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Confronting the Ethical Conduct of Resuscitation Research: a consensus opinion.

An objective of the 2005 Academic Emergency Medicine Consensus Conference, "Ethical Conduct of Resuscitation Research," was to identify if consensus exists regarding application of the Food and Drug Administration (FDA) Final Rule allowing an exception from informed consent in resuscitation research. At the start of the consensus conference, 49 attendees participated in a survey containing three sections: 1) demographic questions characterizing respondents, 2) questions regarding application of the FDA Final Rule, and 3) complexities associated with seeking informed consent in an emergency setting. Consensus analysis was used to determine if a formal consensus was reached, relying on a Bayesian posterior probability of 0.99 to consider survey responses a "consensus." Respondents demonstrated consensus regarding the need to further refine and standardize application of the FDA Final Rule in resuscitation research. However, participants agreed that current regulations provide adequate and appropriate protection to safeguard patients. Complexities associated with seeking informed consent in emergency departments were prevalent among most institutions represented at the conference. There was general agreement that current efforts to safeguard human subjects are effective, but participants agreed that refinements to and standardization of the FDA Final Rule would facilitate resuscitation research and enhance patient safety.

Consensus Statements as Topic↗

Interactions of estrogen- and thyroid hormone receptors on a progesterone receptor estrogen response element (ERE) sequence: a comparison with the vitellogenin A2 consensus ERE.

The identification of hormone response elements in the promoter regions of hormonally regulated genes has revealed a striking similarity between the half-site of the estrogen-response element (ERE) and a consensus sequence constituting the thyroid hormone-response element. Because of the potential for thyroid hormone (T3) to affect estrogen (E)- and progesterone-dependent female reproductive behavior via EREs, we have begun to investigate the activity of an ERE identified in the progesterone receptor (PR) proximal promoter and its interactions with the estrogen receptor (ER) and thyroid hormone receptors (TR). In addition, we have compared ER and TR interactions on the PR ERE construct with that of the vitellogenin A2 (vit A2) consensus ERE. Electrophoretic mobility shift assays demonstrated that TR binds to the PR ERE as well as to the consensus ERE sequence in vitro. Further, these two EREs were differentially regulated by T3 in the presence of TR. T3 in the presence of TR alpha increased transcription from a PR ERE construct approximately 5-fold and had no inhibitory effect on E induction. Similarly, T3 also activated a beta-galactosidase reporter construct containing PR promoter sequences spanning -1400 to +700. In addition, the TR isoforms beta1 and beta2 also stimulated transcription from the PR ERE construct by 5- to 6-fold. A TR alpha mutant lacking the ability to bind AGGTCA sequences in vitro failed to activate transcription from the PR ERE construct, demonstrating dependence on DNA binding. In contrast to its actions on the PR ERE construct, TR alpha did not activate transcription from the vit A2 consensus ERE but rather attenuated E-mediated transcriptional activation. Attenuation from the vit A2 consensus ERE is not necessarily dependent on DNA binding as the TR alpha DNA binding mutant was still able to inhibit E-dependent transactivation. In contrast to TR alpha, the isoforms TRbeta1 and TRbeta2 failed to inhibit E-induced activation from the vit A2 consensus ERE. These results demonstrate that the PR ERE construct differs from the vit A2 consensus ERE in its ability to respond to TRs and that divergent pathways exist for activation and inhibition by TR. Since ERs, PRs, and TRs are all present in hypothalamic neurons, these findings may be significant for endocrine integration, which is important for reproductive behavior.

Animals↗

A collaborative platform for consensus sessions in pathology over Internet.

The design of valid databases in pathology faces the problem of diagnostic disagreement between pathologists. Organizing consensus sessions between experts to reduce the variability is a difficult task. The TRIDEM platform addresses the issue to organize consensus sessions in pathology over the Internet. In this paper, we present the basis to achieve such collaborative platform. On the one hand, the platform integrates the functionalities of the IDEM consensus module that alleviates the consensus task by presenting to pathologists preliminary computed consensus through ergonomic interfaces (automatic step). On the other hand, a set of lightweight interaction tools such as vocal annotations are implemented to ease the communication between experts as they discuss a case (interactive step). The architecture of the TRIDEM platform is based on a Java-Server-Page web server that communicate with the ObjectStore PSE/PRO database used for the object storage. The HTML pages generated by the web server run Java applets to perform the different steps (automatic and interactive) of the consensus. The current limitations of the platform is to only handle a synchronous process. Moreover, improvements like re-writing the consensus workflow with a protocol such as BPML are already forecast.

Computer Systems↗

Consensus in interpersonal perception: acquaintance and the big five.

Consensus refers to the extent to which judges agree in their ratings of a common target. Consensus has been an important area of research in social and personality psychology. In this article, generalizability theory is used to develop a percentage of total variance measure of consensus. This measure is used to review the level of consensus across 32 studies by considering the role of acquaintance level and trait dimension. The review indicates that consensus correlations ranged from zero to about .3, with higher levels of consensus for ratings of Extraversion. The studies do not provide evidence that consensus increases with increasing acquaintance, a counterintuitive result that can be accounted for by a theoretical model (D.A. Kenny, 1991, in press). Problems in the interpretation of longitudinal research are reviewed.

Female↗

Definition of a consensus DNA-binding site for PecS, a global regulator of virulence gene expression in Erwinia chrysanthemi and identification of new members of the PecS regulon.

In Erwinia chrysanthemi, production of pectic enzymes is modulated by a complex network involving several regulators. One of them, PecS, which belongs to the MarR family, also controls the synthesis of various other virulence factors, such as cellulases and indigoidine. Here, the PecS consensus-binding site is defined by combining a systematic evolution of ligands by an exponential enrichment approach and mutational analyses. The consensus consists of a 23-base pair palindromic-like sequence (C(-11)G(-10)A(-9)N(-8)W(-7)T(-6)C(-5)G(-4)T(-3)A(-2))T(-1)A(0)T(1)(T(2)A(3)C(4)G(5)A(6)N(7)N(8)N(9)C(10)G(11)). Mutational experiments revealed that (i) the palindromic organization is required for the binding of PecS, (ii) the very conserved part of the consensus (-6 to 6) allows for a specific interaction with PecS, but the presence of the relatively degenerated bases located apart significantly increases PecS affinity, (iii) the four bases G, A, T, and C are required for efficient binding of PecS, and (iv) the presence of several binding sites on the same promoter increases the affinity of PecS. This consensus is detected in the regions involved in PecS binding on the previously characterized target genes. This variable consensus is in agreement with the observation that the members of the MarR family are able to bind various DNA targets as dimers by means of a winged helix DNA-binding motif. Binding of PecS on a promoter region containing the defined consensus results in a repression of gene transcription in vitro. Preliminary scanning of the E. chrysanthemi genome sequence with the consensus revealed the presence of strong PecS-binding sites in the intergenic region between fliE and fliFGHIJKLMNOPQR which encode proteins involved in the biogenesis of flagellum. Accordingly, PecS directly represses fliE expression. Thus, PecS seems to control the synthesis of virulence factors required for the key steps of plant infection.

Amino Acid Motifs↗

A new method for finding long consensus patterns in nucleic acid sequences.

We describe a fast computer algorithm for identifying consensus patterns in DNA sequences. The method requires no prior assumptions about the consensus pattern other than its length. In particular no previous knowledge of the frequency or spacing of consensus patterns is required. However, a priori information about the shape of the consensus pattern, or invariability of individual positions, or the overall conservation level, can be utilized to enhance the selectivity and sensitivity of search. As the number of all possible consensus words increases very rapidly with length, comprehensive searches have usually been restricted to a maximum of 10-12 nucleotides, even when large mainframes are used. Our algorithm enables searching for consensus patterns of this order on current mid-range and powerful microcomputers. Searches may be conducted on single, long sequences or a set of possibly aligned shorter sequences. We give examples of identified consensus patterns in both prokaryotic and eukaryotic DNA sequences, along with some typical program timings.

Base Sequence↗

Source consistency, distinctiveness, and consensus: the three dimensions of the Kelley ANOVA model in persuasion.

Based on a conceptual analysis and existing research, the authors propose that the three source dimensions specified in the ANOVA model play similar roles in persuasion as other source characteristics (e.g., expertise). Two studies test assumptions derived from this approach regarding the effects of different combinations of consistency and consensus (Study 1) and distinctiveness and consensus (Study 2). Combinations resulting in contradictory (vs. similar) inferences regarding message validity should affect judgmental confidence and, consequently, affect message scrutiny. Study 1 shows that, as predicted, high consistency/low consensus and low consistency/high consensus (incongruent combinations) lead to higher desired confidence and more extensive message elaboration than high consistency/high consensus and low consistency/low consensus (congruent combinations). Similarly, Study 2 reveals heightened message scrutiny given incongruent (vs. congruent) combinations of distinctiveness and consensus. Results are discussed with respect to majority/minority influence processes and multiple source characteristics.

Adult↗

[Establishment of consensus sequence of PreS/S of hepatitis B virus with genotype B/serotype adw2 or genotype C/serotype adrq+ prevailing in Chongqing of China].

OBJECTIVE: To develop consensus sequence of HBV PreS/S with different subtype in Chongqing of China. METHODS: The gene of PreS/S of HBV in 18 AsC was sequenced. The genotype and serotype of HBV were determined. The main HBV strain prevailing in Chongqing was identified to establish its consensus sequence. RESULTS: It was found that 9 strains were genotype B/serotype adw2, 6 were genotype C/serotype adrq+ and 3 were genotype B/serotype ayw1. The consensus sequence of PreS/S of HBV with genotype B/serotype adw2 and genotype C/serotype adrq+ were established. There were 6 nucleotide variants which causing 4 amino acids change between consensus sequence of PreS/S with genotype B/serotype adw2 in Chongqing and in Southeast of China (homology showed 99.5% and 99.0% respectively). There were 13 different sites that caused 4 amino acids change between consensus sequence of PreS/S with genotype C/serotype adrq+ in Chongqing and in Northeast and South of China (homology showed 98.9% and 99.0% respectively). Comparing the two consensus sequence of PreS/S gene of different subtype HBV in Chongqing, there was 95 variants which caused 40 amino acids variants (the homology was 92.1% and 90.0% respectively). CONCLUSION: The consensus sequence of PreS/S of hepatitis B virus with genotype B/serotype adw2 and genotype C/serotype adrq+ prevailing in Chongqing was established.

Adolescent↗

Infectious disease testing for blood transfusions. NIH Consensus Development Panel on Infectious Disease Testing for Blood Transfusions.

OBJECTIVE: To provide physicians and other transfusion medicine professionals with a current consensus on infectious disease testing for blood transfusions. PARTICIPANTS: A nonfederal, nonadvocate, 12-member consensus panel representing the fields of hematology, infectious disease, transfusion medicine, epidemiology, and biostatistics and a public representative. In addition, 23 experts in hematology, cardiology, transfusion medicine, infectious disease, and epidemiology presented data to the consensus panel and a conference audience of 450. EVIDENCE: The literature was searched through MEDLINE and an extensive bibliography of references was provided to the panel and the conference audience. Experts prepared abstracts with relevant citations from the literature. Scientific evidence was given precedence over clinical anecdotal experience. CONSENSUS: The panel, answering predefined consensus questions, developed their conclusions based on the scientific evidence presented in open forum and the scientific literature. CONSENSUS STATEMENT: The panel composed a draft statement that was read in its entirety and circulated to the experts and the audience for comment. Thereafter, the panel resolved conflicting recommendations and released a revised statement at the end of the conference. The panel finalized the revisions within a few weeks after the conference. CONCLUSIONS: The serum alanine aminotransferase test should be discontinued as a surrogate marker for blood donors likely to transmit posttransfusion non-A, non-B hepatitis infection since specific hepatitis C antibody testing has eliminated more than 85% of these cases. Antibody to hepatitis B core antigen testing should continue as it may prevent some cases of posttransfusion hepatitis B; it may also act as a surrogate marker for human immunodeficiency virus (HIV) infection in donors and may prevent a small number of cases of transfusion-transmitted HIV infection. Syphilis testing should continue until adequate data can determine its effect on the rarity of transfusion-transmitted syphilis. Vigilant public health surveillance is critical in responding to emerging infectious disease threats to the blood supply.

Alanine Transaminase↗

Latin American consensus on the medical oncologic management of early-stage HR+/HER2- breast cancer: Addressing regional disparities in Spanish-speaking countries.

PURPOSE: Substantial disparities persist in managing early-stage hormone receptor-positive, HER2-negative (HR+/HER2-) breast cancer across Spanish-speaking Latin America, including limited access to genomic testing, systemic therapies, and fertility preservation. The Latin American Breast Cancer Association (LABCA) convened an expert panel to produce the first consensus tailored to Spanish-speaking countries. METHODS: A literature review (Embase, PubMed, Scopus, ClinicalKey, LILACS; 2014-2025), informed by ESMO/ASCO/NCCN/SEOM guidelines and registered in PROSPERO (CRD42024565706), supported statement development. A steering committee of three experts of Spanish nationality supervised the process. Twenty-one specialists from 11 countries participated in a modified Delphi process; 31 items were voted in Round 1 and 25 statements were retained within scope. Consensus was pre-defined as ≥80% agreement (or median 7-9), with a mean/outlier rule reported alongside. RESULTS: Applying the ≥80% rule, 22 of 25 statements (88%) reached full consensus; three (1.3, 2.4, 3.3; 75-76%) were near-consensus and retained with caveats. Recommendations integrated clinicopathologic and molecular factors to guide risk stratification; genomic assays were reserved for selected scenarios and discouraged in very low-risk tumors or ≥4 positive lymph nodes. Consensus also covered ovarian suppression plus endocrine therapy, fertility preservation, sexual-health and genetic evaluation, and adjuvant CDK4/6 and PARP inhibitors when accessible. Marked heterogeneity in access was documented by country and sector. CONCLUSION: This consensus provides the first region-specific, evidence-based, resource-adapted recommendations for early-stage HR+/HER2- breast cancer in Spanish-speaking Latin America, aiming to reduce disparities and strengthen equitable oncology care.

Humans↗

The Montreal definition and classification of gastroesophageal reflux disease: a global evidence-based consensus.

OBJECTIVES: A globally acceptable definition and classification of gastroesophageal reflux disease (GERD) is desirable for research and clinical practice. The aim of this initiative was to develop a consensus definition and classification that would be useful for patients, physicians, and regulatory agencies. METHODS: A modified Delphi process was employed to reach consensus using repeated iterative voting. A series of statements was developed by a working group of five experts after a systematic review of the literature in three databases (Embase, Cochrane trials register, Medline). Over a period of 2 yr, the statements were developed, modified, and approved through four rounds of voting. The voting group consisted of 44 experts from 18 countries. The final vote was conducted on a 6-point scale and consensus was defined a priori as agreement by two-thirds of the participants. RESULTS: The level of agreement strengthened throughout the process with two-thirds of the participants agreeing with 86%, 88%, 94%, and 100% of statements at each vote, respectively. At the final vote, 94% of the final 51 statements were approved by 90% of the Consensus Group, and 90% of statements were accepted with strong agreement or minor reservation. GERD was defined as a condition that develops when the reflux of stomach contents causes troublesome symptoms and/or complications. The disease was subclassified into esophageal and extraesophageal syndromes. Novel aspects of the new definition include a patient-centered approach that is independent of endoscopic findings, subclassification of the disease into discrete syndromes, and the recognition of laryngitis, cough, asthma, and dental erosions as possible GERD syndromes. It also proposes a new definition for suspected and proven Barrett's esophagus. CONCLUSIONS: Evidence-based global consensus definitions are possible despite differences in terminology and language, prevalence, and manifestations of the disease in different countries. A global consensus definition for GERD may simplify disease management, allow collaborative research, and make studies more generalizable, assisting patients, physicians, and regulatory agencies.

Delphi Technique↗

NIH consensus conference. Cochlear implants in adults and children.

OBJECTIVE: To provide clinicians and other health care providers with a current consensus on the benefits, limitations, and technical and safety issues that need to be considered in the use of cochlear implants. PARTICIPANTS: A nonfederal, nonadvocate, 14-member consensus panel representing the fields of otolaryngology, audiology, speech-language pathology, pediatrics, psychology, and education, and including a public representative. In addition, 24 experts in auditory anatomy and physiology, otolaryngology, audiology, aural rehabilitation, education, speech-language pathology, and bioengineering presented data to the consensus panel and a conference audience of 650. EVIDENCE: The literature was searched through MEDLINE and an extensive bibliography of references was provided to the panel and the conference audience. Experts prepared abstracts with relevant citations from the literature. Scientific evidence was given precedence over clinical anecdotal experience. CONSENSUS: The panel, answering predefined consensus questions, developed its conclusions based on the scientific evidence presented in open forum and the scientific literature. CONSENSUS STATEMENT: The panel composed a draft statement that was read in its entirety and circulated to the experts and the audience for comment. Thereafter, the panel resolved conflicting recommendations and released a revised statement at the end of the conference. The panel finalized the revisions within a few weeks after the conference. CONCLUSIONS: Cochlear implantation improves communication ability in most adults with severe-to-profound deafness and frequently leads to positive psychological and social benefits as well. Currently, children at least 2 years old and adults with profound deafness are candidates for implantation. Cochlear implant candidacy should be extended to adults with severe hearing impairment and open-set sentence discrimination that is less than or equal to 30% in the best-aided condition. Access to optimal education and (re)habilitation services is important for adults and is critical for children to maximize the benefits available from cochlear implantation.

Adult↗

Diagnosis and treatment of depression in late life. Consensus statement update.

OBJECTIVE: To reexamine the conclusions of the 1991 National Institutes of Health Consensus Panel on Diagnosis and Treatment of Depression in Late Life in light of current scientific evidence. PARTICIPANTS: Participants included National Institutes of Health staff and experts drawn from the Planning Committee and presenters of the 1991 Consensus Development Conference. EVIDENCE: Participants summarized relevant data from the world scientific literature on the original questions posed for the conference. PROCESS: Participants reviewed the original consensus statement and identified areas for update. The list of issues was circulated to all participants and amended to reflect group agreement. Selected participants prepared first drafts of the consensus update for each issue. All drafts were read by all participants and were amended and edited to reflect group consensus. CONCLUSIONS: The review concluded that, although the initial consensus statement still holds, there is important new information in a number of areas. These areas include the onset and course of late-life depression; comorbidity and disability; sex and hormonal issues; newer medications, psychotherapies, and approaches to long-term treatment; impact of depression on health services and health care resource use; late-life depression as a risk factor for suicide; and the importance of the heterogeneous forms of depression. Depression in older people remains a significant public health problem. The burden of unrecognized or inadequately treated depression is substantial. Efficacious treatments are available. Aggressive approaches to recognition, diagnosis, and treatment are warranted to minimize suffering, improve overall functioning and quality of life, and limit inappropriate use of health care resources.

Age Factors↗

Expert consensus for training in perioperative echocardiography in the province of Quebec.

PURPOSE: Establish an expert consensus for training in perioperative echocardiography in the province of Quebec. METHODS: Cardiac anesthesiologists practicing in the province of Quebec with expertise in echocardiography were involved in the development of a multicentre expert consensus on training in perioperative echocardiography. Guidelines for training in adult echocardiography, transesophageal echocardiography and perioperative echocardiography by the American Society of Echocardiography (ASE), the American College of Cardiology (ACC) and/or the Society of Cardiovascular Anesthesiologists (SCA) were reviewed. RESULTS: A basic, advanced and director level of expertise were identified for training in perioperative echocardiography. The total number of echocardiographic examinations to achieve each of these levels of expertise remains unchanged from the 2002 ASE-SCA guidelines. However, the recommended proportion of examinations performed personally is increased in the Quebec expert consensus for both the basic and the advanced level of training to ensure proficiency in echocardiography while providing anesthesia care to the patient. A level of autonomy in perioperative echocardiography is also identified in the basic level of training as defined in the Quebec expert consensus. Maintenance of competence, certification in the perioperative transesophageal echocardiography (PTE) examination and duration of training are outlined for each of the three levels of training in the Quebec expert consensus but are not part of the recent 2002 ASE-SCA guidelines. CONCLUSION: Adequate perioperative echocardiographic training is an important aspect of cardiovascular anesthesia. The ACC, ASE and SCA guidelines for training in echocardiography were modified to reflect the expert consensus of anesthesiologists in the province of Quebec.

Anesthesiology↗

Consensus conferences must include a systematic search and categorization of the evidence.

BACKGROUND: Ideally, a consensus panel combines expert knowledge with external evidence derived from the literature. To date, many consensus conferences do not use a structured approach to search the literature, but simply compile an add-on reference list from all papers cited by the panelists. This study examined how well such panelists retrieved the relevant literature. METHODS: We used the reference lists of nine surgeons who took part in a consensus conference on common bile duct stones. We included all papers that were referred to as randomized controlled trials (RCTs). We then compared this list with a database search in order to calculate sensitivity and specificity. RESULTS: The nine experts cited between 35 and 518 papers, but only eight papers on average were RCTs. Of the 49 papers that the experts believed to be RCTs, only 23 actually were RCTs. The sensitivity resp. specificity for correctly identifying an RCT was 0.21 (95% Cl, 0.11-0.30) resp. 0.80 (95% Cl; 0.64-0.95). RCTs that included the word "randomized" in their title were significantly more likely to be identified (relative risk, 1.31; 95% Cl, 1.18-1.45). CONCLUSION: Our data indicate that consensus panelists usually do not perform systematic literature searches, but simply use their favorite papers to back up their arguments. Because this may lead to a biased selection of the evidence base on which the consensus statements are founded, a systematic search of all relevant articles should become a mandatory task in any consensus or guideline process.

Consensus Statements as Topic↗

The twin arginine consensus motif of Tat signal peptides is involved in Sec-independent protein targeting in Escherichia coli.

In Escherichia coli a subset of periplasmic proteins is exported through the Tat pathway to which substrates are directed by an NH(2)-terminal signal peptide containing a consensus SRRXFLK "twin arginine" motif. The importance of the individual amino acids of the consensus motif for in vivo Tat transport has been assessed by site-directed mutagenesis of the signal peptide of the Tat substrate pre-SufI. Although the invariant arginine residues are crucial for efficient export, we find that slow transport of SufI is still possible if a single arginine is conservatively substituted by a lysine residue. Thus, in at least one signal peptide context there is no absolute dependence of Tat transport on the arginine pair. The consensus phenylalanine residue was found to be a critical determinant for efficient export but could be functionally substituted by leucine, another amino acid with a highly hydrophobic side chain. Unexpectedly, the consensus lysine residue was found to retard Tat transport. These observations and others suggest that the sequence conservation of the Tat consensus motif is a reflection of the functional importance of the consensus residues. Tat signal peptides characteristically have positively charged carboxyl-terminal regions. However, changing the sign of this charge does not affect export of SufI.

Amino Acid Substitution↗

Human GC-AG alternative intron isoforms with weak donor sites show enhanced consensus at acceptor exon positions.

It has been previously observed that the intrinsically weak variant GC donor sites, in order to be recognized by the U2-type spliceosome, possess strong consensus sequences maximized for base pair formation with U1 and U5/U6 snRNAs. However, variability in signal strength is a fundamental mechanism for splice site selection in alternative splicing. Here we report human alternative GC-AG introns (for the first time from any species), and show that while constitutive GC-AG introns do possess strong signals at their donor sites, a large subset of alternative GC-AG introns possess weak consensus sequences at their donor sites. Surprisingly, this subset of alternative isoforms shows strong consensus at acceptor exon positions 1 and 2. The improved consensus at the acceptor exon can facilitate a strong interaction with U5 snRNA, which tethers the two exons for ligation during the second step of splicing. Further, these isoforms nearly always possess alternative acceptor sites and exhibit particularly weak polypyrimidine tracts characteristic of AG-dependent introns. The acceptor exon nucleotides are part of the consensus required for the U2AF(35)-mediated recognition of AG in such introns. Such improved consensus at acceptor exons is not found in either normal or alternative GT-AG introns having weak donor sites or weak polypyrimidine tracts. The changes probably reflect mechanisms that allow GC-AG alternative intron isoforms to cope with two conflicting requirements, namely an apparent need for differential splice strength to direct the choice of alternative sites and a need for improved donor signals to compensate for the central mismatch base pair (C-A) in the RNA duplex of U1 snRNA and the pre-mRNA. The other important findings include (i) one in every twenty alternative introns is a GC-AG intron, and (ii) three of every five observed GC-AG introns are alternative isoforms.

Alternative Splicing↗

HIV-1 MN Env 15-mer peptides better detect HIV-1 specific CD8 T cell responses compared with consensus subtypes B and M group 15-mer peptides.

OBJECTIVE: To compare the ability of three Env (15-mer) peptide sets derived from the HIV-1 MN, the subtype B consensus, and the group M consensus to detect HIV-1 specific interferon (IFN)-gamma responses in HIV-1 subtype B infected subjects. METHODS: Peripheral blood mononuclear cells were obtained from 17 HIV-1 subtype B seropositive and 5 HIV-1 seronegative subjects. Peptide matrices comprising each peptide set were used in IFN-gamma Elispot assays to screen for T cell epitopes. Following matrix deconvolution, individual peptides were analyzed by IFN-gamma intracellular cytokine-staining to confirm and characterize the responding cells. RESULTS: HIV specific IFN-gamma responses were detected in 17 of 17 HIV-1 seropositive and none of 5 HIV-1 seronegative subjects by Elispot. Within the 17 HIV-1 seropositives, 16, 14, and 11 subjects responded to MN, B consensus, and group M env peptides, respectively. Responses were confirmed by intracellular cytokine analysis in 14 subjects and were in the CD3CD8 compartment. Cross-recognition of 'equivalent' peptides (i.e., peptides mapping to the same sequence region from the three peptide sets) was observed in 9 of 17 subjects. Peptide set specific responses to individual peptides were also observed; 11, 1, and 1 subjects demonstrated peptide set specific responses to MN, B consensus, and consensus group M, respectively. CONCLUSION: MN derived Env peptides were better able to detect HIV-1 specific CD8 T cell responses, many of which were not detectable by the equivalent clade or group consensus peptides. No single peptide set detected all the IFN-gamma responses within an individual. These results demonstrate the importance of reagent selection for monitoring of HIV responses in HIV-1 infected individuals and subsequently vaccine recipients.

Adult↗