2 46-89 4-8 50-74 3 > 90 > 9 > 75 Table D. Grade I: 1-3. Grade II: 4-5. Grade III: > 6 ESR was used as one of the indicators for RA disease activity All patients were subjected to the following investigations: a) Radiological for RA patients: Plain radiography for both hands, feet, and other affected joints was done. b) Laboratory • Full blood picture. • Haemoglobin percentage (HB%). • Determinations of ESR by Westergen method. • Estimation of C-reactive protein concentration (CRP) by latex agglutination. • Estimation of RF (latex fixation test). • Detection of serum creatinine. Peripheral blood mononuclear cells were obtained from 43 SLE, 43 rheumatoid arthritis (RA) patients and 43 healthy volunteers (in total). Disease activity in SLE patients was assessed using the BILAG index. The T lymphocyte subpopulations, were cultured using plates pre-sensitised with 5 ug/ml anti-CD3 . The rate of apoptosis wasin the presence or absence of 1 ug/ml of human TNF- determined at 72 hours of culture by measuring viability and by flow cytometry using the DNA-binding agent 7 aminoactinomycine D (7AAD) and propidium iodide (PI). I blocked the Fas/FasL pathway by FasL NOK1 trying to see if the effect of is due to up-regulation of this pathway. The percentage of apoptotic TTNF- lymphocytes was determined by a 3-colour flowcytometry for CD4+ and CD8+ as well as CD45+RA and CD45+RO T cells.T lymphocytes from SLE patients were more susceptible to apoptosis when in cell cycle compared with RA patients and healthy controls. After 72 hours of culture 38.3% 33.7% and 25.45% of CD4+ cells from SLE, RA patients and healthy controls were apoptotic (p= 0.001). Higher rates of TNF-alpha-induced apoptosis were seen in naïve T lymphocytes (43.3%) compared with memory phenotype (39.9%) in lupus patients. No relationship was -induced apoptosis in either naïve or memoryfound between the degree of TNF phenotypes in patients with active disease and patients in remission (p> -induced apoptosis in CD4+0.1). The results were independent of medication. TNF and CD8+ lymphocytes in lupus patients was blocked by NOK1 but the degree of blocking was not complete. Following up six patients with SLE on three successive follow up visits revealed an inverse relationship between the activity of these patients and the degree of CD4+ and CD8+ T cell apoptosis induced by TNFα. Some clinical and laboratory parameters of RA and SLE patients have been tried to be connected with the degree of CD4+ and CD8+ T cell apoptosis by TNFα. For RA, there was a proportional relationship with age, an inverse proportion with severity of the disease [as assessed by clinical spread severity index (CSSI)], while there was no relationship with disease duration, disease activity (according to Duke et al, 1983), functional status (assessed by using the score of Steinbrocker et al, 1949), and RF positivity. On the other hand, in patients with SLE, it was found that no correlation with age, disease duration, levels of anti-ds DNA, C3, ESR and the degree of CD4+ and CD8+ T cell apoptosis induced by TNF-α. Conclusions T lymphocytes from SLE patients are -induced apoptosis compared with RA andsignificantly more susceptible to TNF- healthy controls. This observation is true for CD4+ and CD8+ T lymphocyes, as well as CD45RA+ and CD45RO+ phenotypes. CD4+ and CD8+ T cell apoptosis induced , with known is inversely proportional with the patients’ activity. TNFby TNF- beneficial effects in some murine models of lupus, was found to induce apoptosis partly through its direct effect and partly by other mechanisms. The medications of lupus patients have no effect on this effect. In patients with RA, CD4+ and was related to the patient’s age and inCD8+ T cell apoptosis induced by TNF- inverse proportion with the severity of the disease, while it is not connected to disease duration, disease activity, functional status, and RF positivity. In lupus patients, there was no correlation with age, disease duration, levels of anti-ds DNA, C3, ESR and the degree of CD4+ and CD8+ T cell apoptosis induced by TNFα.