The 22q13.3 Deletion Syndrome (Phelan-McDermid Syndrome)

The 22q13.3 deletion syndrome, also known as Phelan-McDermid syndrome, is a contiguous gene disorder resulting from deletion of the distal long arm of chromosome 22. In addition to normal growth and a constellation of minor dysmorphic features, this syndrome is characterized by neurological deficits which include global developmental delay, moderate to severe intellectual impairment, absent or severely delayed speech, and neonatal hypotonia. In addition, more than 50% of patients show autism or autistic-like behavior, and therefore it can be classified as a syndromic form of autism spectrum disorders (ASD). The differential diagnosis includes Angelman syndrome, velocardiofacial syndrome, fragile X syndrome, and FG syndrome. Over 600 cases of 22q13.3 deletion syndrome have been documented. Most are terminal deletions of ∼100 kb to >9 Mb, resulting from simple deletions, ring chromosomes, and unbalanced translocations. Almost all of these deletions include the gene SHANK3 which encodes a scaffold protein in the postsynaptic densities of excitatory synapses, connecting membrane-bound receptors to the actin cytoskeleton. Two mouse knockout models and cell culture experiments show that SHANK3 is involved in the structure and function of synapses and support the hypothesis that the majority of 22q13.3 deletion syndrome neurological defects are due to haploinsufficiency of SHANK3, although other genes in the region may also play a role in the syndrome. The molecular connection to ASD suggests that potential future treatments may involve modulation of metabotropic glutamate receptors.

Anti-IgE for chronic asthma in adults and children

BACKGROUND

Omalizumab is a recombinant humanised monoclonal antibody directed against immunoglobulin E (anti-IgE) to inhibit the immune system's response to allergen exposure. Omalizumab is directed against the binding site of IgE for its high affinity Fc receptor. It prevents free serum IgE from attaching to mast cells and other effector cells and prevents IgE mediated inflammatory changes.

OBJECTIVES

To determine the efficacy of anti-IgE compared with placebo in patients with allergic asthma

SEARCH STRATEGY

We searched the Cochrane Airways Group Asthma trials register for potentially relevant studies (February 2006).

SELECTION CRITERIA

Randomised controlled trials examining anti-IgE administered in any manner for any duration. Trials with co-interventions were included as long as they were the same in each arm.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed study quality and extracted and entered data. Three modes of administration were identified from the published literature (inhaled, intravenous and subcutaneous injection). Subgroup analysis was performed by asthma severity. Data were extracted from published and unpublished sources.

MAIN RESULTS

Fourteen trials (15 group comparisons) were included in the review, contributing a total of 3143 mild to severe allergic asthmatic participants with high levels of IgE. Treatment with intravenous and subcutaneous Omalizumab significantly reduced free IgE compared with placebo. Omalizumab led to a significant reduction in inhaled steroid (ICS) consumption compared with placebo (-119 mcg/day (95% CI -154 to -83, three trials)). There were significant increases in the number of participants who were able to reduce ICS by over 50% (odds ratio (OR) 2.50, 95% confidence interval (CI) 2.02 to 3.10 (four trials)); or completely withdraw their daily ICS intake (OR 2.50 (95%CI 2.00 to 3.13; four trials)). Participants treated with Omalizumab were less likely to suffer an asthma exacerbation with treatment as an adjunct to ICS (OR 0.52, 95%CI 0.41 to 0.65, five trials), or as an ICS tapering agent (OR 0.47, 95% CI 0.37 to 0.60, four trials).

AUTHORS' CONCLUSIONS

Omalizumab was significantly more effective than placebo at increasing the numbers of patients who were able to reduce or withdraw their inhaled steroids, but the clinical value of the reduction in steroid consumption has be considered in the light of the high cost of Omalizumab. The impressive placebo effects observed in control groups bring into question the true effect of Omalizumab. Omalizumab was effective in reducing asthma exacerbations as an adjunctive therapy to inhaled steroids, and during steroid tapering phases of clinical trials. Omalizumab was generally well tolerated, although there were more injection site reactions with Omalizumab. Patient and physician assessments of the drug were positive. Further assessment in paediatric populations is necessary, as is direct double-dummy comparison with ICS.

Trends and patterns of playground injuries in United States children and adolescents

OBJECTIVE

To determine the prevalence, trends, and severity of injuries attributable to playground falls relative to other common unintentional mechanisms that resulted in an emergency department (ED) visit in the United States.

DESIGN AND SETTING

Data from the emergency subset of the National Hospital Ambulatory Medical Care Survey collected from 1992 to 1997 for children <20 years.

METHODS

Injury rates and 95% confidence intervals (CIs) were estimated and injury severity scores were computed.

RESULTS

There were 920551 (95% CI: 540803 to 1300299) ED visits over the 6-year study period by children and adolescents that were attributable to falls from playground equipment. The annual incidence of visits for playground injuries did not significantly decrease over the course of the study (187000 to 98000, P =.053). Injury visits for playground falls were twice as prevalent as pedestrian mechanisms, but they were less prevalent than visits for motor vehicle-- and bicycle-related injuries. A larger proportion of playground falls resulted in "moderate-to-severe" injury than did bicycle or motor vehicle injuries. Children aged 5 to 9 years had the highest number of playground falls (P =.0014). Playground falls were most likely to occur at school compared to home, public, and other locations (P =.0016).

CONCLUSIONS

Playground injury emergency visits have not significantly declined and remain a common unintentional mechanism of injury. Injury visits for playground falls were proportionally more severe than injury visits attributable to other common unintentional mechanisms. Interventions targeting schools and 5- to 9-year-old children may have the greatest impact in reducing emergency visits for playground injuries.

Cambridge hybrid closed-loop algorithm in children and adolescents with type 1 diabetes: a multicentre 6-month randomised controlled trial

BACKGROUND

Closed-loop insulin delivery systems have the potential to address suboptimal glucose control in children and adolescents with type 1 diabetes. We compared safety and efficacy of the Cambridge hybrid closed-loop algorithm with usual care over 6 months in this population.

METHODS

In a multicentre, multinational, parallel randomised controlled trial, participants aged 6-18 years using insulin pump therapy were recruited at seven UK and five US paediatric diabetes centres. Key inclusion criteria were diagnosis of type 1 diabetes for at least 12 months, insulin pump therapy for at least 3 months, and screening HbA1c levels between 53 and 86 mmol/mol (7·0-10·0%). Using block randomisation and central randomisation software, we randomly assigned participants to either closed-loop insulin delivery (closed-loop group) or to usual care with insulin pump therapy (control group) for 6 months. Randomisation was stratified at each centre by local baseline HbA1c. The Cambridge closed-loop algorithm running on a smartphone was used with either (1) a modified Medtronic 640G pump, Medtronic Guardian 3 sensor, and Medtronic prototype phone enclosure (FlorenceM configuration), or (2) a Sooil Dana RS pump and Dexcom G6 sensor (CamAPS FX configuration). The primary endpoint was change in HbA1c at 6 months combining data from both configurations. The primary analysis was done in all randomised patients (intention to treat). Trial registration ClinicalTrials.gov, NCT02925299.

FINDINGS

Of 147 people initially screened, 133 participants (mean age 13·0 years [SD 2·8]; 57% female, 43% male) were randomly assigned to either the closed-loop group (n=65) or the control group (n=68). Mean baseline HbA1c was 8·2% (SD 0·7) in the closed-loop group and 8·3% (0·7) in the control group. At 6 months, HbA1c was lower in the closed-loop group than in the control group (between-group difference -3·5 mmol/mol (95% CI -6·5 to -0·5 [-0·32 percentage points, -0·59 to -0·04]; p=0·023). Closed-loop usage was low with FlorenceM due to failing phone enclosures (median 40% [IQR 26-53]), but consistently high with CamAPS FX (93% [88-96]), impacting efficacy. A total of 155 adverse events occurred after randomisation (67 in the closed-loop group, 88 in the control group), including seven severe hypoglycaemia events (four in the closed-loop group, three in the control group), two diabetic ketoacidosis events (both in the closed-loop group), and two non-treatment-related serious adverse events. There were 23 reportable hyperglycaemia events (11 in the closed-loop group, 12 in the control group), which did not meet criteria for diabetic ketoacidosis.

INTERPRETATION

The Cambridge hybrid closed-loop algorithm had an acceptable safety profile, and improved glycaemic control in children and adolescents with type 1 diabetes. To ensure optimal efficacy of the closed-loop system, usage needs to be consistently high, as demonstrated with CamAPS FX.

FUNDING

National Institute of Diabetes and Digestive and Kidney Diseases.

Maternal depression, child behavior, and injury

BACKGROUND

Few data exist on the effect of maternal depression on child injury outcomes and mediators of this relationship.

OBJECTIVE

To examine the relationship between mothers' depressive symptoms and medically attended injuries in their children and the potential mediating role of child behavior.

DESIGN/METHODS

A cohort of mother-child dyads from the National Longitudinal Study of Youth followed from 1992 to 1994. The primary exposure variable was maternal depressive symptoms as measured by the Center for Epidemiologic Studies Depression Scale in 1992. Child behavior was assessed by the Behavior Problems Index externalizing subscale. Logistic regression was used to examine the relationship between depressive symptoms, child behavior, and injury reported in the prior year in 1994.

RESULTS

94 medically attended injuries were reported in the 1106 children (8.5%); two-thirds were sustained in the home environment. Maternal depressive symptoms significantly increased the risk of child injury; injury risk increased 4% for every 1-point increase in depressive symptoms (adjusted OR 1.04, 95% CI 1.01 to 1.08, p=0.02). Increasing maternal depressive symptoms also increased the risk of externalizing behavior problems (adjusted OR 1.06, 95% CI 1.03 to 1.09), but externalizing behavior problems did not significantly mediate the relationship between maternal symptoms and child injury.

CONCLUSIONS

Increasing depressive symptoms in mothers was associated with an increased risk of child injury. Child behavior did not significantly mediate the association between maternal depressive symptoms and child injury in this cohort. Greater recognition, referral, and treatment of depressive symptoms in mothers may have effects on child behavior and injury risk.

The prognostic significance of the skeletal manifestations of acute lymphoblastic leukemia of childhood

The variety and distribution of skeletal pathology in children with acute lymphoblastic leukemia is rarely seen in other disease states. Skeletal radiographic changes associated with and/or suggestive of acute leukemia include diffuse osteopenia, metaphyseal bands, periosteal new bone formation, geographic lytic lesions, sclerosis, mixed sclerosis/lysis, and permeative destruction. This retrospective analysis of 83 children with acute lymphoblastic leukemia suggests that children without radiographic skeletal abnormalities have an "aggressive" form of leukemia. Children with one to four lesions have an "indolent" form of leukemia that is of short duration. Children with five or more lesions have an indolent form of leukemia that is of longer duration. The longer duration of symptoms before diagnosis reduces the survival rate to that of the aggressive form of leukemia. It is therefore imperative that physicians who treat children recognize the orthopaedic/radiographic manifestations of acute leukemia (the most common pediatric malignancy) to facilitate diagnosis, and, thereby, improve survival.

DNA methylation epi-signature is associated with two molecularly and phenotypically distinct clinical subtypes of Phelan-McDermid syndrome

Background

Phelan-McDermid syndrome is characterized by a range of neurodevelopmental phenotypes with incomplete penetrance and variable expressivity. It is caused by a variable size and breakpoint microdeletions in the distal long arm of chromosome 22, referred to as 22q13.3 deletion syndrome, including the SHANK3 gene. Genetic defects in a growing number of neurodevelopmental genes have been shown to cause genome-wide disruptions in epigenomic profiles referred to as epi-signatures in affected individuals.

Results

In this study we assessed genome-wide DNA methylation profiles in a cohort of 22 individuals with Phelan-McDermid syndrome, including 11 individuals with large (2 to 5.8 Mb) 22q13.3 deletions, 10 with small deletions (< 1 Mb) or intragenic variants in SHANK3 and one mosaic case. We describe a novel genome-wide DNA methylation epi-signature in a subset of individuals with Phelan-McDermid syndrome.

Conclusion

We identified the critical region including the BRD1 gene as responsible for the Phelan-McDermid syndrome epi-signature. Metabolomic profiles of individuals with the DNA methylation epi-signature showed significantly different metabolomic profiles indicating evidence of two molecularly and phenotypically distinct clinical subtypes of Phelan-McDermid syndrome.

Pediatric motor vehicle related injuries in the Navajo Nation: the impact of the 1988 child occupant restraint laws

BACKGROUND

Navajo motor vehicle mortality is the highest among the 12 Indian Health Service (IHS) administrative areas. In July 1988, the Navajo Nation enacted a primary enforcement safety belt use and a child restraint law.

OBJECTIVE

Assess the impact of the laws on the rate and severity of pediatric (0-19 years) motor vehicle injury resulting in hospitalizations in the Navajo Nation.

METHODS

Hospitalizations associated with motor vehicle related injury discharges were identified by International Classification of Diseases, 9th revision, CM E codes, 810-825 (.0,.1) from the Navajo IHS hospital discharge database. Age specific rates for the period before the law, 1983-88, were compared with those after enactment and enforcement, 1991-95. Severity of injury, measured by the abbreviated injury scale (AIS) score and new injury severity score (NISS), was determined with ICDMAP-90 software. Wilcoxon rank sum and chi(2) tests were used for analysis.

RESULTS

Discharge rates (SE) for motor vehicle injury (per 100 000) decreased significantly in all age groups: 0-4 years (62 (7) to 28 (4)), 5-11 years (55.3 (6) to 26 (4)), and 15-19 years (139 (14) to 68 (7)); p=0.0001. In children 0-4 years, the median AIS score decreased from 1.5 (1,3) (25th, 75th centile) to 1 (1,2), p=0.06, and the median NISS decreased from 3.5 (1,9) to 2 (1,5), p=0.07. The proportion of children with NISS scores >4 decreased significantly for the 0-4 year age group (p=0.03).

CONCLUSIONS

Concurrent with enactment of the Navajo Nation occupant and child restraint laws there was a reduction in the rate of motor vehicle related hospital discharges for children. Severity of injury declined in very young Navajo children. The effect of enactment and enforcement of this Native American child occupant restraint law may serve as an example of an effective injury control effort directed at Native American children.

Predictive value of tube leukocyte adherence inhibition (LAI) assay for breast, colorectal, stomach and pancreatic cancer

The tube LAI assay measures accurately antitumor immunity in patients with early cancer but fails to detect up to 75% of patients with advanced cancer due to excess circulating organ-specific neoantigen (OSN). Substances such as prostaglandin E2 (PGE2) or aminophylline, which increase intracellular nucleotides in leukocytes of patients with advanced cancer reversed this nonreactivity and greatly increased the sensitivity of the assay without any loss of specificity. Antitumor immunity can now be detected in advanced cancer, and a combination of the two assays gives prognostic potential to the assay: a positive test with PGE2 and negative test without indicates the patient has a large tumor burden. The specificity of the assay for each cancer was high and in most instances was greater than or equal to 95%. The PGE2 stimulated assay retained the high specificity. The sensitivity of the regular tube assay was often low, 33-56% because of the many advanced cancer patients tested, whereas the PGE2 stimulated assay showed almost a two-fold increase in sensitivity, 67-93%. The diagnostic value of the assay was estimated by calculating the predictive value for different prevalences of cancer. It was found that at low prevalences of cancer as found in the general population, the assay had a low diagnostic value since few patients with a positive test would have the cancer tested for. With prevalences of cancer of 5% or greater as might be found in a tertiary care clinical setting, the assay would seem to have diagnostic value since one half or more patients with a positive test would have the cancer tested for. Most false positives, but not all, are found in patients who have lesions that are often considered to increase their risk for cancer: severe dysplasia of the breast, colon adenomas, chronic atrophic gastritis and chronic pancreatitis, suggesting that the assay predicts oncogenesis.

Validation of a HOME Injury Survey

BACKGROUND

There are no validated observational surveys to assess injury hazards in the home environment.

OBJECTIVE

To evaluate the reproducibility and reliability of a survey quantifying home injury hazards for children.

METHODS

A nested cohort of children in the intervention arm of the Home Observations and Measures of the Environment (HOME) Study trial were analysed. The number and density of hazards were quantified by research assistants in the homes of participants at a baseline visit (BHV) for four high-risk rooms (kitchen, main activity room, child's bathroom and child's bedroom) and stairways and later at an intervention planning visit (IPV) for the four high-risk rooms and entire household. Statistical analysis included Pearson correlation, Bland-Altman analysis of agreement, analysis of variance and kappa statistics.

RESULTS

There were 163 households with measurements at BHV and IPV. The number and density of hazards for the four high-risk rooms correlated significantly between BHV and IPV (r = 0.50 and 0.75, respectively). The number and density of hazards for the four high-risk rooms correlated significantly with that for the whole household at the IPV (r = 0.17 and 0.52, respectively). The number of injury hazards was significantly higher in the kitchen than in the other high-risk rooms, whereas density was highest in the child's bathroom. Inter-rater reliability between research assistants, as measured by the kappa statistic, was excellent with a mean of 0.81.

CONCLUSIONS

The HOME Injury Survey was a reliable and replicable tool for quantifying residential injury hazards. The density of injury hazards was a more stable and valid measure than the number of injury hazards.

Modulation of antigen-induced leukocyte adherence inhibition by metabolites of arachidonic acid and intracellular nucleotides

After binding a sensitizing tumor antigen, human leukocytes undergo a series of changes that lead to a loss of their glass-adherent properties; a phenomenon called leukocyte adherence inhibition (LAI). After surgery or when patients have a large tumor burden, their test results become negative. This study shows that in vitro incubation of the leukocytes for 5 min with PGE2 converted to positive the negative test, in an immunologically specific manner. The effect was critically dose-dependent, too little or too much did not alter the result. The same effect was achieved with PGE2, PGI2, aminophylline or other drugs that raise intracellular nucleotides, including dibutyryl cyclic AMP and dibutyryl cyclic GMP. Dibutyryl cyclic AMP stimulated a stronger response and 100 times less was needed than of dibutyryl cyclic GMP. Prostaglandins did not mediate LAI since Indomethacin failed to inhibit a positive test. Nonetheless, arachidonate metabolites were critical for the LAI phenomenon since BPB and mepacrine, inhibitors of phospholipase A2, negated the LAI response. Moreover, ETYA, phenidone and NDGA, inhibitors of the lipoxygenase metabolic pathway, all negated the positive LAI response. The positive response was especially sensitive to nullification by ETYA. Although the last-named drugs inhibit other arachidonate metabolic pathways too, conclusive evidence that the metabolites of the lipoxygenase pathway, and leukotrienes in particular, mediate the LAI response was the fact that FPL 55712, a competitive antagonist of SRS, nullified a positive response at levels as low as 10(-13) M. The results imply that prostaglandins were able to modulate the expression of LAI by affecting intracellular nucleotides, but leukotrienes, it seems, were the metabolites that mediated leukocyte nonadherence after monocytes recognized and bound tumor antigen.

Armed human monocytes challenged with a sensitizing cancer extract release substances pharmacologically similar to leukotrienes

Human peripheral blood monocytes were highly enriched by adherence to plastic, armed with serum from cancer patients, and challenged separately and simultaneously with the sensitizing and unrelated cancer extracts. The response of the monocytes was to release a factor that inhibited leukocyte adherence (LAI) to glass. The macrophage-like cell line U937 released a similar factor when it was armed and challenged with the sensitizing cancer extract. The production of the factor was blocked by 10(-6) M ETYA and 10(-6) M NDGA but not by 10(-6) M indomethacin. Moreover, a competitive inhibitor of leukotriene function, 10(-6) M FPL 55712, blocked the LAI reaction mediated by the factor. Arylsulfatase destroyed its activity while depletion of the monocytes' cellular glutathione pool with CyH or Et2Mal stopped production of the mediator. Pure leukotrienes (C and D) in a dose-response fashion prevented the adherence of leukocytes to glass; the nonadherence of mononuclear cells was equal to that of polymorphonuclear cells. PGE2, if added to the leukocytes immediately before challenge with LTC or LTD, increased 1,000-fold the leukocytes' sensitivity to the leukotrienes. Paradoxically, if leukocytes were washed and exposed to PGE2 15 min after being challenged with leukotrienes, their normal glass-adherence property and the ability to respond again to LTD were restored. FPL 55712 blocked the effect of LTC and LTD from inhibiting the adherence of leukocytes to glass. The present study shows that human monocytes armed with cytophilic anti-tumor antibody, when challenged with the sensitizing cancer extract, release leukotriene(s) as shown by pharmacologic evidence, implying that monocytes may play an important inflammatory role in human cancer.

Anti-IgE for chronic asthma in adults and children

BACKGROUND

Omalizumab is a recombinant humanised monoclonal antibody directed against immunoglobulin E (IgE) to inhibit the immune system's response to allergen exposure. Omalizumab is directed against the binding site of IgE for its high affinity Fc receptor. It prevents free serum IgE from attaching to mast cells and other effector cells and prevents IgE mediated inflammatory changes.

OBJECTIVES

To determine the efficacy of anti-IgE in patients with allergic asthma

SEARCH STRATEGY

We searched the Cochrane Airways Group Asthma trials register (February 2003) for potentially relevant studies.

SELECTION CRITERIA

Randomised controlled trials examining anti-IgE administered in any manner for any duration.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed study quality and extracted and entered data. Three modes of administration were identified from the published literature (inhaled, intravenous and subcutaneous injection). Subgroup analysis was performed by asthma severity. Data were extracted from published and unpublished sources.

MAIN RESULTS

Eight trials were included in the review, contributing a total of 2037 mild to severe allergic asthmatic participants with high levels of IgE. Treatment with intravenous and subcutaneous Omalizumab significantly reduced free IgE compared with placebo. Omalizumab led to a significant reduction in inhaled steroid consumption compared with placebo: -114 mcg/day (95% CI -150 to -78.13, two trials). There were significant increases in the number of participants who were able to reduce steroids by over 50%: odds ratio (OR) 2.50, 95% confidence interval (CI) 2.02 to 3.10 (four trials); or completely withdraw their daily steroid intake: OR 2.50, 95%CI 2.00 to 3.13 (four trials). Participants treated with Omalizumab were less likely to suffer an asthma exacerbation with treatment as an adjunct to steroids (OR 0.49, 95%CI 0.38 to 0.64, four trials), or as a steroid tapering agent (OR 0.47, 95% CI 0.37 to 0.60, four trials).

REVIEWERS' CONCLUSIONS

Omalizumab was significantly more effective than placebo at increasing the numbers of patients who were able to reduce or withdraw their inhaled steroids, but the mean difference in steroid consumption achieved with Omalizumab was of debatable clinical value. The impressive effects observed in control groups bring into question the true effect of Omalizumab. Omalizumab was effective in reducing asthma exacerbations as an adjunctive therapy to inhaled steroids. Omalizumab was well tolerated, although the safety profile requires longer term assessment. Patient and physician assessment of the drug was positive. Further assessment in paediatric and severe adult populations is necessary, as is double-dummy comparison with inhaled corticosteroids.

Anti-IgE for chronic asthma

BACKGROUND

Omalizumab is a recombinant humanised monoclonal antibody directed against immunoglobulin E (IgE) to inhibit the immune system's response to allergen exposure. Omalizumab is directed against the binding site of IgE for its high affinity Fc receptor. It prevents free serum IgE from attaching to mast cells and other effector cells and prevents IgE mediated inflammatory changes. The complexes of Omalizumab and IgE formed as a result of treatment are small and not thought to be able to trigger complement activation or give rise to immune complex mediated pathology.

OBJECTIVES

To determine the efficacy of anti-IgE in patients with allergic asthma.

SEARCH STRATEGY

We searched the Cochrane Airways Group Asthma trials register (February 2003) for potentially relevant studies.

SELECTION CRITERIA

Randomised control trials examining anti-IgE administered in any manner for any duration.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed study quality and extracted and entered data. Three modes of administration were identified from the published literature (inhaled, intravenous and subcutaneous injection). Subgroup analysis was performed by asthma severity. Data were extracted from published and unpublished sources.

MAIN RESULTS

Eight trials were included in the review, contributing a total of 2037 mild to severe allergic asthmatic participants with high levels of IgE. Treatment with intravenous and subcutaneous Omalizumab resulted in a 98 to 99% reduction in free IgE, reductions which were not observed following placebo treatment. Significant increases in the number of participants who were able to reduce (> 50% reduction in daily corticosteroid usage (four trials): odds ratio (OR) 2.50, 95% confidence interval (CI) 2.02 to 3.10; or completely withdraw their daily steroid intake (four trials): OR 2.50, 95%CI 2.00 to 3.13, were observed. Participants treated with Omalizumab were less likely to suffer an asthma exacerbation (stable steroid phase (three trials): OR 0.46, 95%CI 0.35 to 0.61; steroid reduction phase (three trials) OR 0.46, 95% CI 0.36 to 0.59).

REVIEWER'S CONCLUSIONS

Omalizumab was significantly more effective than placebo at increasing the numbers of patients who were able to reduce or withdraw their inhaled steroids and was effective in reducing asthma exacerbations. Omalizumab was well tolerated, although the safety profile requires longer term assessment. Patient and physician assessment of the drug was positive. Further assessment in paediatric and severe adult populations is necessary, as is comparison with inhaled corticosteroids.

Oxidative metabolism, cytoskeletal system, and calcium entry of leukocytes in the phenomenon of sensitizing cancer extract-induced leukocyte adherence inhibition

We examined some of the metabolic events that regulate sensitizing cancer extract-induced leukocyte adherence inhibition and found that human leukocytes adhere in a comparatively passive manner to glass in serum-free medium. Adherence of leukocytes to glass did not require oxidative metabolism, microtubules, microfilaments, or calcium entry, whereas leukocyte mobility excited by sensitizing cancer extract did. Calcium antagonists, lanthanum chloride, cromolyn sodium, nifedipine, trifluoperazine, and lidocaine, prevented sensitizing cancer extract-induced leukocyte mobility. Calcium agonist, ionophore A23187, excited leukocyte mobility. Ouabain, which inhibits Na+-K+-adenosine triphosphatase and may increase intracellular Ca2+ as a result, also excited leukocyte mobility. Monocytes, armed with serum from patients with early cancer and challenged with the same sensitizing tumor antigen, generated a leukotriene mediator that excited leukocyte mobility; cromolyn sodium, nifedipine, and trifluoperazine antagonized the synthesis of the mediator. The calcium antagonists inhibited the leukotriene mediator and authentic leukotrienes B4, C4, and D4 from exciting leukocyte mobility. The results showed that leukocyte mobility, excited by sensitizing cancer extract, is an active process depending upon immunologically triggered release of a leukotriené mediator from armed monocytes. Leukocyte adherence inhibition requires many of the same physiological events that chemokinesis and chemotaxis do and is thus an assay to study either immunologically released chemoattractants or chemoattractants themselves on leukocyte locomotion.

Leukocyte adherence inhibition to myelin basic protein by cancer patients' T-lymphocytes in association with class II major histocompatibility antigens on monocytes

Patients' leukocytes were shown to react consistently in tube leukocyte adherence inhibition (LAI) assays with myelin basic protein (MBP) at optimal concentration, whereas control leukocytes were nonreactive. Mononuclear cells from patients with cancer gave positive LAI reactions with MBP, but separated T-lymphocytes, monocytes, and neutrophils did not. The mononuclear cell LAI responses were blocked by monoclonal antibody (MAb) to monomorphic determinant of class II major histocompatibility complex (MHC) antigens and to T4+ (Leu-3a+) and T3+ (Leu-4+) T-cell differentiation antigens but not by antibody to class I MHC antigens or T8+ (Leu-2a+) antigens. MBP was thus recognized by helper T-cells, requiring presentation in association with class II MHC determinants on monocytes. MAb to class I and class II MHC antigens and to T8+ (Leu-2a+), T4+ (Leu-3a+), and T3+ (Leu-4+) differentiation antigens did not negate LAI mediated by peripheral blood lymphocytes to organ-specific cancer neoantigens (OSN) of crude extracts of allogeneic cancer, which had previously been shown to react with cytophilic antibody on allogeneic monocytes. When membrane OSN and leukocytes were autologous, T8+ (Leu-2a+) phenotypic T-cells also mediated LAI that was blocked by anti-T8 (Leu-2a) and anti-T3 (Leu-4). LAI induced by MBP was also negated by drugs that antagonize thromboxane-leukotriene biosynthesis, indicating that, in common with other LAI reactions, the terminal mediators of nonadherence are oxidative metabolites of arachidonic acid. In addition to clarifying the role of MBP in the cellular in vitro immunoreactivity of cancer patients, the present observations have important implications for theories of LAI. Sensitized leukocytes have different mechanisms for the recognition of antigens in different forms, and the antigen-stimulated leukocytes produce mediators that in a final common pathway induce nonadherence of surrounding cells through leukotriene-like metabolites.