Distribution of subtypes of pol gene in HIV-1 epidemic strains in Guangxi Zhuang Autonomous Region, 2010- 2012 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the distribution and proportion of subtypes of pol gene in HIV-1 epidemic strains in Guangxi Autonomous Region.</p><p><b>METHODS</b>152 HIV-1 patients were enrolled from 11 cities in Guangxi Autonomous Region from 2010 to 2012 by convenient sampling. Inclusion criterias were listed as the fdlowing: HIV-1 infection was confirmed by Western blot, HIV-1 viral load >1 000 copies/ml, > 18 year-old, and without any serious illnesses. 5 ml of peripheral blood samples were obtained from each patient. The viral RNA was isolated from plasma and used for amplification of full-length pol gene by nested RT-PCR. The amplified products were sequenced. After editing and modification, all sequences were characterized for preliminary subtyping by genotyping and confirmed with phylogenetic tree constructed by MEGA 5.03 software. The recombinant identification of 2 unknown recombinant strains was determined by RIP and jpHMM at GOBICS.</p><p><b>RESULTS</b>Among 152 patients, 137 full-length pol genes were successfully amplified and 127 HIV-1 subtypes were identified. The distribution and proportion of subtypes was summarized as the following 71 cases of CRF01_AE, accounting for 55.9% (71/127), 38 CRF08_BC, 29.9% (38/127), 13 CRF07_BC, 10.2% (13/127), and 3 B (B'), 2.4% (3/127), 2 unknown recombinant strains, 1.6% (2/127). In 11 cites of Guangxi Autonomous Region, subtype CRF01_AE was the dominant strain. Among heterosexual transmitted patients and drug abusers, the proportions of subtype CRF01_AE were 67.4% (58/86) and 34.1% (14/41), respectively. There was a significance different in the distribution of CRF01_AE in different routes of transmission (χ(2)=15.07, P<0.001). In age 21- 35, age 36- 60 and age>60 groups, the proportions of CRF01_AE was 43.6% (17/39), 57.6% (38/66), 77.3% (17/22), and CRF08_BC was 43.6% (17/39), 28.8% (19/66), 9.1% (2/22), respectively, the difference in proportions was significant(χ(2)=8.48, P= 0.014). The patterns of two unknown recombinant strains were found to be CRF01_AE/B (B') and CRF01_AE/C/B(B'), respectively.</p><p><b>CONCLUSION</b>CRF01_AE was the dominant HIV-1 subtype in Guangxi Autonomous Region from 2010 to 2012, with heterosexual transmission as its main spreading route. The two unknown recombinant strains in Guangxi Autonomous Region were reconstructed by subtype CRF01_AE and CRF_BC.</p>

Drug-resistance characteristics of CRF01_AE and CRF07_BC subtypes of HIV-1 strains in Sichuan province / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the drug resistance of HIV patients to the HIV-1 CRF01_AE and CRF07_BC strains in Sichuan province during 2010 to 2013.</p><p><b>METHODS</b>1.5 ml of plasma were collected from AIDS patients who had been receiving anti-retroviral treatment for over 6 months but still had a HIV-1 virus load of over 1 000 copies/ml from January 1, 2010 to December 31, 2013 in Sichuan province. Genetic analysis of the HIV-1 pol gene was performed using self-established method, and patients with a positive drug-resistant HIV-1 pol gene mutation were included. HIV-1 poly gene was successfully sequenced for a total of 1 213 patients. Drug resistance of different HIV-1 strains was compared with χ2 test or Fisher exact test.</p><p><b>RESULTS</b>558 cases (46.0%) of the 1 213 successfully sequenced patients were infected by HIV-1-strains with drug-resistant mutations, including 327 cases (58.6%) infected by CRF01_AE strain, 126 (22.6%) by CRF07_BC strain, 46 (8.2%) by CRF08_BC strain, 33 (5.9%) by B strain, 4 (0.7%) by C strain, 1 (0.2%) by CRF02_AG strain, and 21 (3.8%) by unidentified strains. Drug-resistant mutation analysis revealed that L33, F116, L74, Q151, and T69 resistance mutations occurred only in the CRF01_AE strain, while A71, K43, and Q58 resistance mutations occurred only in the CRF07_BC strain; in nuclear nucleoside reverse transcriptase inhibitors (NRTIs) and non nucleoside reverse transcriptase inhibitors (NNRTIs), CRF01_AE subtype strains showed highly resistant rate were higher than CRF07_BC, CRF08_BC and B subtype strains, with the differences were statistically significant (P<0.05).</p><p><b>CONCLUSION</b>The drug-resistant HIV-1 strains in Sichuan mainly included the CRF01_AE and CRF07_BC strains, which had different resistance mutations.</p>

HIV-1 subtype diversity and transmission clusters among men having sex with men who recently got HIV-l infection, in Zhejiang province / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the HIV-1 subtype diversity and transmission characteristics in men having sex with men (MSM) in Zhejiang province.</p><p><b>METHODS</b>A total of 233 newly diagnosed as HIV-1 positive patients in 2011 were screened out by BED capture enzyme immunoassay (BED-CEIA). Among them, 107 eligible subjects were enrolled for further molecular epidemiological study. Viral RNA was extracted from plasma samples and followed by reverse transcription PCR and nested PCR for amplification of pol gene fragments, sequencing, and bioinformatics analysis.</p><p><b>RESULTS</b>There were no statistically significant differences regarding the social demographic distribution between the subjects under study and those recently infected MSM population. The rate of success for sequence acquisition was 94.4% (101/107). The highest proportion of subtype was CRF01_AE (62.4%), followed by CRF07_BC (31.7%) and with three cases of subtype B, one case of CRF55_01B and two cases of unique recombinant form (CRF01_AE/B and CRF01_AE/CRF07_BC). The phylogenetic trees were mainly divided into CRF01_AE cluster 1, cluster 2 and CRF07_BC cluster 3. The strains located in Hangzhou were diffused in the branches of phylogenetic tree. 10 transmission clusters were found, in which 80% involved two or more regions and 90% was associated with patients residing in Hangzhou. Three surveillance drug resistance mutations (M46I, T215S and G190A) were found in three samples (each sample harbored only one resistance mutation). The overall rate of transmitted drug resistance (TDR) was 2.97%.</p><p><b>CONCLUSION</b>The increasing complexity of HIV was noticed in MSM in Zhejiang province. However, the prevalence of TDR was low. Cross-regional HIV transmission in MSM was common, which inferred from the study. Hangzhou might play a central regional role in the intra-provincial spread of HIV, to form an interwoven complex network in the MSM population.</p>

Analysis on HIV-1 genetics and threshold of drug resistance in Dehong prefecture of Yunnan province in 2013 / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the HIV-1 genotypes and transmitted drug resistance (TDR) in Dehong prefecture of Yunnan province in 2013.</p><p><b>METHODS</b>Referring to the guidelines for HIV drug resistance threshold survey (HIVDR-TS), 54 plasma samples of recently reported HIV-infected individuals, aged between 16 and 25 years, were collected in Dehong prefecture from January to August 2013. Genotyping of partial pol gene was performed by using reverse transcriptional PCR. HIV-1 genotype. Prevalent levels of HIV-1 drug resistance transmission were analyzed.</p><p><b>RESULTS</b>Forty-eight plasma samples were successfully sequenced and analyzed. Among them, 45.8% were Chinese and the rest 54.2% were all Burmese. Based on pol sequences, identified HIV genotypes included subtype C (41.7%), URF (31.3%), CRF01_AE (12.5%), CRF07_BC (10.4%), CRF08_BC (2.1%) and subtype B (2.1%), C subtype appeared dominated in Chinese while URF was dominated in Burmese. One drug resistant mutation to non-nucleoside reverse transcriptase inhibitors (NNRTIs) was detected in one sequence from Burmese. Based on the statistical method of HIVDR-TS, the prevalence of transmitted HIV-1 drug resistance was adjusted as < 5%.</p><p><b>CONCLUSION</b>Diverse HIV-1 genotypes were found in this study, and the current HIV-1 drug resistant strains transmission was catalogued as at low prevalence level, in Dehong. To prevent the increase of the prevalence of transmitted HIV-1 drug resistance, standard treatment and scientific management for people living with HIV/AIDS should be strictly followed. Meanwhile, relevant surveillance, including drug resistance surveillance should also be performed among cross-border migrant population.</p>

The efficacy of antiviral therapy and drug resistance analysis among HIV/AIDS patients with heroin addiction in Guangxi Zhuang Autonomous Region / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the impact of heroin for antiviral treatment, drug resistance, mutation types and frequency in HIV/AIDS patients in Guangxi Zhuang Autonomous Region.</p><p><b>METHODS</b>HIV/AIDS patients were recruited in Methadone Maintenance Treatment Clinics, HIV/AIDS Clinic and HIV Voluntary Counseling and Testing Center Liuzhou and Baise city from April 2008 to October 2009. The patients were grouped by the situation of antiviral treatment and use of heroin. A total of 435 HIV/AIDS patients were recruited, among which 108 cases in antiviral treatment and heroin group, 93 cases in antiviral treatment and never using drug group, 105 cases in no antiviral treatment and using heroin group, 129 cases in no antiviral treatment and never using drug group. The effect of antiviral treatment was evaluated by questionnaire survey, viral load measurement and CD4(+) T lymphocyte count. HIV-1 RNA from plasma was extracted, and then the pol genes were amplified and sequenced. The sequences were analyzed for HIV-1 genotype drug-resistance.</p><p><b>RESULTS</b>For the patients who received antiviral treatment, the viral load in heroin group was higher than that in never using drug group (lg (2.61 ± 1.24) vs lg (2.08 ± 0.80), t = 3.54, P < 0.05) , and the percentage of viral load lower than 1 000 copies/ml in heroin group was significantly less than that in never using drug group (63.9% vs 86.0%,χ(2) = 12.76, P < 0.05). For the patients who received antiviral treatment, the difference has no significance in CD4(+) T lymphocyte count between heroin group and never using drug group ((337.92 ± 181.66) vs (326.14 ± 254.98), t = 0.38, P = 0.703). For the patients who didn't receive antiviral treatment, the difference also has no significance in CD4(+) T lymphocyte count between heroin group and never using drug group ((373.73 ± 155.97) vs (337.53 ± 209.26), t = 1.47, P = 0.143). For the patients who received antiviral treatment, there was no difference in the percentage of the CD4(+) T lymphocyte count more than 350/ml between heroin group and never using drug group (48.1% vs 43.0%, χ(2) = 0.53, P = 0.466). 319 HIV-1 pol gene sequences were obtained. Among the patients who received antiviral treatment, the mutation frequency of M184V/I, T215Y/F, L210W and T69N/S in heroin abuser group were significantly higher than that in never using drug group (14.9% (11/74) vs 4.4% (3/68), 12.2% (9/74) vs 1.5% (1/68), 12.2% (9/74) vs 1.5% (1/68) and 10.8% (8/74) vs 1.5% (1/68) respectively) (P < 0.05).</p><p><b>CONCLUSION</b>Using heroin may promote HIV replication, reducing the virological response to antiviral treatment and increasing the frequencies of drug resistance loci among HIV/AIDS patients.Heroin rehabilitation may benefit from the antiviral treatment and obtain better antiviral effect.</p>

Distribution of human immunodeficiency virus type 1 subtypes in the state of Amazonas, Brazil, and subtype C identification

Few studies have reported the molecular epidemiological characterization of HIV-1 in the Northern region of Brazil. The present study reports the molecular and epidemiological characterization of 31 HIV-1 isolates from blood donors from the State of Amazonas who donated blood between April 2006 and March 2007. Serum/plasma samples from all donors were screened for HIV antibodies by ELISA and the results confirmed by Western blot analysis. Genomic DNA was extracted from the buffy coat using the Super Quik-Gene-DNA Isolation kit. Nested PCR was performed on the env, gag, and pol regions of HIV-1 using the Gene Amp PCR System 9700. Sequencing reactions were performed using the inner PCR primers and the DYEnamic™ ET Dye Terminator Kit, and phylogenetic analysis was performed using the gag, pol, and env gene sequences. We collected samples from 31 blood donors who tested positive for HIV-1 in confirmatory experiments. The male:female ratio of blood donors was 3.4:1, and the mean age was 32.4 years (range: 19 to 61 years). Phylogenetic analysis showed that subtype B is the most prevalent among Northern Brazilian HIV-1-seropositive blood donors. One HIV-1 subtype C and one circulating recombinant form (CRF_BF) of HIV-1 were identified in the State of Amazonas. This is the first study showing the occurrence of a possible "homogenous" subtype C in this region of Brazil. This finding could contribute to a better characterization of the HIV-1 strains that circulate in the country.

Immunogenicities and comparison of DNA vaccines encoding pol genes derived from B`/C and A/E recombinant HIV-1 strains / 中华预防医学杂志

<p><b>OBJECTIVE</b>To construct and compare the immunogenicities of DNA vaccines expressing pol genes derived from B`/C and A/E recombinant subtypes of HIV-1 in China.</p><p><b>METHODS</b>Two DNA vaccines were constructed by inserting the codon optimized pol genes derived from B'/C and A/E subtypes of HIV-1 into mammalian expression vector pSV1.0. In vitro expression efficiencies of the two DNA vaccines were determined by Western blotting and their immunogenicities were compared by i.m. immunizing female BALB/c mice. After immunization, mice splenocytes were isolated sterilely and IFN-γ based enzyme linked immunospot assay (ELISPOT) was employed to read out the specific T cell immunity.</p><p><b>RESULTS</b>The constructed DNA vaccines were validated by restriction enzyme digestion and DNA sequencing. Western blotting result showed both of the two DNA vaccines could be expressed at appreciable levels in vitro. Under the stimulation of Consensus B Pol peptide pools, specific T cell frequency elicited by pSVAE-Pol was (636±178) SFCs/10(6) splenocytes; specific T cell frequency elicited by pSVCN-Pol was (468±265)SFCs/10(6) splenocytes (P=0.412). Under the stimulation of HIV-1 AE2f Pol peptide pools, specific T cell frequency elicited by pSVAE-Pol was (1378±611) SFCs/10(6) splenocytes; specific T cell frequency elicited by pSVCN-Pol was (713±61) SFCs/10(6) splenocytes (P=0.134). Further analysis suggested pSVAE-Pol induced specific T cell responses mainly focused on Pol 1 peptide pool, while, in addition to induce Pol 1 specific T cell responses, pSVCN-Pol could also elicit T cell responses against consensus B Pol 2 peptide pool.</p><p><b>CONCLUSION</b>Although pSVAE-Pol was more immunogenic, pSVCN-Pol could induce T cell responses against broader epitope spectrum. Rational vaccine design may need combine them together.</p>

Clinical evaluation of an in-house human immunodeficiency virus (HIV) genotyping assay for the detection of drug resistance mutations in HIV-1 infected patients in Singapore

<p><b>INTRODUCTION</b>Human immunodeficiency virus type 1 (HIV-1) genotyping resistance test (GRT) is essential for monitoring HIV-1 drug resistance mutations (DRMs). High cost and HIV-1 genetic variability are challenges to assay availability in Singapore. An in-house Sanger sequencing-based GRT method was developed at the Communicable Disease Centre (CDC), Singapore's HIV national treatment reference centre for both subtype B and non-subtype B HIV-1.</p><p><b>MATERIALS AND METHODS</b>The in-house GRT sequenced the fi rst 99 codons of protease (PR) and 244 codons of reverse transcriptase (RT) in the pol gene. The results were compared with the Food and Drug Administration (FDA)-approved ViroSeq™ HIV-1 Genotyping System.</p><p><b>RESULTS</b>Subtype assignment for the 46 samples were as follows: 31 (67.4%) CRF01_AE, 14 (30.5%) subtype B and 1 (2.1%) subtype C. All 46 samples had viral load of ≥500 copies/mL, and were successfully amplified by the in-house primer sets. Compared to the ViroSeq™ test, our in-house assay showed drug-resistance conferring codon concordance of 99.9% at PR and 98.9% at RT, and partial concordance of 0.1% at PR and 1.1% at RT. No discordant result was observed.</p><p><b>CONCLUSION</b>The assay successfully identified DRMs in both subtype AE and B, making it suitable for the efficient treatment monitoring in genetically diverse population. At less than half of the running cost compared to the ViroSeq™ assay, the broadly sensitive in-house assay could serve as a useful addition to the currently limited HIV genotyping assay options for resource-limited settings, thereby enhancing the DRM surveillance and monitoring in the region.</p>

Genotyping and variability of HIV-1 in 26 cases of paid blood donors / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To analyze the genome mutations of HIV-1 gag, pol and env genes from HIV-infected paid blood donors in rural central China.</p><p><b>METHODS</b>DNA was extracted from peripheral blood mononuclear cells, gag (p17-p24), pol (PR-RT), env (C2-V5) genes were amplified by nested polymerase chain reaction (PCR), purified products were sequenced, and sequence data was analyzed by MEGA5.0 soft wares.</p><p><b>RESULTS</b>Twenty-three samples were subtype B, two samples were recombinant of subtype B and subtype C, one sample was recombinant of subtype CRF01_AE and subtype B. PI major resistance mutations were not found in the PR region. M184V, K101E and G190A were detected in the RT region, respectively.</p><p><b>CONCLUSION</b>Subtype B was the major HIV circulating genetic forms in this area. Most strains were sensitive to high active anti-retroviral therapy (HARRT). 91.7% V3 loop tip motifs of X4-tropic strains was GPGR. It showed that GPGR might be associated with accelerate disease progression to AIDS.</p>

Prevalence and patterns of HIV transmitted drug resistance in Guatemala / Prevalencia y patrones de farmacorresistencia transmitida del VIH en Guatemala

Objective. To assess human immunodeficiency virus (HIV) diversity and the prevalence of transmitted drug resistance (TDR) in Guatemala. Methods. One hundred forty-five antiretroviral treatment-naïve patients referred to the Roosevelt Hospital in Guatemala City were enrolled from October 2010 to March 2011. Plasma HIV pol sequences were obtained and TDR was assessed with the Stanford algorithm and the World Health Organization (WHO) TDR surveillance mutation list. Results. HIV subtype B was highly prevalent in Guatemala (96.6%, 140/145), and a 2.8% (4/145) prevalence of BF1 recombinants and 0.7% (1/145) prevalence of subtype C viruses were found. TDR prevalence for the study period was 8.3% (12/145) with the Stanford database algorithm (score > 15) and the WHO TDR surveillance mutation list. Most TDR cases were associated with non-nucleoside reverse transcriptase inhibitors (NNRTIs) (83.3%, 10/12); a low prevalence of nucleoside reverse transcriptase inhibitors and protease inhibitors was observed in the cohort (< 1% for both families). Low selection of antiretroviral drug resistance mutations was found, except for NNRTI-associated mutations. Major NNRTI mutations such as K101E, K103N, and E138K showed higher frequencies than expected in ART-naïve populations. Higher literacy was associated with a greater risk of TDR (odds ratio 4.14, P = 0.0264). Conclusions. This study represents one of the first efforts to describe HIV diversity and TDR prevalence and trends in Guatemala. TDR prevalence in Guatemala was at the intermediate level. Most TDR cases were associated with NNRTIs. Further and continuous TDR surveillance is necessary to gain more in-depth knowledge about TDR spread and trends in Guatemala and to optimize treatment outcomes in the country.

Objetivo. Evaluar la diversidad del virus de la inmunodeficiencia humana (VIH) y la prevalencia de la farmacorresistencia transmitida en Guatemala. Métodos. Entre octubre del 2010 y marzo del 2011 se incluyeron en el estudio 145 pacientes no tratados anteriormente con antirretrovirales, derivados al Hospital Roosevelt en la Ciudad de Guatemala. Se obtuvieron las secuencias pol a partir del VIH plasmático y se evaluó la farmacorresistencia transmitida con el algoritmo de Stanford y la lista de mutaciones para la vigilancia de la farmacorresistencia transmitida de la Organización Mundial de la Salud (OMS). Resultados. El subtipo B del VIH fue sumamente prevalente en Guatemala (96,6%, 140/145), y se encontró una prevalencia de formas recombinantes BF1 de 2,8% (4/145) y una prevalencia del subtipo C del virus de 0,7% (1/145). La prevalencia de la farmacorresistencia transmitida durante el período de estudio fue de 8,3% (12/145) según el algoritmo de la base de datos de Stanford (puntuación > 15) y la lista de mutaciones para la vigilancia de la farmacorresistencia transmitida de la OMS. En la mayoría de los casos, la farmacorresistencia transmitida se asoció con los inhibidores de la transcriptasa inversa no análogos de nucleósidos (ITINN) (83,3%, 10/12); en la cohorte se observó una baja prevalencia asociada con los inhibidores de la transcriptasa inversa análogos de nucleósidos y con los inhibidores de la proteasa (< 1% para ambas familias de fármacos). Se encontró una baja selección de mutaciones causantes de farmacorresistencia debidas a los antirretrovirales, excepto en las mutaciones asociadas a los ITINN. Las mutaciones importantes relacionadas con los ITINN, como K101E, K103N y E138K, mostraron frecuencias más elevadas que las esperadas en las poblaciones vírgenes de tratamiento antirretroviral. En las personas con un nivel de escolaridad más elevado se encontró un mayor riesgo de farmacorresistencia transmitida (razón de posibilidades 4,14; P = 0,0264). Conclusiones. Este estudio representa uno de los primeros intentos de describir la diversidad del VIH, y la prevalencia de la farmacorresistencia transmitida y sus tendencias en Guatemala. La prevalencia de la farmacorresistencia transmitida en Guatemala presentó un nivel intermedio y en la mayoría de los casos se asoció con los ITINN. Se necesita una vigilancia más intensa y sostenida de la farmacorresistencia transmitida para conocer más exhaustivamente su grado de diseminación y sus tendencias en Guatemala, al igual que para optimizar los resultados del tratamiento antirretroviral en el país.

HIV transmitted drug resistance in adult and pediatric populations in Panama / Farmacorresistencia transmitida del VIH en poblaciones adultas y pediátricas en Panamá

Objetivo. Investigar la prevalencia de farmacorresistencia transmitida del VIH en adultos en Panamá mediante un estudio del umbral modificado de la Organización Mundial de la Salud (OMS) e investigar las tasas de resistencia inicial en lactantesseropositivos para el VIH en Panamá.Métodos. En el Instituto Conmemorativo Gorgas, en 47 adultos seropositivos al VIH se efectuó la genotipificación de las mutaciones asociadas con la farmacorresistencia transmitida en los genes de la transcriptasa inversa y la proteasa del VIH-1, según las directrices del estudio umbral de la OMS, modificadas para incluir a las personas ≤ 26 años de edad. Las tasas de prevalencia de las mutaciones farmacorresistentes contra tres clases de fármacos antirretroviral —inhibidores de la transcriptasa inversaanálogos de nucleósidos, inhibidores de la transcriptasa inversa no análogos de nucleósidos e inhibidores de la proteasa— se clasificaron en bajas (< 5,0%), moderadas (5,0%–15,0%) o altas (> 15,0%). También se llevó a cabo genotipificación y se calcularonlas tasas de prevalencia de las mutaciones causantes de farmacorresistencia en 25 lactantes.Resultados. En los adultos de Panamá la farmacorresistencia transmitida fue moderada: 6 de 47 adultos seropositivos para el VIH presentaron una o más mutacionesasociadas con farmacorresistencia transmitida. Las mutaciones farmacorresitentes de transmisión horizontal fueron moderadas para los inhibidores de la transcriptasainversa análogos de nucleósidos y los inhibidores de la transcriptasa inversa no análogos de nucleósidos, y bajas para los inhibidores de la proteasa. En Panamá la transmisiónvertical del VIH ha disminuido en el período 2002–2007, pero la prevalenciade la farmacorresistencia del VIH transmitida por vía vertical es moderada (12,0%) y está surgiendo como un problema debido a la cobertura antirretroviral incompletadurante el embarazo...

Objective. To investigate the prevalence of transmitted drug-resistant HIV among adults in Panama by using a modified World Health Organization Threshold Survey (WHO-TS) and to investigate rates of initial resistance among HIV-positive infants in Panama.Methods. At the Gorgas Memorial Institute, 47 HIV-positive adults were genotyped for mutations associated with transmitted drug resistance (TDR) in the reverse transcriptase andprotease genes of HIV-1, according to WHO-TS guidelines, modified to include patients ≤ 26 years old. Prevalence rates for drug-resistance mutations against three classes of antiretroviraldrugs—nucleoside analog reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), and protease inhibitors—were calculated as low (< 5.0%), moderate (5.0%–15.0%), and high (> 15.0%). Twenty-five infant patients were also genotyped and prevalence rates for drug-resistance mutations were calculated. Results. TDR among Panamanian adults was moderate: 6 of 47 HIV-positive adultsshowed one or more mutations associated with TDR. Horizontal TDR mutations were moderate for NRTIs and NNRTIs and low for protease inhibitors. Vertical transmission of HIV inPanama has decreased for 2002–2007, but vertical HIV TDR prevalence is moderate (12.0%) and is emerging as a problem due to incomplete antiretroviral coverage in pregnancy. Conclusions. The prevalence of HIV TDR indicated by this study, combined with knownrates of HIV infection in Panama, suggests more extensive surveys are needed to identify risk factors associated with transmission of HIV drug resistance. Specific WHO-TS guidelines for monitoring vertical transmission of drug-resistant HIV should be established.

Variability in HIV-1 partial genomic sequences in Costa Rican patients: analysis with different bioinformatics tools / Variabilidad de secuencias genómicas parciales del VIH-1 en pacientes costarricenses: análisis con diferentes herramientas bioinformáticas

OBJECTIVE: To estimate subtype and genomic variability in the HIV pol gene of Costa Rican patients by using different bioinformatics tools and to use this information to establish new policies to better manage these patients. METHODS: A total of 113 pol sequences available from Costa Rican patients under highly active antiretroviral therapy were analyzed by using the Genotyping, REGA, Stanford, and MEGA programs. The pol sequences came from 77 virologic failures (VF) and 36 basal samples (BS). Of the 77 VF, 22 also were sequenced in the env region. RESULTS: No major differences were found among the variables studied. However, there was a tendency for more variability in VF patients with a high baseline viral load. In the pol gene, 75 percent-83 percent of BS and 66 percent-75 percent of VF samples were pure B subtype by Genotyping and REGA, respectively. The other samples presented variations related mainly to circulating recombinant form CRF12 by genotyping or to CRF17 or -29 by phylogenetic analysis or a new possible BD recombinant with all programs. In the Stanford program, all variable samples showed a subtype B with high polymorphism. The variability in the env sequences was lower than that in the pol region. CONCLUSION: The B subtype is predominant in Costa Rican HIV-positive patients. There is high variability within sequences with potential recombination between B and F or D subtypes. The BD recombinant has not been previously reported. This high variability is likely the result of possible recombinant events, nonadherence to antiretroviral therapy, sexual intercourse without protection, and many sexual partners. Similar studies should be done in other countries in the Region, in particular in those places with extensive immigration, in order to decrease the possibility of virus variability as well as the cost of antiretroviral therapy.

OBJETIVOS: Determinar el subtipo y la variabilidad genómica del gen pol del VIH de pacientes costarricenses mediante diferentes herramientas bioinformáticas y el uso de esta información para establecer nuevas políticas para mejorar el diagnóstico y el tratamiento de estos pacientes. MÉTODOS: Se analizaron 113 secuencias del gen pol de pacientes costarricenses bajo tratamiento antirretrovírico de gran actividad mediante cuatro programas: Genotyping, REGA, Stanford y MEGA. Las secuencias pol analizadas provenían de 77 casos considerados fracasos virológicos (FV) y 36 muestras iniciales (MI). También se secuenció la región env de 22 de los 77 FV. RESULTADOS: No se encontraron diferencias importantes entre las variables estudiadas. No obstante, se observó una tendencia a una mayor variabilidad en los pacientes FV que tenían una elevada carga viral inicial. Con respecto al gen pol, 77-83 por ciento de las MI y 66-75 por ciento de las muestras de los FV eran del subtipo B puro según Genotyping y REGA, respectivamente. Las otras muestras presentaron variaciones relacionadas principalmente con la forma recombinante en circulación CRF-12 según Genotyping, con la CRF-17 o la CRF-29 según el análisis filogenético, o una nueva posible forma recombinante BD según todos los programas. Con el programa Stanford, todas las muestras variables reflejaron un subtipo B con elevado polimorfismo. La variabilidad de la secuencia env fue menor que la de la región pol. CONCLUSIONES: El subtipo B fue el predominante en los pacientes positivos al VIH en Costa Rica. Existe una alta variabilidad en las secuencias con una posible recombinación entre los subtipos B, y F o D. La forma recombinante BD no se había notificado antes. Esta elevada variabilidad parece ser el resultado de posibles eventos de recombinación, la falta de adhesión al tratamiento antirretrovírico, las relaciones sexuales sin protección y numerosas parejas sexuales. Se deben emprender estudios similares en otros países de la Región, en particular en los lugares con mucha inmigración, para reducir tanto la posibilidad de que el virus varíe como el costo del tratamiento antirretrovírico.

High rate of mutation K103N causing resistance to nevirapine in Indian children with acquired immunodeficiency syndrome.

In north India the number of paediatric cases with acquired immunodeficiency syndrome (AIDS) is on the rise. Most drug combinations used for treatment of AIDS incorporate nevirapine, resistance to which develops very fast if given singly or because of unplanned interruptions. This paper investigates presence of mutations at codon 103 and codon 215 of the HIV pol gene causing resistance to nevirapine and zidovudine (AZT) respectively in 25 children with AIDS. Mutations T215Y and K103N were detected by a nested cum amplification refractory mutation system polymerase chain reaction (ARMS PCR) and the results were confirmed by direct sequencing in five randomly selected cases. Nineteen patients had received nevirapine containing regimen and six were drug naive. Mutation K103N was observed in 56% (14/25) of the children while mutation T215Y was found in none. Two of the six drug naïve children also showed K103N mutation. Thus, Indian children drug naïve or treated with nevirapine containing regimens show a high rate of mutation conferring resistance to nevirapine which calls for a judicious use of nevirapine both in antenatal and postnatal setting.

Caracterização molecular da região da integrase do gene pol de subtipos de HIV-1 prevalentes no Brasil: avaliação de marcadores de resistência e antigenicidade / Molecular characterization of the region of integrase of the gene pol of subtypes of HIV-1 in Brazil: evaluation of resistance markers and antigenicity

A diversidade genética do HIV-1 tem sido bem estudada tendo-se como alvo as proteínas estruturais. Porém, na região da integrase essa diversidade ainda não foi bem caracterizada. A integrase é uma enzima essencial para o ciclo de replicação do HIV-1 e é um alvo promissor para a terapia anti-retroviral. Atualmente, a terapia inclui inibidores de protease (PR), transcriptase reversa (TR) e de entrada viral. Entretanto, não está claro por quanto tempo os benefícios clínicos serão mantidos devido à emergência de variantes com resistência a múltiplas drogas. Neste contexto, o objetivo foi caracterizar a diversidade genética da integrase do HIV-1 em amostras dos subtipos B(B), C e F, obtidas de pacientes virgens de tratamento, e identificar a presença de mutações naturais relacionadas aos inibidores de integrase em amostras de indivíduos apresentando falha terapêutica, a fim de verificar se esta região ainda permaneceria como um alvo íntegro para o tratamento. O DNA proviral foi extraído de 111 amostras de sangue de indivíduos virgens de tratamento, infectados com os subtipos prevalentes no Brasil, previamente determinados com base na região C2-V3 do envelope. O RNA viral foi extraído de amostras de plasma de 30 indivíduos apresentando falha terapêutica às drogas correntes, infectados pelo subtipo B do HIV-1, previamente determinado com base no gene pol (PR/RT). As amostras foram amplificadas pela metodologia de nested PCR e seqüenciadas por sequenciamento automatizado. O pacote de programas DNASTAR, ClustalX e MEGA foram usados para edição, alinhamento, tradução, análise filogenética (neighbor-joining) e definição das seqüências consenso. Não verificamos a ocorrência de recombinação inter-gênica entre a região da integrase e os genes env e pr/rt, tipados previamente. Entretanto, identificamos genomas apresentando recombinação intra-gênica na região da integrase (3B/F, 3B/C) em amostras de indivíduos virgens de tratamento. Todos os recombinantes B/C apresentaram um...

Human immunodeficiency virus type 1 strains epidemic in Shenzhen / 中国医学科学院学报

<p><b>OBJECTIVE</b>To study the epidemic status of human immunodeficiency virus type 1 (HIV-1) subtypes in Shenzhen and to study their transmission source and routes.</p><p><b>METHODS</b>HIV-1 env and gag genes were amplified by nested PCR from uncultured peripheral blood mononuclear cells (PBMCs) obtained from 122 HIV-1 carriers confirmed in Shenzhen. The C2-V3 region (about 450 bp) of HIV-1 env and P17/ P24 region were sequenced.</p><p><b>RESULTS</b>Among 122 samples, 6 HIV-1 strains including 3 circulating recombinant forms (CRFs) of CRF01_AE, CRF08_BC, CRF07_BC and 3 subtypes of B', B, C were found in Shenzhen, and the percentages were 45.1% (55/122) for CRF01_AE, 31.1% (38/122) for CRF08_BC, 6.6% (8/122) for CRF07_BC, 14.8% (18/122) for B' subtype, 1.6% (2/122) for B subtype, and 0.8% (1/122) for C subtype. The intragroup genetic distances were (4.455 +/- 1.478)%, (2.997 +/- 1.345)%, (4.380 +/- 2.024)%, (5.186 +/- 2.487)%, and (4.869 +/- 2.638)%, respectively. In comparison with the sequence of respective international strains 01AE. TH. 90. CM240, 97CNGX-9F, CN. 97. C54A, B. US. 83. JRFL, and RLA2, the genetic distances were (5. 228 +/- 0.823)%, (3.634 +/- 1.073)%, (4.233 +/- 1.119)%, (4.950 +/- 2.564)%, and (5.795 +/- 2.198)%, respectively. The major subtypes found in injection drug users (IDUs) were CRF07_BC, CRF08_BC, and CRF01_AE strains. CRF01_AE and B' strains were epidemic mainly in sexual workers.</p><p><b>CONCLUSION</b>There are 3 HIV-1 subtypes (B', B, C) and 3 CRFs (CRF01_AE, CRF08_BC, CRF07_BC) epidemics in Shenzhen. The predominant subtypes varies among different transmission routes. While CRF01_AE is predominant among sexual workers, CRF08_BC and CRF01_AE are major subtypes among IDU population.</p>

Incidence of lamivudine resistance associated mutations in pol-gene of HIV-1 in patients from north India: a preliminary report.

Screening of drug-resistant variants is very important for the effective clinical management of HIV-infected patients and development of new strategies. The present study was aimed to detect codon-184 mutations in the pol-gene of HIV leading to resistance to lamivudine (3-TC) by nested cum ARMS-PCR approach in 10 treated and 9 treatment naive patients. For correlation the whole blood CD4/CD8 cell counts and the soluble TNFRII levels in plasma were also determined. Of the 19 patients tested, mutant variants were observed in 2 patients (Met Val in one and Met Val & lle in second) both being treated with 3-TC. No mutations were detected in the treatment-naive patients. The results confirmed that, drug resistant variants of codon-184 emerge rapidly in patients receiving 3-TC containing regimens including our population, which is mainly infected with subtypeC of the virus that could be detected along with wild viral population using sensitive approaches such as ARMS-PCR.

Genotypic antiretroviral resistance testing and phylogenetic analysis of protease and reverse transcriptase in antiretroviral drug-naïve AIDS patients in Henan province / 中华流行病学杂志

<p><b>OBJECTIVE</b>Frequency, type and clinical implications on protease and reverse transcriptase drug resistance mutations were investigated and phylogenetic analysis in antiretroviral drug-naïve AIDS patients was carried out in Henan province.</p><p><b>METHODS</b>45 plasma samples were separated from the anticoagulatory whole blood, from which reverse transcription-polymerase chain reaction technique was used to amplify the partial pol gene. The sequences were analysed for genotypic antiretroviral resistance and phylogenetic relation through landing the websites http://hivdb.stanford.edu and http://hiv-web.lanl.gov, under BioEdit and DNAClub software.</p><p><b>RESULTS</b>Partial pol sequences of 36 samples were successfully amplified. The major mutation rate of resistance to protease was 8.3% (3/36), including types D30A, V32A, G73C and V82A. Minor mutation rate of resistance was 100%, including types of L63PS (36/36), I93L (35/36), V77IL (34/36), A71IVT (10/36) and D60E (2/36). The mutation rate of resistance to reverse transcriptase was 38.9% (14/36). Mutation-scoring and clinical implication clewed drug resistance rates were 5.6% (2/36) and 22.2% (8/36) to protease inhibitors and reverse transcriptase inhibitors respectively, while 1 sample was potentially low-level resistant to all of the protease inhibitors and 3 samples to part of the reverse transcriptase inhibitors. Phylogenetic analysis revealed that the pol gene of 36 samples were highly homologous and having a near relative to B.US.83.RF ACC M17451. 36 samples seemed to have the same infection source while their resistance mutations were not due to drug-resistant virus infection but to the evolving of virus in vivo.</p><p><b>CONCLUSION</b>Most of the antiretroviral drug-naïve AIDS patients in Henan province were sensitive to the currently available antiviral medicine, but antiviral treatment must be in accordance with the strict procedure and to keep better adherence, to avoid the epidemics caused by drug-resistant virus.</p>

Construction and analysis of activity of an HIV-1/bovine immunodeficiency virus chimeric clone cDNA / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>Chimeric human/bovine immunodeficiency virus (HBIV) cDNA was constructed by replacing HIV tat and LTR with bovine immunodeficiency virus (BIV) tat and LTR to study the activity of BIV tat and LTR in the chimerae.</p><p><b>METHODS</b>The target fragments of BIV tat, LTR and HIV gag, pol, env were respectively amplified by using PCR and sequentially inserted into pBluescript SK(+) vector. The chimeric clone was transfected into human MT4 cells. The transcript and gene expression of the HBIV chimeric virus were detected by using RT-PCR and a reverse transcriptase assay, respectively.</p><p><b>RESULTS</b>BIV tat mRNA and HIV gag mRNA were detected. The reverse transcriptase activity of the chimeric virus was analyzed in the fluctuation curve.</p><p><b>CONCLUSIONS</b>In chimeric HBIV cDNA transfected MT?4 cells, BIV tat and HIV gag were transcripted. The reverse transcriptase of the chimeric virus had biological activity. These data suggest that in MT4 cells, BIV LTR had promoter activity and BIV tat had the function of transactivation in the chimeric virus. The study of the chimeric virus with infectivity is in progress.</p>

Prevalence of HIV-1 drug resistance in antiretroviral-naive pregnant Thai women.

HIV-1 drug resistance may limit the use of antiretrovirals when attempting to reduce the vertical transmission rate. Establishing the prevalence of the HIV-1 mutations associated with antiretroviral resistance in pregnant women will enable clinicians to maximize the chances of preventing vertical transmission. In order to determine the prevalence of HIV-1 resistant strains among antiretroviral-naive pregnant Thai women, the nucleotide sequences of the HIV-1 polymerase (pol) gene were evaluated. The plasma samples were collected from the women during the 34th week of pregnancy: numerous secondary mutations could be found in the reverse transcriptase (RT) and protease gene, while no primary mutations in the pol gene were found. The result also showed that by detecting the delta32bp deletion within the CCR 5 locus, it was evident that none of HIV-1 infected individuals had homozygous or heterozygous delta32bp deletions of the CCR5 gene; moreover, no CCR5 gene mutations were found in any individual.

Indentification of pol Gene Mutation among BLV Proviruses Found in the Southern Provinve of Korea

No Abstract Available.