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C Hubbell

Publications and source records attributed to C Hubbell.

17 recordsLinked to original sources
PubMed1999

Shorter turn-around-time and improved patient care in peripheral blood progenitor cell collection procedures.

The collection of peripheral blood progenitor cells (PBPC) requires the combined efforts of the Transfusion Medicine/Hemapheresis and Hematology/Oncology services and HLA/Progenitor Cell and Immunology laboratories. Coordination and communication among these different services and laboratories are key to attaining an optimal collection in a timely manner for the patient undergoing PBPC collection. In an effort to improve patient care by same-day decision to cease or continue collections avoiding unnecessary collections, needless patient trips to the hospital and ultimately increasing patient satisfaction, a flow chart was used to capture the sequence of events. The flow chart served as a powerful tracking tool that defined system process and steps to attain enumeration of CD34+ cells the same day of collection. It provided documentation of work flow from each of the independent operations involved in progenitor cell collection and enumeration turn-around-time including attending and staff time involvement. By using the flow chart, potential and actual problem areas were demonstrated and this allowed for creative thinking and problem solving by individual sections rather than recriminations. Finally, it focused all the staff involved in the common goal of a shorter turn-around-time for CD34+ cell enumeration the same day of collection. This allowed a prompt decision for subsequent leukapheresis as improved service to oncology patients and their physicians.

Adult↗
PubMed1988

Variation in indirect cell-mediated lympholysis.

The ability of an allograft recipient to respond to donor mononuclear cells in an indirect cell-mediated lympholysis (ICML) assay is an in vitro correlate of allograft rejection, but the value of this correlation depends upon the assay's reliability. We had observed inconsistency in the cytotoxic response of normal human mononuclear cells (MNC) to the same allogeneic stimulator MNC when cytotoxicity was measured repeatedly on different occasions by micro-ICML. We, therefore, investigated the extent and reasons for this inconsistency. Method variation, determined by duplicate ICML of 18 stimulator: responder MNC, was not statistically significant. Variation in cytotoxicity over time was greater but still not statistically significant. The contribution to method variation of 51Cr release from 3 different sets of target cells, cultured and labeled in duplicate, was minimal (6.33%). We then asked if in vitro generation of effector MNC under laboratory conditions was a major cause of ICML variation. We tested this using a stable transplant's in vivo sensitized effector cells against donor MNC in a direct CML (DCML) and obtained consistent results. Finally, to gain an understanding of some of the factors which might influence the generation of in vitro cytotoxicity, we measured the frequencies of cell surface antigens (DR, TAC, transferrin, Leu 2 and 3) concomitantly with ICML on day 6 of culture. Statistical analysis of the results led us to conclude that the micro-ICML is reproducible. The magnitude of lysis depends upon activated target cells (TAC- and transferrin-positive) and an increase in the proportion of helper/inducer to cytotoxic/suppressor T-lymphocytes during effector cell generation.

Antigens, Surface↗
PubMed1987

Quantitative assay of human T-cell leukemia/lymphoma virus transformation.

The in vitro transformation of normal T-lymphocytes by human T-cell leukemia/lymphoma virus (HTLV-I) is possible utilizing cocultivation techniques. We now report on a quantitative assay for HTLV-I transformation. Transformed cell lines were produced by cocultivation of either preactivated (phytohemagglutinin and T-cell growth factor) or nonactivated peripheral blood mononuclear cells with an equal number of lethally irradiated HTLV-I-positive donor cells (MT-2). After 14 days in liquid culture, transformed cells were plated in a 2-layer soft agarose system with or without T-cell growth factor (TCGF). Colony formation among 50 normal controls was observed at varying efficiencies with a mean number of 179 colonies (range, 6-599) in the presence of TCGF (up to a 2-log difference). The day 14 T-cell cultures demonstrated relatively low colony-forming efficiencies (less than or equal to 0.1%) and enhanced colony formation in the presence of TCGF. Day 14 after cocultivation was chosen for this assay based on a dose-response relationship between colony formation and the virus-positive donor cell inoculum and the known kinetics of colony growth of normal activated T-cells. An analysis of individual colonies indicated that they were of target cell origin and HTLV-I positive. Recombinant beta-interferon in increasing concentrations caused a decrease in colony formation as measured in this assay. Long-term cell cultures (2-18 months) showed higher colony-forming efficiencies (up to 1.0%) which were not enhanced by TCGF. The ability to quantitatively evaluate transformation via colony counts will provide an opportunity to study differences in transforming efficiencies attributable to varying target cells, donor cells, or blocking factors such as interferons, drugs, or anti-HTLV-I antibodies.

Cell Line↗
PubMed1984

Association of HLA-DR antigens with the autologous mixed lymphocyte reaction.

A study was performed to evaluate the association of HLA-DR antigens with the proliferative response of T cells in autologous mixed lymphocyte cultures. Peripheral blood mononuclear cells from 100 normal healthy individuals were typed for HLA-DR antigens and autologous mixed lymphocyte cultures were established. A low proliferative response from autologous cultures was found with individuals bearing HLA-DR3 antigens and in individuals with only one identifiable HLA-DR antigen. In contrast, a strong proliferative response was associated with HLA-DR6 and two identifiable HLA-DR antigens. These data are consistent with the hypothesis that HLA-DR3 antigens are associated with a weak immune response gene and HLA-DR6 antigens are associated with a strong immune response gene.

Adult↗
PubMed1984

Efficient transformation of previously activated and dividing T lymphocytes by human T cell leukemia-lymphoma virus.

Modifying previously reported techniques, we attempted to increase the efficiency of human T cell leukemia-lymphoma virus (HTLV) transformation of human T lymphocytes. Lethally irradiated donor cells (DCs) were cultured with target mononuclear cells (TMCs). DCs included ten HTLV+ T cell lines with varying degrees of virus expression or seven cell lines that do not express HTLV. TMCs were prepared from 20 cord and 16 adult peripheral blood samples, including eight patients with acquired immunodeficiency syndrome (AIDS). TMCs were either added directly to the DCs or were first stimulated with phytohemagglutinin (PHA) (5 micrograms/mL) and grown in T cell growth factor (TCGF) prior to exposure to DCs. The presence of integrated HTLV proviral DNA in the transformed cells was determined by dot blot hybridization, utilizing a cloned probe to the HTLV-I genome. HTLV production by transformed TMCs was assessed for HTLV p19, reverse transcriptase, and virus particles. No transformation occurred with T cell donor lines that do not express HTLV. Low virus expressor DCs could only, with rare exception, transform preactivated TMCs. High-titer virus-producing DCs could transform activated and nonactivated cord blood cells and activated adult TMCs. Only MT-2 could routinely transform nonactivated normal adult and activated AIDS TMCs. HUT 102 B2 could transform only one activated AIDS sample, the cells of which initially expressed HTLV-like proteins and virions. Transformed cell lines contained subsets of mature T lymphocytes with variable HTLV expression. Prior activation and culture of the T lymphocytes increases the probability and rate of transformation by HTLV, allowing for biologic detection of low HTLV-producing cells and for in vitro expansion of T lymphocyte subsets from selected patients.

Acquired Immunodeficiency Syndrome↗
PubMed1983

Prognostic significance of the revised French-American-British classification for acute lymphocytic leukaemia.

The French-American-British (FAB) classification of acute lymphocytic leukaemia (ALL) has recently been modified to improve its reproducibility. We therefore thought it beneficial to test the utility of this modified classification in the prognosis of children with ALL. Eighty-eight patients of less than 18 years of age with ALL were subtyped according to the modified FAB classification by two independent observers. The initial concordance was 86%. Seventy per cent of the patients were subtyped as L1, 27% as L2 and 3% as L3. Patients with L3 subtype were not analysed further. No significant differences were observed between L1 and L2 subtypes when the distribution of other prognostic factors were examined. No differences were observed between L1 and L2 subtypes in the achievement of complete remission. Patients with L1 morphology demonstrated no significant increased duration of first remission or survival when compared to patients with L2 morphology. We conclude that the morphology of lymphoblasts may not be an independent prognostic variable in patients with ALL.

Bone Marrow↗
PubMed1981

HLA antigens and childhood acute lymphocytic leukaemia.

HLA-A and -B antigens were determined for 94 children with acute lymphocytic leukaemia (ALL) and for 376 normal controls. Sixty-four of these 94 patients were typed for lymphocyte surface markers and 59 were defined as 'null cell' ALL. There was no difference in the distribution of the HLA-A or -B locus antigens between the control group and the entire group of patients with ALL or the 'null cell' subgroup. Patients with HLA-A9 determinants had a significant increase in early, first remission duration compared to patients without HLA-A9. This was particularly evident in the 'null cell' ALL subgroup. In addition, HLA-A9 appeared to be an independent factor affecting the length of first remission since there was no correlation between known prognostic factors such as patient age, sex or WBC and the presence or absence of the HLA-A9 antigen. Survival for the first 12-18 months was also greater in the HLA-A9 group than in the non-HLA-A9 population. Thus, the presence of HLA-A9 appears to be associated with some protective effect among patients with ALL.

Adolescent↗
PubMed1980

Regional enteritis: evidence for genetic transmission by HLA typing.

Lymphocytes from kindreds containing five sibling pairs affected with regional enteritis were typed to ascertain the association between histocompatibility leukocyte antigens (HLA)-A and -B and regional enteritis. Also, the frequency of HLA antigens in 22 patients with nonfamilial cases of regional enteritis was compared to the frequency in 402 normal blood donors. No HLA haplotype was found in more than one kindred, and no HLA antigen was more prevalent in nonfamilial cases of regional enteritis than in the normal population. In the five affected sibling pairs, four shared both haplotypes (HLA identical), and one shared one haplotype. Only one unaffected sibling shared two haplotypes with an affected proband. The high frequency of HLA identity in affected siblings and the low frequency of identity in unaffected siblings suggest linkage between the histocompatibility locus and the development of regional enteritis. There appears to be a genetic component in kindreds with regional enteritis.

Chromosome Mapping↗
PubMed1979

Demonstration of a dog liver immunosuppressive factor active in vitro.

These studies define the presence of an immunosuppressive factor in dog liver that is active in vitro. A crude dog liver extract was prepared by saline extraction and ultracentrifugation. In vitro immunosuppressive activity of the extract was assayed by its influence on standard phytohemagglutinin mitogen stimulation assays (PHA), two-way mixed lymphocyte culture (MLC) reactions, and primed lymphocyte culture (PLC). In six experiments with four extracts, the mean percentage of inhibition (MPI) of dog lymphocytes in PHA mitogen stimulation assays was 102.0 +/- 3.6. In two human MLC experiments, the extract produced an MPI of 102.3 +/- 0.3. In one canine MLC the MPI was 102.5. In three PLC experiments the MPI was 92.7 +/- 8.0, indicating that the extract inhibited sensitization. Cytotoxicity of the extract was shown not to be the mechanism of proliferation inhibition by restimulation of cells washed free of extract, concurrent eosin viability studies, and documentation of normal base proliferation of cells after extract was washed from them. We concluded that there is a naturally occurring immunosuppressive agent in dog liver that is active in vitro as demonstrated by inhibition of PHA MLC, and PLC cellular proliferation assays. The activity is not attributable to cytotoxicity.

Animals↗
PubMed1978

Actin from diploid and haploid cells of the myxomycete Physarum flavicomum--comparison with skeletal muscle actin.

Glycerinated diploid microplasmodia of Physarum flavicomum exhibited ATP-dependent contractility typical of actomyosin controlled systems. Actin was isolated from microplasmodia, haploid amoebae-swarm cells, and rabbit skeletal muscle, by classical methods as well as ATP-DEAE cellulose chromatography, and isoelectric focusing. Actins from all three sources had isoelectric points in the pH 6.5-7.0 range, and behaved similarly during the various isolation procedures. SDS-gel electrophoresis revealed that the actin from microplasmodia and muscle had a molecule weight of about 46,000 daltons while the amoebae-swarm cells possessed proteins of molecular weights of about 46,000 and 51,000 daltons.

Actins↗
PubMedDate not supplied

Neonatal herpes simplex pneumonitis.

Four new cases of neonatal herpes pneumonia and five cases from the literature were assessed. Clinical presentations, laboratory abnormalities, and radiographic features were analyzed in an effort to establish helpful criteria for early institution of antiviral therapy. Any neonate who develops respiratory distress between the third and 14th days of life and has a chest radiograph that reveals prominent hilar with a central interstitial infiltrate is at high risk for herpes pneumonia. Antiviral therapy pending antigen detection and culture results should be strongly considered in any such patient when the etiology of pneumonitis is unknown and any of the following is found: (1) thrombocytopenia; (2) evidence of disseminated intravascular coagulation; (3) elevated values in liver function tests; (4) a positive result in a rapid screening test for herpes simplex virus; (5) lymphocytic pleocytosis of the cerebrospinal fluid; (6) development of vesicular skin lesions; or (7) further deterioration in clinical status during treatment with antibiotics.

Female↗
PubMedDate not supplied

Association of renal graft survival with matching at the HLA-DR locus.

The influence of HLA-DR antigen matching in 70 cadaver transplants was studied for up to four years. The overall cumulative renal graft survival at one year was 62 percent, and at two and four years it was 60 percent. The one, two, and four year cumulative graft survival for patients receiving one or two HLA-DR antigen matched grafts was 74 percent, 69 percent, and 69 percent, respectively. In contrast, the one, two, and four year cumulative graft survival for patients receiving zero HLA-DR antigen matched grafts was 51 percent, 47 percent, and 47 percent, respectively. The cumulative graft survival for patients receiving one or two HLA-DR antigen matched grafts was significantly different (p less than 0.05) than for patients receiving zero HLA-DR antigen match grafts. No significant difference in the distribution of other prognostic factors were observed between patients receiving one or two HLA-DR antigen match grafts and patients receiving zero HLA-DR antigen matched grafts. The present authors concluded that matching for HLA-DR antigens exerts an independent beneficial effect on renal graft survival in transplant patients, most of whom have been previously transfused.

Adolescent↗