F-doping of nanostructured ZnO: a way to modify structural, electronic, and surface properties.

Polycrystalline ZnO is a material often used in heterogeneous catalysis. Its properties can be altered by the addition of dopants. We used gaseous fluorine (F2(g)) as direct way to incorporate fluoride in ZnO as anionic dopants. Here, the consequences of this treatment on the structural and electronic properties, as well as on the acidic/basic sites of the surface, are investigated. It is shown that the amount of F incorporation into the structure can be controlled by the synthesis parameters (t, T, p). While the surface of ZnO was altered as shown by, e.g., IR spectroscopy, XPS, and STEM/EDX measurements, the F2 treatment also influenced the electronic properties (optical band gap, conductivity) of ZnO. Furthermore, the Lewis acidity/basicity of the surface was affected which is evidenced by using, e.g., different probe molecules (CO2, NH3). In situ investigations of the fluorination process offer valuable insights on the fluorination process itself.

A mutation in VPS35, encoding a subunit of the retromer complex, causes late-onset Parkinson disease.

To identify rare causal variants in late-onset Parkinson disease (PD), we investigated an Austrian family with 16 affected individuals by exome sequencing. We found a missense mutation, c.1858G>A (p.Asp620Asn), in the VPS35 gene in all seven affected family members who are alive. By screening additional PD cases, we saw the same variant cosegregating with the disease in an autosomal-dominant mode with high but incomplete penetrance in two further families with five and ten affected members, respectively. The mean age of onset in the affected individuals was 53 years. Genotyping showed that the shared haplotype extends across 65 kilobases around VPS35. Screening the entire VPS35 coding sequence in an additional 860 cases and 1014 controls revealed six further nonsynonymous missense variants. Three were only present in cases, two were only present in controls, and one was present in cases and controls. The familial mutation p.Asp620Asn and a further variant, c.1570C>T (p.Arg524Trp), detected in a sporadic PD case were predicted to be damaging by sequence-based and molecular-dynamics analyses. VPS35 is a component of the retromer complex and mediates retrograde transport between endosomes and the trans-Golgi network, and it has recently been found to be involved in Alzheimer disease.

[The seriously affected stroke patient who is not able to communicate - treatment to the best of one's knowledge and ethical principles]. / Der schwer betroffene kommunikationsunfähige Schlaganfallpatient - Handeln nach bestem Wissen und ethischen Grundlagen der medizinischen Behandlung?

Choosing the right therapy for a patient affected by a severe stroke that resulted in communicative inability is a real challenge for an interdisciplinary team. In the following case prognostic predictors will be investigated and ethical issues for a better decision making will be discussed.

Optical coherence tomography angiography suggests different retinal pathologies in multiple sclerosis and Sjögren's syndrome.

BACKGROUND: While retinal vessel changes are evident in the eyes of patients with relapsing-remitting multiple sclerosis (RRMS), changes in the vasculature of possible MS mimics such as primary Sjögren's syndrome (pSS) remain to be determined. We investigated the potential of retinal optical coherence tomography (OCT) angiography (OCTA) as diagnostic tool to differentiate between patients with RRMS and pSS. METHODS: This cross-sectional study included patients with RRMS (n = 36), pSS (n = 36) and healthy controls (n = 30). Participants underwent clinical examination, assessment of visual acuity, retinal OCT, OCTA, and serum markers of glial and neuronal damage. We investigated the associations between OCTA parameters, visual functions, and serum markers. Eyes with a history of optic neuritis (ON) were excluded from analysis. RESULTS: We observed a significant thinning of the combined ganglion cell and inner plexiform layer in the eyes of patients with RRMS but not with pSS, when compared to healthy controls. Retinal vessel densities of the superficial vascular complex (SVC) were reduced in both patients with RRMS and pSS. However, retinal vessel rarefication of the deep vascular complex (DVC) was only evident in patients with pSS but not RRMS. Using multivariate regression analysis, we found that DVC vessel loss in pSS patients was associated with worse visual acuity. CONCLUSIONS: Compared to patients with RRMS, rarefication of deep retinal vessels is a unique characteristic of pSS and associated with worse visual function. Assuming a disease-specific retinal vessel pathology, these data are indicative of a differential affliction of the gliovascular complex in the retina of RRMS and pSS patients.

The novel myxofibrosarcoma cell line MUG-Myx1 expresses a tumourigenic stem-like cell population with high aldehyde dehydrogenase 1 activity.

BACKGROUND: Myxofibrosarcoma comprises a spectrum of malignant neoplasms withprominent myxoid stromata, cellular pleomorphism, and distinct curvilinear vascular patterns. These neoplasms mainly affect patients in the sixth to eighth decades of life and the overall 5-year survival rate is 60-70%. METHODS: After the establishment of the novel myxofibrosarcoma cell lines MUG-Myx1, cells were characterized using short tandem repeat (STR), copy number variation (CNV), and genotype/loss-of-heterozygosity (LOH) analyses. The growth behaviour of the cells was analyzed with the xCELLigence system and an MTS assay. The tumourigenicity of MUG-Myx1 was proved in NOD/SCID mice. Additionally, a stem-like cell population with high enzymatic activity of aldehyde dehydrogenase 1 (ALDH1(high)) was isolated for the first time from myxofibrosarcoma cells using the Aldefluor® assay followed by FACS analysis. RESULTS: The frozen primary parental tumour tissue and the MUG-Myx1 cell line showed the same STR profile at the markers D3S1358, TH01, D21S11, D18S51, Penta E, D5S818, D13S317, D7S820, D16S539, CSF1PO, Penta D, Amelogenin, D8S1179, TPOX, and FGY. Typically, myxofibrosarcoma gain and/or amplification was mapped to 7p21.3-q31.1, q31.1-q31.33, q33-q36.2, p21.3, p21.2, p14.1-q11.23, q31.33-q33, p21.2-p14.1, q11.23-q21.3, q36.2-q36.3, which, respectively are known to harbour tumour-associated genes, including TIF, BRAF, MLL3, SMO, and MET. Typically an LOH for myxofibrosarcoma on chr5 q21 was found. In addition, MUG-Myx1 ALDH1(high) cells showed an upregulation of the ABC transporter ABCB1 and ABCG2; higher c-Myc, E-cadherin and SOX-2 expression; and a higher potential for tumourigenicity and proliferation levels. CONCLUSION: The new myxofibrosarcoma cell line MUG-Myx1 was established to enrich the bank of publicly available cell lines, with respect to providing comprehensive genetic and epigenetic characterization. Furthermore, because of their tumourigenicity, the cell line is also suitable for in vivo experiments.

A new rechargeable device for deep brain stimulation: a prospective patient satisfaction survey.

BACKGROUND: Deep brain stimulation (DBS) is highly successful in treating Parkinson's disease (PD), dystonia, and essential tremor (ET). Until recently implantable neurostimulators were nonrechargeable, battery-driven devices, with a lifetime of about 3-5 years. This relatively short duration causes problems for patients (e.g. programming and device-use limitations, unpredictable expiration, surgeries to replace depleted batteries). Additionally, these batteries (relatively large with considerable weight) may cause discomfort. To overcome these issues, the first rechargeable DBS device was introduced: smaller, lighter and intended to function for 9 years. METHODS: Of 35 patients implanted with the rechargeable device, 21 (including 8 PD, 10 dystonia, 2 ET) were followed before and 3 months after surgery and completed a systematic survey of satisfaction with the rechargeable device. RESULTS: Overall patient satisfaction was high (83.3 ± 18.3). Dystonia patients tended to have lower satisfaction values for fit and comfort of the system than PD patients. Age was significantly negatively correlated with satisfaction regarding process of battery recharging. CONCLUSIONS: Dystonia patients (generally high-energy consumption, severe problems at the DBS device end-of-life) are good, reliable candidates for a rechargeable DBS system. In PD, younger patients, without signs of dementia and good technical understanding, might have highest benefit.

The OSCAR-MP Consensus Criteria for Quality Assessment of Retinal Optical Coherence Tomography Angiography.

BACKGROUND AND OBJECTIVES: Optical coherence tomography angiography (OCTA) is a noninvasive high-resolution imaging technique for assessing the retinal vasculature and is increasingly used in various ophthalmologic, neuro-ophthalmologic, and neurologic diseases. To date, there are no validated consensus criteria for quality control (QC) of OCTA. Our study aimed to develop criteria for OCTA quality assessment. METHODS: To establish criteria through (1) extensive literature review on OCTA artifacts and image quality to generate standardized and easy-to-apply OCTA QC criteria, (2) application of OCTA QC criteria to evaluate interrater agreement, (3) identification of reasons for interrater disagreement, revision of OCTA QC criteria, development of OCTA QC scoring guide and training set, and (4) validation of QC criteria in an international, interdisciplinary multicenter study. RESULTS: We identified 7 major aspects that affect OCTA quality: (O) obvious problems, (S) signal strength, (C) centration, (A) algorithm failure, (R) retinal pathology, (M) motion artifacts, and (P) projection artifacts. Seven independent raters applied the OSCAR-MP criteria to a set of 40 OCTA scans from people with MS, Sjogren syndrome, and uveitis and healthy individuals. The interrater kappa was substantial (κ 0.67). Projection artifacts were the main reason for interrater disagreement. Because artifacts can affect only parts of OCTA images, we agreed that prior definition of a specific region of interest (ROI) is crucial for subsequent OCTA quality assessment. To enhance artifact recognition and interrater agreement on reduced image quality, we designed a scoring guide and OCTA training set. Using these educational tools, 23 raters from 14 different centers reached an almost perfect agreement (κ 0.92) for the rejection of poor-quality OCTA images using the OSCAR-MP criteria. DISCUSSION: We propose a 3-step approach for standardized quality control: (1) To define a specific ROI, (2) to assess the occurrence of OCTA artifacts according to the OSCAR-MP criteria, and (3) to evaluate OCTA quality based on the occurrence of different artifacts within the ROI. OSCAR-MP OCTA QC criteria achieved high interrater agreement in an international multicenter study and is a promising QC protocol for application in the context of future clinical trials and studies.

Can observers link dream content to behaviours in rapid eye movement sleep behaviour disorder? A cross-sectional experimental pilot study.

Motor activity in rapid eye movement (REM) sleep behaviour disorder (RBD) has been linked to dream content. Systematic and controlled sleep laboratory studies directly assessing the relation between RBD behaviours and experienced dream content are, however, largely lacking. We aimed to investigate whether a link can be established between RBD behaviours and dream content when both are systematically sampled in a controlled setting. We investigated six patients with Parkinson syndrome and RBD who underwent 2-3 nights of video-polysomnographic recording during which they were awakened from REM sleep (10 min after the onset of the second and successive REM periods). Spontaneous free-worded dream reports and a structured dream questionnaire were obtained. Video recordings of motor manifestations were each combined with four dream reports, and seven judges had to match the video clip with the correctly reported dream content from a choice of four possibilities. Of the 35 REM sleep awakenings performed, a total of 17 (48.6%) motor-behavioural episodes with recalled dream content were obtained. The mean of correctly identified video-dream pairs was 39.5% (range 0-100%). Our data showed that reported dream content can be linked to motor behaviours above chance level. Matching accuracy was affected mainly by the clarity of dream reports and the specific nature of movements manifest in video recordings.

Effect of costunolide and dehydrocostus lactone on cell cycle, apoptosis, and ABC transporter expression in human soft tissue sarcoma cells.

Human soft tissue sarcomas represent a rare group of malignant tumours that frequently exhibit chemotherapeutic resistance and increased metastatic potential following unsuccessful treatment. In this study, we investigated the effects of costunolide and dehydrocostus lactone, which have been isolated from Saussurea lappa using activity-guided isolation, on three soft tissue sarcoma cell lines of various origins. The effects on cell proliferation, cell cycle distribution, apoptosis induction, and ABC transporter expression were analysed. Both compounds inhibited cell viability dose- and time-dependently. IC50 values ranged from 6.2 µg/mL to 9.8 µg/mL. Cells treated with costunolide showed no changes in cell cycle, little in caspase 3/7 activity, and low levels of cleaved caspase-3 after 24 and 48 h. Dehydrocostus lactone caused a significant reduction of cells in the G1 phase and an increase of cells in the S and G2/M phase. Moreover, it led to enhanced caspase 3/7 activity, cleaved caspase-3, and cleaved PARP indicating apoptosis induction. In addition, the influence of costunolide and dehydrocostus lactone on the expression of ATP binding cassette transporters related to multidrug resistance (ABCB1/MDR1, ABCC1/MRP1, and ABCG2/BCRP1) was examined using real-time RT-PCR. The expressions of ABCB1/MDR1 and ABCG2/BCRP1 in liposarcoma and synovial sarcoma cells were significantly downregulated by dehydrocostus lactone. Our data demonstrate for the first time that dehydrocostus lactone affects cell viability, cell cycle distribution and ABC transporter expression in soft tissue sarcoma cell lines. Furthermore, it led to caspase 3/7 activity as well as caspase-3 and PARP cleavage, which are indicators of apoptosis. Therefore, this compound may be a promising lead candidate for the development of therapeutic agents against drug-resistant tumours.

Dynamics of Retinal Vessel Loss After Acute Optic Neuritis in Patients With Relapsing Multiple Sclerosis.

BACKGROUND AND OBJECTIVES: Rarefication of the retinal vasculature as measured by optical coherence tomography angiography (OCT-A) is a novel finding in patients with multiple sclerosis (MS). This study aimed to analyze longitudinal dynamics of the retinal vasculature following an acute inflammatory relapse including acute optic neuritis (ON) and to search for associations with alterations of the retinal architecture and visual function. METHODS: This prospective longitudinal cohort study included patients with relapsing-remitting MS or clinically isolated syndrome having an acute ON (n = 20) or a non-ON relapse (n = 33). Patients underwent examinations at baseline and after 7, 14, 28, 90, and 180 days with OCT, OCT-A, and assessment of the high- (HCVA) and low-contrast visual acuity (LCVA). RESULTS: Retinal vessel loss of the superficial vascular complex (SVC) evolves early after ON and reaches a plateau between 90 and 180 days (relative vessel loss 15% ± 8% [mean ± SD]). In addition, an 18% ± 18% intraindividual increase of the foveal avascular zone (FAZ) is evident within 180 days after acute ON. Both SVC thinning and FAZ enlargement were associated with worse HCVA and LCVA. Rarefication of the SVC evolved simultaneously to thinning of the common ganglion cell and inner plexiform layer (GCIP) after ON. No alterations of the deep vascular complex were seen in eyes with ON, and no alterations of the retinal vasculature were recognized in patients having acute non-ON relapses. DISCUSSION: Rarefication of the SVC and growing of the FAZ evolve rapidly after ON and are linked to persistent visual disability. ON-related SVC thinning might be closely linked to GCIP atrophy and might occur due to an altered local metabolic activity within inner retinal layers.

Supernumerary phantom limb as a rare symptom of epileptic seizures--case report and literature review.

Supernumerary phantom limbs, that is, the awareness of an illusory extra limb is a fascinating neurologic symptom that has been described in a number of neurologic diseases including stroke, spinal injury, and epilepsy. Herein we report a case of a 70-year-old male patient with new-onset focal seizures with left-sided supernumerary phantom arm and leg as the only seizure manifestation. Ictal single-photon emission computed tomography (SPECT) revealed a hyperperfusion in the right temporoparietal junction and allowed localization of the seizure-onset zone. This report is accompanied by a discussion of phenomenology and terminology in the context of existing literature.

Fully human, HLA-DR-specific monoclonal antibodies efficiently induce programmed death of malignant lymphoid cells.

The Human Combinatorial Antibody Library (HuCAL) was screened for antibodies specific to human leukocyte antigen-DR (HLA-DR) that induce programmed death of lymphoma/leukemia cells expressing the target antigen. The active Fab fragments were affinity-matured, and engineered to IgG(4) antibodies of sub-nanomolar affinity. The antibodies exhibited potent in vitro tumoricidal activity on several lymphoma and leukemia cell lines and on chronic lymphocytic leukemia patient samples. They were also active in vivo in xenograft models of non-Hodgkin lymphoma. Cell death occurred rapidly, without the need for exogenous immunological effector mechanisms, and was selective to activated/tumor-transformed cells. Although the expression of HLA-DR on normal hematopoietic cells is a potential safety concern, the antibodies caused no long-lasting hematological toxicity in primates, in vivo. Such monoclonal antibodies offer the potential for a novel therapeutic approach to lymphoid malignancies.

Auto-aggressive metallic mercury injection around the knee joint: a case report.

BACKGROUND: Accidental or intentional subcutaneous and/or intramuscular injection of metallic mercury is an uncommon form of poisoning. Although it does not carry the same risk as mercury vapour inhalation, it may cause destructive early and late reactions. CASE PRESENTATION: Herein we present the case of a 29-year-old male patient who developed an obsessive-compulsive disorder causing auto-aggressive behaviour with injection of elemental mercury and several other foreign bodies into the soft tissues around the left knee about 15 years before initial presentation. For clinical examination X-rays and a CT-scan of the affected area were performed. Furthermore, blood was taken to determine the mercury concentration in the blood, which showed a concentration 17-fold higher than recommended. As a consequence, the mercury depots and several foreign bodies were resected marginally. CONCLUSION: Blood levels of mercury will decrease rapidly following surgery, especially in combination with chelating therapy. In case of subcutaneous and intramuscular injection of metallic mercury we recommend marginal or wide excision of all contaminated tissue to prevent migration of mercury and chronic inflammation. Nevertheless, prolonged clinical and biochemical monitoring should be performed for several years to screen for chronic intoxication.

Hepatic but not brain iron is rapidly chelated by deferasirox in aceruloplasminemia due to a novel gene mutation.

BACKGROUND & AIMS: Aceruloplasminemia is a rare autosomal recessive neurodegenerative disease associated with brain and liver iron accumulation which typically presents with movement disorders, retinal degeneration, and diabetes mellitus. Ceruloplasmin is a multi-copper ferroxidase that is secreted into plasma and facilitates cellular iron export and iron binding to transferrin. RESULTS: A novel homozygous ceruloplasmin gene mutation, c.2554+1G>T, was identified as the cause of aceruloplasminemia in three affected siblings. Two siblings presented with movement disorders and diabetes. Complementary DNA sequencing showed that this mutation causes skipping of exon 14 and deletion of amino acids 809-852 while preserving the open reading frame. Western blotting of liver extracts and sera of affected patients showed retention of the abnormal protein in the liver. Aceruloplasminemia was associated with severe brain and liver iron overload, where hepatic mRNA expression of the iron hormone hepcidin was increased, corresponding to the degree of iron overload. Hepatic iron concentration normalized after 3 and 5months of iron chelation therapy with deferasirox, which was also associated with reduced insulin demands. During short term treatment there was no clinical or imaging evidence for significant effects on brain iron overload. CONCLUSIONS: Aceruloplasminemia can show an incomplete clinical penetrance but is invariably associated with iron accumulation in the liver and in the brain. Iron accumulation in aceruloplasminemia is a result of defective cellular iron export, where hepcidin regulation is appropriate for the degree of iron overload. Iron chelation with deferasirox was effective in mobilizing hepatic iron but has no effect on brain iron.

Long-term antidyskinetic efficacy of amantadine in Parkinson's disease.

Several randomized placebo-controlled trials have consistently shown antidyskinetic effects of amantadine in levodopa treated patients with advanced Parkinson's disease (PD). However, all of these were of short duration and there have been claims that the effect of amantadine on levodopa induced dyskinesias (LID's) wear off after about 9 months of treatment. This randomized placebo-controlled parallel-group study was performed to assess the long-term antidyskinetic effect of amantadine in 32 PD patients, who after having been on stable amantadine therapy for LID over at least one year- were switched in a double blind manner to amantadine or placebo and followed for 3 weeks. Dyskinesia duration and intensity were assessed by UPDRS IV items 32 and 33 as well as by patient's diaries. The primary outcome was the score change of UPDRS IV items 32 + 33 between baseline and 3 weeks after treatment as well as the between treatment group comparison of the score change of UPDRS IV items 32 + 33. There was a significant increase of UPDRS IV items 32 + 33 in patients treated with placebo from 3.06 (95% CI, 2.1-4.03) at baseline to 4.28 (95% CI, 3.1-5.4) at three-week follow-up (P = 0.02) compared with no significant change between baseline 3.2 (95% CI, 2.1-4.4) to follow-up 3.6 (95% CI, 2.3-4.8) in patients staying on amantadine. These findings argue for long-term antidyskinetic efficacy of amantadine in PD patients with LID's.

Has Deep Brain Stimulation Changed the Very Long-Term Outcome of Parkinson's Disease? A Controlled Longitudinal Study.

BACKGROUND: The long-term impact of deep brain stimulation (DBS) on Parkinson's disease (PD) is difficult to assess and has not yet been rigorously evaluated in comparison to its natural history. OBJECTIVE: Comparison of key disability milestones (recurrent falls, psychosis, dementia, and institutionalization) and death in patients with PD with versus without DBS. METHODS: We collected retrospective information from clinical notes of patients with PD at our center that were implanted with subthalamic DBS >8 years ago (1999-2010) and a control group of PD patients without DBS similar in age at onset, age at baseline, sex distribution, and number of comorbidities at baseline (extracted from a registry study performed in 2004). Cox regression models were used to calculate hazard ratios, adjusted for potential baseline confounding variables (age, sex, disease duration, disease severity, and number of comorbidities). RESULTS: A total of 74 DBS-treated and 61 control patients with PD were included. For a median observational period of 14 years, patients treated with DBS were at lower risk of experiencing recurrent falls (hazard ratio = 0.57; 95% confidence interval, 0.37-0.90; P = 0.015) and psychosis (hazard ratio = 0.26; 95% confidence interval, 0.12-0.59; P = 0.001) compared with control patients. There was no significant difference in risk for dementia, institutionalization, or death. Disease progression as assessed by Hoehn and Yahr scores was not slower in DBS-treated patients. CONCLUSIONS: Treatment with chronic subthalamic DBS was associated with lower risk for recurrent falls and psychotic symptoms, effects that may be mediated through improved motor symptom control and reduction in dopaminergic therapies, respectively. There was no evidence for DBS effects on underlying disease progression.

A randomized trial of deep-brain stimulation for Parkinson's disease.

BACKGROUND: Neurostimulation of the subthalamic nucleus reduces levodopa-related motor complications in advanced Parkinson's disease. We compared this treatment plus medication with medical management. METHODS: In this randomized-pairs trial, we enrolled 156 patients with advanced Parkinson's disease and severe motor symptoms. The primary end points were the changes from baseline to six months in the quality of life, as assessed by the Parkinson's Disease Questionnaire (PDQ-39), and the severity of symptoms without medication, according to the Unified Parkinson's Disease Rating Scale, part III (UPDRS-III). RESULTS: Pairwise comparisons showed that neurostimulation, as compared with medication alone, caused greater improvements from baseline to six months in the PDQ-39 (50 of 78 pairs, P=0.02) and the UPDRS-III (55 of 78, P<0.001), with mean improvements of 9.5 and 19.6 points, respectively. Neurostimulation resulted in improvements of 24 to 38 percent in the PDQ-39 subscales for mobility, activities of daily living, emotional well-being, stigma, and bodily discomfort. Serious adverse events were more common with neurostimulation than with medication alone (13 percent vs. 4 percent, P<0.04) and included a fatal intracerebral hemorrhage. The overall frequency of adverse events was higher in the medication group (64 percent vs. 50 percent, P=0.08). CONCLUSIONS: In this six-month study of patients under 75 years of age with severe motor complications of Parkinson's disease, neurostimulation of the subthalamic nucleus was more effective than medical management alone. (ClinicalTrials.gov number, NCT00196911 [ClinicalTrials.gov].).

Restless legs syndrome in Parkinson's disease.

We aimed to investigate the prevalence of restless legs syndrome (RLS) according to essential diagnostic criteria, and to explore potential associations with clinical features, especially motor fluctuations, in a cohort of 113 patients with idiopathic Parkinson's disease (PD). Twenty-eight (24%) fulfilled essential diagnostic criteria for RLS. They were younger (63.1 +/- 8.6 vs. 68.8 +/- 9.0 years; P = 0.004), had an earlier onset of PD (54.1 +/- 9.5 vs. 59.2 +/- 10.3 years; P = 0.018), and received lower levodopa equivalent doses (578.4 +/- 382.2 vs. 779.1 +/- 459.6 mg/day; P = 0.04) than patients with PD who scored negative for RLS. In 23 patients (82%), RLS symptom onset was after PD onset (mean interval, 4.5 +/- 3.7 years). The majority (n = 17, 61%) who scored positive for RLS reported that the urge to move the legs and unpleasant sensations were associated with wearing off, raising the possibility of RLS mimics in fluctuating patients with PD.

In vitro affinity maturation of human GM-CSF antibodies by targeted CDR-diversification.

The mammalian immune system applies somatic hypermutation to select for antibodies with improved dissociation rates in vivo up to an intrinsic limit, previously termed as affinity ceiling. However, for certain therapeutic applications it may be desirable to further improve antibody affinities beyond that limit. In this study the selection of antibodies specific for the pro-inflammatory cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF) from the HuCAL GOLD human antibody library is described. In order to increase affinity and also functional activity, in vitro affinity maturation of a pool of lead Fab candidates was carried out. CDR-L3 and parallel CDR-H2 diversification using trinucleotide consensus cassettes were followed by the combination of optimized CDR-L3 and CDR-H2 leading to a 5000-fold improved affinity finally reaching a K(D) of 400 fM. Cytokine neutralizing potential of MOR04357 was evaluated in a TF-1 proliferation assay. Along with affinity optimization a 2000-fold increase in potency was observed compared to the parental antibody. Due to species cross-reactivity MOR04357 also blocks rat GM-CSF induced proliferation of FDCP-1 cells. Receptor inhibition studies showed that MOR04357 prevents the interaction of GM-CSF with the GM-CSF receptor alpha chain. As a consequence this leads to a blockade in signal transduction as measured by abolished STAT5 phosphorylation in the presence of GM-CSF and antibody. Due to its pro-inflammatory role GM-CSF has been implicated in the pathophysiology of inflammatory diseases like rheumatoid arthritis or asthma. Based on the mode of action described herein MOR04357 shows favourable antibody features as a potential drug candidate.