Erythropoiesis in Fanconi's anemia.

Fanconi's anemia (FA) is an autosomal recessive condition in which greater than 90% of the homozygotes develop aplastic anemia. To determine the relation between erythroid progenitors and clinical status, blood and marrow mononuclear cells were cultured in methyl cellulose with erythropoietin, plus other hematopoietic growth factors, and growth in normal oxygen (20%) was compared with growth in low, physiologic oxygen (5%). Peripheral blood cultures were performed from 24 patients, and marrows from six.

Fanconi's anaemia and pregnancy.

We have identified six new cases of Fanconi's anaemia (FA) who had pregnancies, and reviewed 11 others from the literature. At least 110 FA females have reached 16 years of age or more, of whom 15% became pregnant. There were a total of 26 pregnancies, resulting in 19 births and 18 surviving children.

Structural and functional heterogeneity of alpha spectrin mutations involving the spectrin heterodimer self-association site: relationships to hematologic expression of homozygous hereditary elliptocytosis and hereditary pyropoikilocytosis.

Defects involving alpha spectrin (Sp) are found in patients with hereditary elliptocytosis and a related disorder, hereditary pyropoikilocytosis (HPP). We have previously found that the severity of hemolysis was related to the total spectrin content of the cells and the percentage of unassembled dimeric Sp (SpD) in the membranes, which, in turn, reflected the amount of mutant Sp in the cell. However, no data are available comparing differences in the function of various alpha Sp mutations to clinical severity.

Cellular basis of the proliferative response of human T cells to mouse xenoantigens.

Purified human T cells respond proliferatively to allogenic peripheral blood mononuclear (PBMC) stimulating cells but show no response to murine splenic stimulating cells. Two possible explanations for the lack of xenogeneic response are that human T cells, educated in a human thymus, cannot directly recognize a molecule as disparate as mouse antigen encoded by H-2 and/or that a cytokine(s) produced by the APCs is needed to allow a proliferative response and that the cytokine(s) produced by murine APC do not provide an adequate stimulus to the human T cells under these conditions. We show here that highly purified human T cells can respond directly in an antigen-specific manner to murine stimulating cells if human rIL-1 or rIL-2 or a T cell growth factor (TCGF) preparation are present in the culture.

Gamma delta beta-thalassemia due to a de novo mutation deleting the 5' beta-globin gene activation-region hypersensitive sites.

gamma delta beta-Thalassemia is a rare disorder of hemoglobin biosynthesis, characterized molecularly by partial or complete deletions of the beta-globin gene complex of 100 kilobases (kb) or greater. Common to all mutants described has been the deletion of the most-5' sequences of the beta-globin complex. We have used the techniques of pulsed-field gel electrophoresis and polymerase chain reaction to study a patient with a clinical gamma delta beta-thalassemia phenotype.

Comparison of erythroid progenitor cell growth in vitro in polycythemia vera and chronic myelogenous leukemia: only polycythemia vera has endogenous colonies.

The ability of erythroid cultures to distinguish among myeloproliferative disorders was examined. We studied 14 patients with polycythemia vera (PV), 11 with chronic myelogenous leukemia (CML), four with non-PV erythrocytosis, two with agnogenic myeloid metaplasia, as well as three normal fetuses and greater than 25 normal adults. Endogenous, i.

Effects of hemin on erythropoiesis.

It is clear that in vitro hemin increases the number of blood BFU-E derived colonies from normal donors. This occurs with sickle donors as well, despite the increased levels of hemin in vivo in these patients. The effect of hemin on relative gamma globin synthesis is inconsistent, however.

Erythrocyte characteristics in childhood acute leukemia.

Children with acute leukemia often have erythrocytes with "fetal-like" features. To examine the relationship of the type and phase of the leukemia to this observation, we studied 39 children with newly diagnosed acute lymphocytic leukemia (ALL) and 5 with acute nonlymphocytic leukemia (ANLL). In addition, 22 patients were evaluated during chemotherapy, 3 off therapy, and 12 at the time of relapse.

Differential synthesis of beta-major and beta-minor globin proteins in murine erythroleukemia cells is regulated at the transcriptional level.

We compared the transcription and translation of globin genes in three mouse erythroleukemia cell lines under different conditions in which there is differential expression of beta-major (beta ma) and beta-minor (beta mi). Transcription was measured by pulse labeling of whole cell RNA with [3H]uridine, and translation by labeling whole cell protein synthesis with [3H]leucine. Induction with dimethyl sulfoxide led to increased transcription of alpha, beta ma, and beta mi genes, and the proportion of beta mi RNA synthesized was similar to the proportion of beta mi globin protein produced, whether the cells produced 30-40% beta mi (lines 745 and 9M) or greater than 80% beta mi (clone 25-66).

Red cell size heterogeneity during ontogeny.

To determine the manner in which erythrocyte changes occur during ontogeny, several red cell parameters were analyzed in fetuses, newborn infants, children, and adults. Although mean cell volume (MCV) and hemoglobin F (HbF) levels decreased as expected during in utero development, the coefficient of variation of red cell size (%CV), or red cell distribution width (RDW), increased from fetuses to newborn infants. In normal adults, the %CV was 15 (RDW was 13).

Prenatal diagnosis: general introduction, methodology, and review.

Prenatal diagnosis of hematologic disease has been performed in more than 10,000 fetuses since 1974, with the majority at risk for thalassemia. Fetal blood sampling was the initial method, but most centers are now changing to DNA technology, particularly using specimens obtained by chorionic villus sampling. Fetal blood globin chain composition and synthesis is examined using carboxymethyl cellulose columns, electrophoresis, and high performance liquid chromatography.

Primary structure of two nonallelic beta-globin chains from DBA/2 mice.

The amino acid sequences of the beta major and beta minor globin chains from DBA/2 mice have been determined. This information is of interest because DBA/2 mice are the strain of origin for most murine erythroleukemia lines. The primary structure of DBA/2 beta globins agrees completely with that predicted from the coding properties of BALB/c beta globin genes.

Long-term growth of lymphokine-activated killer (LAK) cells: role of anti-CD3, beta-IL 1, interferon-gamma and -beta.

Peripheral blood lymphocytes (PBL) cultured in interleukin 2 (IL 2)-containing medium in conventional tissue culture develop the ability to lyse fresh tumor cells; such cells are referred to as lymphokine-activated killer (LAK) cells. LAK activity peaks by day 5 of culture and declines rapidly thereafter. We studied culture conditions and signals that allow for long-term culture and expansion of cells with LAK activity.

The stepwise activation of cytotoxic T lymphocytes.

The recognition of antigen is the first stage of T-lymphocyte maturation in vivo. Monoclonal antibodies directed against the T-cell receptor/CD3 complex and against other surface antigens can also provide this stimulus. Gianni Gromo and his colleagues are attempting to characterize the steps leading from this initial activation to full functional maturation.