Human interleukin-2 receptor beta mutations associated with defects in immunity and peripheral tolerance

Interleukin-2, which conveys essential signals for effective immunity and immunological tolerance, operates through a heterotrimeric receptor. Genetic deficiency of the alpha or gamma chain causes debilitating disease. Here we identify human interleukin-2 receptor (IL-2R) beta chain (IL2RB) gene defects as a cause of life-threatening immune dysregulation. We report three homozygous mutations in the human IL2RB gene of eight individuals from four consanguineous families that cause disease by distinct mechanisms. Nearly all patients presented with autoantibodies, hypergammaglobulinemia, bowel inflammation, dermatological abnormalities, and cytomegalovirus disease. Patient T lymphocytes lacked surface expression of IL-2Rbeta and were unable to respond normally to high-dose IL-2 stimulation. By contrast, patient natural killer (NK) cells retained partial IL-2Rbeta expression and cytotoxic function. IL-2Rbeta loss of function was recapitulated in a recombinant system, in which endoplasmic reticulum sequestration was revealed as the mechanism by which certain missense mutations cause disease. Hematopoietic stem cell transplant resulted in resolution of clinical symptoms in one patient. The hypomorphic nature of this disease highlights the significance of variable IL-2Rbeta expression between different lymphocyte subsets and during their maturation as a means of modulating immune function. Insights from these patients can inform the development of IL-2-based therapeutics for immunological diseases and cancer.

Impact of a novel nutritional formula on asthma control and biomarkers of allergic airway inflammation in children

BACKGROUND

A novel nutritional formula (NNF) enriched in eicosapentaenoic (EPA) and gamma-linolenic fatty acids and antioxidants reduces airway inflammation and improves clinical outcomes in critically ill patients, but NNF has not been evaluated in chronic inflammatory diseases such as persistent asthma.

OBJECTIVE

To evaluate the efficacy, compliance, and safety of NNF in asthmatic children.

METHODS

Children, 6-14 years of age, with mild to moderate persistent asthma, on as needed albuterol alone, were randomized to receive daily NNF (n=23) or control formula (n=20) for 12 weeks, with multiple assessments of asthma control, spirometry, measures of airway inflammation, formula tolerance, and adverse events.

RESULTS

Daily consumption of either NNF or a control formula showed improvement in asthma-free days over time (P=0.04) but there was no difference between groups. However, the NNF group had lower exhaled nitric oxide levels compared with the control group at weeks 4, 8, and 12 (P<0.05). An overall group difference in log FEV1 PC20 (P=0.05) was found in favour of the NNF group as well. Significantly higher levels of EPA in plasma (P<0.01) and peripheral blood mononuclear cell (PBMC) (P<0.01) phospholipids in the NNF group compared with control group within 2 weeks indicated good adherence with daily NNF intake. There were no differences in adverse events for NNF vs. control after 12 weeks.

CONCLUSIONS

Both NNF and control groups demonstrated improvement in asthma-free days. NNF-treated group had reduced biomarkers of disease activity. Rapid PBMC fatty acid composition changes reflected an anti-inflammatory profile. Dietary supplementation with NNF was safe and well tolerated (ClinicalTrials.gov number NCT01087710).

Humanized anti-CEACAM6 PEGylated scFv: A promising novel therapy for pancreatic cancer

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Background: Novel Therapies for pancreatic cancer (PC) based on biological insight are urgently needed. CEACAM6, a member of the carcinoembryonic antigen (CEA) family, is a cell surface oncogene on PC cells. It is a glycoprotein composed of 3 Ig-like domains (Mr ∼35.2kD) and is linked to the plasma membrane via a glycophospholipid linked anchor. It is over-expressed on ≥95% PC patients’ found irrespective of stage of disease and represents a target for antibody therapy. Methods: Murine anti-CEACAM6 monoclonal antibody (Mab) 13–1 was humanized by a structure-based approach and single chain variable fragments (scFv) designed consisting of a Gly/Ser-linker which includes a cysteine residue for PEGylation. Murine scFv and 4 humanized scFv fragments (Version.1, 2, 7, 8) were bacterially expressed, purified, PEGylated and evaluated for activity alone or in combination with gemcitabine in human PC cell lines and mouse xenograft tumors. Cell viability, apoptosis and in-cell Westerns were done for efficacy and binding. Mouse xenograft tumors were treated with scFv or PEGylated scFv or combination with gemcitabine. Tumors (treated Vs untreated) were analyzed by immunohistochemistry for Ki-67, CD31, CEACAM6 and Caspase 3 Results: Mab 13–1, murine and 4 humanized scFvs’ were cytotoxic to CEACAM6 expressing PC cells (BxPC-3, HPAF-2) and not to PC cells that lack CEACAM6 (CaPan-2) with increased PARP-cleavage that was dose dependent (IC50=10μg/mL). Western blotting of culture media and serum from xenograft mice showed that CEACAM6 is not shed. In-cell Western confirmed humanized V.7 to be the best binder (KD=1–10μg/mL) confirming protein-protein interaction studies performed in silico with homology models of murine and humanized scFvs’ and CEACAM6. The murine scFv alone or the humanized scFV (V.8) in combination with gemcitabine delayed tumor growth by >50%. This tumor reduction correlated well with the immunohistochemical markers of response. Conclusions: We have demonstrated that CEACAM6 is a clinically relevant target in PC and that a PEGylated humanized scFv is a novel effective therapy alone and/or in combination with gemcitabine. Humanized scFv V.7 is undergoing mouse xenograft evaluation and expect will be the most effective agent to take forward into clinical development.

No significant financial relationships to disclose.

rFVIIa--for acute rebleeding of a cerebral cavernous malformation

Recurrent bleeding episodes of cavernomas especially in the brainstem can cause progressive neurological deficits. Therefore brainstem cavernomas are still a therapeutic dilemma and a treatment challenge for the neuro critical care community. We report a 39-year-old woman with spontaneous ataxia diplopia and vomiting, who has been treated for multiple intracerebral cavernomas during the last 10 years. A cerebral computed tomography (cCT) revealed a re-bleeding cavernoma in the left cerebral peduncle with consecutive obstructive hydrocephalus. As a result of the difficult anatomical location, no surgical approach was possible. As an off-label treatment, recombinant activated factor VII (rFVIIa) was administered to prevent possible further bleeding and especially further sequelae. The patient recovered well and no adverse events and especially no further bleeding of the cavernoma were observed. To our knowledge, this is the first report of the safe and successful use of rFVIIa to treat re-bleeding episodes in cavernomas. Further clinical studies are needed to specify the future potential of rFVIIa.

Unusual Manifestation of Acute Hepatic Porphyria in Pregnancy

A 22-year-old para I/gravida II developed psychiatric symptoms at 8 weeks of gestation. Subsequently neurological symptoms with seizures developed leading to a status epilepticus with continuing seizures at week 14. Anticonvulsive therapy had little effect in alleviating the seizures and the condition of the patient rapidly deteriorated. A sudden reddening of her urine lead to the diagnosis of acute hepatic porphyria confirmed by laboratory tests. After extensive discussion with the patient's family it was decided to terminate the pregnancy at week 16. Within hours after pregnancy termination the seizures stopped and the patient recovered without any neurological deficits. Acute hepatic porphyria can be triggered by pregnancy and usually presents with gastrointestinal symptoms and personality changes. In its rare neurological manifestation it can lead to untreatable convulsions which leave no option but to terminate the pregnancy.

Menstrual cycle dependent right-to-left shunting: a single-blinded transcranial Doppler sonography study

BACKGROUND AND PURPOSE

Menstruation has been described as risk factor for neurological decompression sickness in divers. In considering this for paradoxical gas embolism, we hypothesized that there may be a link between cycle-dependent hormonal changes and the manifestation of a right-to-left shunt (RLS).

METHODS

40 women with a regular cycle of 28 days underwent transcranial Doppler sonography examinations (TCD) on day 1 and on day 15 of the menstrual cycle. Cerebral high intensity transient signs (HITS) proved a RLS.

RESULTS

We found a 25% RLS incidence consistent with the literature. In 7 of 10 shunt-positive women it was detected mainly or exclusively on day 15. This difference in PFO detection rate is statistically significant (p = 0.031), indicating more RLS during the peri-ovulatory period.

CONCLUSIONS

Our results do not support menstruation as a risk factor for neurological decompression sickness. The peri-ovulatory estrogen peak, which leads to systemic vasodilation, may explain our data. Factors that increase the risk for developing a RLS and thereby paradoxical embolism should be avoided, perhaps including diving during the peri-ovulatory period of the menstrual cycle. Furthermore, contrast PFO testing in fertile females may be most sensitive if conducted mid-cycle.

Long-term outcome of radiological-guided insertion of implanted central venous access port devices (CVAPD) for the delivery of chemotherapy in cancer patients: institutional experience and review of the literature

Central venous access port devices (CVAPD) are necessary for delivery of prolonged infusional chemotherapy or in patients with poor peripheral venous access. Previous studies of Hickman catheters report complication rates in about 45% of patients. Our aim was to assess the early and late complication rate, and duration that the CVAPD remained functional, following insertion by interventional radiologists in patients with solid tumours. A prospective study was undertaken in 110 consecutive patients who had insertion of 111 subclavian CVAPD. The median age of patients was 57 years (range 17–83), 64 were females; 68 patients (61%) had gastrointestinal tumours and 25 (23%) had breast cancer. CVAPD were successfully implanted in all but one patient. There were four (4%) immediate major complications: thrombosis 2 and pneumothorax 2. Nine patients (8%) had bruising or pain. Four devices (4%) became infected. In total, 100 CVAPD (90%) were either removed as planned at the end of treatment (n=23) after a median 203 days, or remained in situ for a median of 237 days (7–1133). Premature removal occurred in eight patients due to infection (n=4), thrombosis (n=3) or faulty device (n=1). Four patients were lost to follow-up. Radiological insertion of CVAPD is safe and convenient with low rates of complications.

Refractory status epilepticus due to acute hepatic porphyria in a pregnant woman: induced abortion as the sole therapeutic option?

A 22-years old, 55 kg female patient in the twelfth week of pregnancy developed neuropsychiatric syndromes and in the following status epilepticus. Raised porphyrines and porphyrine precursors were found in the patient's urine. Despite intravenous glucose infusions and appropriate medication no reduction in seizure-frequency and neuropsychiatric syndromes was observed. An abortion was induced. After the interruption and starting of haem arginate therapy, seizure activity stopped and porphyrine precursors returned to normal levels, and after 6 weeks the patient was discharged in excellent clinical condition. This report describes a status epilepticus caused by acute hepatic porphyria, triggered by pregnancy, in a 22-years old woman. To our knowledge this is the first report of induced abortion as successful treatment in acute hepatic porphyria induced status epilepticus.

Cell index--a new parameter for the early diagnosis of ventriculostomy (external ventricular drainage)-related ventriculitis in patients with intraventricular hemorrhage?

Temporary intraventricular catheters for managing acute obstructive hydrocephalus caused by intraventricular haemorrhage carry a high risk of developing ventriculostomy-related ventriculitis (VRV). The aim of this prospective study was to validate a new parameter for the early detection of an intraventricular infection.

METHODS

Patients with external ventricular drainage due to intraventricular haemorrhage were enrolled in this prospective study. Leucocytes and erythrocytes in cerebrospinal fluid (CSF) and peripheral blood as well as bacteriological and chemical analysis of both were examined daily. The ratio of leucocytes to erythrocytes in CSF and leucocytes to erythrocytes in peripheral blood was calculated (so called cell index (CI)) and these values were compared with the "conventionally diagnosed" drain-associated ventriculitis. Furthermore, the CI values of the non-ventriculitis and ventriculitis group were compared using the t-test with adjustment for unequal variances (Welch test).

RESULTS

Thirteen patients with an external ventricular drainage (EVD) expected to be in place for more than seven days were enrolled. Seven patients developed a bacteriologically proven VRV (time 0) within 12 days (mean 8.57). Diagnosis of VRV by CI was possible up to 3 days (mean 2.28) prior to conventional diagnosis. P values (Welch test) showed a significant difference on days -3 (P = 0.03), -2 (P = 0.03) and -1 (P = 0.012) - i.e. 3, 2 or 1 day, respectively, prior to the time point when the CSF culture grew staphylococci -, when compared with the mean cell indices of the controls, and a highly significant difference on time 0 (P < 0.001).

CONCLUSION

The calculated CI allows the diagnosis of nosocomial VRV in patients with intraventricular haemorrhage at a very early point of time.

Amyloid beta 1-42 and tau in cerebrospinal fluid after severe traumatic brain injury

OBJECTIVE

To determine whether CSF amyloid beta 1-42 (Abeta-42) and tau have predictive value for prognosis after head injury.

METHODS

CSF samples were collected from 29 patients with severe head trauma between 1 and 284 days post-trauma. Abeta-42 and tau levels were measured using sandwich ELISA techniques and compared with CSF levels in patients with cognitive disorders and headache.

RESULTS

At all time points, concentrations of Abeta-42 were significantly lower in patients with traumatic brain injury (TBI) than in control groups. A significant correlation existed for Abeta-42 levels and outcome of patients. Below a cutoff of 230 pg/mL, the sensitivity of Abeta-42 to discriminate between good outcome (Glasgow Outcome Score 4 and 5) and poor outcome (Glasgow Outcome Score 1 through 3) was 100% at a specificity of 82%. CSF tau levels were significantly higher in patients with TBI than in any control group. In patients with multiple CSF samples collected at various time points between 1 and 32 days after the trauma, tau levels increased early after TBI, peaked in the second week post-trauma, and slowly decreased thereafter. Independent of outcome, all patients had normal tau levels when CSF was collected more than 43 days post-trauma.

CONCLUSIONS

Abeta-42 and tau may play a potential role in the pathophysiology of TBI. Furthermore, the results of this study suggest that Abeta-42 may be a supportive early predictor for recovery after severe head injury.

Linear scleroderma "en coup de sabre" coexisting with plaque-morphea: neuroradiological manifestation and response to corticosteroids

A 24 year old woman in the 33rd week of pregnancy developed progressive neurological complications with right sided hemiparesis in association with the occurrence of linear scleroderma "en coup de sabre" (LSCS) and pre-existing plaque-morphea, already being treated by balneophototherapy. Further progression of neurological symptoms led to a caesarean section with the delivery of a healthy child. Brain magnetic resonance imaging (MRI) showed focal T2 signal increases in the left frontoparietal region directly adjacent to the area of LSCS. Cerebrospinal fluid analysis revealed oligoclonal bands, suggesting an intracerebral inflammatory process. Subsequent pulsed corticosteroid treatment led to a remission of neurological symptoms and to a marked resolution of the MRI lesions.

Cerebral vasospasm and ischaemic infarction in clipped and coiled intracranial aneurysm patients

The influence of the treatment modalities (clipping/coiling) on the incidence of vasospasm and ischaemic infarction in aneurysm patients is still judged controversially. The purpose of this study was to analyse and compare retrospectively cerebral vasospasm and ischaemic infarction, as well as neurological deficits and outcome within a large population of clipped and coiled patients with ruptured and unruptured aneurysms. Within a 2-year period, a total of 144 interventions (53 clipping/91 coiling) entered the study. Daily bilateral transcranial Doppler sonographic monitoring was performed to observe vasospasm development. All cerebral computed tomography (cCT) and magnetic resonance imaging (MRI) scans were reviewed with respect to occurrence and localization of ischaemic infarctions. Focal neurological deficits were recorded and clinical outcome was evaluated using the Glasgow Outcome Scale. Statistical analysis included the use of multivariate logistic regression models to find determinants of vasospasm, ischaemic infarction and neurological deficits. Altogether, vasospasm was detected after 77 (53.5%) interventions, 61.8% in females (P < 0.01). Clipped patients significantly more often exhibited vasospasms (69.8 vs. 44.0%, P < 0.005) and were treated 1 week longer at the intensive care unit (P < 0.005). Seventy-seven patients (53.5%) developed ischaemic infarctions, 62.3% after clipping and 48.4% after coiling (P > 0.05). In the multivariate analysis, aneurysm-rupture was the strongest predictor for vasospasm and vasospasm was the strongest predictor for infarction. Neurological deficits at discharge (46.5%) were independent of treatment modality, the same applied for the mean Glasgow Outcome Scores. There was no significant difference in mortality between surgical and endovascular treatment (9.4 vs. 12.1%). Whilst the vasospasm incidence was significantly higher after surgical treatment, ischaemic infarctions were only slightly more frequent. The incidence of neurological deficits and clinical outcome was similar in both treatment groups.

Post-infectious central and peripheral nervous system diseases complicating Mycoplasma pneumoniae infection. Report of three cases and review of the literature

Three patients with a central and peripheral nervous system disease complicating a Mycoplasma pneumoniae (M. pn.) infection are presented. Patient 1 suffered from bilateral optic neuritis as well as acute Guillain-Barré syndrome recovering after plasmapheresis. The two other patients suffered from severe haemorrhagic leukoencephalitis (Hurst) which only could be contained by aggressive decompressive craniectomy with duraplasty. All three illnesses were clearly shown to be associated with M. pn. infection. Our three patients represent the full scale of central nervous (CNS) (cerebral and myelitic) as well as peripheral nervous system (PNS) (GBS, optic neuritis) manifestation of a disease caused by the same pathogenetic - post-infectious - mechanism; pathogenic CNS and PNS epitopes might be shared in post-infectious neurological disease following M. pn. infection.