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Biomedical subjects

H Ullum

Publications and source records attributed to H Ullum.

At least 37 records · Page 2Linked to original sources

Changes in plasma concentrations of interleukin-6 and interleukin-1 receptor antagonists in response to adrenaline infusion in humans.

To investigate the possible role of adrenaline in the response of interleukin (IL)-6 and IL-1 receptor antagonists (ra) to extreme physiological conditions such as trauma and exercise, we examined the concentrations in the plasma of these cytokines during an adrenaline infusion. Given the fact that HIV infected patients have elevated levels of IL-6 in plasma, 12 HIV seropositive subjects and 6 HIV seronegative control subjects received a 1-h adrenaline infusion. Baseline concentrations of IL-6 and IL-1ra were higher in the HIV patients compared with the controls (P<0.05 and P<0.01, respectively), being most pronounced in the untreated subgroup of HIV infected patients (n = 6). The plasma concentration of adrenaline had increased 24-fold after 15 min of adrenaline infusion. The plasma concentration of IL-6 had increased by two- to threefold after 45 min of adrenaline infusion (P<0.01) and was still elevated 1 h after the infusion had ended (P<0.001 and P<0.05 in controls and HIV infected patients, respectively). The plasma concentration of IL-1ra had increased two- to threefold 1 h after ceasing the adrenaline infusion (P<0.05 and P<0.01 in controls and HIV infected patients, respectively). The relative increase in the cytokine levels was similar in controls and HIV infected patients. Thus, HIV infection did not influence the effect of adrenaline on IL-6 and IL-1ra. The present study supports the existence of a relationship between the plasma concentration of adrenaline and IL-6. It is possible that an increased adrenaline concentration in plasma induces a continued de novo synthesis of IL-6, thereby increasing plasma IL-6 in a time-dose dependent manner.

Adult↗

Adrenaline-induced mobilization of T cells in HIV-infected patients.

The present study aimed to investigate lymphocyte mobilization from peripheral cell reservoirs in HIV-infected patients. Nine HIV-infected patients on stable highly active anti-retroviral therapy (HAART), eight treatment-naive HIV-infected patients and eight HIV- controls received a 1-h adrenaline infusion. The adrenaline infusion induced a three-fold increase in the concentration of lymphocytes in all three groups. All HIV-infected patients mobilized significantly higher numbers of CD8+ cells but less CD4+ cells. All subjects mobilized CD45RA+CD62L+ and CD8+CD28+ cells to a lesser extent than CD45RO+CD45RA- and CD8+CD28-cells. Furthermore, high numbers of CD8+CD38+ cells were mobilized only in the HIV-infected patients. It was therefore predominantly T cells with an activated phenotype which were mobilized after adrenaline stimulation. It is concluded that the HIV-associated immune defect induced an impaired ability to mobilize immune-competent cells in response to stress stimuli. Furthermore, the study does not support the idea that CD4+ T cells are trapped in lymph nodes by HIV antigens, because untreated and HAART-treated HIV-infected patients mobilized similar numbers of CD4+ T cells. Finally, no evidence was found for the existence of a HAART-induced non-circulating pool of CD4+ T cells.

ADP-ribosyl Cyclase↗

Effects of subcutaneous interleukin-2 therapy on phenotype and function of peripheral blood mononuclear cells in human immunodeficiency virus infected patients.

In the context of clinical therapy with recombinant human interleukin-2 (IL-2), we monitored immunological alteration in 10 human immunodeficiency virus type-I (HIV-1)-infected individuals, on stable antiretroviral therapy, who had a CD4+ cell count between 200 and 500 cells/mm3. Subcutaneous IL-2 was prescribed thrice weekly (at a dose of 3 x 10(6) IU) for 24 weeks and the patients were followed-up for 32 weeks. IL-2 treatment induced an increase in the CD4+ percentage (P<0.001) and CD4+ cell count (P<0.009). Furthermore. natural killer (NK) cell activity was increased (P<0.001) at week 8 of treatment, whereas lymphokine-activated killer (LAK) cell activity showed a transient, nonsignificant increase at week 8 and was reduced (P<0.001) at 32 weeks. However, the cytotoxic T-lymphocyte (CTL) activity decreased against HIV antigens, and the proliferative response to Candida, IL-2 and phytohaemagglutinin (PHA) declined during the first 8 weeks (P<0.05) and returned to baseline levels after 32 weeks. The HIV RNA level did not change during IL-2 therapy; however, after 8 weeks of follow-up a significant increase (P<0.001) in viral load was observed. In

Adult↗

Immunological and virological changes in antiretroviral naïve human immunodeficiency virus infected patients randomized to G-CSF or placebo simultaneously with initiation of HAART.

To determine the efficacy of combined G-CSF and highly active antiretroviral treatment (HAART), a randomized, double blind, placebo controlled study was conducted. Treatment naive human immunodeficiency virus (HIV) infected patients were randomized to receive either placebo or G-CSF (0.3 mg/ml, 3 times a week) for 12 weeks and HAART simultaneously. The trial was terminated prematurely after interim analysis performed because of a case of severe encephalopathia in the G-CSF group. At that point 11 HIV infected patients with a CD4+ T cell count < 350/mm3 had been randomized to the G-CSF group (n = 6) or placebo group (n = 5). In both groups plasma HIV RNA decreased significantly in response to HAART. However, plasma HIV RNA changed significantly different between the two groups with the decrease being less pronounced in the G-CSF group (P = 0.02). The concentrations of CD4+ memory T cells and CD8+ naive and memory T cells increased in response to HAART, and there was a trend towards more pronounced increases in several T-cell subpopulations in the G-CSF group. The CD56+ NK cells increased significantly more in the G-CSF group compared with placebo (P = 0. 000). All patients in the G-CSF group reported bone pain. The present data do not support simultaneous administration of G-CSF with initiation of HAART in treatment naive HIV infected patients.

Adult↗

Effects of G-CSF on telomere lengths in PBMCs from human immunodeficiency virus-infected patients: results from a randomized, placebo-controlled trial.

Telomeres are unique terminal chromosomal structures, the length of which has been shown to decrease with cell division in vitro and with increased age in vivo for human somatic cells. In human immunodeficiency virus (HIV)-1 infection, decrease of telomere length is primarily found in CD8+ T cells, and not in CD4+ T cells. In this double-blind placebo-controlled study, we investigated the effect of granulocyte colony stimulating factor (G-CSF) treatment combined with highly active antiretroviral therapy (HAART) on mean telomere length in peripheral blood mononuclear cells (PBMC). The terminal restriction fragment (TRF) length showed no changes during G-CSF treatment although the number of lymphocytes increased significantly. The mean TRF length correlated positively (R = 0.552, P = 0.009) and negatively (R = -0.503, P = 0.02) to the proportion of CD4+ memory and naïve cells, respectively. Our data suggest that during G-CSF treatment lymphocytes are recruited by a combination of central and peripheral proliferation.

Adult↗

The effect of long-term treatment with granulocyte colony-stimulating factor on hematopoiesis in HIV-infected individuals.

This randomized, placebo-controlled trial examine the long-term effect of granulocyte colony-stimulating factor (G-CSF) on absolute numbers of CD34+ progenitor cells and progenitor cell function in human immunodeficiency virus (HIV)-infected patients. G-CSF (300 microg filgrastim) or placebo was given three times weekly for 12 weeks to 30 HIV-infected patients that had been treated with HAART for at least 24 weeks and not yet achieved CD4 counts above 350 CD4+ cells/microl. Blood samples were collected at weeks 0, 2, 4, 8, and 12, and again 12 weeks after termination of the G-CSF treatment. Significant increase in absolute numbers of circulating CD34+ cells was detected in the treatment group (P = 0.006). The function of progenitor cells was examined in vitro using a colony-forming unit (CFU) assay, and increase in the number of CFU/ml was detected (P = 0.005). In order to estimate the effect of G-CSF on in vivo function of progenitors the white-blood count was determined. Significant increase in white-blood count was found (P < 0.001), while hemoglobin and platelet count decreased (P = 0.001 and P = 0.013, respectively). Significant increase in the CD4 count occurred, but correlation between the numbers of progenitors and the CD4 count was not found. These data suggest that G-CSF mainly increases the number and differentiation of myeloid progenitors.

Anti-HIV Agents↗

Prognostic value of single measurements of beta-2-microglobulin, immunoglobulin A in HIV disease after controlling for CD4 lymphocyte counts and plasma HIV RNA levels.

The interrelationships between the CD4 lymphocyte count, plasma viral load [human immunodeficiency virus (HIV) RNA], beta-2-microglobulin (beta2-M) and immunoglobulin A (IgA) and the mortality risk was explored in 234 HIV-infected individuals (median CD4 count 230 cells/mm3, range 1-1,247). Product-moment correlation analysis was used to study the association between beta2-M, IgA and HIV RNA. A proportional hazards Cox model was used to estimate the relative hazard (RH) of death. Both beta2-M (r = 0.49, p < 0.0001) and IgA (r = 0.42, p < 0.0001) were positively correlated with HIV RNA. High beta2-M levels were associated with an increased risk of death in both univariate Cox analysis and after adjustment for HIV RNA, CD4 lymphocyte count and age [RH = 1.16 per 100 nmol/l higher beta2-M, 95% confidence interval (CI) 1.05-1.27]. Raised IgA levels were associated with shorter survival in individuals with a CD4 count above 50 cells/mm3 in univariate analysis as well as after adjusting for age and CD4 lymphocyte count (RH = 1.19 per 10 micromol/l higher IgA, 95% CI 1.01-1.39). However, this association was no longer significant after further adjusting for HIV RNA. In conclusion, beta2-M levels provided additional prognostic information for survival to the information obtained by CD4 count and HIV RNA levels, whereas serum IgA only was a weak prognostic marker in this fairly progressed cohort.

Adult↗

Granulocyte colony-stimulating factor increases CD4+ T cell counts of human immunodeficiency virus-infected patients receiving stable, highly active antiretroviral therapy: results from a randomized, placebo-controlled trial.

Thirty human immunodeficiency virus (HIV)-infected patients with CD4+ T cell counts <350 cells/mm3 who had received stable, highly active antiretroviral therapy (HAART) for at least 24 weeks were randomized to receive either placebo or granulocyte colony-stimulating factor (G-CSF; 0.3 mg/mL 3 times a week) for 12 weeks. Blood samples were collected at specified time points. G-CSF treatment enhanced the total lymphocyte count (P=.002) and increased CD3+ (P=.005), CD4+ (P=.03), and CD8+ (P=.004) T cell counts as well as numbers of CD3-CD16+CD56+ NK cells (P=.001). The increases in CD4+ and CD8+ cell counts resulted from increases in CD45RO+ memory T cells and cells expressing the CD38 activation marker. Lymphocyte proliferative responses to phytohemagglutinin and Candida antigen decreased, whereas NK cell activity and plasma HIV RNA did not change during G-CSF treatment. After 24 weeks, all immune parameters had returned to baseline values. This study suggests that G-CSF treatment of HIV-infected patients receiving stable HAART increases the concentration of CD4+, CD8+, and NK cells without inducing changes in the virus load.

Adult↗

Proliferative and cytotoxic capabilities of CD16+CD56- and CD16+/-CD56+ natural killer cells.

Natural killer (NK) cells can be divided into several subpopulations according to their expression of the surface antigens CD16 and CD56. The modest quantity of NK cells in the blood available for functional analysis has been a limitation in studies of NK cell subpopulations. In the present study, epinephrine infusion was used to induce lymphocytosis before immunomagnetic methods were applied to isolate CD16+/-CD56+ and CD16+CD56- CD3- NK cells. These subpopulations were compared according to their proliferative and cytotoxic capabilities in 10 human immunodeficiency virus (HIV)-infected individuals and 5 healthy controls. The CD16+CD56- NK cell subgroup had a higher proliferative capacity, whereas the CD16+/-CD56+ NK cell subgroup was mainly cytotoxic, and unaffected by HIV serostatus. This study thus suggests that NK cell phenotypes more strongly predict NK cell function than HIV serostatus. This assertion should be considered when studying NK cell function in subjects with a deviating composition of NK cells.

Adrenergic beta-Agonists↗

Epinephrine-induced mobilization of natural killer (NK) cells and NK-like T cells in HIV-infected patients.

HIV infection is known to cause changes in phenotype and function of natural killer (NK) cells. The aim of this study was to characterize the NK cells mobilized from peripheral reservoirs in human immunodeficiency virus (HIV)-infected patients and controls. Seventeen HIV-infected patients and eight age- and sex-matched controls received a 1-h epinephrine infusion. Epinephrine induced mobilization of high numbers of NK-like T cells with no difference between HIV-infected patients and controls. Interestingly, all subjects mobilized NK cells containing increased proportions of perforin, in particular the CD3(-)CD16(+)CD56(+) NK cell subset. The HIV-infected patients mobilized CD3(-)CD16(-)CD56(+) and CD3(-)CD16(+)CD56(+) NK cells to a lesser extent than did controls. In contrast, the HIV-infected patients mobilized relatively more CD3(-)CD16(+)CD56(-) NK cells independent of antiretroviral treatment. It is suggested that these cells represent an immature NK cell subpopulation possibly resulting from an impaired cytokine tissue environment in HIV-infected patients.

Adult↗

Immune function and phenotype before and after highly active antiretroviral therapy.

Immune functions represented by equal CD4 counts before and after highly active antiretroviral therapy (i.e., pre- and post-HAART) in the same HIV-infected patients, were examined. Twelve HIV-infected patients were included. Patients had equal CD4 counts pre- and post-HAART and were studied on average 30 months pre-HAART and 17 months post-HAART. Post-HAART, CD8+ T cells expressed greater amounts of CD28 (p < .02), smaller amounts of CD38 (p < .02), and a reduced proportion of CD4+CD28+ T cells expressed CD38+ (p < .01). Proliferation increased (p < 10) in lymphocyte cell cultures stimulated with pokeweed mitogens or Candida, and was correlated to expression of CD28 on T cells (p < .02). The proportion of CD3-CD16-CD56+ natural killer (NK) cells increased (p < .05) and CD3-CD16+CD56- NK cells declined (p < .01). Production of interferon-gamma increased (p < .10). The number of naive and memory T cells, the non-major histocompatibility complex (non-MHC)-restricted and HIV-specific MHC-restricted cytotoxicity and the production of macrophage inflammatory protein-1gamma were unchanged. The finding of increased expression of CD28, correlating to increased proliferation capacity, and diminished expression of CD38 on T cells, indicates that following long-term HAART, repopulation occurs with less activated cells with increased proliferative capacity. This finding may be of clinical importance in considering risk and vulnerability for progression of opportunistic infections post-HAART.

Anti-HIV Agents↗

Natural immunity and HIV disease progression.

OBJECTIVE: To investigate the clinical implications of impaired levels of the natural immunity mediated by natural killer (NK) cells and lymphokine activated killer (LAK) cells during infection with HIV-1. DESIGN: Data used were from 172 individuals with an estimated measure of NK cell activity and 146 with an estimated measure of LAK cell activity. Patients had active HIV infection at the time of enrolment in the study and have been followed-up prospectively for a median of 3.0 years. METHODS: The lytic activity of NK cells and LAK cells, the CD4 T lymphocyte count, and the concentration of CD16/CD56 NK cells were measured at enrolment. HIV RNA in plasma was measured retrospectively. Survival analysis was performed considering three main endpoints: CD4 cell counts below 100 x 10(6) cells/l, clinical AIDS, and death. RESULTS: In unadjusted analysis and after adjustment for age, CD4 T lymphocyte count and plasma HIV RNA at enrolment, low LAK cell activity was significantly associated with higher risk of progression to a CD4 T lymphocyte count < 100 x 10(6) cells/l (crude P = 0.001; adjusted P = 0.04) and to death (crude P = 0.0002; adjusted P = 0.02). Patients with low NK cell responsiveness to interferon-alpha tended to be at higher risk of death (crude P = 0.04; adjusted P = 0.13) whereas unstimulated NK cell activity and the concentration of NK cells were of no prognostic value for patients in this cohort. CONCLUSIONS: The present study suggests that low LAK cell activity and low NK cell responsiveness to interferon-alpha may be important in the pathogenesis of HIV infection.

CD4 Lymphocyte Count↗

Immunological changes in human immunodeficiency virus (HIV)-infected individuals during HIV-specific protease inhibitor treatment.

The present study examines the influence of effective anti-retroviral treatment on immune function, evaluated by a broad array of immunological tests. We followed 12 individuals infected with human immunodeficiency virus (HIV) for 6 months after initiation of combination anti-retroviral treatment including a protease inhibitor. Unstimulated and pokeweed mitogen (PWM)-, interleukin (IL)-2- and phytohaemagglutinin (PHA)-stimulated lymphocyte proliferative responses increased during follow-up reaching average levels from 1.3-fold (PHA) to 3.7-fold (PWM) above baseline values. The total CD4+ lymphocyte count increased mainly due to increases in numbers of CD4+ CD28+ and CD4+ CD45RO+ cells, whereas increases in numbers of CD4+ CD45RA+ cells contributed little to the increase in CD4+ cell count. The total cytotoxic T-cell (CTL) killing of autologous B cells infected with HIV-encoding recombinant Vaccinia virus was increased after 3-6 months, whereas the specific HIV-directed CTL activity and the concentration and lytic activity of natural killer (NK) cells were unchanged during follow-up. These results demonstrate that the initiation of a treatment including an HIV protease inhibitor is followed by an increase in lymphocyte proliferation and lymphocyte-mediated cytotoxicity. However, unchanged levels of specific HIV CTL and NK cell activity warn us that not all measures of immune function may respond simultaneously to anti-retroviral treatment.

Adult↗

Bulk culture levels of specific cytotoxic T-cell activity against HIV-1 proteins are not associated with risk of death.

The ability of cytotoxic T lymphocytes (CTL) to control and influence the outcome of human immunodeficiency virus (HIV) infection is not fully understood. The association between HIV-CTL activity and disease progression was evaluated prospectively in 36 HIV-1-infected individuals with a median follow-up of 3.0 years. HIV-CTL activity was measured in a 4 h Cr* release assay using autologous target cells expressing HIV-1 BRU isolate gene products (gp-120, gag, pol, nef) and a bulk culture of autologous effector cells. The CD4 count was measured at enrolment and plasma HIV RNA was measured retrospectively. The present study failed to support the hypothesis that HIV-CTL activity, as measured using the present method, is important in reducing the risk of death in HIV-infected individuals. However, using other approaches and methods could possibly yield other conclusions, and further prospective studies are needed to examine the relationship between CTL and disease progression.

Adult↗

The relative prognostic value of plasma HIV RNA levels and CD4 lymphocyte counts in advanced HIV infection.

OBJECTIVE: It has been suggested that the plasma HIV RNA level is a better predictor of AIDS and death than the CD4 lymphocyte count. We assessed whether the prognostic value of plasma virus levels was different according to the CD4 count. DESIGN: Prospective cohort study of HIV-infected patients followed for a median of 2.91 years (range, 0.02-4.54). SETTING: Department of Infectious Diseases at Rigshospitalet, Copenhagen, Denmark. PARTICIPANTS: A group of 255 HIV-infected individuals with an initial measurement of CD4 lymphocyte count and plasma HIV RNA. MAIN OUTCOME MEASURE: Survival time. RESULTS: The plasma HIV RNA (median 101410 copies/ml; range (range 200-7200000) and the CD4 lymphocyte count (median 250 cells x 10(6)/l; range 1-1247) were negatively correlated (Pearson r = -0.53; P < 0.00001). Of the 255 patients, 110 died during follow-up. Overall, a higher HIV RNA level was associated with increased risk of death, but the association was smaller in patients with lower CD4 lymphocyte counts (test for interaction P < 0.0001). In patients with CD4 count below 50 cells x 10(6)/l the association between HIV RNA and risk of death was not statistically significant (relative hazard per 10-fold higher HIV RNA level was 1.53; P = 0.11; adjusted for age and CD4 count) while that between the CD4 count and risk of death was highly significant (relative hazard per 50% lower CD4 count 1.38; P = 0.005; adjusted for age and HIV RNA level). CONCLUSIONS: Patients were relatively lightly treated with antiretroviral drugs both before and during this study. In this situation, it appears that the HIV RNA level has a relatively weak association with risk of death in patients with advanced HIV infection and that the CD4 lymphocyte count is probably more useful in assessing prognosis.

Adult↗

Production of beta-chemokines in human immunodeficiency virus (HIV) infection: evidence that high levels of macrophage inflammatory protein-1beta are associated with a decreased risk of HIV disease progression.

Macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, and RANTES production were measured by ELISA in whole blood that had been stimulated for 4.5 h with phytohemagglutinin. The blood was from 90 healthy human immunodeficiency virus (HIV)-negative controls and from 245 HIV-infected subjects who were followed for < or = 4.5 years. HIV-infected persons without AIDS had increased levels of MIP-1alpha, MIP-1beta, and RANTES (P < .01) compared with levels in controls. Subjects with AIDS, compared with controls, had decreased production levels of MIP-1beta (P < .0001) and similar levels of MIP-1alpha and RANTES. A high level of MIP-1beta production was associated with a decreased risk of progressing to AIDS or death, as determined by univariate analysis (P < .01) and adjusted for CD4 cell count and age (P = .07, P = .06, respectively). The findings suggest that the production level of beta-chemokine changes during HIV infection and that a high level of beta-chemokine production in peripheral blood lymphocytes may be associated with less rapid disease progression in HIV infection.

Acquired Immunodeficiency Syndrome↗

Low production of interferon gamma is related to disease progression in HIV infection: evidence from a cohort of 347 HIV-infected individuals.

A total of 347 HIV-seropositive individuals attending the Department of Infectious Diseases at Rigshospitalet in Copenhagen and 110 age- and sex-matched healthy controls not at risk for HIV infection were included in this study. Interferon gamma (IFN-gamma) production was measured in whole blood of 223 HIV-seropositive individuals (68 had developed AIDS at enrollment) and 99 healthy sex- and age-matched controls 4.5 hr after challenge with phytohemagglutinin. HIV-infected individuals for whom IFN-gamma production was measured were followed with a median follow-up time of 2.89 years (range, 0.02-4.54 years) from the date of enrollment. Survival analysis was performed considering three different end points: (1) a CD4 count below 100 cells/mm3, (2) an AIDS diagnosis defined according to the 1993 Centers for Disease Control definition, and (3) death. The production of IFN-gamma was highly increased in the blood of HIV-infected individuals without AIDS, but decreased in the blood of AIDS patients (both compared to controls). In the HIV-infected individuals, the total production of IFN-gamma was positively correlated with the number of CD8+ T lymphocytes and with the number of CD16+/CD56+ natural killer cells and negatively correlated with serum levels of beta2-microglobulin. Low levels of IFN-gamma production were associated with an increased risk of experiencing a CD4 count below 100 cells/m3 and death, analyzed in both univariate analysis and in multivariate analysis adjusting for CD4 counts and age. Thus, changes in production of IFN-gamma seem to be truly related to the risk for disease progression in HIV infection.

Acquired Immunodeficiency Syndrome↗