Efficient retroviral transduction of human B-lymphoid and myeloid progenitors: marked inhibition of their growth by the <Emphasis Type="Italic">Pax5</Emphasis> transgene

We applied a coculture system for the genetic manipulation of human B-lymphoid and myeloid progenitor cells using murine bone marrow stromal cell support, and investigated the effects of forced Pax5 expression in both cell types. Cytokine-stimulated cord blood CD34⁺ cells could be transduced at 85% efficiency and 95% cell viability by a single 24-h infection with RD114-pseudotyped retroviral vectors, produced by the packaging cell line Plat-F and bicistronic vector plasmids pMXs-Ig, pMYs-Ig, or pMCs-Ig, encoding EGFP. Infected CD34⁺ cells were seeded onto HESS-5 cells in the presence of stem cell factor and granulocyte colony-stimulating factor, allowing the extensive production of B progenitors and granulocytic cells. We examined the cell number and CD34, CD33, CD19, and CD20 lambda and kappa expressions by flow cytometry. Ectopic expression of Pax5 in CD34⁺ cells resulted in small myeloid progenitors coexpressing CD33 and CD19 and inhibited myeloid differentiation. After 6 weeks, the number of Pax5-transduced CD19⁺ cells was 40-fold lower than that of control cells. However, the expression of CD20 and the κ/λ chain on Pax5-transduced CD19⁺ cells suggests that the Pax5 transgene may not interfere with their differentiation. This report is the first to describe the effects of forced Pax5 expression in human hematopoietic progenitors.     

Relationship between hyperinsulinemia and remnant lipoprotein concentrations in patients with impaired glucose tolerance

This study was performed to explore further the association between insulin resistance and plasma remnant lipoprotein (RLP) concentration. For this purpose we used the sum of the plasma insulin concentrations before and 30, 60, 90, 120, and 180 min after a 75-g oral glucose load (sigmaIRI) as a surrogate measure of insulin resistance in 61 subjects with impaired glucose tolerance. SigmaIRI was determined on 2 occasions, before and 16 weeks after initiation of a diet and exercise program. At baseline, sigmaIRI correlated with the sum of the plasma glucose concentrations in response to the 75-g oral glucose load (r = 0.26; P < 0.04) as well as plasma concentrations of triglyceride (r = 0.21; P = 0.09), RLP-cholesterol (r = 0.41; P < 0.001), and RLP-triglyceride (r = 0.46; P < 0.001). In contrast, neither total (r = 0.07) nor high density lipoprotein (HDL) cholesterol (r = 0.04) concentrations correlated with sigmaIRI. SigmaIRI was lower in 42 subjects following life-style intervention, associated with significant (P < 0.005) reductions in sigmaglucose, and fasting glucose, insulin, triglyceride, RLP-cholesterol, and RLP-triglyceride concentrations. However, none of these variables decreased in the 19 subjects whose sigmaIRI did not fall. Finally, the change in sigmaIRI following intervention with diet and exercise was significantly associated with differences in sigmaglucose (r = 0.63; P < 0.001) and fasting glucose (r = 0.26; P < 0.05), insulin (r = 0.79; P < 0.001), triglyceride (r = 0.29; P < 0.03), RLP-cholesterol (r = 0.71; P < 0.001), and RLP-triglyceride (r = 0.49; P < 0.001) concentrations. These results demonstrate that variations in concentrations of RLPs are highly correlated with changes in sigmaIRI, consistent with the possibilities that 1) RLP measurements are useful estimates of insulin resistance; and 2) an increase in RLP concentrations may provide the mechanistic link between insulin resistance and coronary heart disease.     

Gastric adenocarcinoma of the fundic gland type shares common genetic and phenotypic features with pyloric gland adenoma

Gastric adenocarcinoma of the fundic gland type (GAFG) and pyloric gland adenoma (PGA) have recently been recognized as rare types of neoplasia. We performed comparative immunohistochemical and genetic analyses of 3 GAFGs and 12 PGAs. All of the 3 GAFGs were diffusely positive for pepsinogen‐I, MIST1 and MUC6, indicating the predominantly chief cell/mucous neck cell differentiation of these tumors. A small number of H.K‐ATPase‐positive parietal cells were also scattered. PGAs invariably exhibited diffuse MUC6 and TFF2 expression, consistent with the pyloric gland differentiation of these tumors. Ten of the 12 PGAs also unexpectedly exhibited focal expression of pepsinogen‐I and MIST1, suggesting that PGAs often show focal chief cell differentiation and phenotypically resemble mucous neck cells rather than pyloric glands. The mutation analyses revealed activating GNAS mutations, which have been reported to be frequently detected in PGAs, in two of the GAFGs. While GAFGs and PGAs are morphologically distinct lesions, our observations showed their partially overlapping immunohistochemical profiles and shared presence of GNAS mutations, in addition to their common occurrence in the fundic gland mucosa. Based on these observations, we suggest that both GAFGs and PGAs are closely related lesions characterized by a mucous neck cell/chief cell lineage phenotype.     

HLA-B52-positive vasculo-Behçet disease: usefulness of magnetic resonance angiography, ultrasound study, and computed tomographic angiography for the early evaluation of multiarterial lesions

We report a case of HLA-B52-positive Behçet disease accompanied by multiarterial lesions. A 24-year-old woman was suffering from sporadic high fever and recurrent oral and genital ulcers, and laboratory data revealed severe inflammation. A diagnosis of Behçet disease was made. Magnetic resonance angiography, ultrasound study, and computed tomographic angiography demonstrated multiarterial lesions that had caused no symptoms. These noninvasive examinations were extremely useful in evaluating asymptomatic early vascular lesions.     

A clinical comparison of unrelated cord blood transplantation and unrelated bone marrow transplantation for adult patients with acute leukaemia in complete remission

We performed a clinical comparison of unrelated cord blood transplantation (UCBT) and unrelated bone marrow transplantation in adult acute leukaemia patients in complete remission (CR) who received the same conditioning regimen, graft-versus-host disease (GvHD) prophylaxis and supportive treatment. The incidence of acute GvHD was almost the same between the two groups, but the haematopoietic recovery was delayed and the incidence of chronic GvHD was higher in the UCBT group. The probability of 2 year disease-free survival was similar between the two groups. These results suggest that adult acute leukaemia patients in CR without a suitable donor should be considered as candidates for UCBT.