Zacharie Brahmi

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Unrelated cord blood (UCB) is being used as a source of alternative hematopoietic stem cells for transplantation with increasing frequency. From November 1994 to February 1999, 30 UCB transplant procedures were performed for both malignant and nonmalignant diseases in 27 children, aged 0.4 to 17.1 years. Patients received either HLA-matched (n = 3) or 1- or(More)
Major histocompatibility complex (MHC) class II antigens are expressed on human foreskin keratinocytes (HFKs) following exposure to interferon gamma. The expression of MHC class II proteins on the cell surface may allow keratinocytes to function as antigen-presenting cells and induce a subsequent immune response to virus infection. Invariant chain (Ii) is a(More)
The mechanisms underlying the massive gastrointestinal tract CD4 T-cell depletion in human immunodeficiency virus (HIV) infection are not well understood nor is it clear whether similar depletion is manifest at other mucosal surfaces. Studies of T-cell and virus dynamics in different anatomical sites have begun to illuminate the pathogenesis of(More)
OBJECTIVE The presence of small numbers of cells of donor origin in the circulation of recipients of organ transplants (microchimerism) may correlate with immunologic tolerance. As part of our ongoing studies on microchimerism, we evaluated the utility of seven PCR-based assays for the detection of the less abundant DNA in paired mixtures (100 ng total(More)
Natural killer (NK) cells play an important role in innate and adaptive immune responses to obligate intracellular pathogens. Nevertheless, the regulation of NK cell trafficking and migration to inflammatory sites is poorly understood. Exodus-1/MIP-3alpha/LARC, Exodus-2/6Ckine/SLC, and Exodus-3/MIP-3beta/ELC/CKbeta-11 are CC chemokines that share a unique(More)
Our laboratory has previously demonstrated that natural killer (NK) cell-mediated cytotoxicity is protein kinase C (PKC)-dependent and that PKC is translocated from the cytoplasm to the plasma membrane during NK cell activation. Furthermore, exposuring NK cells to a sensitive target cell for 4-6 hr at 37 degrees C rendered NK cells functionally inactive and(More)
Lysis of target cells (TC) by cytolytic lymphocytes involves the secretion of cytoplasmic granules containing perforin and serine esterases by the effector cell (EC). Recently, a granule-independent cytolytic mechanism involving the interaction of the apoptosis-triggering Fas antigen (CD95) with Fas ligand (FasL) has been revealed in T cells. However,(More)
OBJECTIVE The primary function of chemokines is the regulation of leukocyte trafficking by stimulating directional chemotaxis. The chemokine CXCL14 (BRAK) is highly expressed in all normal tissues, but is not expressed in most malignant tissues. The chemotactic activity of CXCL14 has been difficult to characterize. Recently it was reported that CXCL14 is a(More)
We investigated the inactivation of human NK cells, a population of large granular lymphocytes (LGL), with K562, an NK-sensitive target cell (TC) and KLCL, an NK-resistant TC, but which can be lysed by NK cells via antibody (Ab)-dependent cellular cytotoxicity. NK-enriched effector cells (ECc) were first treated with either K562 or Ab-coated KLCL (Ab-KLCL).(More)
C57BL/6J male mice were inoculated with 5 X 10(5) B16a melanoma cells. Seven days post-inoculation, when the tumor had grown to 8.0-10.0 mm in diameter, 120 tumor-bearing mice were randomly divided into three groups: (1) sham-irradiated controls, (2) mice receiving 200 cGy five times a week for 6 weeks, and (3) mice receiving 800 cGy once a week for 4(More)