ALBERT

Description: 1. The serum of normal individuals and of patients with Gaucher’s disease does not contain cerebrosides in measurable amounts. Cerebrosides in Gaucher’s disease are increased only in those organs containing abundant numbers of cells characteristic of the disease. 2. Normal red blood cells contain approximately 0.19 per cent cerebrosides. The cerebroside in red blood cells is a galactosidocerebroside. 3. Red blood cells in Gaucher’s disease do not differ quantitatively and qualitatively in their cerebroside content from the red blood cells of normal individuals. 4. In four different cases of Gaucher’s disease separate determinations of splenic galactosido- and glucosidocerebrosides were made. The spleen of two adults showed mainly glucosidocerebrosides and only traces of galactosidocerebrosides, while the analysis of the spleen of two other adults showed that galactosido- as well as glucosidocerebrosides may be accumulated simultaneously in Gaucher cells. These findings are of importance, since it is demonstrated that the deviation of the cerebroside metabolism in Gaucher cells not only results in the formation of an abnormal glucosidocerebroside, but also may lead to the increased formation of the normal galactosidocerebroside, kerasin. It is demonstrated that the relative proportions of galactosido- and glucosidocerebrosides in Gaucher cells may differ considerably in individual cases. 5. The organs of infantile siblings with "generalized infantile Gaucher’s" disease were analyzed. The organs of one infant showed mainly galactosidocerebrosides while in the organs of the other sibling both kinds of cerebrosides, glucosido- as well as galactosidocerebrosides, were present. 6. The findings reported in this paper lend support to the theory that Gaucher’s disease is the result of a deviation of the intracellular metabolism of reticulum cells and histiocytes. The cerebrosides are not transported by the serum or by the red blood cells and secondarily deposited in the cells involved, but are formed and stored in the reticulum cells and histiocytes were they are found.

Description: The antigenicity of the Rh variant Rho(Du) was investigated by the transfusion of 45 Rh negative (cde/cde) patients with 68 units of "low grade" Rho (Du) blood of the phenotypes Rho(ccDuee) or Rh2(ccDuE). The donor red cells had normal viability; none of the patients made antibodies to Rho(D) or Rho(Du). The results indicate that the inherited, "low grade" Rho(Du) factor is far less antigenic than Rho(D). It was also less antigenic than Kell or rh'' (E) in this study. It remains possible that this variant will prove to be antigenic in some recipients, but the hazard from this is undoubtedly much less than has been expected.

Description: Thalidomide has been reported to be an effective agent for treatment of chronic graft-versus-host disease (CGVHD). To determine the efficacy of this agent in patients with refractory CGVHD a total of 80 patients who failed to respond to prednisone (PSE) or PSE and cyclosporine (CSA) were treated with thalidomide. Sixteen patients (20%) had a sustained response, 9 with a complete remission and 7 with a partial response. Twenty-nine patients (36%) had thalidomide discontinued because of side effects, which included sedation, constipation, neuritis, skin rash, and neutropenia. Side effects were reversible with drug discontinuation except for mild residual neuritis in one case. Rashes and neutropenia have not previously been reported as thalidomide side effects when used for CGVHD treatment. We conclude thalidomide is immunosuppressive and active in the treatment of CGVHD. A high incidence of reversible side effects limited dose intensity and reduced the number of patients who could benefit from treatment.

Description: The proteinase-activated receptor-2 (PAR-2) is the second member of a putative larger class of proteolytically activated receptors that mediate cell activation events by receptor cleavage or synthetic peptidomimetics corresponding to the newly generated N-terminus. To further study the previously identified mitogenic effects of PAR-2, we used the interleukin-3 (IL-3)–dependent murine lymphoid cell line, BaF3, for generation of stable cell lines expressing PAR-2 (BaF3/PAR-2) or the noncleavable PAR-2 mutant PAR-2Arg36 → Ala36. Only BaF3 cells expressing either wild-type or mutated receptor exhibited mitogenic responses when grown in IL-3–deficient media supplemented with PAR-2 activating peptide (SLIGRL, PAR39-44). This effect was dose dependent with an EC50 of ∼80 μmol/L, sustained at 24, 48, and 72 hours, and was also demonstrable using thrombin receptor peptide TR42-47. Because tryptase shares ∼70% homology with trypsin (previously shown to activate PAR-2), we studied recombinantly expressed forms of α- and β-tryptases as candidate protease agonists for PAR-2. Hydrolytic activity of the chromogenic substrate tosyl-glycyl-prolyl-argly-4-nitroanilide acetate was present as a sharp peak at Mr ∼130, confirming the presence of secretable and functionally active homotetrameric α- and β-tryptases in transfected COS-1 cells. Dose-dependent proliferative responses were evident using either secreted form of tryptase with maximal responses seen at ∼3 pmol/L (0.1 U/L). Receptor proteolysis was necessary and sufficient for mitogenesis because active site-blocked tryptase failed to induce this response, and proliferative responses were abrogated in BaF3 cells expressing PAR-2Arg36 → Ala36. These results specifically identify both forms of mast cell tryptases as serine protease agonists for PAR-2 and have implications for elucidating molecular mechanisms regulating cellular activation events mediated by proteases generated during inflammatory, fibrinolytic, or hemostatic-regulated pathways.

Description: With the aim of determining the incidence of idiopathic thrombocytopenic purpura (ITP) in adults, we searched all adult ITP patients diagnosed from April 1, 1973 to December 31, 1995 in the County of Funen in Denmark. This county comprises 9% of the total Danish adult population. A total of 221 patients fulfilled the inclusion criteria, yielding an annual standardized incidence rate of 2.68 per 100,000. The median age of the patient population was 56 years, and the female to male ratio was 1.7. Changing the platelet count cut-off point from 100 × 109/L to 50 × 109/L changed the incidence rate to 2.25 per 100,000. Comparing patients less and more than 60 years old, the incidence rate more than doubled and the sex difference was eliminated in the older age group. These two age groups were almost identical regarding platelet count at diagnosis and number of asymptomatic cases. The incidence rate increased in the study period. This increase in particular involved asymptomatic patients and old males who were both symptomatic or not symptomatic. Including additional patients identified by a questionnaire study of the contribution from the primary care physicians and the practicing specialists in the second half of the study period, a reliable estimate of the annual ITP incidence in Danish adults, using a platelet concentration cut-off point of 50 × 109/L, is 3.2 per 100,000 persons.

Description: We report here a series of 16 highly malignant diffuse large B-cell lymphomas of the oral cavity with unique immunohistologic features. Fifteen of these developed in human immunodeficiency virus-positive patients. All cases displayed morphologic features of diffuse large-cell lymphomas but strikingly differed from them in that they showed a minimal or absent expression of the leukocyte common antigen as well as of the B-cell antigen CD20. Instead, the tumor cells showed a constant reaction with the plasma cell characteristic antibody VS38c and a frequent reaction with the CD79a antibody. This, in conjunction with a variable expression of cytoplasmic Ig and a monoclonal rearrangement of the Ig heavy chain gene in all of the three tested cases confirmed the B-cell nature, the clonal origin, and the plasmacellular differentiation of these neoplasms. The majority of these tumors were negative for the BCL-6 protein, with the remaining cases showing only a partial and weak expression of this antigen. An association with the Epstein-Barr virus (EBV) was found in 9 of 15 tested cases showing abundant EBV-encoded nuclear RNA transcripts in the absence of EBNA-2. Five of the EBV-positive cases variably expressed LMP-1. We propose to name these tumors plasmablastic lymphomas, in accordance with their morphologic and immunohistologic features. Knowledge of this lymphoma entity is important to avoid confusion with nonlymphoid malignancies due to the lack of commonly used lymphoid markers.

Description: Interleukin-12 (IL-12) is a potent proinflammatory and immunoregulatory cytokine skewing T lymphocytes to express a type 1 cytokine pattern. Optimal expression of IL-12 mRNA and bioactivity in vitro requires specific priming of monocytes by interferon-γ (IFN-γ) or granulocyte-macrophage colony-stimulating factor (GM-CSF) before lipopolysaccharide (LPS) stimulation. We show here for the first time that the production of IL-12 by IFN-γ– or GM-CSF–primed human monocytes can be completely suppressed by preincubation with LPS (fromEscherichia coli Serotype 055:B5) for 6 to 24 hours before the priming procedure. A dose-dependent suppression of IL-12p70 was measured on the levels of intracellular cytokine production and cytokine secretion. mRNA studies on the expression of p40 and p35 showed an LPS-induced downregulation of both subunits. The results of several different experimental approaches suggest that IL-12 downregulation was not due to endogenous IL-10, IL-4, prostaglandin E2 (PGE2), tumor necrosis factor- (TNF-), or nitric oxide (NO) production induced by LPS. Moreover, preincubation of monocytes with LPS did not lead to a downregulation of the CD14 antigen, which is an LPS receptor. LPS preincubation in this experimental setting did not result in a general hyporesponsiveness of the monocytes, as IL-6 production as well as IFN-γ–induced upregulation of CD54 did not decline. Downregulation of IL-12 was not due to changes in mRNA stability. These findings show that the immunoregulatory important cytokine, IL-12, underlies itself a complex regulation.

Description: Tumor cells have been found in autologous hematopoietic cell transplants used after high-dose chemotherapy. To specifically eliminate contaminating mammary tumor cells during ex vivo expansion of CD34+ hematopoietic progenitor cells, we used recombinant immunotoxins (ITs) directed against cell-surface antigens expressed on mammary carcinoma cells. ITs were expressed from fusion cDNAs combining a single-chain antibody fragment (scFv) directed against the Erb-B2 or epidermal growth factor (EGF) receptors with a truncatedPseudomonas exotoxin A fragment devoid of its cell-binding domain. CD34+ hematopoietic progenitor cells did not express Erb-B2 and EGF receptors as detected by Western blotting. Ex vivo expansion of total hematopoietic cells or of colony-forming cells from CD34+ progenitors in the presence of stem-cell factor (SCF), interleukin-1 (IL-1), IL-3, IL-6, and erythropoietin (Epo) was not affected when ITs were added to the cultures. In contrast, MDA-MB 453 and MCF-7 mammary carcinoma cells were depleted in a dose- and time-dependent manner by more than 3 log in coculture with CD34+ cells over a period of 7 days in the presence of 100 to 1,000 ng/mL of anti–Erb-B2 IT. This included elimination of the subpopulations with regrowth potential. Similarly, addition of either anti–Erb-B2 or anti-EGF receptor ITs to primary breast cancer cells isolated from patients with metastatic disease resulted in elimination of cytokeratin-positive cells in seven of seven samples. ITs are highly efficient and convenient to use for the depletion of mammary tumor cells during ex vivo expansion of hematopoietic progenitor-cell autografts.

Description: Interferon consensus sequence binding protein (ICSBP) was first identified as a transcription factor of the interferon (IFN) regulatory factor family (IRF) which regulates expression of IFN-dependent genes by binding to DNA at specific sites, IFN-stimulated responsive elements. Analysis of ICSBP-deficient mice showed hematologic alterations similar to chronic myelogenous leukemia (CML) in humans and suggested a novel role for ICSBP in regulating proliferation and differentiation of hematopoietic progenitor cells. Here we show that ICSBP-mRNA expression is impaired in human myeloid leukemias: 27 of 34 CML patients (79%) and 21 of 32 patients with acute myeloid leukemia (AML) (66%) showed very low or absent transcript numbers of ICSBP. In contrast, only 2 of 33 normal volunteers (6%) showed low transcription of ICSBP(P