Immunoproteasome assembly: cooperative incorporation of interferon gamma (IFN-gamma)-inducible subunits

LMP2, LMP7, and MECL are interferon gamma-inducible catalytic subunits of vertebrate 20S proteasomes, which can replace constitutive catalytic subunits (delta, X, and Z, respectively) during proteasome biogenesis. We demonstrate that MECL requires LMP2 for efficient incorporation into preproteasomes, and preproteasomes containing LMP2 and MECL require LMP7 for efficient maturation. The latter effect depends on the presequence of LMP7, but not on LMP7 catalytic activity. This cooperative mechanism favors the assembly of homogeneous "immunoproteasomes" containing all three inducible subunits, suggesting that these subunits act in concert to enhance proteasomal generation of major histocompatibility complex class I-binding peptides.

Crystal structure of the von Willebrand Factor A1 domain and implications for the binding of platelet glycoprotein Ib

von Willebrand Factor (vWF) is a multimeric protein that mediates platelet adhesion to exposed subendothelium at sites of vascular injury under conditions of high flow/shear. The A1 domain of vWF (vWF-A1) forms the principal binding site for platelet glycoprotein Ib (GpIb), an interaction that is tightly regulated. We report here the crystal structure of the vWF-A1 domain at 2.3-A resolution. As expected, the overall fold is similar to that of the vWF-A3 and integrin I domains. However, the structure also contains N- and C-terminal arms that wrap across the lower surface of the domain. Unlike the integrin I domains, vWF-A1 does not contain a metal ion-dependent adhesion site motif. Analysis of the available mutagenesis data suggests that the activator botrocetin binds to the right-hand face of the domain containing helices alpha5 and alpha6. Possible binding sites for GpIb are the front and upper surfaces of the domain. Natural mutations that lead to constitutive GpIb binding (von Willebrand type IIb disease) cluster in a different site, at the interface between the lower surface and the terminal arms, suggesting that they disrupt a regulatory region rather than forming part of the primary GpIb binding site. A possible pathway for propagating structural changes from the regulatory region to the ligand-binding surface is discussed.

Epithelial-mesenchymal transition (EMT) signature is inversely associated with T-cell infiltration in non-small cell lung cancer (NSCLC)

Epithelial-mesenchymal transition (EMT) is able to drive metastasis during progression of multiple cancer types, including non-small cell lung cancer (NSCLC). As resistance to immunotherapy has been associated with EMT and immune exclusion in melanoma, it is important to understand alterations to T-cell infiltration and the tumor microenvironment during EMT in lung adenocarcinoma and squamous cell carcinoma. We conducted an integrated analysis of the immune landscape in NSCLCs through EMT scores derived from a previously established 16 gene signature of canonical EMT markers. EMT was associated with exclusion of immune cells critical in the immune response to cancer, with significantly lower infiltration of CD4 T-cells in lung adenocarcinoma and CD4/CD8 T-cells in squamous cell carcinoma. EMT was also associated with increased expression of multiple immunosuppressive cytokines, including IL-10 and TGF-β. Furthermore, overexpression of targetable immune checkpoints, such as CTLA-4 and TIM-3 were associated with EMT in both NSCLCs. An association may exist between immune exclusion and EMT in NSCLC. Further investigation is merited as its mechanism is not completely understood and a better understanding of this association could lead to the development of biomarkers that could accurately predict response to immunotherapy.

Proposal of diagnostic criteria for human cysticercosis and neurocysticercosis

Taenia solium cysticercosis is a major public health problem in several areas of the world. While the disease has a recognized etiologic agent, its definitive histological diagnosis is not possible in most cases because this parasite tends to lodge in cerebral tissues where routine biopsy is not feasible. Therefore, the diagnosis of human cysticercosis (and neurocysticercosis) should rest on the proper interpretation of the patients' symptoms together with data provided by radiological studies and immunologic tests for the detection of anticysticercal antibodies. Unfortunately, the pleomorphism of this parasitic disease creates confusion when non-specific clinical, radiological, or immunologic criteria alone are used to detect cases among populations or to diagnose hospitalized patients with neurological manifestations. We propose a chart of diagnostic criteria for human cysticercosis that objectively permit clinicians and health care workers to evaluate clinical, radiological, immunologic, and epidemiologic data of patients. The chart uses four degrees of criteria: absolute, major, minor, and epidemiologic, that were selected on the basis of their individual diagnostic strength. Interpretation of such criteria will result in three categories of diagnostic certainty: definitive, probable and possible, according to the likelihood that cysticercosis is present in a given person.

A sonographic enthesitic index of lower limbs is a valuable tool in the assessment of ankylosing spondylitis

BACKGROUND

Enthesitis is a remarkable feature of ankylosing spondylitis (AS) not specifically approached by the available measuring tools for the disease. Ultrasonography (US) has proved to be an excellent technique for the assessment of tendon pathology.

OBJECTIVE

To test a Sonographic Entheseal Index (SEI) of the lower limbs in a cohort of patients with AS, as a potential measuring tool.

METHODS

44 patients with AS and 10 healthy controls were enrolled. Bath Ankylosing Spondylitis Functional Index and Bath Ankylosing Spondylitis Disease Activity Index, pain at entheseal points, severity of symptoms, acute-phase reactants, Schober's test and stage of sacroiliitis were recorded. Patients underwent US examination of five entheseal regions from both lower limbs by two experts. Hypoechogenicity, increased tendon thickness, peritendinous oedema and bursitis were considered signs of active inflammation. Insertional bone erosions, intratendinous calcifications, decreased thickness and tears were considered signs of chronic injury. Each alteration independently scored one point. Data were analysed with Spearman's correlation method.

RESULTS

A significant interobserver correlation in SEI scores (p<0.001) and a fine discriminative power between controls and patients were observed. Acute entheseal lesions predominated (63% vs 37%), the most frequent alteration being tendon hypoechogenicity (43%). 72% of all lesions were located at the foot. The SEI correlated with reduction of Schober's test (p<0.02), but not with other activity or severity parameters.

CONCLUSIONS

A scoring method such as the SEI may be of help in characterising entheseal injury in AS, and for decision making in these patients.

Clinical features, diagnostic challenges, and management strategies in checkpoint inhibitor-related pneumonitis

Immune checkpoint inhibitors, including cytotoxic T-lymphocyte antigen 4 (CTLA-4) and programmed cell death-1 (PD-1) inhibitors, represent an effective treatment modality for multiple malignancies. Despite the exciting clinical benefits, checkpoint inhibition is associated with a series of immune-related adverse events (irAEs), many of which can be life-threatening and result in significant treatment delays. Pneumonitis is an adverse event of special interest as it led to treatment-related deaths in early clinical trials. This review summarizes the incidence of pneumonitis during treatment with the different checkpoint inhibitors and discusses the prognostic significance of tumor type. The wide range of clinical, radiographic, and histologic characteristics of checkpoint inhibitor-related pneumonitis is reviewed and followed by guidance on the different management strategies.

Genome-wide association study of type 2 diabetes in a sample from Mexico City and a meta-analysis of a Mexican-American sample from Starr County, Texas

AIMS/HYPOTHESIS

We report a genome-wide association study of type 2 diabetes in an admixed sample from Mexico City and describe the results of a meta-analysis of this study and another genome-wide scan in a Mexican-American sample from Starr County, TX, USA. The top signals observed in this meta-analysis were followed up in the Diabetes Genetics Replication and Meta-analysis Consortium (DIAGRAM) and DIAGRAM+ datasets.

METHODS

We analysed 967 cases and 343 normoglycaemic controls. The samples were genotyped with the Affymetrix Genome-wide Human SNP array 5.0. Associations of genotyped and imputed markers with type 2 diabetes were tested using a missing data likelihood score test. A fixed-effects meta-analysis including 1,804 cases and 780 normoglycaemic controls was carried out by weighting the effect estimates by their inverse variances.

RESULTS

In the meta-analysis of the two Hispanic studies, markers showing suggestive associations (p < 10(-5)) were identified in two known diabetes genes, HNF1A and KCNQ1, as well as in several additional regions. Meta-analysis of the two Hispanic studies and the recent DIAGRAM+ dataset identified genome-wide significant signals (p < 5 × 10(-8)) within or near the genes HNF1A and CDKN2A/CDKN2B, as well as suggestive associations in three additional regions, IGF2BP2, KCNQ1 and the previously unreported C14orf70.

CONCLUSIONS/INTERPRETATION

We observed numerous regions with suggestive associations with type 2 diabetes. Some of these signals correspond to regions described in previous studies. However, many of these regions could not be replicated in the DIAGRAM datasets. It is critical to carry out additional studies in Hispanic and American Indian populations, which have a high prevalence of type 2 diabetes.

Intramedullary spinal cord metastasis: report of three cases and review of the literature

BACKGROUND

Intramedullary spinal cord metastasis is rare; but it is being encountered with increasing frequency. Optimal treatment after diagnosis remains controversial.

METHODS

In the last 3 years, we have encountered three cases of intramedullary metastasis presenting as focal mass lesions with minimal systemic evidence of cancer. We present our results in these patients and review the literature in an effort to more optimally define both the natural course of this disease, as well as a potential subset of patients who might benefit from more aggressive treatment.

RESULTS

With the availability of more sensitive imaging techniques, these tumors are being diagnosed with increasing frequency. Magnetic resonance imaging is sensitive, but nonspecific, in distinguishing intramedullary spinal cord metastases from primary cord tumors. Urgent biopsy is often necessary prior to definitive treatment. Radiation with chemotherapy significantly prolongs survival. Radical subtotal resection may offer additional quality survival, especially in cases of metastatic melanoma with an occult primary.

CONCLUSIONS

Regardless of treatment, many patients survive less than 1 year. Intramedullary spinal cord metastasis is a devastating condition, but with appropriate diagnosis and aggressive treatment, selected patients may have substantially increased survival.

Early experience with the Incisionless Operating Platform™ (IOP) for the treatment of obesity : the Primary Obesity Surgery Endolumenal (POSE) procedure

BACKGROUND

We report our initial experience and 6-month outcomes in a single center using the per-oral Incisionless Operating Platform™ (IOP) (USGI Medical) to place transmural plications in the gastric fundus and distal body using specialized suture anchors (the Primary Obesity Surgery Endolumenal [POSE] procedure).

METHODS

A prospective observational study was undertaken with institutional Ethics Board approval in a private hospital in Barcelona, Spain. Indicated patients were WHO obesity class I-II, or III, where patients refused a surgical approach.

RESULTS

Between February 28, 2011 and March 23, 2012, the POSE procedure was successfully performed in 45 patients: 75.6 % female; mean age 43.4 ± 9.2 SD (range 21.0-64.0). At baseline: mean absolute weight (AW, kg), 100.8 ± 12.9 (75.5-132.5); body mass index (BMI, kg/m(2)), 36.7 ± 3.8 (28.1-46.6). A mean 8.2 suture-anchor plications were placed in the fundus, 3.0 along the distal body wall. Mean operative time, 69.2 ± 26.6 min (32.0-126.0); patients were discharged in <24 h. Six-month mean AW was 87.0 ± 10.3 (68.0-111.5); BMI decreased 5.8 to 31.3 ± 3.3 (25.1-38.6) (p < 0.001); EWL was 49.4 %; TBWL, 15.5 %. No mortality or operative morbidity. Minor postoperative side effects resolved with treatment by discharge. Patients reported less hunger and earlier satiety post procedure. Liquid intake began 12 h post procedure with full solids by 6 weeks.

CONCLUSIONS

At 6-month follow-up of a prospective case series, the POSE procedure appeared to provide safe and effective weight loss without the scarring, pain, and recovery issues of open and laparoscopic bariatric surgery. Long-term follow-up and further study are required.

The von willebrand factor A3 domain does not contain a metal ion-dependent adhesion site motif

von Willebrand factor (vWF) is a multimeric plasma protein that mediates platelet adhesion to exposed subendothelium at sites of vascular injury. The A3 domain of vWF (vWF-A3) forms the principal binding site for collagens type I and III. We report here the crystal structure of the vWF-A3 domain at 2.2-A resolution. As expected, the structure is similar to the integrin I domain but with several novel features. Sequence alignments had suggested that the domain contained an integrin metal ion-dependent adhesion site (MIDAS) motif, but the crystal structure shows that the motif is modified and that no metal ion is bound. We have introduced mutations into the vestigial MIDAS motif and report that, unlike the I domain of integrin alpha2beta1, vWF-A3 continues to bind collagen after disruption of the motif. We conclude that collagen recognition by vWF-A3 occurs by a mechanism different from that of the integrin alpha2beta1.

Immunoblot detection of oligoclonal anti-myelin basic protein IgG antibodies in cerebrospinal fluid in multiple sclerosis

Migration properties and occurrence of antibodies against myelin basic protein (MBP) in paired CSF and serum specimens from patients with multiple sclerosis (MS) were demonstrated after agarose isoelectric focusing, immunoblot transfer, and immunoperoxidase staining. Oligoclonal IgG antibody bands directed against MBP were found in the CSF of 9 of 28 patients with MS (32%), but not in the CSF of any of 34 patients with other neurologic diseases. No serum showed anti-MBP antibody bands. The CSF anti-MBP antibodies migrated to the anodal region of the IgG area in a different fashion from oligoclonal IgG and anti-measles IgG antibodies, which were detected in parallel. The anti-MBP bands were transient in three of seven patients whom we studied consecutively. Enzyme-linked immunosorbent assay (ELISA) of serum and CSF for detection of IgG reactivity against MBP showed absorbance values above 2 standard deviations of controls in 44% of the MS patients and in 21% of those with other neurologic diseases. Results of this assay correlated partly with those of the immunoblot assay. ELISA positive and immunoblot negative results might be due to a broad polyclonal anti-MBP antibody response.

Mode of Chemical-Degradation of s-Triazines by Montmorillonite

Chemical hydrolysis of the s-triazines after interaction with less than 2-micron (equivalent spherical diameter) montmorillonite clay occurs as a result of protonation at the colloidal surface; protonation occurs even when the exchange sites are occupied by metallic cations. The adsorbed hydrolytic degradation product is not the hydroxy analog, but it is predominantly the keto form of the protonated hydroxy species. This cationic form is held tightly by the clay which may restrict vertical movement and entrance into groundwater. Protonation of the hydroxy analog occurs on the heterocyclic ring nitrogen.

Candidate gene association study conditioning on individual ancestry in patients with type 2 diabetes and metabolic syndrome from Mexico City

BACKGROUND

Type 2 diabetes (T2D) is influenced by diverse environmental and genetic risk factors. Metabolic syndrome (MS) increases the risk of cardiovascular disease and diabetes. We analysed 14 cases of polymorphisms located in 10 candidate loci, in a sample of patients with T2D and controls from Mexico City.

METHODS

We analysed the association of 14 polymorphisms located within 10 genes (TCF7L2, ENPP1, ADRB3, KCNJ11, LEPR, PPARgamma, FTO, CDKAL1, SIRT1 and HHEX) with T2D and MS. The analysis included 519 subjects with T2D defined according to the ADA criteria, 389 with MS defined according to the AHA/NHLBI criteria and 547 controls. Association was tested with the program ADMIXMAP including individual ancestry, age, sex, education and in some cases body mass index (BMI), in a logistic regression model.

RESULTS

The two markers located within the TCF7L2 gene showed strong associations with T2D (rs7903146, T allele, odd ratio (OR) = 1.76, p = 0.001 and rs12255372, T allele, OR = 1.78, p = 0.002), but did not show significant association with MS. The non-synonymous rs4994 polymorphism of the ADRB3 gene was associated with T2D (Trp allele, OR = 0.62, p = 0.001) and MS (Trp allele, OR = 0.74, p = 0.018). Nominally significant associations were also observed between T2D and the SIRT1 rs3758391 SNP and MS and the HHEX rs5015480 polymorphism.

CONCLUSIONS

Variants located within the gene TCF7L2 are strongly associated with T2D but not with MS, providing support to previous evidence indicating that polymorphisms at the TCF7L2 gene increase T2D risk. In contrast, the non-synonymous ADRB3 rs4994 polymorphism is associated with T2D and MS.

Respiratory-related evoked potentials in children with life-threatening asthma

Respiratory-related evoked potentials (RREPs) have been elicited by inspiratory occlusion and recorded over the somatosensory cortex. The first positive peak (P(1)) amplitude has been correlated with the magnitude of inspiratory loads. Since children with life-threatening asthma (LTA) have a decreased perceptual sensitivity of inspiratory loads, we hypothesized that a subpopulation of patients with LTA have an impaired ability to sense mechanical loads, and that these patients would have an abnormal RREP. The RREP was recorded from C(Z) -C(3) and C(Z) -C(4) in three groups: LTA asthmatic, control asthmatic, and nonasthmatic children. Two inspiratory-interruption occlusions trials and a control trial were recorded. All the evoked potentials were analyzed after the averaged control trial was subtracted from the averaged occlusion trials. The RREP P(1) peak was observed in all 14 nonasthmatic children and in 14 of 15 control asthmatic children. The RREP was absent in 6 of 11 patients with LTA. When present, there were no between-group significant differences in P(1) peak latency or amplitude. These results demonstrate that the RREP elicited by inspiratory occlusion is present bilaterally in nonasthmatic and asthmatic children. There is a subpopulation of LTA children in which inspiratory occlusion fails to elicit the P(1) peak of the RREP, suggesting an altered neural processing of inspiratory load information.

Glycine treatment decreases proinflammatory cytokines and increases interferon-gamma in patients with type 2 diabetes

BACKGROUND

Amino acids have been shown to stimulate insulin secretion and decrease glycated hemoglobin (A1C) in patients with Type 2 diabetes. In vitro, glycine reduces tumor necrosis factor (TNF)-alpha secretion and increases interleukin-10 secretion in human monocytes stimulated with lipopolysaccharide. The aim of this study was to determine whether glycine modifies the proinflammatory profiles of patients with Type 2 diabetes.

MATERIALS/SUBJECTS AND METHODS

Seventy-four patients, with Type 2 diabetes were enrolled in the study. The mean age was 58.5 yr, average age of diagnosis was 5 yr, the mean body mass index was 28.5 kg/m2, the mean fasting glucose level was 175.5 mg/dl and the mean A1C level was 8%. They were allocated to one of two treatments, 5 g/d glycine or 5 g/d placebo, po tid, for 3 months.

RESULTS

A1C levels of patients given glycine were significantly lower after 3 months of treatment than those of the placebo group. A significant reduction in TNF-receptor I levels was observed in patients given glycine compared with placebo. There was a decrease of 38% in the interferon (IFN)-gamma level of the group treated with placebo, whereas that of the group treated with glycine increased up to 43%. These data showed that patients treated with glycine had a significant decrease in A1C and in proinflammatory cytokines and also an important increase of IFN-gamma.

CONCLUSION

Treatment with glycine is likely to have a beneficial effect on innate and adaptive immune responses and may help prevent tissue damage caused by chronic inflammation in patients with Type 2 diabetes.

Characterization of low-intensity lesions in the peripheral zone of prostate on pre-biopsy endorectal coil MR imaging

The aim of this study was to determine which morphological features of low-intensity lesions in the peripheral zone of the prostate are predictable of prostate cancer on pre-biopsy T2-weighted integrated endorectal phased-array MR images. The MR examinations were performed in 69 consecutive patients with elevated level of prostate-specific antigen (>4 ng/ml) and/or a positive digital rectal examination before transperineal 12-site biopsy. Two radiologists evaluated presence of lesions, their morphological features, and possibility of malignancy in divided into four sections of the peripheral zone. Imaging analysis findings were compared with biopsy results. Discriminative features were selected by stepwise logistic regression. Descriptive statistics and receiver operating characteristics (ROC) curves were also calculated. Sixty-eight benign lesions and 23 malignant lesions were found. Wedge shape and diffuse extensions without mass effect were significantly associated with benignity ( P=0.0105 and 0.002, respectively). Lesion size was significantly associated with malignancy ( P=0.0001). For evaluating probability of malignancy for lesions, regression model showed a comparable accuracy with the total impression for the readers in ROC analysis (Az 0.9095 vs 0.9266, respectively). Wedge shape, diffuse extension without mass effect, and size are the morphological features of low-intensity lesions in the peripheral zone on pre-biopsy T2-weighted MR images that give the best prediction of malignancy.

Clinical, neurophysiological and immunological evidence of polyneuropathy in patients with monoclonal gammopathies

In this study we estimated the prevalence of polyneuropathy (PN) in patients with monoclonal gammopathies. 31 patients with monoclonal gammopathies (19 with monoclonal gammopathy of uncertain significance (MGUS), 10 with multiple myeloma (MM), and 2 with Waldenström's macroglobulinemia), were studied by clinical and neurophysiological examination, blood tests to exclude other causes of PN, ELISA assays to detect antibodies to peripheral nerve myelin (PNM), and antibodies to myelin associated glycoprotein (MAG). 11 of 31 patients (36%) had a clinical PN, 3 (10%) had a probable PN (signs but no symptoms), and 4 (13%) had a subclinical PN (only neurophysiological signs of PN). Thus, in total 18 patients (58%) had some form of PN, in contrast to an age-matched control group (n = 33) where only 2 persons (6%) had some form of PN; 1 had a probable PN and 1 had a subclinical PN. 3 patients had anti-PNM and anti-MAG antibodies of IgM isotype, all 3 patients showing a demyelinating PN. The remaining patients with PN had a mild or moderate distal PN. One patient had a myelopathy and 1 had amyotrophic lateral sclerosis (ALS). IgM isotype of the M-protein was associated with a high risk of clinical PN (5 out of 6 (83%)), in contrast to IgG (5 out of 18 (28%)) and IgA (1 out of 6 (17%)). We conclude that PN is a common finding in patients with monoclonal gammopathies, but only some of them are of the demyelinating type and associated with antibodies to PNM or MAG.

Tracking of oocyte dysmorphisms for ICSI patients may prove relevant to the outcome in subsequent patient cycles

BACKGROUND

We determined whether oocyte dysmorphisms, especially repetition of specific dysmorphisms from cycle to cycle, had a prognostic impact on intracytoplasmic sperm injection (ICSI) outcome.

METHODS

ICSI patients (n = 67) were grouped as follows: group 1 >50% phenotypically dysmorphic oocytes per cohort (cytoplasmic and extra-cytoplasmic dysmorphisms) with no repetition of a specific dysmorphism from cycle one to cycle two (36 cycles and 274 oocytes); group 2 >50% dysmorphic oocytes per cohort and repetition of the same dysmorphism from cycle one to cycle two (32 cycles and 313 oocytes); group 3 (control) <30% dysmorphic oocytes (33 cycles and 378 oocytes).

RESULTS

In group 2 (repetitive), 47% of oocytes were observed to have organelle clustering versus 20.5% in group 1 and 17.3% in group 3 (P < 0.001). There was no difference between the groups in fertilization rates, cleavage rates or embryo quality. Embryos derived from normal oocytes were transferred in each group (57, 33 and 72% respectively). The clinical pregnancy and implantation rates in group 2 (3.1 and 1.7% respectively) were lower (P < 0.01, P = 0.005) than both group 1 (28 and 15% respectively) and group 3 (45.5 and 26.5% respectively).

CONCLUSIONS

The low implantation rate in group 2, even though 33% of transferred embryos were derived from morphologically normal oocytes, suggests that repetitive organelle clustering may be associated with an underlying adverse factor affecting the entire follicular cohort.

Stenting as first option for endovascular treatment of malignant superior vena cava syndrome

OBJECTIVE

Endoprostheses were inserted in cancer patients with superior vena cava syndrome to assess their effectiveness as first-choice, initial treatment for relief of symptoms.

SUBJECTS AND METHODS

Wallstent prostheses (n = 73) of various lengths (5-14 cm; median, 7 cm) and diameters (10-16 mm; median, 16 mm) were inserted in 52 cancer patients (51 men, 1 woman; age range, 44-78 years; mean, 63 years) who were diagnosed and confirmed by cavography or phlebography as having superior vena cava syndrome. A single stent was sufficient in 37 patients, two stents were required in 11, three stents in two, and four stents in another two patients. Contraindications for the procedure were severe cardiopathy or coagulopathy.

RESULTS

Resolution of symptoms was achieved in all patients within 72 hr. At follow-up, six obstructions, one partial migration to the right atrium, two incorrect placements, and four stent "shortenings" were noted. All were successfully resolved by repeated stenting. Symptom-free survival ranged from 2 days to 17 months (mean, 6.4 months). At the time of this writing, eight patients are alive and have patent stents. The rest have died from their cancer.

CONCLUSION

The Wallstent vascular endoprosthesis is an effective initial treatment in superior vena cava syndrome of neoplastic origin. Morbidity and complications are minimal. Clinical relief of symptoms is rapid; therefore, the Wallstent endoprosthesis is highly recommended as the first choice for palliative treatment of superior vena cava syndrome, especially because the clinical decision for subsequent chemotherapy or radiotherapy or surgery is not in any way prejudiced.

Oligoclonal Borrelia burgdorferi-specific IgG antibodies in cerebrospinal fluid in Lyme neuroborreliosis

Cerebrospinal fluid (CSF) and serum from 45 patients with lymphocytic meningoradiculitis were examined by isoelectric focusing combined with immunoblotting to detect Borrelia burgdorferi-specific oligoclonal immunoglobulin G (IgG) bands. In pretreatment samples, 35 patients (78%) showed B. burgdorferi-specific oligoclonal IgG in CSF indicative of intrathecal antibody production. At 2, 3-6, and 6 weeks after onset, respectively, such bands were present in 5 (42%) of 12, 21 (88%) of 24, and in all of 9 patients (100%). Up to 1 year after therapy, specific oligoclonal bands in CSF tended to remain unchanged despite clinical recovery. B. burgdorferi-specific oligoclonal bands in serum were found in 7 patients. These bands had identical migration patterns as in CSF, but were fewer in number and in some patients showed a temporal evolution different from their CSF counterpart. Not all oligoclonal IgG in CSF reacted with B. burgdorferi. The 41-kDa flagellar antigen was shown to be a major antigen in the intrathecal immune response. The demonstration of B. burgdorferi-specific oligoclonal IgG in CSF is a sensitive and reliable indicator of Lyme neuroborreliosis.

Leukocyte kinetics in the human lung: role of exercise and catecholamines

In six normal supine subjects epinephrine infusion produced a greater leukocytosis with smaller changes in heart rate and blood pressure than did norepinephrine or isoproterenol. Upright exercise in those subjects produced a greater leukocytosis than supine exercise at the same work load. To determine the lung's participation in these events, indium-labeled neutrophils (PMN) were given to four of the subjects. We found that 20-25% were retained in the first pass through the lung when compared with technetium-labeled erythrocytes. The number of labeled PMN in the lung gradually decreased and the number in the spleen and the liver increased. Exercise and catecholamine infusion caused an acceleration in the release of labeled cells from the lung, an increase in both labeled and unlabeled cells in the peripheral blood, and an increase in the number of labeled cells in the liver and spleen. This suggests that increased perfusion of low-flow areas in the lung may contribute to the increased leukocytosis seen in association with both exercise and catecholamine infusion.

Immunoglobulin abnormalities in cerebrospinal fluid and blood over the course of lymphocytic meningoradiculitis (Bannwarth's syndrome)

The conditions of 5 patients with untreated lymphocytic meningoradiculitis (Bannwarth's syndrome, probably equivalent to Lyme disease) with serologically confirmed infection resulting from Borrelia spirochetes were followed with repetitive lumbar punctures up to 221 days after the onset of symptoms. Using a protein A plaque assay, high numbers of IgG-, IgM-, and IgA-producing cells were found in the cerebrospinal fluid (CSF), whereas there were mostly normal numbers of immunoglobulin-producing cells in peripheral blood. A markedly increased CSF IgM index and an elevated IgG index were observed in all patients during the early phase, reflecting production of these immunoglobulins within the central nervous system. All patients had oligoclonal IgG bands in the CSF that persisted during follow-up; in the 2 patients tested, the bands contained Borrelia antibodies. Most serum immunoglobulin concentrations were normal and in only 1 patient was it possible to detect in serum some of the oligoclonal IgG bands present in CSF. Declining numbers of CSF cells producing immunoglobulin and decreasing immunoglobulin index values were observed during follow-up, but 3 patients had an elevated CSF IgM index in the presence of normal IgG and IgA indices when examined during the later phases of disease. An intense and prolonged IgM response within the central nervous system seems to be a characteristic of the disease.

Efficacy of intravenously administered theophylline in children hospitalized with severe asthma

PURPOSE

To determine whether intravenously administered theophylline, when added to frequently nebulized albuterol and intravenously administered methylprednisolone, benefits children hospitalized with severe asthma.

DESIGN

Prospective, randomized, placebo-controlled, parallel-group, double-blind study.

SETTING

Inpatient pediatric service at a tertiary-care teaching hospital.

PATIENTS

Twenty-one children 5 to 18 years of age.

INTERVENTIONS

All patients received 2.5 to 5.0 mg of nebulized albuterol every 20 minutes to every 6 hours, intravenously administered methylprednisolone (1 mg/kg every 6 hours), and either intravenously administered theophylline (as aminophylline) or placebo for 36 hours. Serum theophylline concentrations were maintained between 55 and 110 mumol/L (between 10 and 20 micrograms/ml) by adjusting loading doses and continuous infusion rates.

MEASUREMENTS AND MAIN RESULTS

Forced expired volume in 1 second (FEV1) and clinical score were measured at 0, 1, 3, 6, 12, 24, and 36 hours after the start of each individual study. The total number of nebulizations, total albuterol dosage, adverse effects, and duration of hospital stay were recorded. Twelve children received theophylline and nine received placebo. The two groups did not differ significantly in age, sex, or baseline FEV1. In both groups, clinical score significantly improved from baseline by 12 hours, and FEV1 by 24 hours (p < 0.05). There were no significant differences between the groups in FEV1 or clinical score at any of the measured time points. There were no significant differences in rate of improvement in FEV1, total number of nebulizations, total albuterol dosage, or duration of hospital stay. Adverse effects were mild and infrequent and did not differ significantly between the two groups.

CONCLUSIONS

Theophylline, at therapeutic concentrations, did not additionally benefit children hospitalized with severe asthma who were being treated frequently with nebulized albuterol and with methylprednisolone intravenously.

Th1-type cytokines improve resistance to murine cysticercosis caused by Taenia crassiceps

Resistance and susceptibility to different parasitic diseases have been associated with the predominance of Th1- or Th2-type immune responses. In experimental murine cysticercosis a Th1 response seems to be involved in resistance, whereas Th2 activity is associated with heavy parasite intensities. To test this notion the roles of Th1- and Th2-type cytokines in infected mice were studied after treatment with anticytokine monoclonal antibodies or with recombinant murine cytokines during early stages of infection. Mice receiving anti-interleukin 10 (IL-10) carried lower parasite intensities than did control mice and developed a strong Th1-type response, whereas mice receiving anti-interferon gamma (IFN-gamma) showed a dramatic increase in susceptibility. Treatment with recombinant cytokines confirmed these results; mice receiving IFN-gamma and IL-2 showed low parasite numbers, whereas IL-10 induced a significant increase in parasite loads. Thus, the Th1-type immune response plays a fundamental role in protection against Taenia crassiceps cysticercosis, whereas Th2, at least through IL-10, favors parasite establishment.