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T L Katzenstein

Publications and source records attributed to T L Katzenstein.

At least 19 recordsLinked to original sources

Plasma levels of intact and cleaved urokinase receptor decrease in HIV-1-infected patients initiating highly active antiretroviral therapy.

Elevated blood levels of soluble urokinase receptor (suPAR) measured by ELISA decrease in human immunodeficiency virus-1 (HIV-1)-infected patients initiating highly active antiretroviral therapy (HAART). As the suPAR ELISA measures both three- and two-domain suPAR [suPAR(I-III), suPAR(II-III)] and suPAR(I-III)-ligand complexes, the amount by which the individual suPAR forms (suPAR(I-III), suPAR(II-III) and one-domain suPAR [suPAR(I)]) decrease in plasma in HIV-1-infected patients initiating HAART is unknown. Consequently, the objective of this study was to investigate HAART-induced changes in the individual plasma suPAR forms in HIV-1-infected patients. Plasma suPAR was measured by three time-resolved fluorescence immunoassays detecting suPAR(I-III), suPAR(I-III) + suPAR(II-III) and suPAR(I) in 29 treatment-naïve HIV-1-infected patients followed annually for 5 years after initiation of HAART and in 20 age- and gender-matched healthy individuals. In addition, plasma levels of the following inflammatory markers were also investigated: soluble tumour necrosis factor receptor (sTNFr)-II, TNF-alpha, interleukins (IL)-10, IL-6, IL-4, IL-2 and interferon (IFN)-gamma. In HIV-1-infected patients, plasma suPAR(I-III), suPAR(II-III) and suPAR(I) decreased within the first treatment year (all P < 0.05) and suPAR(I-III) and suPAR(II-III) remained above normal throughout follow-up (both P < 0.05). Plasma sTNFrII, IL-6, IFN-gamma and IL-10 also decreased during HAART (all P < 0.05). In HIV-1-infected patients, sTNFrII correlated with all suPAR forms before (all P < 0.01) and after 5 years HAART (all P < 0.001), whereas sTNFrII and suPAR did not correlate in healthy individuals. Intact and cleaved plasma suPAR decreased in HIV-1-infected patients initiating HAART but remained above normal. The positive correlation with sTNFrII suggests that the individual plasma suPAR forms are linked to immune activation in HIV-1 infection.

Adult↗

2B4 expression on natural killer cells increases in HIV-1 infected patients followed prospectively during highly active antiretroviral therapy.

Human immunodeficiency virus (HIV)-1 infection influences natural killer (NK) cell expression of inhibitory NK receptors and activating natural cytotoxicity receptors. It is unknown whether expression of the co-stimulatory NK cell receptor 2B4 (CD244) on NK cells and CD3+ CD8+ cells are affected by highly active antiretroviral therapy (HAART), low-level viraemia, proviral-DNA or immune activation in HIV-1 infected patients. A total of 101 HAART-treated HIV-1 infected patients with < or = 200 HIV-RNA copies/ml were followed prospectively for 24 months. HIV-RNA was investigated 3-monthly and 2B4 expression on CD3- CD16+ NK cells and CD3+ CD8+ cells, proviral-DNA and plasma soluble tumour necrosis factor receptor (sTNFr)-II were investigated 6-monthly. For comparison, 2B4 expression was investigated in 20 healthy individuals. The concentration of 2B4+ NK cells was initially reduced in HIV-1 infected patients (P < 0.001) but increased to a normal level during the 24 months' follow-up. The concentration of CD3+ CD8+ 2B4+ cells in HIV-1 infected patients was normal and did not change during follow-up. The relative fluorescence intensity (RFI) of 2B4 increased on both NK cells and CD3+ CD8+ cells during follow-up (both P < 0.001). Higher levels of proviral-DNA carrying cells and plasma sTNFrII were associated with reductions in the concentration of 2B4+ NK cells (all P < 0.05). HIV-RNA had no effect on 2B4 expression on NK cells or CD3+ CD8+ cells. These findings demonstrate that the concentration of 2B4+ NK cells normalizes during long-term HAART in HIV-1 infected patients. The finding that proviral-DNA and sTNFrII were associated negatively with the concentration of 2B4+ NK cells suggests that immune activation in HIV-1 infected patients receiving HAART influences the target cell recognition by NK cells.

Adult↗

Hepatitis A outbreak among MSM linked to casual sex and gay saunas in Copenhagen, Denmark.

During an outbreak of hepatitis A predominantly among men who have sex with men (MSM) in Copenhagen, Denmark, in 2004, we did a case-control study to determine risk factors for infection. A case was an MSM >17 years, living in Copenhagen, with IgM positive hepatitis A infection diagnosed between June and August 2004, and without a household contact with a hepatitis A case before onset of illness. Controls were selected at the Copenhagen Pride Festival. The study included 18 cases and 64 controls. Sixteen of 18 cases and 36/63 controls had sex with casual partners (ORMH 5.6, 95% CI 1.2-26.9). Eleven of 18 cases and 14/62 controls had sex in gay saunas (ORMH 4.2, 95% CI 1.5-11.5). Sex at private homes appeared to be protective (ORMH 0.2, 95% CI 0.1-0.7). Casual sex including sex in gay saunas was an important risk factor for the spread of HAV among MSM in Copenhagen. The results are in accordance with findings in other European outbreaks. As the general immunity to hepatitis A decreases and the outbreak potential increases, we recommend health education and hepatitis A vaccination to all MSM not living in monogamous relationships, especially if they visit gay saunas or other places with frequent partner change. To stop spread of hepatitis A among MSM in Europe, a European consensus on prevention and control measures may be required.

Adult↗

Resistance profiles and adherence at primary virological failure in three different highly active antiretroviral therapy regimens: analysis of failure rates in a randomized study.

OBJECTIVES: To investigate the interplay between resistance and adherence in the virological failure of three fundamentally different highly active antiretroviral therapy (HAART) regimens. METHODS: We retrospectively identified 56 verified primary virological failures (viral load >400 HIV-1 RNA copies/mL) among 293 patients randomized to two nucleoside reverse transcriptase inhibitors (NRTIs)+ritonavir+saquinavir (RS-arm) (n=115), two NRTIs+nevirapine+nelfinavir (NN-arm) (n=118), or abacavir+stavudine+didanosine (ASD-arm) (n=60) followed up for a median of 90 weeks. Data on adherence were collected from patient files, and genotyping was performed on plasma samples collected at time of failure. RESULTS: Treatment interruption or poor adherence was mainly caused by side effects and accounted for 74% of failures, and was associated with absence of resistance mutations. In the 30 failing patients not switched from randomized treatment, we found resistance in two of 12 patients in the RS-arm (M184 V only), four of six patients in the NN-arm [all four had non-nucleoside reverse transcriptase inhibitor (NNRTI) mutations], and seven of 12 patients in the ASD-arm (NRTI mutations only). Two adherent patients on randomized treatment failed in the RS-arm, none in the NN-arm, and six in the ASD-arm. CONCLUSIONS: Primary virological failure was caused mainly by treatment interruption. No primary protease inhibitor (PI) mutations were found in patients failing on boosted saquinavir, whereas resistance to NNRTIs and NRTIs was prevalent in several patients failing on regimens based on these medications.

Adult↗

Virological and immunological profiles among patients with undetectable viral load followed prospectively for 24 months.

OBJECTIVE: To quantify HIV-RNA in plasma, in lymphoid tissue and proviral DNA in peripheral blood mononuclear cells and to relate these to immunological markers among patients with plasma viral load counts of </= 200 HIV-RNA copies/mL. METHODS: A prospective study of one hundred and three patients was undertaken with an inclusion criteria of plasma viral load of </= 200 copies/mL. The patients had advanced HIV infection; 25% had developed AIDS. Patients were seen every 6 months for a period of 2 years. RESULTS: The median plasma viral load was < 20 copies/mL with no increase during follow-up. Thirty-one per cent had plasma viral load of </= 20 copies/mL at all visits, 44% had >/= 1 measurement with 21-200 and 25% had >/= 1 sample with plasma HIV-RNA > 200 copies/mL. Lymphoid tissue viral load was low at enrolment and declined further during follow-up. Baseline HIV-DNA and immunoglobulin (IgA) differed significantly between the plasma viral load rebound groups (P < 0.05). CONCLUSION: In this cohort, selected solely on the basis of having a plasma viral load of </= 200 copies/mL, we found stable or declining viral loads in the measured compartments during 2 years of follow-up. Baseline HIV-DNA and IgA levels were higher among patients with less complete virological suppression relative to patients with persistently undetectable plasma HIV-RNA. Hence, a high cellular level of HIV-DNA and high plasma IgA may predict subsequent development of low-grade viraemia.

Adult↗

Drug resistance mutations and outcome of second-line treatment in patients with first-line protease inhibitor failure on nelfinavir-containing HAART.

OBJECTIVES: To determine resistance mutations emerging in HIV-1-infected patients experiencing their first protease inhibitor (PI)-failure on nelfinavir-containing highly active antiretroviral therapy (HAART), and to assess virological response to rescue regimens. METHODS: Plasma HIV-1 RNA from 24 patients failing nelfinavir-containing HAART was sequenced. Failure was defined as two consecutive measurements of viral load > 400 HIV-1 RNA copies/mL. Patients with previous failure on other PIs were excluded. Data on response to second-line treatment was extracted from patient files. RESULTS: At failure primary protease mutations were found in 14 patients (58%). Ten patients had D30N (38%), five patients had L90M (19%), two patients had V82A/F (8%) and two patients had M46I/L (8%). Two patients had both D30N and L90M. Pronounced increases of secondary protease mutations were seen at codon 88 (Delta: 33%), codon 36 (Delta: 30%) and codon 71 (Delta: 17%). Of eight patients with N88D, seven also harboured D30N (P < 0.01). Polymorphisms at codon 63 were detected at baseline in all patients who developed primary resistance mutations at failure (P < 0.01). On rescue regimens, 78% achieved viral loads below limit of detection (BLD). The presence of primary protease mutations was not associated with a higher risk of failure on second-line treatment. CONCLUSION: In patients failing nelfinavir-containing HAART, D30N was detected frequently and L90M occasionally. A pronounced accumulation of the secondary protease mutations N88D, M36I, and A71V/T was found, and D30N was strongly associated with N88D. A high proportion of patients became undetectable on second-line treatment and the presence of primary resistance mutations did not negatively affect the outcome of rescue regimens.

Antiretroviral Therapy, Highly Active↗

Clinical lipoatrophy in HIV-1 patients on HAART is not associated with increased abdominal girth, hyperlipidaemia or glucose intolerance.

OBJECTIVE: To compare information on body fat changes from questionnaire and clinical examination and to study lipoatrophy in HIV-1 patients on highly active antiretroviral therapy (HAART). METHODS: The study was cross-sectional within a randomized trial. One hundred and sixty-eight male HIV-1 patients were examined by questionnaire and clinical examination. Clinical lipoatrophy was studied and defined as fat wasting in the face, legs and/or arms. Fasting blood samples reflecting lipid and glucose metabolism were taken and the role of indinavir, ritonavir (RTV) and RTV/saquinavir (SQV) on lipoatrophy was investigated. RESULTS: After a median of 17 months on HAART, concordance rates between information on changes in body fat from questionnaire and clinical examination were significant and varied from 70 to 96%. With a positive criteria of lipoatrophy in both assessments, 14% of patients had lipoatrophy. These patients had lower weight (P = 0.0007), weight loss from baseline (P = 0.003), lower circumferences at all measurements (P < 0.01), lower plasma triglycerides and low-density lipoprotein (LDL) (P < 0.05) and longer treatment with stavudine (P = 0.0009). Homeostasis model assessment (HOMA) estimates for insulin resistance and beta-cell function were comparable. Plasma cholesterol, triglycerides and very low-density lipoprotein (VLDL) were higher in patients receiving RTV or RTV/SQV (P < 0.03). CONCLUSION: Questionnaire and clinical assessment provide concordant information on changes in body fat. Lipoatrophic patients on HAART with neither increase in abdominal circumference, nor hyperlipidaemia nor glucose intolerance may have side-effects to protease inhibitor treatment, to nucleoside reverse transcriptase inhibitor treatment (stavudine) or suffer from a drug-independent condition.

Adult↗

Effects of CCR5-Delta32, CCR2-64I, and SDF-1 3'A alleles on HIV-1 disease progression: An international meta-analysis of individual-patient data.

BACKGROUND: Studies relating certain chemokine and chemokine receptor gene alleles with the outcome of HIV-1 infection have yielded inconsistent results. OBJECTIVE: To examine postulated associations of genetic alleles with HIV-1 disease progression. DESIGN: Meta-analysis of individual-patient data. SETTING: 19 prospective cohort studies and case-control studies from the United States, Europe, and Australia. PATIENTS: Patients with HIV-1 infection who were of European or African descent. MEASUREMENTS: Time to AIDS, death, and death after AIDS and HIV-1 RNA level at study entry or soon after seroconversion. Data were combined with fixed-effects and random-effects models. RESULTS: Both the CCR5-Delta32 and CCR2-64I alleles were associated with a decreased risk for progression to AIDS (relative hazard among seroconverters, 0.74 and 0.76, respectively; P = 0.01 for both), a decreased risk for death (relative hazard among seroconverters, 0.64 and 0.74; P < 0.05 for both), and lower HIV-1 RNA levels after seroconversion (difference, -0.18 log(10) copies/mL and -0.14 log(10) copies/mL; P < 0.05 for both). Having the CCR5-Delta32 or CCR2-64I allele had no clear protective effect on the risk for death after development of AIDS. The results were consistent between seroconverters and seroprevalent patients. In contrast, SDF-1 3'A homozygotes showed no decreased risk for AIDS (relative hazard for seroconverters and seroprevalent patients, 0.99 and 1.03, respectively), death (relative hazard, 0.97 and 1.00), or death after development of AIDS (relative hazard, 0.81 and 0.97; P > 0.5 for all). CONCLUSIONS: The CCR5-Delta32 and CCR2-64I alleles had a strong protective effect on progression of HIV-1 infection, but SDF-1 3'A homozygosity carried no such protection.

Acquired Immunodeficiency Syndrome↗

Low body weight and type of protease inhibitor predict discontinuation and treatment-limiting adverse drug reactions among HIV-infected patients starting a protease inhibitor regimen: consistent results from a randomized trial and an observational cohort.

OBJECTIVES: To assess predictors for discontinuation and treatment-limiting adverse drug reactions (TLADR) among patients starting their first protease inhibitor (PI). METHODS: Data on patients starting a PI regimen (indinavir, ritonavir, ritonavir/saquinavir and saquinavir hard gel) in a randomized trial (RAS, n = 318) and an observational cohort (OBC, n = 505) were used to document reasons for discontinuation and TLADR. Risk factors for discontinuation of the initial PI/developing TLADR were assessed in Cox models. RESULTS: A total of 43 (RAS) and 48% (OBC) discontinued the initial PI therapy within less than 2 years. In both populations TLADR were the most common reason for discontinuation. The incidence of TLADR in RAS was: 8.5 (indinavir), 66.0 (ritonavir), 15.6 (saquinavir hard gel) per 100 person-years of follow-up (P < 0.001). Body weight and type of PI initiated were independent risk factors for treatment discontinuation and TLADR in both groups. In OBC, the risk of developing TLADR increased by 12% per 5 kg lower body weight when starting the PI regimen [the relative hazard (RH) was 1.12 (95% confidence interval: 1.05-1.19) per 5 kg lighter], and starting ritonavir was associated with a three- to sixfold higher risk of TLADR relative to other PI regimens. Very similar results were documented in RAS [RH for body weight was 1.18 (1.07-1.29)]. CONCLUSIONS: Nearly half of the patients stopped treatment with the initial PI, most commonly as a result of adverse drug reactions. Low body weight and initiation of ritonavir relative to other PIs were associated with an increased risk of TLADRs. Very consistent results were found in a randomized trial and an observational cohort.

Adult↗

Comparison of P-triglyceride levels among patients with human immunodeficiency virus on randomized treatment with ritonavir, indinavir or ritonavir/saquinavir.

This study compared the alterations in p-triglyceride (PT) in 111 protease inhibitor (PI)-naive patients on randomized treatment with either indinavir (800 mg 3 times daily), ritonavir (600 mg twice daily) or ritonavir/saquinavir (400 mg each twice daily) and 2 nucleoside reverse transcriptase inhibitors (NRTIs). PT (non-fasting) was measured at regular intervals until week 48. PT levels were evaluated in relation to PI regime, CD4 cell count and prior NRTI experience. The effect on PT levels of changing PI regime was analysed. For 24 patients fasting and non-fasting PT values were correlated. In the ritonavir-containing arms PT levels increased significantly (median PT at baseline: 1.80 mmol/l; week 36: 2.3 mmol/l; p < 0.001). In the indinavir arm no significant rise in PT levels was observed. Comparing the PI arms at week 48 showed significantly higher levels of PT in the ritonavir-containing arms than in the indinavir arm (p < 0.001). There was a high correlation between fasting and non-fasting PT values (p < 0.001, p = 0.88). A significant decline in PT values when changing PI treatment was observed (n = 13, p = 0.016). Ritonavir-containing regimens caused a rapid and sustained elevation of PT values, while indinavir did not significantly affect PT levels.

Anti-HIV Agents↗

Adverse effect of the CCR5 promoter -2459A allele on HIV-1 disease progression.

HIV positive individuals heterozygous for a 32 basepair deletion in the CCR5 encoding gene (CCR5 Delta32) have a reduced number of CCR5 receptors on the cell surface and a slower progression towards AIDS and death. Other human polymorphisms, such as the CCR2 64I and the CCR5 promoter -2459 A/G transition that has been discovered recently, have also been shown to influence HIV progression. Since genetic linkages make these polymorphisms interdependent variables, the aim of the present study was to isolate and evaluate the effect on HIV disease progression for each of these mutations independently. Genotypes were determined in 119 individuals enrolled in the Copenhagen AIDS Cohort. When including the concurrent effects of the CCR5 Delta32 and CCR2 64I mutations, homozygous carriers of the CCR5 promoter -2459A allele had a significantly faster progression towards death than heterozygous A/G individuals (P = 0.03), whereas this adverse effect was not significant when comparing A/A and G/G individuals. However, independent analysis revealed a significant adverse effect of the CCR5 promoter -2459A allele. Homozygous carriers of the -2459A allele that lack the protective effects of the CCR5 Delta32 and CCR2 64I mutations were found to have a median survival of 6.0 years, whereas carriers of the -2459G allele had a median survival of 9.4 years (P < 0.01).

Alleles↗

The danish protease inhibitor study: a randomized study comparing the virological efficacy of 3 protease inhibitor-containing regimens for the treatment of human immunodeficiency virus type 1 infection.

The Danish Protease Inhibitor (PI) Study has enrolled 318 human immunodeficiency virus (HIV)-infected, PI-naive patients for the purpose of comparing 3 PI-containing regimens for the treatment of HIV infection. The regimens include 2 nucleoside analogues in combination with indinavir (Idr), ritonavir (Rtv), or Rtv and saquinavir (Rtv/Sqv). Similar percentages of patients in the 3 study arms achieved reduced levels (</=20 copies/mL) of HIV RNA. In the area under the curve minus baseline analyses, a better response was found in the Rtv/Sqv arm than in the Rtv arm. No difference was found when comparing Rtv/Sqv with Idr and Rtv with Idr. Patients in the 3 arms had comparable increases in CD4 cell counts. At 72 weeks of follow-up, there was no statistical difference between arms for the primary study end point (</=20 HIV RNA copies/mL); however, some of the additional analyses indicated an advantage for the Rtv/Sqv arm, especially when compared with the Rtv arm.

Adolescent↗

Predictors of virological success and ensuing failure in HIV-positive patients starting highly active antiretroviral therapy in Europe: results from the EuroSIDA study.

BACKGROUND: Predictors of virological response to highly active antiretroviral therapy (HAART) have never been systematically evaluated in a large continental multicenter cohort of unselected human immunodeficiency virus (HIV)-infected people. OBJECTIVE: To determine the factors related to achieving and maintaining undetectable plasma HIV-1 RNA levels among HIV-1-infected patients first starting protease inhibitor- or nonnucleoside retrotranscriptase inhibitor-containing HAART in Europe. DESIGN: Prospective multicenter cohort study. SETTING: Fifty-two clinical centers in 17 European countries included in the EuroSIDA Study Group, from August 1996 to April 1999. PATIENTS: A total of 1469 HIV-positive patients first starting HAART recruited from an unselected cohort of more than 7300 HIV-positive patients. MAIN OUTCOME MEASURE: Detection of factors related to virological success after first starting HAART (baseline) and ensuing failure by standard survival techniques, including Kaplan-Meier techniques and Cox proportional hazards models. All analyses were intention to treat. RESULTS: Most patients (80%) achieved plasma HIV-1 RNA levels of less than 500 copies/mL during follow-up (60.4% at 6 months from the onset of HAART). Patients with higher baseline HIV-1 RNA levels (relative hazard [RH], 0.76 per log higher; 95% confidence interval [CI], 0.69-0.84; P<.001) and those taking saquinavir mesylate hard gel as a single protease inhibitor (RH, 0.62; 95% CI, 0.47-0.82; P<.001) were less likely to reach undetectable HIV-1 RNA levels. Conversely, higher CD4+ lymphocyte counts (RH per 50% higher, 1.09; 95% CI, 1.02-1.16; P = .008) and the initiation of 3 or more new antiretroviral drugs (RH, 1.29; 95% CI, 1.03-1.61; P = .02) were independent predictors of higher success. Once success was achieved, HIV-1 RNA levels rebounded in more than one third of all patients during follow-up (24% at 6 months). Antiretroviral-naive patients (RH, 0.50; 95% CI, 0.29-0.87; P = .01), older patients (RH, 0.86 per year older; 95% CI, 0.75-0.99; P = .04), and those starting a protease inhibitor other than saquinavir hard gel (RH, 0.66; 95% CI, 0.44-0.98; P = .04) were at decreased hazard for virological failure. Higher baseline HIV-1 RNA level (RH, 1.18 per log higher; 95% CI, 0.99-1.40; P = .06) and a longer time to achieve virological success (RH per 12 months, 1.53; 95% CI, 0.99-2.38; P = .06) were marginally significant predictors of a decreased hazard of ensuing virological failure. CONCLUSIONS: HAART is associated with a favorable virological response if started when the baseline HIV-1 RNA level is low, if at least 2 new nucleoside retrotranscriptase inhibitors are added, and if standard doses of saquinavir hard gel capsule are avoided as a single protease inhibitor. Older patients are more likely to achieve virological success. Thereafter, the higher durability of virological response is predicted by an antiretroviral-naive status and by the use of specific regimens. Lower baseline HIV-1 RNA levels and rapid maximal viral suppression seem to be other important factors in the durability of virological response.

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↗

Genotypic and phenotypic nevirapine resistance correlates with virological failure during salvage therapy including abacavir and nevirapine.

OBJECTIVE: To study the development of resistance during 8 weeks of salvage therapy with abacavir and nevirapine in combination with other reverse transcriptase inhibitors (RTIs) and protease inhibitors (PIs). METHODS: Samples obtained at baseline and after 8 weeks of therapy from 16 heavily pretreated patients were analysed for genotypic and phenotypic resistance. Genotypic resistance was analysed in cell-associated DNA and plasma HIV-RNA using direct sequencing. Phenotypic resistance was analysed in a PBMC-based assay and in a recombinant virus assay. Plasma viral load was measured at baseline and after 2, 4 and 8 weeks of therapy. RESULTS: The majority of patients was genotypically and phenotypically resistant to lamivudine, abacavir, zidovudine and PIs, whereas 50% of the patients showed resistance to nevirapine at baseline in at least one of the methods used. After 8 weeks of salvage therapy, no additional development of resistance against nucleoside reverse transcriptase inhibitors and PIs could be detected. However, the amount of patients resistant to nevirapine increased to 83%. When the patients were divided into two groups according to baseline resistance against nevirapine, a significantly higher transient reduction in viral load was observed in patients with nevirapine-sensitive HIV at baseline compared to patients with resistant HIV at baseline. CONCLUSION: The transient effect of salvage therapy including abacavir and nevirapine was due to the effect of nevirapine. The lack of effect of abacavir was most likely due to cross-resistance between abacavir and lamivudine/zidovudine used in previous treatment.

Anti-HIV Agents↗