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Dive into the research topics where Göran Bratt is active.

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Featured researches published by Göran Bratt.


The Lancet | 1998

Cellular cytotoxic response induced by DNA vaccination in HIV-1-infected patients

Sandra A. Calarota; Göran Bratt; Siv Nordlund; Jorma Hinkula; Ann-Charlotte Leandersson; Eric Sandström; Britta Wahren

BACKGROUND DNA vaccination is known to generate immune responses against HIV-1 in animal models. We aimed to assess the efficacy of DNA vaccination in induction of immune responses in HIV-1-infected human beings. METHODS Nine symptom-free HIV-1-infected patients were immunised with DNA constructs encoding the nef, rev, or tat regulatory genes of HIV-1. The patients were selected for having no or low antibody reactivities to these antigens. HIV-1-specific cytotoxic T-lymphocytes (CTLs), precursor frequencies, and antigen-specific proliferative responses were measured before, during, and after three immunisations over 6 months. FINDINGS Cellular immune reactivities against the HIV-1 regulatory proteins were absent or low before DNA immunisation. DNA vaccination induced detectable memory cells in all patients and specific cytotoxicity in eight patients. CTLs were MHC-class-I restricted and mainly of CD8+ origin. In three patients the cellular activity was transient, decreasing after an initial response. INTERPRETATION DNA immunisation with HIV-1 genes can induce specific cellular responses in human beings with no apparent side-effects. It is theoretically possible that HIV-1-specific cytotoxic responses to regulatory proteins could lead to infected cells being eliminated before they have released new viral particles. However, it is possible that the patients we selected responded less than would non-selected or non-infected individuals. The small number of patients presented here does not allow generalisation of our findings.


The Journal of Infectious Diseases | 2008

Broad Immunogenicity of a Multigene, Multiclade HIV-1 DNA Vaccine Boosted with Heterologous HIV-1 Recombinant Modified Vaccinia Virus Ankara

Eric Sandström; Charlotta Nilsson; Bo Hejdeman; Andreas Bråve; Göran Bratt; Merlin L. Robb; Josephine H. Cox; Thomas C. VanCott; Mary Marovich; Richard Stout; Said Aboud; Muhammad Bakari; Kisali Pallangyo; Karl Ljungberg; Bernard Moss; Patricia L. Earl; Nelson L. Michael; Deborah C. Birx; Fred Mhalu; Britta Wahren; Gunnel Biberfeld; Hiv Immunogenicity Study

BACKGROUND A human immunodeficiency virus (HIV) vaccine that limits disease and transmission is urgently needed. This clinical trial evaluated the safety and immunogenicity of an HIV vaccine that combines a plasmid-DNA priming vaccine and a modified vaccinia virus Ankara (MVA) boosting vaccine. METHODS Forty healthy volunteers were injected with DNA plasmids containing gp160 of HIV-1 subtypes A, B, and C; rev B; p17/p24 gag A and B, and RTmut B by use of a needle-free injection system. The vaccine was administered intradermally or intramuscularly, with or without recombinant granulocyte macrophage colony-stimulating factor, and boosted with a heterologous MVA containing env, gag, and pol of CRF01A_E. Immune responses were monitored with HIV-specific interferon (IFN)-gamma and interleukin (IL)-2 ELISpot and lymphoproliferative assays (LPAs). RESULTS Vaccine-related adverse events were mild and tolerable. After receipt of the DNA priming vaccine, 11 (30%) of 37 vaccinees had HIV-specific IFN-gamma responses. After receipt of the MVA boosting vaccine, ELISpot assays showed that 34 (92%) of 37 vaccinees had HIV-specific IFN-gamma responses, 32 (86%) to Gag and 24 (65%) to Env. IFN-gamma production was detected in both the CD8(+) T cell compartment (5 of 9 selected vaccinees) and the CD4(+) T cell compartment (9 of 9). ELISpot results showed that 25 (68%) of 37 vaccinees had a positive IL-2 response and 35 (92%) of 38 had a positive LPA response. Of 38 subjects, a total of 37 (97%) were responders. One milligram of HIV-1 DNA administered intradermally was as effective as 4 mg administered intramuscularly in priming for the MVA boosting vaccine. CONCLUSION This HIV-DNA priming-MVA boosting approach is safe and highly immunogenic. TRIALS REGISTRATION International Standard Randomised Controlled Trial number: ISRCTN32604572 .


PLOS ONE | 2010

Dynamics of HIV-1 Quasispecies during Antiviral Treatment Dissected Using Ultra-Deep Pyrosequencing

Charlotte Hedskog; Mattias Mild; Johanna Jernberg; Ellen Sherwood; Göran Bratt; Thomas Leitner; Joakim Lundeberg; Björn Andersson; Jan Albert

Background Ultra-deep pyrosequencing (UDPS) allows identification of rare HIV-1 variants and minority drug resistance mutations, which are not detectable by standard sequencing. Principal Findings Here, UDPS was used to analyze the dynamics of HIV-1 genetic variation in reverse transcriptase (RT) (amino acids 180–220) in six individuals consecutively sampled before, during and after failing 3TC and AZT containing antiretroviral treatment. Optimized UDPS protocols and bioinformatic software were developed to generate, clean and analyze the data. The data cleaning strategy reduced the error rate of UDPS to an average of 0.05%, which is lower than previously reported. Consequently, the cut-off for detection of resistance mutations was very low. A median of 16,016 (range 2,406–35,401) sequence reads were obtained per sample, which allowed detection and quantification of minority resistance mutations at amino acid position 181, 184, 188, 190, 210, 215 and 219 in RT. In four of five pre-treatment samples low levels (0.07–0.09%) of the M184I mutation were observed. Other resistance mutations, except T215A and T215I were below the detection limit. During treatment failure, M184V replaced M184I and dominated the population in combination with T215Y, while wild-type variants were rarely detected. Resistant virus disappeared rapidly after treatment interruption and was undetectable as early as after 3 months. In most patients, drug resistant variants were replaced by wild-type variants identical to those present before treatment, suggesting rebound from latent reservoirs. Conclusions With this highly sensitive UDPS protocol preexisting drug resistance was infrequently observed; only M184I, T215A and T215I were detected at very low levels. Similarly, drug resistant variants in plasma quickly decreased to undetectable levels after treatment interruption. The study gives important insights into the dynamics of the HIV-1 quasispecies and is of relevance for future research and clinical use of the UDPS technology.


Thrombosis Research | 1986

Low molecular weight heparin (KABI 2165, Fragmin): pharmacokinetics after intravenous and subcutaneous administration in human volunteers

Göran Bratt; Eva Törnebohm; L. Widlund; Dieter Lockner

The pharmacokinetics of a low molecular weight heparin (LMWH) with a mean mw of 4000-6000 D (KABI 2165, Fragmin) was studied in 6 healthy volunteers after intravenous (iv) and subcutaneous (sc) administration of 120 U (anti FXa)/kg. The half-life in plasma of the anti FXa activity after iv injection was 119 +/- 17 min, the volume of distribution (Vd) 3.4 +/- 0.5 1 and the total clearence 20.5 +/- 2.5 ml/min. The maximal anti FXa activity determined 3 min after iv bolus injection amounted to 2.2 +/- 0.3 U (anti FXa)/ml with a corresponding increase of the APTT from 31 +/- 7 sec to 113 +/- 35 sec. The elimination of the anti FXa activity was a monoexponential first order process. After sc administration the plasma half-life of the anti FXa activity was longer than after iv injection, 228 +/- 40 min, corresponding to the absorption rate thus found to be the rate limiting step. After sc administration the peak was reached after 4 hours (0.6 +/- 0.1 U (anti FXa)/ml; APTT increase 5 sec). The bioavailability after sc injection was calculated to be 87 +/- 6%. As a consequence of the high bioavailability and long T1/2 of the anti FXa activity, Fragmin administered sc seems to induce adequate levels of heparin-like activity making this regimen worth further investigation as an alternative for the treatment of deep venous thrombosis.


AIDS | 1999

BK virus as the cause of meningoencephalitis, retinitis and nephritis in a patient with AIDS

Göran Bratt; Hammarin Al; Grandien M; Hedquist Bg; Nennesmo I; Sundelin B; Seregard S

BACKGROUND The two widely spread human polyomaviruses, BK virus (BKV) and JC virus (JCV) establish latency in the urinary tract, and can be reactivated in AIDS. JCV might cause progressive multifocal leucoencephalopathy, but although up to 60% of AIDS patients excrete BKV in the urine there have been few reports of BKV-related renal and/or neurological disease in AIDS. OBJECTIVE To report on an AIDS patient with progressive renal and neurological symptoms involving the retina. DESIGN Case report. SETTING Venhälsan, Söder Hospital, Stockholm, Sweden. METHODS The brain, eye tissue, cerebrospinal fluid, urine and peripheral blood mononuclear cells were analysed by nested PCR for polyoma-virus DNA. Macroscopical and microscopical examination were performed of the kidney and brain post mortem. Immunohistochemical stainings for the two BKV proteins, the VP1 and the agnoprotein, were performed on autopsy material and virus infected tissue culture cells. RESULTS BKV could be demonstrated in the brain, cerebrospinal fluid, eye tissues, kidneys and peripheral blood mononuclear cells. CONCLUSION During 6 years, approximately 400 cerebrospinal fluid samples from immunosuppressed individuals with neurological symptoms have been investigated by PCR for the presence of polyomaviruses. BKV DNA has, so far, only been found in the case reported here. Although reports of BKV infections in the nervous system are rare, there is now evidence for its occurrence in immunocompromised patients and the diagnosis should be considered in such patients with neurological symptoms and signs of renal disease. The diagnosis is simple to verify and is important to establish.


Journal of Acquired Immune Deficiency Syndromes | 2002

Hypofibrinolytic state in HIV-1-infected patients treated with protease inhibitor-containing highly active antiretroviral therapy

Kristina Koppel; Göran Bratt; Sam Schulman; Håkan Bylund; Eric Sandström

Summary: Decreased insulin sensitivity, hyperlipidemia, and body fat changes are considered as risk factors for coronary heart disease (CHD). A clustering of such factors (metabolic syndrome [MSDR]) exponentially increases the risk. Impaired fibrinolysis and increased coagulation are additional independent risk factors for CHD. We studied the effects of protease inhibitor (PI)‐containing highly active antiretroviral therapy (HAART) on metabolic and hemostatic parameters in 363 HIV‐infected individuals, of whom 266 were receiving PI‐containing HAART and 97 were treatment naive. The fasting plasma levels of insulin, glucose, triglycerides, cholesterol, high‐density lipoprotein cholesterol, low‐density lipoprotein cholesterol, plasminogen activator inhibitor type 1 (PAI‐1), and fibrinogen were evaluated together with the areas of visceral adipose tissue and the visceral adipose tissue/subcutaneous adipose tissue area ratio. The levels of insulin, triglycerides, cholesterol, and low‐density lipoprotein cholesterol; visceral adipose tissue area; low‐density lipoprotein/high‐density lipoprotein ratio; and visceral adipose tissue/subcutaneous adipose tissue area ratio were significantly increased in patients receiving PI‐containing HAART compared with treatment‐naive patients. The levels of PAI‐1 and fibrinogen were significantly higher in patients receiving PI‐containing HAART. PAI‐1 levels were higher in individuals with MSDR but also in patients without MSDR who were receiving PI‐containing HAART. PAI‐1 was independently correlated to use of PI‐containing HAART, triglyceride level, insulin level, and body mass index (p < .001). These findings suggest that patients receiving PI‐containing HAART have decreased fibrinolysis and increased coagulability, which may thus represent additional risk factors for cardiovascular disease in this patient group.


AIDS | 2006

A nonsense mutation (428G-->A) in the fucosyltransferase FUT2 gene affects the progression of HIV-1 infection.

Elin Kindberg; Bo Hejdeman; Göran Bratt; Britta Wahren; Bertil Lindblom; Jorma Hinkula; Lennart Svensson

Background:The human FUT2 gene encodes the α(1,2)fucosyltransferase that determines secretor status. Homozygous for the nonsense mutation are called non-secretors and are unable to express histo-blood group antigens in secretions and on mucosal surfaces. In this study we have investigated the importance of the FUT2 fucosyltransferase activity on the progress of HIV-1 infection. Methods:Swedish blood donors (n = 276), 15 long-term non-progressors (LTNP) and 19 progressors were genotyped with respect to the nonsense mutation 428G→A in the FUT2 gene. In addition 265/276 blood donors and 19 progressors with rapid or expected progression rate were Δ32 CCR5 genotyped. Results:Of 276 blood donors 218 (79%) were found to be secretor positive (se+), either homozygous (se+/+) wild type (30%) or heterozygous (se+/−) (49%) and 58 (21%) were homozygous non-secretors (se−/−). Five LTNP (33%) were found to be secretor-positive (se+/+, se+/−) and 10 (67%) se−/−. Of the 19 individuals with normal HIV-1 progression 15 (79 %) were found to be secretor positive and four (21%) were non-secretors. No frequency differences were found in the Δ32 CCR5 allele among the groups studied. Conclusion:Strong association (P < 0.001) was observed between the nonsense mutation 428G→A in the FUT2 gene and a slow disease progression of HIV-1 infection.


eLife | 2015

Population genomics of intrapatient HIV-1 evolution

Fabio Zanini; Johanna Brodin; Lina Thebo; Christa Lanz; Göran Bratt; Jan Albert; Richard A. Neher

Many microbial populations rapidly adapt to changing environments with multiple variants competing for survival. To quantify such complex evolutionary dynamics in vivo, time resolved and genome wide data including rare variants are essential. We performed whole-genome deep sequencing of HIV-1 populations in 9 untreated patients, with 6-12 longitudinal samples per patient spanning 5-8 years of infection. The data can be accessed and explored via an interactive web application. We show that patterns of minor diversity are reproducible between patients and mirror global HIV-1 diversity, suggesting a universal landscape of fitness costs that control diversity. Reversions towards the ancestral HIV-1 sequence are observed throughout infection and account for almost one third of all sequence changes. Reversion rates depend strongly on conservation. Frequent recombination limits linkage disequilibrium to about 100bp in most of the genome, but strong hitch-hiking due to short range linkage limits diversity. DOI: http://dx.doi.org/10.7554/eLife.11282.001


PLOS ONE | 2012

Low Prevalence of Transmitted Drug Resistance in Patients Newly Diagnosed with HIV-1 Infection in Sweden 2003–2010

Annika C. Karlsson; Per Björkman; Göran Bratt; Håkan Ekvall; Magnus Gisslén; Anders Sönnerborg; Mattias Mild; Jan Albert

Transmitted drug resistance (TDR) is a clinical and epidemiological problem because it may contribute to failure of antiretroviral treatment. The prevalence of TDR varies geographically, and its prevalence in Sweden during the last decade has not been reported. Plasma samples from 1,463 patients newly diagnosed with HIV-1 infection between 2003 and 2010, representing 44% of all patients diagnosed in Sweden during this period, were analyzed using the WHO 2009 list of mutations for surveillance of TDR. Maximum likelihood phylogenetic analyses were used to determine genetic subtype and to investigate the relatedness of the sequences. Eighty-two patients showed evidence of TDR, representing a prevalence of 5.6% (95% CI: 4.5%–6.9%) without any significant time trends or differences between patients infected in Sweden or abroad. Multivariable logistic regression showed that TDR was positively associated with men who have sex with men (MSM) and subtype B infection and negatively associated with CD4 cell counts. Among patients with TDR, 54 (68%) had single resistance mutations, whereas five patients had multi-drug resistant HIV-1. Phylogenetic analyses identified nine significantly supported clusters involving 29 of the patients with TDR, including 23 of 42 (55%) of the patients with TDR acquired in Sweden. One cluster contained 18 viruses with a M41L resistance mutation, which had spread among MSM in Stockholm over a period of at least 16 years (1994–2010). Another cluster, which contained the five multidrug resistant viruses, also involved MSM from Stockholm. The prevalence of TDR in Sweden 2003–2010 was lower than in many other European countries. TDR was concentrated among MSM, where clustering of TDR strains was observed, which highlights the need for continued and improved measures for targeted interventions.


International Journal of Std & Aids | 2000

Serum lipid levels associated with increased risk for cardiovascular disease is associated with highly active antiretroviral therapy (HAART) in HIV-1 infection

Kristina Koppel; Göran Bratt; Mats Eriksson; Eric Sandström

The long-term effects of fat metabolism, storage and utilization in HIV-1 infected patients on highly active antiretroviral therapy (HAART) including a protease inhibitor are profound and cause increasing concern. The main importance of these lipid/metabolic disorders lies in their assumed contribution to an increased risk of coronary heart disease (CHD). In the general population increased levels of lipoprotein(a) [Lp(a)] constitute an independent risk factor for CHD by itself as well as in combination with increased levels of cholesterol and low density lipoprotein (LDL)-cholesterol, respectively. Two hundred and fifty-six patients with 27 ± 7 months HAART and 84 treatment-naive HIV-1 positive patients were screened for cardiovascular risk factors. The subjective perception of fat wasting and/or accumulation in different sites of the body, which was possible to evaluate in 235 patients on HAART and 73 treatment-naive patients, the levels of plasma triglycerides (TG), cholesterol, LDL and high-density lipoproteins (HDL)-cholesterol, LDL/HDL ratio and Lp(a) were measured. Of the patients on HAART, 42% (98/235) reported abnormal fat distribution as compared with 4% (3/73) of the treatment-naive patients (P < 0.0001). The levels of TG, cholesterol and LDL-cholesterol, but not HDL-cholesterol or Lp(a) were higher (P < 0.0001) in the HAART group as compared with the naive group. Very high Lp(a) levels (>700 mg/l) were more common among HAART patients as compared with naive, 14% (36/256) vs 2% (2/83); P = 0.0022. The Lp(a) levels correlated to the levels of LDL-cholesterol, but not to total cholesterol, HDL-cholesterol or TG, and did not differ between patients with and without subjective perception of abnormal fat distribution. A significant number of the HAART patients had very high levels of Lp(a) and various combinations of increased lipid values associated with considerably increased risk for CHD. The elevation of Lp(a) did not relate to any other clinical or laboratory parameter than to LDL-cholesterol.

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Lars Eriksson

Karolinska University Hospital

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