Clustal W and Clustal X version 2.0

SUMMARY

The Clustal W and Clustal X multiple sequence alignment programs have been completely rewritten in C++. This will facilitate the further development of the alignment algorithms in the future and has allowed proper porting of the programs to the latest versions of Linux, Macintosh and Windows operating systems.

AVAILABILITY

The programs can be run on-line from the EBI web server: http://www.ebi.ac.uk/tools/clustalw2. The source code and executables for Windows, Linux and Macintosh computers are available from the EBI ftp site ftp://ftp.ebi.ac.uk/pub/software/clustalw2/

Cognitive reappraisal of emotion: a meta-analysis of human neuroimaging studies

In recent years, an explosion of neuroimaging studies has examined cognitive reappraisal, an emotion regulation strategy that involves changing the way one thinks about a stimulus in order to change its affective impact. Existing models broadly agree that reappraisal recruits frontal and parietal control regions to modulate emotional responding in the amygdala, but they offer competing visions of how this is accomplished. One view holds that control regions engage ventromedial prefrontal cortex (vmPFC), an area associated with fear extinction, that in turn modulates amygdala responses. An alternative view is that control regions modulate semantic representations in lateral temporal cortex that indirectly influence emotion-related responses in the amygdala. Furthermore, while previous work has emphasized the amygdala, whether reappraisal influences other regions implicated in emotional responding remains unknown. To resolve these questions, we performed a meta-analysis of 48 neuroimaging studies of reappraisal, most involving downregulation of negative affect. Reappraisal consistently 1) activated cognitive control regions and lateral temporal cortex, but not vmPFC, and 2) modulated the bilateral amygdala, but no other brain regions. This suggests that reappraisal involves the use of cognitive control to modulate semantic representations of an emotional stimulus, and these altered representations in turn attenuate activity in the amygdala.

The InterPro database, an integrated documentation resource for protein families, domains and functional sites

Signature databases are vital tools for identifying distant relationships in novel sequences and hence for inferring protein function. InterPro is an integrated documentation resource for protein families, domains and functional sites, which amalgamates the efforts of the PROSITE, PRINTS, Pfam and ProDom database projects. Each InterPro entry includes a functional description, annotation, literature references and links back to the relevant member database(s). Release 2.0 of InterPro (October 2000) contains over 3000 entries, representing families, domains, repeats and sites of post-translational modification encoded by a total of 6804 different regular expressions, profiles, fingerprints and Hidden Markov Models. Each InterPro entry lists all the matches against SWISS-PROT and TrEMBL (more than 1,000,000 hits from 462,500 proteins in SWISS-PROT and TrEMBL). The database is accessible for text- and sequence-based searches at http://www.ebi.ac.uk/interpro/. Questions can be emailed to interhelp@ebi.ac.uk.

CpG islands as gene markers in the human genome

CpG islands are short, dispersed regions of unmethylated DNA with a high frequency of CpG dinucleotides relative to the bulk genome. We have analyzed 375 genes and 58 pseudogenes from the human entries in the EMBL Database for the presence of CpG islands. All 240 islands identified are associated with genes, and almost all cover at least a part of one exon; i.e., they are useful landmarks in the genome for identifying genes. More than half of the genes analyzed were associated with islands. All housekeeping and widely expressed genes have a CpG island covering the transcription start, whereas 40% of the genes with a tissue-specific or limited expression are associated with islands. In this latter group of genes, the position of the islands was not biased toward the 5' end of the transcription unit.

Effect of anthelmintic treatment on the allergic reactivity of children in a tropical slum

It is well known that helminthic infection can cause a polyclonal stimulation of the synthesis of IgE, which is dependent on interleukin-4 (IL-4) production, and it has been suggested that this can modulate the expression of allergic reactivity in tropical populations. We evaluated the effect of regular anthelmintic treatment, for a period of 22 months, on certain aspects of the allergic reactivity of children in a slum area of Caracas, Venezuela, where helminths are endemic. The treatment (Oxantel-Pyrantel; Quantrel) effectively eliminated intestinal helminthic infection and resulted in a significant decrease in the initially elevated total serum IgE levels. IL-4 was detectable in the serum, and a significant reduction in IL-4 was also observed after treatment. In contrast, both the immediate-hypersensitivity skin-test reactivity and serum levels of specific IgE antibody against environmental allergens were markedly increased in the treated children. In a group of children who were also evaluated in the same slum, but who declined treatment, a substantial increase in helminthic infection occurred, which was related to an acute deterioration of the socioeconomic conditions of Venezuela over the course of our study period. This was paralleled by a considerable increase in total IgE levels in these children and a decrease in the skin-test reactivities and specific IgE levels. The application of Prausnitz-Küstner passive transfer tests and analysis of specific IgE antibody levels indicated that the polyclonal stimulation of IgE synthesis by helminthic parasites results in mast cell Fc epsilon receptor saturation and suppression of specific IgE antibody synthesis. This inhibition of allergic reactivity is reversible by anthelmintic treatment.

InterPro--an integrated documentation resource for protein families, domains and functional sites

MOTIVATION

InterPro is a new integrated documentation resource for protein families, domains and functional sites, developed initially as a means of rationalising the complementary efforts of the PROSITE, PRINTS, Pfam and ProDom database projects.

RESULTS

Merged annotations from PRINTS, PROSITE and Pfam form the InterPro core. Each combined InterPro entry includes functional descriptions and literature references, and links are made back to the relevant parent database(s), allowing users to see at a glance whether a particular family or domain has associated patterns, profiles, fingerprints, etc. Merged and individual entries (i.e. those that have no counterpart in the companion resources) are assigned unique accession numbers. Release 1.2 of InterPro (June 2000) contains over 3000 entries, representing families, domains, repeats and sites of post-translational modification (PTMs) encoded by 6581 different regular expressions, profiles, fingerprints and Hidden Markov Models (HMMs). Each InterPro entry lists all the matches against SWISS-PROT and TrEMBL (more than 1000000 hits from 264333 different proteins out of 384572 in SWISS-PROT and TrEMBL).

Retinoschisis associated with optic nerve pits

Stereoscopic transparencies studied with magnification and projection suggest that the retinal elevation that communicates with optic pits is frequently a schisislike separation of the internal layers of retina. Thirteen of 15 eyes with optic pits and maculopathy fit the schisis pattern. Separation of the outer layers of the retina is a secondary phenomenon that starts in the macula.

A screen for new trithorax group genes identified little imaginal discs, the Drosophila melanogaster homologue of human retinoblastoma binding protein 2

The proteins encoded by two groups of conserved genes, the Polycomb and trithorax groups, have been proposed to maintain, at the level of chromatin structure, the expression pattern of homeotic genes during Drosophila development. To identify new members of the trithorax group, we screened a collection of deficiencies for intergenic noncomplementation with a mutation in ash1, a trithorax group gene. Five of the noncomplementing deletions uncover genes previously classified as members of the Polycomb group. This evidence suggests that there are actually three groups of genes that maintain the expression pattern of homeotic genes during Drosophila development. The products of the third group appear to be required to maintain chromatin in both transcriptionally inactive and active states. Six of the noncomplementing deficiencies uncover previously unidentified trithorax group genes. One of these deficiencies removes 25D2-3 to 26B2-5. Within this region, there are two, allelic, lethal P-insertion mutations that identify one of these new trithorax group genes. The gene has been called little imaginal discs based on the phenotype of mutant larvae. The protein encoded by the little imaginal discs gene is the Drosophila homologue of human retinoblastoma binding protein 2.

Searching for autolysin functions. Characterization of a pneumococcal mutant deleted in the lytA gene

The first mutant of Streptococcus pneumoniae showing a complete deletion in the lytA gene coding for the N-acetylmuramyl-L-alanine amidase has been isolated and characterized. This amidase was previously the only autolysin detected in this species. This mutant shows a normal growth rate and can be transformed using either chromosomal or plasmid DNA. The most remarkable biological consequences of the absence of the amidase are the formation of small chains (six to eight cells) and the absence of lysis in the stationary phase of growth. In addition, this mutant exhibits a tolerant response against the beta-lactam antibiotics.

Liver preservation with machine perfusion and a newly developed cell-free oxygen carrier solution under subnormothermic conditions

We describe a new preservation modality combining machine perfusion (MP) at subnormothermic conditions(21 °C) with a new hemoglobin-based oxygen carrier (HBOC) solution. MP (n=6) was compared to cold static preservation (CSP; n=6) in porcine orthotopic liver transplants after 9 h of cold ischemia and 5-day follow-up. Recipients' peripheral blood, serial liver biopsies, preservation solutions and bile specimens were collected before, during and after liver preservation. Clinical laboratorial and histological analyses were performed in addition to mitochondrial functional assays, transcriptomic, metabolomic and inflammatory inflammatory mediator analyses. Compared with CSP, MP animals had: (1) significantly higher survival (100%vs. 33%; p<0.05); (2) superior graft function (p<0.05);(3) eight times higher hepatic O2 delivery than O2 consumption (0.78 mL O2/g/h vs. 0.096 mL O2/g/h) during MP; and (4) significantly greater bile production (MP=378.5 ± 179.7; CS=151.6 ± 116.85). MP downregulated interferon (IFN)-α and IFN-γ in liver tissue. MP allografts cleared lactate, produced urea, sustained gluconeogenesis and produced hydrophilic bile after reperfusion. Enhanced oxygenation under subnormothermic conditions triggers regenerative and cell protective responses resulting in improved allograft function. MP at 21 °C with the HBOC solution significantly improves liver preservation compared to CSP.

Alcohol and cigarette consumption predict mortality in patients with head and neck cancer: a pooled analysis within the International Head and Neck Cancer Epidemiology (INHANCE) Consortium

BACKGROUND

This study evaluated whether demographics, pre-diagnosis lifestyle habits and clinical data are associated with the overall survival (OS) and head and neck cancer (HNC)-specific survival in patients with HNC.

PATIENTS AND METHODS

We conducted a pooled analysis, including 4759 HNC patients from five studies within the International Head and Neck Cancer Epidemiology (INHANCE) Consortium. Cox proportional hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) were estimated including terms reported significantly associated with the survival in the univariate analysis.

RESULTS

Five-year OS was 51.4% for all HNC sites combined: 50.3% for oral cavity, 41.1% for oropharynx, 35.0% for hypopharynx and 63.9% for larynx. When we considered HNC-specific survival, 5-year survival rates were 57.4% for all HNC combined: 54.6% for oral cavity, 45.4% for oropharynx, 37.1% for hypopharynx and 72.3% for larynx. Older ages at diagnosis and advanced tumour staging were unfavourable predictors of OS and HNC-specific survival. In laryngeal cancer, low educational level was an unfavourable prognostic factor for OS (HR = 2.54, 95% CI 1.01-6.38, for high school or lower versus college graduate), and status and intensity of alcohol drinking were prognostic factors both of the OS (current drinkers HR = 1.73, 95% CI 1.16-2.58) and HNC-specific survival (current drinkers HR = 2.11, 95% CI 1.22-3.66). In oropharyngeal cancer, smoking status was an independent prognostic factors for OS. Smoking intensity (>20 cigarettes/day HR = 1.41, 95% CI 1.03-1.92) was also an independent prognostic factor for OS in patients with cancer of the oral cavity.

CONCLUSIONS

OS and HNC-specific survival differ among HNC sites. Pre-diagnosis cigarette smoking is a prognostic factor of the OS for patients with cancer of the oral cavity and oropharynx, whereas pre-diagnosis alcohol drinking is a prognostic factor of OS and HNC-specific survival for patients with cancer of the larynx. Low educational level is an unfavourable prognostic factor for OS in laryngeal cancer patients.

Problems in diagnosis and management of desmoid tumors

Thirty-two primary desmoid tumors occurred in 29 patients. The median patient age was 32 years, and 55% of the patients were females. An antecedent history of trauma at the tumor site was elicited from 28% of patients. Thirty-one of 32 primary tumors were completely excised at initial presentation. Five tumors were treated with adjuvant radiotherapy. The overall recurrence rate for primary and recurrent lesions was 60%. The recurrence rate in children (88%) was more than twice that found in adults (38%). A single recurrence did not significantly increase the likelihood of a subsequent recurrence. Greater than 90% of all recurrences took place within 3 years of treatment. The rate of recurrence was not clearly influenced by the status of histologic margins, although this was examined in less than half the tumors. Desmoid tumors are aggressive neoplasms that exhibit a strong propensity for local recurrence. They should be treated as low-grade malignancies with documentation of histologic margins and close clinical follow-up within the framework of a tumor registry.

The EMBL Nucleotide Sequence Database

The EMBL Nucleotide Sequence Database (http://www.ebi.ac.uk/embl.html) constitutes Europe's primary nucleotide sequence resource. Main sources for DNA and RNA sequences are direct submissions from individual researchers, genome sequencing projects and patent applications. While automatic procedures allow incorporation of sequence data from large-scale genome sequencing centres and from the European Patent Office (EPO), the preferred submission tool for individual submitters is Webin (WWW). Through all stages, dataflow is monitored by EBI biologists communicating with the sequencing groups. In collaboration with DDBJ and GenBank the database is produced, maintained and distributed at the European Bioinformatics Institute (EBI). Database releases are produced quarterly and are distributed on CD-ROM. Network services allow access to the most up-to-date data collection via Internet and World Wide Web interface. EBI's Sequence Retrieval System (SRS) is a Network Browser for Databanks in Molecular Biology, integrating and linking the main nucleotide and protein databases, plus many specialised databases. For sequence similarity searching a variety of tools (e.g. Blitz, Fasta, Blast etc) are available for external users to compare their own sequences against the most currently available data in the EMBL Nucleotide Sequence Database and SWISS-PROT.

Size-dependent optical properties of VO2 nanoparticle arrays

The size effects on the optical properties of vanadium dioxide nanoparticles in ordered arrays have been studied. Contrary to previous VO2 studies, we observe that the optical contrast between the semiconducting and metallic phases is dramatically enhanced in the visible region, presenting size-dependent optical resonances and size-dependent transition temperatures. The collective optical response as a function of temperature presents an enhanced scattering state during the evolving phase transition. The effects appear to arise because of the underlying VO2 mesoscale optical properties, the heterogeneous nucleation behind the phase transition, and the incoherent coupling between the nanoparticles undergoing an order-disorder-order transition. Calculations that support these interpretations are presented.

The EMBL nucleotide sequence database

The EMBL Nucleotide Sequence Database (http://www.ebi.ac.uk/embl/) is maintained at the European Bioinformatics Institute (EBI) in an international collaboration with the DNA Data Bank of Japan (DDBJ) and GenBank at the NCBI (USA). Data is exchanged amongst the collaborating databases on a daily basis. The major contributors to the EMBL database are individual authors and genome project groups. Webin is the preferred web-based submission system for individual submitters, whilst automatic procedures allow incorporation of sequence data from large-scale genome sequencing centres and from the European Patent Office (EPO). Database releases are produced quarterly. Network services allow free access to the most up-to-date data collection via ftp, email and World Wide Web interfaces. EBI's Sequence Retrieval System (SRS), a network browser for databanks in molecular biology, integrates and links the main nucleotide and protein databases plus many specialized databases. For sequence similarity searching a variety of tools (e.g. Blitz, Fasta, BLAST) are available which allow external users to compare their own sequences against the latest data in the EMBL Nucleotide Sequence Database and SWISS-PROT.

Value of electrocardiogram in predicting and estimating infarct size in man

The value of the electrocardiogram in assessing infarct size was studied using serial estimates of the MB isomer of creatine kinase (CK MB) in plasma, serial 35 lead praecordial maps in 28 patients with anterior myocardial infarction, and serial 12 lead electrocardiograms in 17 patients with inferior myocardial infarction. In patients with anterior infarcts, sigma ST, sigma R, sigma Q, sigma R/(Q+S), and the number of sites with ST elevation more than 2 mm or with QS waves, were obtained from each map. Correlation between both maximum sigma Q and maximum sigma ST with cumulative CK MB was highly significant. There was also a significant correlation between sigma R and sigma R/(Q+S) with cumulative CK MB. There was no significant correlation between maximum number of sites with ST elevation or with Q or QS waves and cumulative CK MB. Maximum sigma ST and number of sites with ST elevation predicted maximum sigma Q and number of sites with QS or Q waves at a time when infarction was not complete. In patients with inferior infarcts, there was a significant correlation between maximum sigma Q and maximum sigma ST in leads II, III, and a VF, and cumulative CK MB. This study shows that all the waves in the electrocardiogram are useful in assessing infarct size. The fact that maximum sigma ST predicts final sigma Q may be used to assess the efficacy of interventions designed to salvage ischaemic myocardium.

Structural requirements of choline derivatives for 'conversion' of pneumococcal amidase. A new single-step procedure for purification of this autolysin

Tertiary amines appear to be the minimal structure needed to convert in vitro the inactive form (E-form) of pneumococcal amidase to the catalytic active form (C-form). Diethylethanolamine was one of the compounds that converted the E-form, a finding that has been used successfully to develop an affinity chromatography system in DEAE-cellulose for the rapid and efficient purification of lytic enzymes of pneumococcus and its bacteriophages.

Ex vivo expanded human Vgamma9Vdelta2+ gammadelta-T cells mediate innate antitumor activity against human prostate cancer cells in vitro

PURPOSE

We have previously identified a CD2 mediated, interleukin-12 dependent signaling pathway that inhibits activation induced cell death in mitogen stimulated human gammadelta-T cells, permitting the large-scale expansion of these cells. Herein we report the innate antitumor activity of expanded human Vgamma9Vdelta2+ gammadelta-T cells against human prostate cancer cells.

MATERIALS AND METHODS

Apoptosis resistant human gammadelta-T cells were expanded in vitro from cultured human peripheral blood mononuclear cells and then enriched to high purity by immunomagnetic separation. In vitro cytotoxicity of expanded gammadelta-T cells was measured against human prostate cancer cell lines using standard cytotoxicity assays.

RESULTS

gammadelta-T cells derived from various donors consistently showed lytic activity against the prostate cancer cell lines DU-145 and PC-3 but not LNCaP. mAbs against Vgamma9 or Vdelta2 T-cell receptor chains as well as mAb against intercellular adhesion molecule-1 (ICAM-1) or CD18, the beta subunit of ICAM-1 counter receptors, blocked gammadelta-T cell mediated killing of prostate cancer cells. gammadelta-T cells lysed prostate cancer cell lines largely through the perforin/granzyme pathway.

CONCLUSIONS

Ex vivo, expanded human Vgamma9Vdelta2+ gammadelta-T cells are able innately to recognize and kill certain human prostate tumor cell lines in vitro. The recognition and killing of prostate cancer cells occurs in a gammadelta-T-cell receptor dependent manner and it also appears to involve interactions between ICAM-1 and CD18. Because apoptosis resistant human Vgamma9Vdelta2+ gammadelta-T cells can readily be expanded to large numbers (clinical scale), these findings must be considered in the context of developing adoptive immunotherapy strategies to exploit gammadelta-T cell innate immune responses to prostate cancer.

Protection of cardiac membrane phospholipid against oxidative injury by calcium antagonists

Calcium antagonists representative of the four major chemical classes were assessed for their abilities to prevent peroxidation of rat heart membrane lipids through xanthine oxidase-dependent, superoxide-driven, iron-promoted oxygen radical chemistry. The dihydropyridines nifedipine and nitrendipine did not affect peroxidation, even at a concentration (500 microM) approaching their solubility limit. The benzothiazepine diltiazem did protect the cardiac lipids against oxidative injury, but at high micromolar concentrations: 50% inhibition of peroxidation (antiperoxidant IC50) required 510 microM diltiazem. The phenylalkylamines verapamil and gallopamil (D-600) were likewise weak antiperoxidants (approximately 35% inhibition of peroxidation at 500 microM). In contrast, two other alkylamines, bepridil and prenylamine, were very effective membrane lipid protectants with respective antiperoxidant IC50 values of 55 and 75 microM. The diphenylpiperazines flunarizine (IC50 = 190 microM) and cinnarizine (IC50 = 180 microM) displayed moderate antiperoxidant activity. No Ca2+ antagonist inhibited xanthine oxidase under conditions whereby 10 microM allopurinol inhibited enzyme activity by 50%. The effects of the Ca2+ antagonist-antiperoxidants on the kinetics of cardiac membrane lipid peroxidation indicate that they inhibit peroxidation by intercepting oxy- and/or lipid free radical intermediates. These data raise the possibility that antiperoxidant action may contribute to the spectrum of pharmacologic and therapeutic activities of certain Ca2+ antagonists.

Distribution of domestic triatominae and stratification of Chagas Disease transmission in Oaxaca, Mexico

Mexico has 18 species of Triatomine bugs (Hemiptera: Reduviidae) reported to be vectors of Trypanosoma cruzi. Chagas Disease is widespread in Mexico, with up to 3.5% seropositivity of human transfusion blood. The State of Oaxaca has the longest history of endemic Chagas Disease, based on acute and chronic case reports, and of entomological surveys in the country. However, the State health care services need more information on current risks of vector transmission. In order to identify and characterize areas of transmission in Oaxaca and to stratify the vector potential, the distribution of domestic Triatominae was surveyed during 1996-98 in collaboration with the primary health care services and local communities. Villages were studied in 11% of 570 municipalities in Oaxaca. Eight triatomine species were found in domestic and peri-domestic habitats: Triatoma barberi Usinger, T. bolivari Carcavallo et al., T. dimidiata (Latreille), T. mazzottii Usinger, T. nitida Usinger, T. pallidipennis (Stal), T. phyllosoma (Burmeister) and Rhodnius prolixus Stal. For each triatomine species in Oaxaca, the range of distribution and habitat characteristics are described. Habitat partitioning, principally based on altitude and mean annual precipitation, limited the overlap of distribution between species. Relatively consistent altitude of human settlements facilitates the dispersion of individual species within microregions. Entomological indices of house infestation were used to estimate that approximately 50% of the human population (1,874,320 inhabitants) would be at risk of vector transmission, with a minimum of 134,320 infected people and 40,280 chronic cases of Chagas Disease currently in Oaxaca.

Administration of adalimumab in the treatment of Crohn's disease of the ileal pouch

BACKGROUND

Crohn's disease (CD) of the pouch can develop in patients with ileal pouch-anal anastomosis (IPAA). Scant data are available on the treatment of this disease entity.

AIM

To evaluate efficacy and safety of adalimumab in treating CD of the ileal pouch.

METHODS

From June 2007 to June 2008, 17 IPAA patients with inflammatory (n = 10), fibrostenotic (n = 2) or fistulizing (n = 5) CD of the pouch treated with adalimumab were evaluated. Inclusion criteria were CD of the pouch who failed medical therapy and were otherwise qualified for permanent pouch diversion or excision. All qualified patients received the standard dosing regimen of subcutaneous injection adalimumab (160 mg at week 0, 80 mg at week 1, and 40 mg every other week thereafter). Complete clinical response was defined as resolution of symptoms. Partial clinical response was defined as improvement in symptoms. Endoscopic inflammation before and after therapy was recorded, using the Pouchitis Disease Activity Index (PDAI) endoscopy subscores.

RESULTS

The median age was 36 years with 12 patients (70.6%) being male. At 4 weeks, seven patients (41.2%) had a complete symptom response and 6 (35.3%) had a partial response. There was also a significant improvement in the PDAI endoscopy subscores at week 4 (P < 0.05). At the last follow-up (median of 8 weeks), eight patients (47.1%) had a complete symptom response and 4 (23.5%) had a partial response. Four patients (23.6%) developed adverse effects. Three patients (17.7%) eventually had pouch failure after failing to respond to adalimumab therapy.

CONCLUSION

Adalimumab appeared to be well-tolerated and efficacious in treating CD of the pouch in this open-labelled induction study.

Characterization and immunotherapeutic potential of gammadelta T-cells in patients with glioblastoma

Classical immunotherapeutic approaches to glioblastoma multiforme (GBM) have shown mixed results, and therapies focused on innate lymphocyte activity against GBM have not been rigorously evaluated. We examined peripheral blood lymphocyte phenotype, gammadelta T-cell number, mitogenic response, and cytotoxicity against GBM cell lines and primary tumor explants from GBM patients at selected time points prior to and during GBM therapy. Healthy volunteers served as controls and were grouped by age. T-cell infiltration of tumors from these patients was assessed by staining for CD3 and T-cell receptor gammadelta. Our findings revealed no differences in counts of mean absolute T-cells, T-cell subsets CD3+CD4+ and CD3+CD8+, and natural killer cells from healthy volunteers and patients prior to and immediately after GBM resection. In contrast, gammadelta T-cell counts and mitogen-stimulated proliferative response of gammadelta T-cells were markedly decreased prior to GBM resection and throughout therapy. Expanded/activated gammadelta T-cells from both patients and healthy volunteers kill GBM cell lines D54, U373, and U251, as well as primary GBM, without cytotoxicity to primary astrocyte cultures. Perivascular T-cell accumulation was noted in paraffin sections, but no organized T-cell invasion of the tumor parenchyma was seen. Taken together, these data suggest that gammadelta T-cell depletion and impaired function occur prior to or concurrent with the growth of the tumor. The significant cytotoxicity of expanded/activated gammadelta T-cells from both healthy controls and selected patients against primary GBM explants may open a previously unexplored approach to cellular immunotherapy of GBM.

gammadelta T cells: a new frontier for immunotherapy?

The use of cytolytic effector cells as therapy for malignant disease has been a central focus of basic and clinical research for nearly 2 decades. Since the original descriptions of in vitro lymphocyte-mediated cytotoxicity against human tumor cells, there have been numerous attempts to exploit such observations for therapeutic use, with decidedly mixed results. Most studies have focused on the role of either natural killer cells or cytotoxic CD8 + alphabeta T cells as the primary mediators of antitumor cytotoxicity, and until recently little attention has been paid to the role of gammadelta T cells in this capacity. This is partially due to a lack of understanding of the mechanisms of gammadelta T-cell immune responses to tumors, as well as the practical problem of obtaining a sufficient number of gammadelta T cells for clinical-scale administration. In this article, we discuss the biological and clinical rationale for developing gammadelta T cell-based immunotherapies for the treatment of a variety of malignant conditions. It is our view that infusing supraphysiological numbers of tumor-reactive gammadelta T cells-either in the autologous or allogeneic setting-might be used to restore or augment innate immune responses against malignancies. Accordingly, we will also discuss how we and others are working to overcome some of the practical limitations that have so far limited the direct clinical delivery of highly purified human gammadelta T cells for the treatment of both hematologic and solid tumors.