Infant growth and aorta total lipid fatty acids

Abnormal fetal and infant growth have increasingly been correlated with adult onset cardiovascular disease. To date, there is little known about the lipid fatty acid profiles in infant cardiovascular tissue. Therefore, we analysed total lipid fatty acids from thoracic and abdominal aorta intima and media from 24 normally grown sudden infant death syndrome cases. Aorta from small for gestational age (n = 2), failure to thrive from birth (n = 3), and premature (n = 1) infants were also examined. Dihomo-gamma-linolenic acid (C20:3n-6) and oleic acid (C18:1n-9) concentrations were significantly lower in the thoracic than in the abdominal aorta. Similar dietary related differences were found in the subgroup (n = 15) of infants fed on formula milks. Both abdominal and thoracic intimal arachidonic (C20:4n-6) to dihomo-gamma-linolenic acid ratios were greater in the infants with retarded growth after birth than in their normally grown counterparts. Growth restriction in infancy might disrupt the normal accretion of vascular endothelial polyunsaturated fatty acids.     

Protein kinases potentially capable of catalyzing the phosphorylation of p47-phox in normal neutrophils and neutrophils of patients with chronic granulomatous disease

A procedure for uncovering novel protein kinases was used to search for enzymes in neutrophils that may catalyze the phosphorylation of the 47- Kd subunit of the NADPH oxidase system (p47-phox). This component of the oxidase can undergo phosphorylation on multiple sites. The method is based on the ability of renatured kinases to recognize exogenous substrates fixed in gels. We report that neutrophils contain several uncharacterized protein kinases that catalyze the phosphorylation of a peptide substrate that corresponds to amino acid residues 297 through 331 of p47-phox. Some of these enzymes are strongly activated on stimulation of the cells with phorbol 12-myristate 13-acetate (PMA). The results indicate that the phosphorylation of p47-phox in neutrophils may be more complicated than previously appreciated and may involve multiple protein kinases. In addition, we have examined both the renaturable protein kinases and the properties of protein kinase C (PKC) in neutrophils from patients with chronic granulomatous disease (CGD) who are deficient in cytochrome b558. Previous studies have shown that these cells exhibit incomplete phosphorylation of p47-phox on stimulation. In this study, we were unable to detect any alterations in the renaturable protein kinases or PKC in CGD neutrophils that could explain these defects in the phosphorylation of p47-phox.     

Purification and functional evaluation of mature neutrophils from human bone marrow

Human myeloid maturation proceeds within the bone marrow and results in a mature neutrophil that is released into the peripheral circulation. Previous reports have indicated that neutrophils from bone marrow demonstrate decreased adherence, impaired phagocytosis, and decreased nitroblue tetrazolium dye reduction when stimulated. Due to lack of a suitable method for isolating purified bone marrow neutrophils, these studies have been performed by microscopic techniques. We now report a method for isolating 1 X 10(8) neutrophils [bands plus polymorphonuclear leukocytes (PMNs)] from 10 mL of bone marrow aspirate sample. By means of a discontinuous Percoll-gradient centrifugation through densities of 1.085, 1.095, and 1.10 g/mL a leukocyte-rich suspension of bone marrow can be separated into three leukocyte layers. By combining the lower two leukocyte layers (M2/3), a population of neutrophils consisting of 26% bands and 63% PMNs is seen. When compared with peripheral blood PMNs, these bone marrow neutrophils had a lower alkaline phosphatase activity, decreased ingestion of Oil Red O-coated particles, impaired superoxide release on stimulation with the chemotactic peptide Fmet-leu-phe (FMLP) or the tumor promotor phorbol myristate acetate (PMA), and less activity of the NADPH-dependent oxidase. These results indicate that morphologically mature neutrophilic cells within the bone marrow exist in a still functionally immature state.     

Characterization of a hierarchy in human acute myeloid leukemia progenitor cells

Despite the usual uniform and primitive appearance of cells derived from the leukemic clone in most patients with acute myeloid leukemia (AML), there is considerable heterogeneity among leukemic blasts, particularly with respect to their capacity to proliferate and/or self renew. We have assessed whether these differences in proliferative potential are correlated with the phenotypic changes that characterize normal hematopoiesis, which might suggest an analogous hierarchy of AML progenitors. We have used the ability of primitive AML cells to persist or produce blast colony forming cells (CFU-blast) detected after 2 to 8 weeks in the presence of growth factors in suspension cultures (SC) termed SC-initiating cells (IC), or with stroma in long-term cultures (LTC-IC) as a quantitative assay for a cell that may have primitive characteristics. This SC assay is linear, cell concentration independent, and the frequency of SC-IC by limiting dilution analysis is lower than primary CFU-blast. The average output of CFU-blast after 2 to 8 weeks by individual SC-IC varied between 2 and more than 100 in individual patients. Leukemic blasts were sorted based on their expression of antigens previously found useful to characterize normal progenitor differentiation, and analyzed for the percentage of CFU- blast SC-IC, and leukemic LTC-IC within each fraction. All of these progenitor types were heterogeneous in their expression of CD45RA and CD33, but expressed uniformly low levels of CD15 and differed from normal primitive progenitors in their high expression of HLA-DR. CFU- blast had a significantly higher expression of CD71 and CD38 as compared with SC-IC or leukemic LTC-IC. In patients with CD34+ blasts, the majority of their SC-IC at 4 weeks were CD34+/CD38-; however, patients with CD34- blasts had at least some CD34- progenitors. These results show that while heterogeneity exists between patients, it is possible to physically separate subpopulations of AML cells with different proliferative potentials. It also provides some support for the concept that quantitation of leukemic cells capable of producing CFU-blast for 4 weeks or more in vitro measures a less frequent leukemic progenitor with higher proliferative potential that may be the only relevant cell for maintaining the leukemic clone in vivo.     

Kaposi's sarcoma (KS)-associated herpesvirus-like DNA sequences in peripheral blood mononuclear cells: association with KS and persistence in patients receiving anti-herpesvirus drugs

Herpesvirus-like DNA sequences (KSHV/HHV-8) have recently been described in AIDS-associated Kaposi's sarcoma (KS) lesions. Many questions remain regarding the role of this virus in KS and the therapeutic implications of this finding. In the current study, KSHV/HHV-8 DNA was detected in peripheral blood mononuclear cells (PBMCs) from human immunodeficiency virus (HIV)-infected patients with KS (34/98) more often than in HIV-infected individuals without KS (12/64, P = .03). The detection of KSHV/HHV-8 DNA did not correlate with the CD4 lymphocyte count. Five patients demonstrated KSHV/HHV-8 DNA in their PBMCs during administration of intravenous foscarnet and/or ganciclovir. The continued detection of KSHV/HHV-8 DNA in the PBMCs of patients receiving these anti-herpesvirus drugs has potential implications regarding the virus-cell relationship of KSHV/HHV-8, as well as for the value of these drugs in treating or preventing KS, but additional studies are needed.