Israel Medical Association Journal

Background: Experimental and clinical protocols are being developed for the cryopreservation of human hematopoietic progenitor cells. However, the effect of these procedures on the potential for HPC[1] to repopulate bone marrow is unknown.

Objectives: To examine the effect of cryopreservation on the ability of fetal human liver HPC, which include CD34+ cells and long-term culture-initiating cells, to repopulate immunodeficient non-obese diabetic/severe combined immunodeficiency mouse bone marrow.

Methods: Groups of sublethally irradiated NOD[2]/SCID[3] mice were injected intravenously with cryopreserved or freshly isolated fetal human liver HPC.

Results: Seven weeks after transplantation, flow cytometric analysis of bone marrow samples showed that mice that received the transplanted cells (either cryopreserved or freshly isolated) demonstrated both lymphoid and myeloid differentiation as well as the retention of a significant fraction of CD34+ cells. Conclusions: Cryopreserved fetal human liver-derived HPC appear to be capable of initiating human cell engraftment in NOD/SCID mouse bone marrow and open the possibility of using cryopreserved fetal human liver HPC for gene manipulation, gene transfusion therapy, and transplantation purposes.

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[1] HPC = hematopoietic progenitor cells

[2] NOD = non-obese diabetic

[3] SCID = severe combined immunodeficiency

Background: Cell-mediated immunity is impaired in uremia. Cell-matrix interactions of immune cells such as CD4+T lymphocytes with extracellular matrix are an important requirement for an intact immune response. The adherence of CD4+T cells of healthy subjects (normal T cells) to ECM components is inhibited in the presence of uremic serum. Such decreased adhesive capacity is also found in T cells of dialysis patients. Various chemokines and cytokines affect the attachment of CD4+T cells to ECM.

Objective: To evaluate chemokine (MIP-1β and RANTES) and tumor necrosis factor α-induced adhesion of CD4+T cells to ECM in a uremic milieu.

Methods: We examined adhesion of normal CD4+T cells (resting and activated) to intact ECM in response to soluble or bound chemokines (MIP-1β and RANTES) and to TNF-α following incubation in uremic versus normal serum. Thereafter, we evaluated the adhesion of resting CD4+T cells from dialysis patients in a similar fashion and compared it to that obtained from a healthy control group.

Results: Addition of uremic serum diminished soluble and anchored chemokine-induced attachment of normal resting and activated CD4+T cells to ECM compared to a normal milieu (a peak response of 10–11% vs. 24–29% for soluble chemokines, P<0.001; 12–13% vs. 37–39% for bound chemokines on resting cells, P<0.01; and 18–20% vs. 45–47% for bound chemokines on activated cells, P<0.02). The same pattern of response was noted following stimulation with immobilized TNF-α (7 vs. 12% for resting cells, P<0.05; 17 vs. 51% for activated cells, P<0.01).  Adherence of dialysis patients’ cells to ECM following stimulation with both bound chemokines was reduced compared to control T cells (15–17% vs. 25–32%, P<0.0000). In contrast, adherence following stimulation by TNF-α was of equal magnitude.

Conclusions: Abnormal adhesive capacity of T lymphocytes to ECM in uremia may, in part, be related to a diminished response to MIP-1β, RANTES and TNF-α. However, whereas reduced adhesion to chemokines was present in both normal CD4+T cells in a uremic environment and in dialysis patients’ T cells, TNF-α-induced adhesion was found to be inhibited only in normal cells in a uremic milieu.

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ECM = extracellular matrix

TNF-α = tumor necrosis factor-a

Background: Inflammation is a major component in the pathogenesis of asthma. CD14 is an endotoxin (lipopolysaccharide) receptor, and is expressed mainly on monocytes and macrophages. Binding of LPS to CD14 activates the monocyte or macrophage and causes the release of different cytokines.  The soluble form of CD14 is present in serum, and its concentration increases in several clinical conditions, including infections, auto-immune disorders, allergic disorders, and lung diseases.  The possible role of CD14/sCD14 in asthma has been investigated in a few adult patients only.

Objectives: To measure serum concentrations of sCD14 in children with status asthmaticus.

Methods: We compared serum concentration of sCD14 in 10 children with status asthmaticus measured within 24 hours of admission and after recovery from the acute episode.

Results: Levels of sCD14 were significantly higher during acute asthma attacks than at recovery.

Conclusions: The elevated serum levels of sCD14 during status asthmaticus may be the result of the activation of monocytes, macrophages or other cells.  The influence of medications on serum sCD14 cannot be ruled out.  The possible use of sCD14 as a marker of lung inflammation in asthma warrants further investigation. 

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LPS= lipopolysaccharide

SCD14= soluble form of CD14