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The aim of this study was to access average delays for novogeneration of myeloid and lymphoid cells after allogeneic bone marrow transplantation (BMT) outcome and factors affecting this organization. A prospective analysis over 2 years (01/01/07 to 31/12/08) enrolling 19 children treated with allogeneic intrafamilial bone marrow transplantation. Indications for bone marrow transplantation were: aplastic anemia (3 cases), bemoglobinopathies (9 cases), myelodysplastic syndrome (1 case) and primary immunodeficiency (6 cases). Different conditioning regiments were used according to the indication. The study of immune reconstitution was based on the quantitative determination of immunoglobulin and lymphocyte subpopulation. These tests were routinely requested to 1 month, 2 months, 3 months, 6 months, 9 months and 12 months. The average time of engraftment was 18 days (12-24). A rate of CD4+T lymphocytes>200/mm3 was provided within an average of 2,5 months (1-7). The average time to obtain CD8+T lymphocytes>200/mm3 was 2 months (1-5). The humoral immune reconstitution was made within an average of 2 months (1-4). A report of CD4+/CD8+T lymphocytes>I was obtained within 10 months and a half (1-24). Univaried analysis showed a correlation between the bone marrow sex matched and the faster reorganization of CD8+T cells (p=0.042). A quantity of CD34+>6 10(6)/kg was significantly associated with the recapture of a formula lymphocyte CD4+/CD8+T>1 (p=0.03) Immune recovery post bone marrow transplantation in children begins with myeloid lineage then lymphoid B then lymphoid T The inversion of the report CD4+/CD8+T lymphocytes, seems to be influenced by the high contain of CD34+cells in the graft as well as the type of conditioning.

Apoptosis represents a particular form of programmed cell death which appears in all the damaged cells and potentially hazardous. It plays a crucial role in the development of multicellular organisms by assuring and maintaining the cellular homeostasis. Thus, apoptosis intervenes not only in the normal process of organisms' development but also in immune defence and in cancerous cells detection. Indeed, any blockage in the program of the apoptotic machinery would be responsible of some neurodegenerative and auto-immune diseases and could play a crucial role in different steps of carcinogenesis. Some researchers were very interested in studying apoptosis in hematopoietic stem cells CD34+ which could be intended to be reinfused to patients suffering from malignant diseases. They have noted that kinetic study of apoptosis of the hematopoietic stem cells CD34+ after the process of cryoconservation is also necessary. Such study permits to quantify the real and exact number of the viable hematopoietic stem cells CD34+ and therefore to eliminate such risk which would be associated with the reinfusion of apoptotic cells to patients. In this paper, we describe our contribution to hematopoietic stem cells CD34+ study by flow cytometry before and after cryopreservation by using annexin V as a specific probe allowing detection of phosphatidyl serine, one of the major features of apoptosis. But, we have noted a pronounced induction of apoptosis in peripheral mobilized blood compared to cytapheresis (after cryopreservation: 29.79% of apoptotic HSC CD34+ in peripheral mobilized blood but only 11.67% apoptotic HSC CD34+ in cytapheresis). Besides, we have noticed that hematopoietic stem cells CD34+ have had a statute of viability better than other mononuclear cells. These results put in value the reliability, the simplicity and the efficiency of flow cytometry for the analysis of apoptosis in hematopoietic stem cells CD34+ by following the intensity of fluorescence of annexin V.

Aims: To study by flow cytometry (FCM) the ploidy and the cellular cycle of nodular hidradenoma (NH) and hidradenocarcinoma (HC) and to assess the prognostic utility of this technique in such tumors., Methods: We studied retrospectively 2 HC and 11 NH one of which was considered as an atypical NH. Monoparametric study by FCM was realized on paraffin-embedded material. The extracted cells were marked by Propidium's lodure and cellular cycle was analyzed by the software Mod-Fit LT., Results: Our study showed eleven 100% diploid profiles, 10 of which had low S-phase varying between 2 and 12%. All of these 11 tumors were NH. S-phase was high (23.79%) in a single case that corresponded to the atypical NH. Two tumors showed aneuploid profiles; these corresponded to the 2 HC., Conclusion: The results of the cytometric study suit perfectly to those of the histopathologic examination. FCM could so help to establish the prognosis of these tumors. But further studies are necessary to determine the value of this technique.

Clinico-pathological study of superficial bladder cancer (pTa/pT1) informs about prognostic factors such as the size of the tumor, its uni or multifocal character, its grade and stage. Presently, these factors constitute the basis of therapeutic decision but do not allow to foresee the prognosis with certainty. Many technics have contributed to a better knowledge of such tumors; however, they have not allowed to fully master prognostic uncertainties. During the last decades, cell cycle and DNA content study by flow cytometry has been developping, bringing an additional prognostic element to various types of tumors. We have decided to study the impact of this technique to the assessment of the prognosis of superficial bladder tumors. The study concerned 65 patients presenting superficial bladder tumors (pTa/ pT1), with a follow-up of at least two years in case of not recurrence and in case of recurrence, having had a second resection with analysis of sections. Flow cytometry was applied to formol-fixed and paraffin-embedded endoscopic resection material of initial tumors by simple-labelling of DNA with propidium iodide. Following cytometric study, 35 (54%) of tumors were aneuploid and 30 (46 %) were diploid. For the diploid ones, S-phase mean value was 14.94% (from 2.72% to 33.43%); and G2M mean value was 8.3 (from 1% to 18%). The presence of an DNA- aneuploid peak had a predictive value of recurrence and progression in stage, with relative risks of 12 and 6.85 respectively. It was also correlated with the histological grade and stage. On the other hand, S-phase and G2M values had no prognostic significance.

We report a retrospective study to estimate highly active antiretroviral therapy (HAART) effect in 139 HIV infected patients. Four criteria are studied: prevalence of opportunistic infections, CD4 cell count evolution, viral load progression and mortality. Gastrointestinal side effects are the most common clinical adverse reaction (61.1 percent), and hematological side effects are the most common biological adverse reaction (61.2 percent). During the 22.8 months (3 months to 6 years) follow-up average period, CD4 cell counts remained above 500 per cubic millimeter in only 25.8 percent of cases, while 63.5 percent of patients had a viral load below 400 copies per milliliter. During the study on patients receiving HAART, opportunistic infections appeared in 17.3 percent of cases (24 cases) and mortality in 6.4 percent of cases.

The prevalence of GAD antibodies and its correlation with some autoimmune markers: ICA (islet cells antibodies), antinuclear antibodies, thyroid antithymune and antimicrosomes antibodies, were studied in 84 Tunisian type 1 diabetic children. The prevalence of GAD antibodies was 51.2% and decreased as a function of increasing duration of the disease. Their frequency was 84.6% in children with newly diagnosed diabetes (within 6 months of diagnosis) and only 29.41% in those with a longer duration of the diabetes (more than 5 years). ICA were present less frequently (21.4% of the children). 10.7% of the studied samples were positive with the two antibodies (GAD ab ICA), and 40% were positive only with GAD antibodies. We conclude that the GAD antibodies seems to be more associated to the development of type 1 diabetes than ICA. They are detected more frequently in patients with long standing disease, that's make their determination very interesting as diagnostic and predictive marker.

A human recombinant erythropoietin is produced by transfection of a human EBV immortalised lymphoblastoid cell line by human erythropoietin gene. This cell line was selected because it is eucaryotic, human, able to grow in suspension and neither clonogenic nor tumorigenic. Purification of erythropoietin from culture supernatants of lymphoblastoid cells was described and structural, biochemical and functional characteristics were investigated in several studies. Results obtained for this kind of recombinant erythropoietin were similar to those obtained regarding the protein expressed in CHO cells suggesting that both molecules have the same efficiency in clinical applications.

Among the neutrophil polynuclear specific antigens (NA, NB, ND, NE, ...), NA antigen is the most common. It is a glycoprotein situated on the neutrophils FcRIIIb-receptor and presents 2 forms: NA1 and NA2. The epitope responsible of that polymorphism has got an amino acids composition that is unknown. The first techniques used for their analysis were the microagglutination and the granulocytotoxicity-later, the immunofluorescence, the chemiluminescence and the MAIGA (Monoclonal Antibody Immobilized granulocyte Antigen) were introduced. These last years, more efficient techniques appeared like Flow Cytometry and Polymerase Chain Reaction (PCR) that allowed phenotyping and genotyping of neutrophil polymorphonuclear specific antigens. The studies indicated that NA antigen frequency varies according to the populations and the ethnics. NA2 allelic form is more frequent than NA1 in the caucasian population (88% VS 46%). In human pathology, NA antigen is implicated in the physiopathological mechanisms of the alloimmune and probably auto-immune neutropenies.

Antibodies to Hepatitis C virus (HCV) were tested in 43000 Tunisian blood donors by using enzyme immuno-assay. Our results show that 0.7% (304/43000) were anti-HVC positive. Of these 304.78 were confirmed anti-HCV positive (0.18%) by immuno-blot, and 99 displayed an indeterminate profile. Different immune responses were observed: In donors with positive serologic pattern (78/304), 25.6% response towards whole antigens (C + NS3 + NS4 + NS5) was frequently observed (44/78) 56.4%. Reactivity to 2 antigens was observed in 28.2% (22/78) and with 3 antigens in only 15.4% (12/78), with systematic reactivity to core. In donors with indeterminate serologic pattern (99/304) 32.5%, reactivity to non-structural antigen NS5 was the most frequently observed (54/99) 54.5%, reactivity to non-structural NS3 antigen was noted in 27.3% (27/99) and to core antigen in 18.2% (18/99). No donors with isolated reactivity to NS4 were observed in our series.

The early detection of microalbuminuria in insulin dependent diabetes is considered as a sign of initial stage of nephropathy possibly reversible if glycemic balance is well maintained. This detection requires very accurate methods as radio-immuno-assays. Yet, they are so slow that they represent an obstacle to systemic detection. We report in this work an apparaisement of an immuno-nephelemetric and electro-immuno-diffusion of Laurell methods. Results reveal that immuno-nephelemetry and electro-immuno-diffusion are a sensitive and accurate methods (threshold of sensitivity of Laurell method is : 2.5 mg/l and nephelemetry is 1.5 mg/l). Moreover, RIA, immunonephelemetry and Laurell methods are significantly well correlated (r = 0.903: Laurell/Radio-immuno-assay, r = 0.907: Nephelemetry/Laurell). In conclusion immuno-nephelemetry and electro-immuno-diffusion of Laurell are a choice methods to test great lines of samples. Radio-immuno-assay can be used as a reference method of detection of microalbuminuria.

Tataouine (South Tunisia) has been subject to several viral hepatitis epidemics during these last years. Prospective study has been conducted to define the prevalence of HVB infection. It has examined 511 cases, the age of whom was between 1 month and 70 years, reported in groups through the OMS recommendations, taking into account the number of inhabitants in each area. The global prevalence was 6.2% for HBs Ag and 18.5% for HBs antibody. These results were not different from the frequencies observed within the Tunisian population in general. The analysis of this study according to these groups, shows that in three areas (Ras El Oued, Bir 30, Dhibet) 60 to 80% of cases have at least one of HVB marquers, whereas the prevalence in other areas (Rogba) was very weak. The geographic repartition of HVB infection corresponds approximatively to areas that have been the most infected by the last hepatitis epidemics. A second study has completed and confirmed the results of the first one, taking into consideration a more important number of cases from areas of strong and weak endemicity. 596 sera have been examined in Rogba which counts 2000 inhabitants and is a weak endemicity area. 528 sera have been examined in the three areas of strong endemicity: 199 in Bir 30, 201 in Dhibet and 128 in Ras El Oued, which count around 2000 inhabitants, too. The percentage of cases presenting at least one of HVB serological marquers reaches 84 in Dhibet, 70 in Ras El Oued, 50 in Bir 30 and 24 in Rogba. This HBs Ag frequency is 3.8% in Rogba, 15% in Bir 30, 24% in Ras El Oued and 26.3% in Dhibet. It seems that the HVB is the virus of hepatitis epidemics observed in Tataouine at least in the three strong endemicity areas.

There is no doubt that the autoimmune process in human disease depends on genetic factors. Varying associations were noticed between HLA DR and autoimmune disorders. The frequency of HLA-A-B and DR antigens as well as the Bf and C4 allotypes have been investigated in insulinodependant diabetes mellitus (IDDM) and compared to that of healthy controls in Tunisian population. An increase of A30, DR3, DR4, BfF1, C4AQ0 and C4BQ0 and decrease of B40, DR2, DR5 and DR6 were found in diabetes when compared to the value observation controls. The strongest association was noticed with HLA, DR3 and DR4. The prospective role of DR2 and DR5 antigens were also confirmed. Examination of HLA, Bf and C4 alleles. Two supratypes associated with IDDM have been observed among the Tunisian patients.

1,400 sera taken from patients suspected of having autoimmune diseases and sent to the laboratory for determination of antinuclear antibodies, are tested by comparative indirect immunofluorescence on 2 subtrata; rat liver section and HEP/2 cells. The 143 positive sera on rat liver sections are also positive on HEP-2. In the 1,010 sera which are negative on rat liver sections, 165 are positive on HEP-2, 113 give a nuclear fluorescence, 26 give a cytoplasmic fluorescence and 26 give a nuclear and cytoplasmic fluorescence. Three positive sera were also used in immunofluorescence on another cells: VERO and MRC 5, as well as dual immunodiffusion versus thymic and splenic cell extracts and 76 p. cent of these sera were found positive with these techniques. This confirms the advantage of the use of HEP/2 cells in demonstrating autoantibodies, especially when they are not detected on rat liver sections, like the anticentromer antibodies. This substratum offers the advantage of detecting not only antibodies directed against nuclear antigens, but also those directed against cytoplasmic antigens.