[Digitalization and clinical decision tools]. / Digitalisierung und Clinical Decision Tools.

Digitalization in cardiovascular emergencies is rapidly evolving, analogous to the development in medicine, driven by the increasingly broader availability of digital structures and improved networks, electronic health records and the interconnectivity of systems. The potential use of digital health in patients with acute chest pain starts even in the prehospital phase with the transmission of a digital electrocardiogram (ECG) as well as telemedical support and digital emergency management, which facilitate optimization of the rescue pathways and reduce critical time intervals. The increasing dissemination and acceptance of guideline apps and clinical decision support tools as well as integrated calculators and electronic scores are anticipated to improve guideline adherence, translating into a better quality of treatment and improved outcomes. Implementation of artificial intelligence to support image analysis and also the prediction of coronary artery stenosis requiring interventional treatment or impending cardiovascular events, such as heart attacks or death, have an enormous potential especially as conventional instruments frequently yield suboptimal results; however, there are barriers to the rapid dissemination of corresponding decision aids, such as the regulatory rules related to approval as a medical product, data protection issues and other legal liability aspects, which must be considered.

Practical setting and potential applications of interventions guided by PET/MRI.

Multimodality imaging has emerged from a vision thirty years ago to routine clinical use today. Positron emission tomography (PET)/magnetic resonance imaging (MRI) is still relatively new in this arena and particularly suitable for clinical research and technical development. PET/MRI-guidance for interventions opens up opportunities for novel treatments but at the same time demands certain technical and organizational requirements to be fulfilled. In this work, we aimed to demonstrate a practical setting and potential application of PET/MRI guidance of interventional procedures. The superior quantitative physiologic information of PET, the various unique imaging characteristics of MRI, and the reduced radiation exposure are the most relevant advantages of this technique. As a noninvasive interventional tool, focused ultrasound (FUS) ablation of tumor cells would benefit from PET/MRI for diagnostics, treatment planning and intervention. Yet, technical limitations might impeed preclinical research, given that PET/MRI sites are per se not designed as interventional suites. Nonetheless, several approaches have been offered in the past years to upgrade MRI suites for interventional purposes. Taking advantage of state of the art and easy-to-use technology it is possible to create a supporting infrastructure that is suitable for broad preclinical adaption. Several aspects are to be addressed, including remote control of the imaging system, display of the imaging results, communication technology, and implementation of additional devices such as a FUS platform and an MR-compatible robotic system for positioning of the FUS equipment. Feasibility could be demostrated with an examplary experimental setup for interventional PET/MRI. Most PET/MRI sites could allow for interventions with just a few add-ons and modifications, such as comunication, in room image display and sytems control. By unlocking this feature, and driving preclinical research in interventional PET/MRI, translation of the protocol and methodology into clinical settings seems feasible.

Optimizing genomic prediction for Australian Red dairy cattle.

The reliability of genomic prediction is influenced by several factors, including the size of the reference population, which makes genomic prediction for breeds with a relatively small population size challenging, such as Australian Red dairy cattle. Including other breeds in the reference population may help to increase the size of the reference population, but the reliability of genomic prediction is also influenced by the relatedness between the reference and validation population. Our objective was to optimize the reference population for genomic prediction of Australian Red dairy cattle. A reference population comprising up to 3,248 Holstein bulls, 48,386 Holstein cows, 807 Jersey bulls, 8,734 Jersey cows, and 3,041 Australian Red cows and a validation population with between 208 and 224 Australian Red Bulls were used, with records for milk, fat, and protein yield, somatic cell count, fertility, and survival. Three different analyses were implemented: single-trait genomic best linear unbiased predictor (GBLUP), multi-trait GBLUP, and single-trait Bayes R, using 2 different medium-density SNP panels: the standard 50K chip and a custom array of variants that were expected to be enriched for causative mutations. Various reference populations were constructed containing the Australian Red cows and all Holstein and Jersey bulls and cows, all Holstein and Jersey bulls, all Holstein bulls and cows, all Holstein bulls, and a subset of the Holstein individuals varying the relatedness between Holsteins and Australian Reds and the number of Holsteins. Varying the relatedness between reference and validation populations only led to small changes in reliability. Whereas adding a limited number of closely related Holsteins increased reliabilities compared with within-breed prediction, increasing the number of Holsteins decreased the reliability. The multi-trait GBLUP, which considered the same trait in different breeds as correlated traits, yielded higher reliabilities than the single-trait GBLUP. Bayes R yielded lower reliabilities than multi-trait GBLUP and outperformed single-trait GBLUP for larger reference populations. Our results show that increasing the size of a multi-breed reference population may result in a reference population dominated by one breed and reduce the reliability to predict in other breeds.

Fractal morphology, imaging and mass spectrometry of single aerosol particles in flight.

The morphology of micrometre-size particulate matter is of critical importance in fields ranging from toxicology to climate science, yet these properties are surprisingly difficult to measure in the particles' native environment. Electron microscopy requires collection of particles on a substrate; visible light scattering provides insufficient resolution; and X-ray synchrotron studies have been limited to ensembles of particles. Here we demonstrate an in situ method for imaging individual sub-micrometre particles to nanometre resolution in their native environment, using intense, coherent X-ray pulses from the Linac Coherent Light Source free-electron laser. We introduced individual aerosol particles into the pulsed X-ray beam, which is sufficiently intense that diffraction from individual particles can be measured for morphological analysis. At the same time, ion fragments ejected from the beam were analysed using mass spectrometry, to determine the composition of single aerosol particles. Our results show the extent of internal dilation symmetry of individual soot particles subject to non-equilibrium aggregation, and the surprisingly large variability in their fractal dimensions. More broadly, our methods can be extended to resolve both static and dynamic morphology of general ensembles of disordered particles. Such general morphology has implications in topics such as solvent accessibilities in proteins, vibrational energy transfer by the hydrodynamic interaction of amino acids, and large-scale production of nanoscale structures by flame synthesis.

Polyceraty (multi-horns) in Damara sheep maps to ovine chromosome 2.

Polyceraty (presence of multiple horns) is rare in modern day ungulates. Although not found in wild sheep, polyceraty does occur in a small number of domestic sheep breeds covering a wide geographical region. Damara are fat-tailed hair sheep, from the south-western region of Africa, which display polyceraty, with horn number ranging from zero to four. We conducted a genome-wide association study for horn number with 43 Damara genotyped with 606 006 SNP markers. The analysis revealed a region with multiple significant SNPs on ovine chromosome 2, in a location different from the mutation for polled in sheep on chromosome 10. The causal mutation for polyceraty was not identified; however, the region associated with polyceraty spans nine HOXD genes, which are critical in embryonic development of appendages. Mutations in HOXD genes are implicated in polydactly phenotypes in mice and humans. There was no evidence for epistatic interactions contributing to polyceraty. This is the first report on the genetic mechanisms underlying polyceraty in the under-studied Damara.

DCE-MRI of the breast in a stand-alone setting outside a complementary strategy - results of the TK-study.

OBJECTIVES: To evaluate the accuracy of MRI of the breast (DCE-MRI) in a stand-alone setting with extended indications. MATERIALS AND METHODS: According to the inclusion criteria, breast specialists were invited to refer patients to our institution for DCE-MRI. Depending on the MR findings, patients received either a follow-up or biopsy. Between 04/2006 and 12/2011 a consecutive total of 1,488 women were prospectively examined. RESULTS: Of 1,488 included patients, 393 patients were lost to follow-up, 1,095 patients were evaluated. 124 patients were diagnosed with malignancy by DCE-MRI (76 TP, 48 FP, 971 TN, 0 FN cases). Positive cases were confirmed by histology, negative cases by MR follow-ups or patient questionnaires over the next 5 years in 1,737 cases (sensitivity 100 %; specificity 95.2 %; PPV 61.3 %; NPV 100 %; accuracy 95.5 %). For invasive cancers only (DCIS excluded), the results were 63 TP; 27 FP; 971 TP and 0 FN (sensitivity 100 %; specificity 97.2 %; PPV 70 %; NPV 100 %; accuracy 97.5 %). CONCLUSION: The DCE-MRI indications tested imply that negative results in DCE-MRI reliably exclude cancer. The results were achieved in a stand-alone setting (single modality diagnosis). However, these results are strongly dependent on reader experience and adequate technical standards as prerequisites for optimal diagnoses. KEY POINTS: • DCE-MRI of the breast has a high accuracy in finding breast cancer. • The set of indications for DCE-MRI of the breast is still very limited. • DCE-MRI can achieve a high accuracy in a 'screening-like' setting. • Accuracy of breast DCE-MRI is strongly dependent on technique and reader experience. • A negative DCE-MRI effectively excludes cancer.

Tensile Ge microstructures for lasing fabricated by means of a silicon complementary metal-oxide-semiconductor process.

In this work we study, using experiments and theoretical modeling, the mechanical and optical properties of tensile strained Ge microstructures directly fabricated in a state-of-the art complementary metal-oxide-semiconductor fabrication line, using fully qualified materials and methods. We show that these microstructures can be used as active lasing materials in mm-long Fabry-Perot cavities, taking advantage of strain-enhanced direct band gap recombination. The results of our study can be realistically applied to the fabrication of a prototype platform for monolithic integration of near infrared laser sources for silicon photonics.

Femtosecond dark-field imaging with an X-ray free electron laser.

The emergence of femtosecond diffractive imaging with X-ray lasers has enabled pioneering structural studies of isolated particles, such as viruses, at nanometer length scales. However, the issue of missing low frequency data significantly limits the potential of X-ray lasers to reveal sub-nanometer details of micrometer-sized samples. We have developed a new technique of dark-field coherent diffractive imaging to simultaneously overcome the missing data issue and enable us to harness the unique contrast mechanisms available in dark-field microscopy. Images of airborne particulate matter (soot) up to two microns in length were obtained using single-shot diffraction patterns obtained at the Linac Coherent Light Source, four times the size of objects previously imaged in similar experiments. This technique opens the door to femtosecond diffractive imaging of a wide range of micrometer-sized materials that exhibit irreproducible complexity down to the nanoscale, including airborne particulate matter, small cells, bacteria and gold-labeled biological samples.

Nanoplasma dynamics of single large xenon clusters irradiated with superintense x-ray pulses from the linac coherent light source free-electron laser.

The plasma dynamics of single mesoscopic Xe particles irradiated with intense femtosecond x-ray pulses exceeding 10(16) W/cm2 from the Linac Coherent Light Source free-electron laser are investigated. Simultaneous recording of diffraction patterns and ion spectra allows eliminating the influence of the laser focal volume intensity and particle size distribution. The data show that for clusters illuminated with intense x-ray pulses, highly charged ionization fragments in a narrow distribution are created and that the nanoplasma recombination is efficiently suppressed.

Improving accuracy of genomic predictions within and between dairy cattle breeds with imputed high-density single nucleotide polymorphism panels.

Achieving accurate genomic estimated breeding values for dairy cattle requires a very large reference population of genotyped and phenotyped individuals. Assembling such reference populations has been achieved for breeds such as Holstein, but is challenging for breeds with fewer individuals. An alternative is to use a multi-breed reference population, such that smaller breeds gain some advantage in accuracy of genomic estimated breeding values (GEBV) from information from larger breeds. However, this requires that marker-quantitative trait loci associations persist across breeds. Here, we assessed the gain in accuracy of GEBV in Jersey cattle as a result of using a combined Holstein and Jersey reference population, with either 39,745 or 624,213 single nucleotide polymorphism (SNP) markers. The surrogate used for accuracy was the correlation of GEBV with daughter trait deviations in a validation population. Two methods were used to predict breeding values, either a genomic BLUP (GBLUP_mod), or a new method, BayesR, which used a mixture of normal distributions as the prior for SNP effects, including one distribution that set SNP effects to zero. The GBLUP_mod method scaled both the genomic relationship matrix and the additive relationship matrix to a base at the time the breeds diverged, and regressed the genomic relationship matrix to account for sampling errors in estimating relationship coefficients due to a finite number of markers, before combining the 2 matrices. Although these modifications did result in less biased breeding values for Jerseys compared with an unmodified genomic relationship matrix, BayesR gave the highest accuracies of GEBV for the 3 traits investigated (milk yield, fat yield, and protein yield), with an average increase in accuracy compared with GBLUP_mod across the 3 traits of 0.05 for both Jerseys and Holsteins. The advantage was limited for either Jerseys or Holsteins in using 624,213 SNP rather than 39,745 SNP (0.01 for Holsteins and 0.03 for Jerseys, averaged across traits). Even this limited and nonsignificant advantage was only observed when BayesR was used. An alternative panel, which extracted the SNP in the transcribed part of the bovine genome from the 624,213 SNP panel (to give 58,532 SNP), performed better, with an increase in accuracy of 0.03 for Jerseys across traits. This panel captures much of the increased genomic content of the 624,213 SNP panel, with the advantage of a greatly reduced number of SNP effects to estimate. Taken together, using this panel, a combined breed reference and using BayesR rather than GBLUP_mod increased the accuracy of GEBV in Jerseys from 0.43 to 0.52, averaged across the 3 traits.

Design and validation of a medical robotic device system to control two collaborative robots for ultrasound-guided needle insertions.

The percutaneous biopsy is a critical intervention for diagnosis and staging in cancer therapy. Robotic systems can improve the efficiency and outcome of such procedures while alleviating stress for physicians and patients. However, the high complexity of operation and the limited possibilities for robotic integration in the operating room (OR) decrease user acceptance and the number of deployed robots. Collaborative systems and standardized device communication may provide approaches to overcome named problems. Derived from the IEEE 11073 SDC standard terminology of medical device systems, we designed and validated a medical robotic device system (MERODES) to access and control a collaborative setup of two KUKA robots for ultrasound-guided needle insertions. The system is based on a novel standard for service-oriented device connectivity and utilizes collaborative principles to enhance user experience. Implementing separated workflow applications allows for a flexible system setup and configuration. The system was validated in three separate test scenarios to measure accuracies for 1) co-registration, 2) needle target planning in a water bath and 3) in an abdominal phantom. The co-registration accuracy averaged 0.94 ± 0.42 mm. The positioning errors ranged from 0.86 ± 0.42 to 1.19 ± 0.70 mm in the water bath setup and from 1.69 ± 0.92 to 1.96 ± 0.86 mm in the phantom. The presented results serve as a proof-of-concept and add to the current state of the art to alleviate system deployment and fast configuration for percutaneous robotic interventions.

Hydrolyzed fish collagen induced chondrogenic differentiation of equine adipose tissue-derived stromal cells.

Adipose-derived stromal cells (ADSCs) are multipotent cells which, in the presence of appropriate stimuli, can differentiate into various lineages such as the osteogenic, adipogenic and chondrogenic. In this study, we investigated the effect of transforming growth factor beta 1 (TGF-ß1) in comparison to hydrolyzed fish collagen in terms of the chondrogenic differentiation potential of ADSCs. ADSCs were isolated from subcutaneous fat of horses by liposuction. Chondrogenesis was investigated using a pellet culture system. The differentiation medium was either supplemented with TGF-ß1 (5 ng/ml) or fish collagen (0.5 mg/ml) for a 3 week period. After the 3 weeks in vitro differentiation, RT-PCR and histological staining for proteoglycan synthesis and type II collagen were performed to evaluate the degree of chondrogenic differentiation and the formation of cartilaginous extracellular matrix (ECM). The differentiation of ADSCs induced by TGF-ß1 showed a high expression of glycosaminoglycan (GAG). Histological analysis of cultures stimulated by hydrolyzed fish collagen demonstrated an even higher GAG expression than cultures stimulated under standard conditions by TGF-ß1. The expression of cartilage-specific type II collagen and Sox9 was about the same in both stimulated cultures. In this study, chondrogenesis was as effectively induced by hydrolyzed fish collagen as it was successfully induced by TGF-ß1. These findings demonstrated that hydrolyzed fish collagen alone has the potential to induce and maintain ADSCs-derived chondrogenesis. These results support the application of ADSCs in equine veterinary tissue engineering, especially for cartilage repair.

Repetitions of fundamental research models for homeopathically prepared dilutions beyond 10(-23): a bibliometric study.

INTRODUCTION: Repeatability of experiments is an important criterion of modern research and a major challenge for homeopathic basic research. There is no recent overview about basic research studies in high homeopathic potencies that have been subjected to laboratory-internal, multicenter or independent repetition trials. METHODS: We considered biochemical, immunological, botanical, cell biological and zoological studies on high potencies, i.e. beyond a dilution of 10(-23). Main sources of information were reviews, personal contact with members of the homeopathic basic research community, and the MEDLINE and HOMBREX databases. Studies were extracted from the publications and grouped into models. Studies were further sorted according to repetition type (laboratory-internal, multicenter, or independent) and results achieved. RESULTS: A total of 107 studies were found. Of these, 30 were initial studies. In the attempt to reproduce one of these initial studies, 53 follow-up studies yielded comparable effects (35 laboratory-internal, 8 multicenter, 10 independent repetitions), eight studies showed a consistent, yet different result from the initial study (2 laboratory-internal, 2 multicenter, 4 independent repetitions), and 16 studies yielded no effects (5 laboratory-internal, 2 multicenter, 9 independent repetitions). When all repetitive studies are considered, 69% reported effects comparable to that of the initial study, 10% different effects, and 21% no effects. Independently performed repetition studies reported 44% comparable effects, 17% different effects, and 39% no effects. CONCLUSIONS: We identified 24 experimental models in basic research on high homeopathic potencies, which were repeatedly investigated. 22 models were reproduced with comparable results, 6 models with different results, and repetition showed no results for 15 models. Independent reproductions with either comparable or different results were found for seven models. We encourage further repetition trials of published studies, in order to learn more about the model systems used and in order to test their repeatability.

Role of the protein moiety of ribonuclease P, a ribonucleoprotein enzyme.

The Bacillus subtilis ribonuclease P consists of a protein and an RNA. At high ionic strength the reaction is protein-independent; the RNA alone is capable of cleaving precursor transfer RNA, but the turnover is slow. Kinetic analyses show that high salt concentrations facilitate substrate binding in the absence of the protein, probably by decreasing the repulsion between the polyanionic enzyme and substrate RNAs, and also slow product release and enzyme turnover. It is proposed that the ribonuclease P protein, which is small and basic, provides a local pool of counter-ions that facilitates substrate binding without interfering with rapid product release.

Complete genome sequence of the methanogenic archaeon, Methanococcus jannaschii.

The complete 1.66-megabase pair genome sequence of an autotrophic archaeon, Methanococcus jannaschii, and its 58- and 16-kilobase pair extrachromosomal elements have been determined by whole-genome random sequencing. A total of 1738 predicted protein-coding genes were identified; however, only a minority of these (38 percent) could be assigned a putative cellular role with high confidence. Although the majority of genes related to energy production, cell division, and metabolism in M. jannaschii are most similar to those found in Bacteria, most of the genes involved in transcription, translation, and replication in M. jannaschii are more similar to those found in Eukaryotes.

[Does dilution have an impact on cosmetic results with BoNT/A? Complex-protein-free BoNT/A for treatment of glabella lines]. / Beeinflusst die Verdünnung das kosmetische Ergebnis von BoNT/A? Komplexproteinfreies BoNT/A zur Behandlung der Glabellafalte.

BACKGROUND: In this 2-armed, randomized study we investigated the efficacy and tolerability of complex-protein-free botulinum neurotoxin type A (BoNT/A), applied in two different dilution volumes for treatment of glabellar lines. PATIENTS AND METHODS: 40 patients with grade 2-3 glabellar lines (Facial Wrinkle Scale) received treatment with 25U BoNT/A (Xeomin). 100U of botulinum neurotoxin were diluted in 2.5 ml (group I) or 4 ml sodium chloride solution (group II). Responders showed an improvement in the wrinkle score (independent rater) of at least one point. RESULTS. Response rates two weeks after treatment were 100% / 89.5%, at 3 months 84.2% / 64.7% and at 4 months 53.3% / 61.5% (groups I / II respectively). There was no significant difference between the two dilutions. CONCLUSION: Complex-protein-free botulinum neurotoxin type A in both dilutions effectively reduced severity of glabellar lines. There was no statistically significant difference in efficacy between the two dilutions.

Effect of clinical signs, endocrinopathies, timing of surgery, hyperlipidemia, and hyperbilirubinemia on outcome in dogs with gallbladder mucocele.

Gallbladder mucocele (GBM) is a common extra-hepatic biliary syndrome in dogs with death rates ranging from 7 to 45%. Therefore, the aim of this study was to identify the association of survival with variables that could be utilized to improve clinical decisions. A total of 1194 dogs with a gross and histopathological diagnosis of GBM were included from 41 veterinary referral hospitals in this retrospective study. Dogs with GBM that demonstrated abnormal clinical signs had significantly greater odds of death than subclinical dogs in a univariable analysis (OR, 4.2; 95% CI, 2.14-8.23; P<0.001). The multivariable model indicated that categorical variables including owner recognition of jaundice (OR, 2.12; 95% CI, 1.19-3.77; P=0.011), concurrent hyperadrenocorticism (OR 1.94; 95% CI, 1.08-3.47; P=0.026), and Pomeranian breed (OR, 2.46; 95% CI 1.10-5.50; P=0.029) were associated with increased odds of death, and vomiting was associated with decreased odds of death (OR, 0.48; 95% CI, 0.30-0.72; P=0.001). Continuous variables in the multivariable model, total serum/plasma bilirubin concentration (OR, 1.03; 95% CI, 1.01-1.04; P<0.001) and age (OR, 1.17; 95% CI, 1.08-1.26; P<0.001), were associated with increased odds of death. The clinical utility of total serum/plasma bilirubin concentration as a biomarker to predict death was poor with a sensitivity of 0.61 (95% CI, 0.54-0.69) and a specificity of 0.63 (95% CI, 0.59-0.66). This study identified several prognostic variables in dogs with GBM including total serum/plasma bilirubin concentration, age, clinical signs, concurrent hyperadrenocorticism, and the Pomeranian breed. The presence of hypothyroidism or diabetes mellitus did not impact outcome in this study.

Endocannabinoid modulation of fear responses: learning and state-dependent performance effects.

Recently, disruption of the endogenous cannabinoid (endocannabinoid, eCB) system was found to impair extinction in delay and contextual fear conditioning models. However, conditioning procedures used in that work precluded investigation of possible eCB effects on acquisition of learned fear. We therefore examined the role of eCBs in modulating fear responses using multiple-trial versions of trace (hippocampal-dependent) and delay (amygdala-dependent) Pavlovian fear conditioning. By administering the CB1 receptor antagonist AM251 (5 mg/kg, i.p) to C57/Bl/6 mice at various times, we systematically identified the stages of learning and memory (i.e. acquisition, consolidation, recall and extinction) that are modulated by eCB signaling. During tone (CS) - footshock (US) conditioning, AM251 enhanced acquisition of freezing behavior for both trace- and delay-conditioning protocols. CB1 antagonism also enhanced generalized fear (baseline freezing) and cued (CS) freezing during memory recall tests in a state-dependent manner for both trace and delay conditioned animals. Furthermore, in trace-conditioned animals, AM251 impaired extinction performance of both cued and generalized fear. CB1 antagonism did not affect short-term memory (STM) or long-term memory (LTM) consolidation processes. Together, these results suggest that during acquisition and recall of aversive learning, eCBs prevent the expression and retention of inappropriate generalized and learned responses. These findings have important implications for the therapeutic use of CB1 antagonists.

Benefit evaluation in vitiligo treatment: development and validation of a patient-defined outcome questionnaire.

BACKGROUND: In addition to clinical efficacy, patient-defined benefit assessment has become an important outcome parameter. Thus far, no such instrument has been developed for vitiligo. OBJECTIVES: Development and validation of a patient-defined benefit questionnaire in the therapy of vitiligo. METHODS: Open questioning of 50 vitiligo patients generated 110 benefit items, which were converted into a 26-item questionnaire by a panel of dermatologists, psychologists and patients. This was used to record patient-defined needs prior to therapy and to evaluate patient benefit attained after therapy. A 'patient benefit index' (PBI) was formed on the basis of both. Validation was based on data of n = 1,023 vitiligo patients. RESULTS: The questionnaires were feasible in clinical practice, Cronbach's alpha (patient need questionnaire) was 0.94. The PBI showed convergent and discriminant validity with respect to quality of life and patient satisfaction. CONCLUSION: The PBI for vitiligo is a valid instrument, which is highly accepted in practice for recording patient-reported benefit.

Activation of human B cells by phosphorothioate oligodeoxynucleotides.

To investigate the potential of DNA to elicit immune responses in man, we examined the capacity of a variety of oligodeoxynucleotides (ODNs) to stimulate highly purified T cell-depleted human peripheral blood B cells. Among 47 ODNs of various sequences tested, 12 phosphorothioate oligodeoxynucleotides (sODNs) induced marked B cell proliferation and Ig production. IL-2 augmented both proliferation and production of IgM, IgG, and IgA, as well as IgM anti-DNA antibodies, but was not necessary for B cell stimulation. Similarly, T cells enhanced stimulation, but were not necessary for B cell activation. After stimulation with the active sODNs, more than 95% of B cells expressed CD25 and CD86. In addition, B cells stimulated with sODNs expressed all six of the major immunoglobulin VH gene families. These results indicate that the human B cell response to sODN is polyclonal. Active sODN coupled to Sepharose beads stimulated B cells as effectively as the free sODN, suggesting that stimulation resulted from engagement of surface receptors. These data indicate that sODNs can directly induce polyclonal activation of human B cells in a T cell-independent manner by engaging as yet unknown B cell surface receptors.