Levamisole-associated multifocal inflammatory encephalopathy: clinical and MRI characteristics, and diagnostic algorithm

Levamisole-associated multifocal inflammatory encephalopathy (LAMIE) is a devastating adverse effect of levamisole (LEV) treatment. In Russia, people often use LEV without a doctor's prescription for anthelmintic prophylaxis. LAMIE often misdiagnosed as the first episode of MS or acute disseminated encephalomyelitis (ADEM). The aim of our study was to describe clinical, laboratory and morphological characteristics of LAMIE, magnetic resonance imaging (MRI) patterns and create an algorithm for the differential diagnosis. This study was a prospective observational study with retrospective analysis of cases. It was performed at two hospitals with ambulatory service for MS. We included 43 patients with LAMIE with follow-up was from 1 year to 5 years. Age was 19-68 y.o. with female predominance. The most typical manifestations of LAMIE were cerebellar, pyramidal and cognitive symptoms, and majority of patients had biphasic course of the disease. Three main types of MRI patterns were described: ADEM-like, MS-like, atypical demyelination. About 40% of patients had CSF specific oligoclonal bands synthesis, but only 20 % of them converted to MS during the period from 1 month until 2 years. The CSF albumin levels and immunoglobulin G index were elevated in LAMIE patients compared to reference values. We described results of brain biopsy in two cases. Therefore LAMIE should be considered in patients with demyelinating or inflammatory conditions with biphasic onset of the disease and variable MRI presentation.

New diagnostic index for prediction of severe irAEs in patients with metastatic melanoma taking checkpoint inhibitors

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Background: Immune-related adverse events (irAEs) occur in up to 50% of patients treated with immune checkpoint inhibitors (ICI). Severe forms of toxicity are observed in 3% of patients and require systemic steroid therapy and constant monitoring. One of the considered predictor biomarkers of irAEs development is HLA-genotypes. This research aims to evaluate the diagnostic significance of HLA-DRB1 genotypes and other clinical, laboratory parameters to predict the development of irAEs. Methods: The study involved 28 patients (pts) with metastatic melanoma taking ICI (nivo 53.6%, ipi+nivo 32.1%, other 14.3%). The PD-L1 expression, HLA-DRB1 genotype were evaluated. After 2-3 months the development of irAES was assessed. The complications of 3-4 grade or multi-organ damage were termed as a severe irAEs. Statistical analysis was performed in GraphPad Prism 6 (Graph Pad Software, USA) using Fisher, Mann-Whitney, ROC statistical analysis. The project is supported by a grant (14. W03.31.0009). Results: Different IrAEs developed in 57.1% (16/28) of patients, while severe irAEs in 35.7% (10/28). Among all patients HLA-DRB1 genotypes associated with the risk of autoimmune diseases were found in 78.5% (22/28). The PD-L1 expression was detected in 60.7% (17/28) of individuals.Combination treatment increases the risk of toxicity, p = 0.003, with a diagnostic sensitivity (S) of 56% and a diagnostic specificity (Sp) of 100% (RR = 2.71, OR = 31.67). The analysis of specific complications revealed associations between HLA-DRB1*04 with diabetes mellitus, p = 0.026 (OR = 33.57, S = 100%, Sp = 88.5%), HLA-DRB1*04/15 with autoimmune hepatitis or increased transaminases, p = 0.037 (OR = 17.27, S = 100%, Sp = 72%). An index based on the parameters studied (HLA-DRB1, the absence of PD-L1 expression, type of treatment) was created. With index value ≥2 a sensitivity for predicting severe toxicity is 40.00% and a specificity is 83.33%, p = 0.0126. Conclusions: According to the results obtained it can be assumed that the development of severe forms of irAES has a multifactorial origin, in particular, combination therapy, the absence of PD-L1 expression, which can lead to the loss of ICI drug specificity, and the presence of HLA-DRB1 genotypes associated with the risk of developing autoimmune diseases. The new diagnostic index to predict severe complications based on these parameters was created and showed a sensitivity of 40.00% and a specificity of 83.33%. The authors consider the limitations of the study, such as the small sample, the short observational period.

The novel diagnostic index based on HLA-DRB1 genotype and PD-L1 expression can predict severe irAEs in patients with metastatic melanoma taking immune checkpoint inhibitors

Immune-related adverse events (irAEs) occur in up to 50% of patients treated with an anti-CTLA-4 antibody and 30% of patients treated with PD-1/PD-L1 antibodies. Severe forms of toxicity are observed in 3% of patients and require systemic steroid therapy and constant monitoring. One of the considered predictor biomarkers of irAEs development is HLA-genotypes. This research aims to evaluate the diagnostic significance of HLA-DRB1 genotypes and other clinical and laboratory parameters to predict the development of irAEs. The study involved 28 patients with metastatic melanoma taking checkpoint inhibitors therapy [nivo 53.6%, Ipi+nivo 32.1%, other (pembro, prolgo) 14.3%]. The PD-L1 expression and HLA-DRB1 genotype were evaluated. After 2-3 months the development of irAES was assessed. The complications of 3-4 grade or multi-organ damage were termed as severe irAEs. Various IrAEs developed in 57.1% (16/28) of patients, while severe irAEs occurred in 35.7% (10/28). Among all patients, HLA-DRB1 genotypes associated with the risk of autoimmune diseases were found in 78.5% (22/28). The PD-L1 expression was detected in 60.7% (17/28) of individuals. Combination treatment increases the risk of toxicity, p = 0.0028, with a diagnostic sensitivity of 56% and a diagnostic specificity of 100% (RR = 2.71, OR = 31.67). An index based on the parameters studied (HLA-DRB1, absence of PD-L1 expression, and type of treatment) was created. It allows assuming the risk of developing severe irAES (p = 0.0126). When comparing this indicator between irAEs 1-2 and irAEs 3-4, the presence of an index value of more than 2 gives a sensitivity for predicting severe toxicity of 40.00% and a specificity of 83.33%.

SAT0533 ADULT ONSET STILLS DISEASE AND IDIOPATHIC RECURRENT PERICARDITIS: ARE THE MORE SIMILARITIES OR DIFFERENCES?

Background:

Adult onset Stills disease (AOSD) and Idiopathic recurrent pericarditis (IRP) are currently considered auto-inflammatory diseases. Common features of these disorders are symptoms such as fever, leukocytosis, serositis, increased acute phase reactants.

Diagnosis of IRP is based on ESC 2015 diagnostic criteria, while AOSD is defined according to 3 sets of classification criteria. A detailed study shows that modern criteria for these nosologies overlap and do not allow distinguishing one from the other.

Objectives:

We have not found any data on the comparison of the two groups in the literature. We compared the two groups of patients according to several parameters, such as clinical features, laboratory testing, genetic analysis to identify common patterns.

Methods:

We enrolled 22 newly identified subjects (13 patients with AOSD, 9 patients with IRP) to our prospective, monocenter study. The mean age of patients with AOSD was 31 [22; 39], the mean age of patients with IRP was 46 [35;54]. Blood sampling in all patients was performed in the flare.

We quantified the serum levels of ferritin and its glycosylated fraction in both groups. Mutations of the MEFV, TNFRSF1A genes were studied. As more sensitive imaging methods for lymphadenopathy and serositis, we performed the following instrumental studies for all patients: transthoracic echocardiography, ultrasound of the abdominal cavity and pelvis, chest high-resolution computed tomography.

Results:

One subject with a heterozygous missense variant was found in exon

2 of the MEFV gene (E148Q) in the IRP group. The patient was excluded from our study. Elevated white blood cell (WBC) count and C-reactive protein (CRP) were observed in all patients in 2 groups, however, the level of WBC greater than 10,000/mm3was found only in 10 patients from the AOSD group and 5 – from the IRP. Elevated ferritin level in both groups was detected. The number of subjects with high level of ferritin in the AOSD group reached 12 (n=13), in the IRP group – 7 (n=8).

The ferritin level appeared to be more significant in the AOSD group compared to the IRP group (1521 ng/ml vs 408 ng/ml p=0.0159) Figure 1.In turn, lower glycosylated ferritin was recorded in 9 patients with AOSD (n=13), and 7 – with IRP (n=8). We have demonstrated a more significant decrease of glycosylated ferritin level in patients with AOSD in comparison to patients with IRP, which amounted (11% vs 37% p = 0.0286) reference value (38.6%-84.7%). Figure 1.

Abnormal liver function tests were found in the majority of patients with AOSD and IRP (61% vs 75%).

We have also shown that, if the patient had pericardial effusion, the fluid was present in the pleural cavity, regardless of the group.

The number of AOSD patients with polyserositis was 5 (n=13).

Other symptoms are presented in Table 1

Table 1Symptom and signAOSD (n=13)IRP (n=8)CRP mg/L, mean, %123 [69;164], 100%151[65; 226], 100%Pericarditis38%100%Pleuritis38%100%Leukocytosis ≥10,000/mm377%62%Abnormal liver function tests61%75%Fever >39 °C100%100%Rush77%0 %Arthralgia100%75%Arthritis, lasting 2 weeks or longer100%12.5%Sore throat54%0%Recent lymphadenopathy85%25%Hepatomegaly or splenomegaly54%62%Elevated ferritin92%87%Glycosylated ferritin ≤20%69%25%

Conclusion:

The level of ferritin in the IRP group was lower, which can be explained by a less generalized process, the absence of such symptoms as arthritis, rash, splenomegaly.

Diagnostic and classification criteria of both disorders do not allow distinguishing between the diseases.

There might be no differences between the diseases; further research (on more representative groups) is needed. We consider the comparison of the gene-expression analysis in these patients to be of great importance.

Disclosure of Interests:

None declared

Trends in the incidence of childhood-onset type 1 diabetes in Slovakia 1985 - 2000

The aim of this work was to study and monitor the patterns in incidence of childhood type 1 diabetes in Slovakia. The incidence of type 1 diabetes per 100,000/year from 1985 to 2000 was determined in children 0 - 14 years old. A total of 1,818 cases were diagnosed during this time. Poisson regression models were used to study incidence trends. The overall incidence of type 1 diabetes varied from 5.62/100,000 per year in year 1986 to 14.46/100,000 in year 1998. This represents a 2.57-fold increase. The incidence increased with age and was the highest among children 10 - 14 years of age. The incidence of type 1 diabetes in Slovakia is increasing very dramatically, especially in age group 0 - 4 years.

Probing weak forces in granular media through nonlinear dynamic dilatancy: clapping contacts and polarization anisotropy

Rectification (demodulation) of high-frequency shear acoustic bursts is applied to probe the distribution of contact forces in 3D granular media. Symmetry principles allow for rectification of the shear waves only with their conversion into longitudinal mode. The rectification is due to nonlinear dynamic dilatancy, which is found to follow a quadratic or Hertzian power law in the shear wave amplitude. Evidence is given that a significant portion of weak contact forces is localized below 10(-2) of the mean force-a range previously inaccessible by experiment. Strong anisotropy of nonlinearity for shear waves with different polarization is observed.

Extracellular pH, Ca(2+) influx, and response of vascular smooth muscle cells to 5-hydroxytryptamine

BACKGROUND AND PURPOSE

Cerebral vascular smooth muscle cells (VSMCs) contract on extracellular pH (pH(o)) increases and relax on pH(o) decreases. These changes in tone are believed to result from changes in [Ca(2+)](i), although the responsible mechanisms are not fully understood. VSMCs also contract in response to 5-hydroxytryptamine (5-HT), which increases [Ca(2+)](i) via both Ca(2+) release and influx. We hypothesized that examining effects of pH(o) decreases on 5-HT-induced [Ca(2+)](i) changes would allow us to identify mechanisms whereby pH(o) influences tone. Accordingly, we compared [Ca(2+)](i) increases in cerebral VSMCs, evoked by 5-HT, with increases evoked by increased pH(o) and examined 5-HT-dependent [Ca(2+)](i) increases at normal and decreased pH(o).

METHODS

We monitored [Ca(2+)](i,), using the Ca(2+)-sensitive dye fura 2, in cultured rat cerebral VSMCs obtained by enzymatic digestion of middle cerebral arteries and their branches (passages 1 to 3) grown on glass coverslips and superfused with physiological saline.

RESULTS

Increasing pH(o) from 7.3 to 7.8 increased [Ca(2+)](i), and these increases were prevented in Ca(2+)-free solutions. Decreasing pH(o) from 7.3 to 6.9 did not alter [Ca(2+)](i) unless [Ca(2+)](i) was first raised by treatment with 5-HT (10 micromol/L). 5-HT resulted in biphasic [Ca(2+)](i) increases characterized by transient peaks blocked by the Ca(2+)-ATPase inhibitor thapsigargin (10 nmol/L) and prolonged plateaus blocked by the Ca(2+) channel blocker Ni(2+) (1 mmol/L). Acidification did not alter the transient peaks but significantly reduced 5-HT-induced Ca(2+) influx.

CONCLUSIONS

We conclude that increasing pH(o) induces Ca(2+) influx in rat cerebral VSMCs and decreasing pH(o) inhibits 5-HT-stimulated Ca(2+) entry but not intracellular Ca(2+) release.

Regulation of the resident chromosomal copy of c-myc by c-Myb is involved in myeloid leukemogenesis

c-myb is a frequent target of retroviral insertional mutagenesis in murine leukemia virus-induced myeloid leukemia. Induction of the leukemogenic phenotype is generally associated with inappropriate expression of this transcriptional regulator. Despite intensive investigations, the target genes of c-myb that are specifically involved in development of these myeloid lineage neoplasms are still unknown. In vitro assays have indicated that c-myc may be a target gene of c-Myb; however, regulation of the resident chromosomal gene has not yet been demonstrated. To address this question further, we analyzed the expression of c-myc in a myeloblastic cell line, M1, expressing a conditionally active c-Myb-estrogen receptor fusion protein (MybER). Activation of MybER both prevented the growth arrest induced by interleukin-6 (IL-6) and rapidly restored c-myc expression in nearly terminal differentiated cells that had been exposed to IL-6 for 3 days. Restoration occurred in the presence of a protein synthesis inhibitor but not after a transcriptional block, indicating that c-myc is a direct, transcriptionally regulated target of c-Myb. c-myc is a major target that transduces Myb's proliferative signal, as shown by the ability of a c-Myc-estrogen receptor fusion protein alone to also reverse growth arrest in this system. To investigate the possibility that this regulatory connection contributes to Myb's oncogenicity, we expressed a dominant negative Myb in the myeloid leukemic cell line RI-4-11. In this cell line, c-myb is activated by insertional mutagenesis and cannot be effectively down regulated by cytokine. Myb's ability to regulate c-myc's expression was also demonstrated in these cells, showing a mechanism through which the proto-oncogene c-myb can exert its oncogenic potential in myeloid lineage hematopoietic cells.

Identification of protein instability determinants in the carboxy-terminal region of c-Myb removed as a result of retroviral integration in murine monocytic leukemias

The c-myb oncogene has been a target of retroviral insertional mutagenesis in murine monocytic leukemias. One mechanism by which c-myb can be activated is through the integration of a retroviral provirus into the central portion of the locus, causing premature termination of c-myb transcription and translation. We had previously shown that a leukemia-specific c-Myb protein, truncated at the site of proviral integration by 248 amino acids, had approximately a fourfold-increased half-life compared to the normal c-Myb protein, due to its ability to escape rapid degradation by the ubiquitin-26S proteasome pathway. Here we provide evidence for the existence of more than one instability determinant in the carboxy-terminal region of the wild-type protein, which appear to act independently of each other. The data were derived from examination of premature termination mutants and deletion mutants of the normal protein, as well as analysis of another carboxy-terminally truncated protein expressed in leukemia. Evidence is provided that one instability determinant is located in the terminal 87 amino acids of the protein and another is located in the vicinity of the internal region that has leucine zipper homology. In leukemias, different degrees of protein stability are attained following proviral integration depending upon how many determinants are removed. Interestingly, although PEST sequences (rich in proline, glutamine, serine, and threonine), often associated with degradation, are found in c-Myb, deletion of PEST-containing regions had no effect on protein turnover. This study provides further insight into how inappropriate expression of c-Myb may contribute to leukemogenesis. In addition, it will facilitate further studies aimed at characterizing the specific role of individual regions of the normal protein in targeting to the 26S proteasome.

Mml1, a new common integration site in murine leukemia virus-induced promonocytic leukemias maps to mouse chromosome 10

MuLV-induced myeloid leukemias (MML) having promonocytic characteristics are produced with high incidence in some strains of adult mice that are undergoing chronic peritoneal inflammation. Previously we showed that many leukemias have rearrangements of the c-myb locus due to insertional mutagenesis, however, we also identified a number of leukemias that had proviral integrations in the absence of c-myb rearrangement in the present study, a new locus, Mml1, was found to be a target of insertional mutagenesis in 10 of the promonocytic leukemias that lacked c-myb alterations. Chromosomal mapping studies, performed using progeny from interspecies backcross mice generated by mating (BALB/cAn x M. spretus)F1 females to BALB/cAN males, determined that Mml1 is located on the proximal end of mouse chromosome 10. Interestingly, there were no recombinants between c-myb and Mml1 in 101 backcross progeny and Mml1 was mapped approximately 20-25 kb upsteam of c-myb. Interestingly, c-myb mRNA and Myb protein are expressed at levels similar to the levels observed in myeloid progenitor cells, but are not overexpressed. It is anticipated that future experiments will determine whether Mml1 integration prevents down regulation of c-myb expression or activates another gene on chromosome 10.

Retroviral insertional mutagenesis in murine promonocytic leukemias: c-myb and Mml1

Studies have focused on two genetic loci, c-myb and Mml1, whose activation by retroviral insertional mutagenesis contribute to promonocytic leukemia in our acute monocytic leukemia (AMoL) model. Multiple mechanisms of activation of c-myb by retroviral insertional mutagenesis implicate both transcriptional deregulation and protein truncation in conversion of this proto-oncogene to an oncogene. Because transformation by c-Myb can be viewed as a block to differentiation our studies moved into two in vitro systems to evaluate effects of truncated forms of c-Myb on cytokine induced maturation of myeloid progenitors to the granulocyte and macrophage lineages. Deregulated expression of truncated and full length c-Myb did not result in maintenance of the myelomonocytic progenitor state but rather a block in differentiation at intermediate to late steps in the maturation processes of myelomonocytic cells. Our results argue that inhibition of differentiation is due to c-Myb's ability to maintain the proliferative state of cells. Interestingly, the phenotype of continuously proliferating monocytic cells resembles that of the tumor cell phenotype. Recently we identified a new target of integration, Mml1, which is rearranged in ten promonocytic leukemias that do not have c-myb rearrangements. This locus which was mapped to chromosome 10 is presently being characterized.

Proviral activation of the c-myb proto-oncogene is detectable in preleukemic mice infected neonatally with Moloney murine leukemia virus but not in resulting end stage T lymphomas

Moloney murine leukemia virus induces myeloid leukemia when inoculated intravenously into pristane-primed adult BALB/c mice. One hundred percent of these tumors show insertional activation of the c-myb proto-oncogene, and reverse transcriptase PCR assays have shown that the c-myb activation could be detected soon after infection. We tested BALB/c and NIH Swiss mice that had been inoculated as newborns with Moloney murine leukemia virus, under which conditions they develop T lymphomas exclusively. Reverse transcriptase-PCR assays indicated that c-myb activations were detectable soon after neonatal infection. However, none of the resulting T lymphomas contained c-myb activations. The implications of these results to the timing of proto-oncogene activations in leukemogenesis and the specificity of proto-oncogene activations for different diseases are discussed.

Novel integration sites at the distal 3' end of the c-myb locus in retrovirus-induced promonocytic leukemias

In BALB/c nu/nu and sublethally irradiated DBA/2 mice, promonocytic leukemia was induced by intravenous inoculation of Friend murine leukemia virus (F-MuLV) strain C57 in conjunction with intraperitoneal injection of pristane. These tumors appear to be identical morphologically to previously reported ones induced by other MuLVs, such as Moloney, amphotropic 4070A, and F-MuLV FB29, which most commonly have provirus integrations in the 5' end of the c-myb locus. Interestingly, 2 of the 16 F-MuLV-induced tumors had viruses integrated in the distal 3' end of c-myb. To determine the precise locations of these integrations, it was necessary to clone sequences encoding the 3' c-myb exons and to prepare a physical map of this region. Exons 10 to 15 were positioned on the map, and it was found that the proviruses in the aforementioned tumors were located within narrow region in the beginning of the large (greater than 11 kb) intron 14. The predicted protein product encoded by the affected alleles is truncated by 38 amino acids. This represents a novel virus integration site which is most likely associated with oncogenic activation of the c-myb gene during leukemogenesis.

Susceptibility and resistance to Moloney murine leukemia virus-induced promonocytic leukemia

Moloney murine leukemia virus (M-MuLV) induces promonocytic leukemias, called MML, in pristane-treated adult mice. These tumors invariably express fused gag-myb mRNA as a consequence of virus integration and activation of the c-myb locus. In the present study it was determined that while BALB/c and DBA/2N mice are highly susceptible, C57BL/6, C3H/He, STS/A, NFS, NIH/Swiss, SJL/J, and NZB mice are strongly resistant to tumor induction. Although C57BL/6 mice were resistant because they were unable to support early virus replication in hematopoietic tissue, NFS and C3H/He mice supported replication and were shown, using RT-PCR, to have cells in the bone marrow and spleen that expressed the aberrant, leukemia-related gag-myb mRNA. This provided evidence that early stages of leukemia were permitted to develop in these mice, but preneoplastic cells were unable to progress to the acute phase. Experiments in which MML was induced by M-MuLV plus pristane treatment in immunodeficient C3H/He nu/nu and sublethally irradiated C3H/He mice suggested that the immune response may play a role in eliminating preleukemic cells in immunocompetent C3H/He. Tumors from these mice had rearrangements at the c-myb locus and expressed gag-myb RNA. It was concluded that, at least in the case of C3H/He mice, resistance is not due to an inability of virus to activate c-myb or to a lack of other tumor promoting events. Rather, leukemia development appears to be restricted by an immune response, presumably T-cell mediated. Evidence is provided that non-H-2 MHC genes are required for resistance in both C57BL/6 and C3H/He mice and that resistance is dominant. This provides an animal model for the study of tumor progression as it relates to the immune response.

Different abilities of Friend murine leukemia virus (MuLV) and Moloney MuLV to induce promonocytic leukemia are due to determinants in both psi-gag-PR and env regions

Moloney murine leukemia virus (M-MuLV) is capable of inducing promonocytic leukemia in 50% of adult BALB/c mice that have received peritoneal injections of pristane, but Friend MuLV strain 57 (F-MuLV) is nonleukemogenic under similar conditions. It was shown earlier that these differences could not be mapped to the U3 region of the virus long terminal repeat, indicating the probable influence of structural genes and/or R-U5 sequences. In this study, reciprocal chimeras containing exchanged structural genes and R-U5 sequences from these two closely related viruses were analyzed for differences in ability to induce disease. Results showed that two regions of F-MuLV, psi-gag-PR and env, when substituted for those of M-MuLV were dramatically disease attenuating. The 5'-most region, which is widely distributed, overlaps with the 5' end of the env intron and includes the RNA packaging region, psi, the entire gag coding region, and the viral protease coding region (PR) of pol. It was also found that reciprocal constructs having substitutions of both of these regions of M-MuLV in an F-MuLV background allowed full reestablishment of promonocytic leukemia. These leukemias were positive for c-myb rearrangements which are characteristic of M-MuLV-induced promonocytic leukemias. Neither region alone, however, was sufficient to produce disease with a greater incidence than 13%. Further studies demonstrated that the inability of viruses with psi, gag, PR, or env sequences from F-MuLV to induce leukemia in this model system was not due to their inability to replicate in hematopoietic tissue, to integrate into the c-myb locus early on after infection in vivo, or to express gag-myb mRNA characteristic of M-MuLV-induced preleukemic cells and acute leukemia.