Gene expression in the female tree swallow brain is associated with inter- and intra-population variation in glucocorticoid levels

Studies of the evolutionary causes and consequences of variation in circulating glucocorticoids (GCs) have begun to reveal how they are shaped by selection. Yet the extent to which variation in circulating hormones reflects variation in other important regulators of the hypothalamic-pituitary-adrenal (HPA) axis, and whether these relationships vary among populations inhabiting different environments, remain poorly studied. Here, we compare gene expression in the brain of female tree swallows (Tachycineta bicolor) from populations that breed in environments that differ in their unpredictability. We find evidence of inter-population variation in the expression of glucocorticoid and mineralocorticoid receptors in the hypothalamus, with the highest gene expression in a population from an extreme environment, and lower expression in a population from a more consistent environment as well as in birds breeding at an environmentally variable high-altitude site that are part of a population that inhabits a mixture of high and low altitude habitats. Within some populations, variation in circulating GCs predicted differences in gene expression, particularly in the hypothalamus. However, some patterns were present in all populations, whereas others were not. These results are consistent with the idea that some combination of local adaptation and phenotypic plasticity may modify components of the HPA axis affecting stress resilience. Our results also underscore that a comprehensive understanding of the function and evolution of the stress response cannot be gained from measuring circulating hormones alone, and that future studies that apply a more explicitly evolutionary approach to important regulatory traits are likely to provide significant insights.

POS0244 ASSOCIATION OF PROTEINASE 3 GENE (PRTN3) Val119Ile POLYMORPHISM (SNP rs351111) WITH RISK OF RELAPSE AMONG HOMOZYGOUS PATIENTS WITH PR3 ANCA-ASSOCIATED VASCULITIS

Background

The frequency of the proteinase 3 gene (PRTN3) polymorphisms in patients with ANCA-associated vasculitis (AAV) is not well characterized. We hypothesize that PRTN3 gene polymorphisms induce allosteric changes in PR3 conformation which may alter its interaction with ligands and PR3-ANCA during inflammation with potential implications for disease presentation and clinical outcomes.

Objectives

To analyze the association of PRTN3 Val119Ile polymorphism (SNP rs351111) with risk of relapse risk among homozygous patients with PR3 ANCA-associated vasculitis.

Methods

DNA variant calling for SNP rs351111 (chr.19:844020, c.355G>A) in PRTN3 gene assessed the allelic frequency in patients with PR3-AAV included in the Rituximab versus Cyclophosphamide (RAVE) trial. This was followed by RNA-seq variant calling to characterize the mRNA expression. We compared clinical presentation and outcomes between patients homozygous for PR3-Ile119 or PR3-Val119.

Results

Serum samples for DNA calling were available in 188 of the 197 patients with AAV in the RAVE cohort. 75 PR3-AAV patients had the allelic variant: 13 patients were homozygous for PR3-Ile119 and 62 patients were heterozygous PR3-Val119Ile with an allele frequency threshold of 29.3 – 55.1% of reads (Figure 1A and 1B). RNA-seq was available for 89 patients and the mRNA corresponding to the allelic variant was found in 35 PR3-AAV patients: 13 patients were homozygous for PR3-Ile119 and 22 patients were heterozygous PR3-Val119Ile with an allele frequency threshold of 11.1 – 62.8% of reads (Figure 1A and 1C). The agreement between the DNA calling results and the mRNA expression of the 86 patients that overlapped was 100%. We found an additional homozygous patient for PR3-Val119 in which blood was not available for DNA calling. We compared the clinical presentation and outcomes of 74 patients with PR3-AAV: 13 homozygous for PR3-Ile119 and 51 homozygous for PR3-Val119 (Table 1). The frequency of severe flares at 18 months in homozygous PR3-Ile119 was ≥ 2x higher when compared with homozygous PR3-Val119 (46.2% vs. 19.6%, p=0.048). We found no differences in clinical presentation.

Figure 1.

RAVE trial population distribution according to the zygosity status for PRTN3 gene (PR3 and MPO-ANCA patients) and DNA or RNA variant calling (panel A). Allelic frequency for rs351111, chr.19:844020 (c.355G>A) in PRTN3 among patients with AAV (PR3 and MPO-ANCA) in the DNA (panel B) and RNA (panel C) variant calling.

Table 1.

Outcomes of patients with PR3-ANCA according with PRTN3 zygosity.

PR3-ANCA (n=64)Homozygous PR3-Val119(n=51)HomozygousPR3-Ile119(n=13)p-value Remission, n (%)45 (88.2)13 (100)0.194 Complete remission, n (%)36 (70.6)10 (76.9)0.650 Any flare 18 months, n (%)30 (58.8)7 (53.8)0.746 Severe Relapse* 18 months, n (%)10 (19.6)6 (46.2)0.048

* Relapse was considered “Severe” if Birmingham Vasculitis Activity Score for Wegener’s Granulomatosis (BVAS/WG) > 3 or one major item as per the RAVE trial definition.

Abbreviations: ANCA - anti-neutrophil cytoplasmic antibody; Ile – isoleucine; n- number; PR3 - proteinase 3; Val - valine.

Conclusion

In patients with PR3-AAV the presence of PRTN3 Val119Ile polymorphism was associated with higher frequency of severe relapse. Further studies are necessary to understand the association of this observation with the risk of severe relapse.

References

[1]Stone JH et al N Engl J Med 2010; 363:221-232

Disclosure of Interests

None declared

Ultraviolet irradiation increases size of the first clutch but decreases longevity in a marine copepod

An important component of life history theory is understanding how natural variation arises in populations. Both endogenous and exogenous factors contribute to organism survival and reproduction, and therefore, it is important to understand how such factors are both beneficial and detrimental to population dynamics. One ecologically relevant factor that influences the life history of aquatic organisms is ultraviolet (UV) radiation. While the majority of research has focused on the potentially detrimental effects that UV radiation has on aquatic organisms, few studies have evaluated hormetic responses stimulated by radiation under select conditions. The goal of this study was to evaluate the impact of UV-A/B irradiation on life history characteristics in Tigriopus californicus copepods. After exposing copepods to UV-A/B irradiation (control, 1-, and 3-hr UV treatments at 0.5 W/m2), we measured the impact of exposure on fecundity, reproductive effort, and longevity. We found that UV irradiation increased the size of the first clutch among all reproducing females in both the 1- and 3-hr experimental groups and decreased longevity among all females that mated in the 1-hr treatment. UV irradiation had no effect on the number of clutches females produced. These findings indicate a potential benefit of UV irradiation on reproductive performance early in life, although the same exposure came at a cost to longevity.

Change in the Lipid Transport Capacity of the Liver and Blood during Reproduction in Rats

To support the high energetic demands of reproduction, female mammals display plasticity in many physiological processes, such as the lipid transport system. Lipids support the energy demands of females during reproduction, and energy and structural demands of the developing offspring via the placenta in utero or milk during the suckling period. We hypothesized that key proteins supporting lipid transport in reproductive females will increase during pregnancy and lactation, but drop to non-reproductive levels shortly after reproduction has ended. We compared the relative protein levels of liver-type cytosolic fatty acid transporter (L-FABP_c), plasma membrane fatty acid transporter (FABPpm), fatty acid translocase (FAT/CD36) in the liver, a key site of lipid storage and synthesis, and free fatty acid transporter albumin and triglyceride transporter [represented by apolipoprotein B (apoB)] levels in serum in reproductive Sprague-Dawley rats during late pregnancy, peak-lactation, and 1-week post-lactation as well as in non-reproductive rats. We found that all lipid transporter levels were greater in pregnant rats compared to non-reproductive rats. Lactating rats also showed higher levels of FAT/CD36 and FABPpm than non-reproductive rats. Moreover, all fat transporters also dropped back to non-reproductive levels during post-lactation except for FAT/CD36. These results indicate that fat uptake and transport capacities in liver cells are elevated during late gestation and lactation. Liver lipid secretion is up-regulated during gestation but not during lactation. These data supported the plasticity of lipid transport capacities in liver and blood during reproductive stages.

[Occupational Health Physicians and Rehabilitation - A Cross-sectional Study on Occupational Health Care in Schleswig-Holstein and Baden-Württemberg]

Objective Description and explanation of involvement of occupational health physicians in rehabilitation Methods Data were collected by a survey of occupational health physicians in Schleswig-Holstein and Baden-Württemberg. Logistic regression models were calculated to identify determinants of the involvement of occupational health physicians before, during and after rehabilitation. Results During the last year 70% of the occupational health physicians have supported at least one worker when applying for medical rehabilitation. About a half has had at least once contact to a rehabilitation facility during the rehabilitation treatment of an employee, and 9 out of 10 physicians have supported at least one employee after her or his rehabilitation when returning to work. Support by occupational health physicians is more likely when they feel responsible for rehabilitation, are well informed and frequently involved in occupational reintegration management. Conclusions Occupational health physicians may be important stakeholders for preparing and supporting rehabilitation.

European Attempts to Set Guidelines for Improving Diagnostics of Autoimmune Rheumatic Disorders

The rational way to set a diagnosis and estimate a prognosis in rheumatology is to start by setting a tentative diagnosis and then follow a fixed scheme for laboratory testing, eg, by using an agreed algorithm. The use of order algorithms can be extended to post-test algorithms that will assist clinicians in approaching the right diagnosis and prognosis. New methods used in autoimmune serology do not deliver results that can be directly compared to those of older methods, and thus the new methods need to be thoroughly tested with sera from differential diagnostically relevant disease controls to set a clinically meaningful cut-off for positivity. Borderline positive results need to be treated with special care to avoid misuse. Early diagnosis is of great importance, and serological results can be very useful if used the right way. European efforts to secure rational diagnostic work-up in autoimmune rheumatic disease have led to a better dialogue between clinicians and laboratory scientists in several countries.

EULAR recommendations for the management of systemic lupus erythematosus with neuropsychiatric manifestations: report of a task force of the EULAR standing committee for clinical affairs

OBJECTIVES

To develop recommendations for the diagnosis, prevention and treatment of neuropsychiatric systemic lupus erythematosus (NPSLE) manifestations.

METHODS

The authors compiled questions on prevalence and risk factors, diagnosis and monitoring, therapy and prognosis of NPSLE. A systematic literature search was performed and evidence was categorised based on sample size and study design.

RESULTS

Systemic lupus erythematosus (SLE) patients are at increased risk of several neuropsychiatric manifestations. Common (cumulative incidence > 5%) manifestations include cerebrovascular disease (CVD) and seizures; relatively uncommon (1-5%) are severe cognitive dysfunction, major depression, acute confusional state (ACS), peripheral nervous disorders psychosis. Strong risk factors (at least fivefold increased risk) are previous or concurrent severe NPSLE (for cognitive dysfunction, seizures) and antiphospholipid antibodies (for CVD, seizures, chorea). The diagnostic work-up of suspected NPSLE is comparable to that in patients without SLE who present with the same manifestations, and aims to exclude causes unrelated to SLE. Investigations include cerebrospinal fluid analysis (to exclude central nervous system infection), EEG (to diagnose seizure disorder), neuropsychological tests (to assess cognitive dysfunction), nerve conduction studies (for peripheral neuropathy) and MRI (T1/T2, fluid-attenuating inversion recovery, diffusion-weighted imaging, enhanced T1 sequence). Glucocorticoids and immunosuppressive therapy are indicated when NPSLE is thought to reflect an inflammatory process (optic neuritis, transverse myelitis, peripheral neuropathy, refractory seizures, psychosis, ACS) and in the presence of generalised lupus activity. Antiplatelet/anticoagulation therapy is indicated when manifestations are related to antiphospholipid antibodies, particularly thrombotic CVD.

CONCLUSIONS

Neuropsychiatric manifestations in SLE patients should be first evaluated and treated as in patients without SLE, and secondarily attributed to SLE and treated accordingly.

Disease spectrum of patients with antineutrophil cytoplasmic autoantibodies of defined specificity: distinct differences between patients with anti-proteinase 3 and anti-myeloperoxidase autoantibodies

OBJECTIVE

To compare the disease spectrum of consecutive patients with antineutrophil cytoplasmic autoantibodies directed against proteinase 3 (anti-PR3) or myeloperoxidase (anti-MPO).

DESIGN

Retrospective analysis.

SETTING

Three teaching hospitals in the Netherlands.

MAIN OUTCOME MEASURES

Clinical features at presentation, histopathological characteristics and outcome.

SUBJECTS

All consecutive patients who tested positive for anti-PR3 (n=46) or anti-MPO (n=46) over an 8-year-period.

RESULTS

At diagnosis, patients with anti-PR3 had a higher vasculitis activity index than patients with anti-MPO (P < 0.001). The mean (SD) number of affected organs in the anti-PR3 group exceeded that of the anti-MPO group (3.9 (1.4) and 2.2 (1.1), respectively; P < 0.01). The combination of renal and respiratory tract involvement was present in as many as 78.3% of patients with anti-PR3 and in only 23.9% of patients with anti-MPO (P < 0.01). Renal-limited disease exclusively occurred in patients with anti-MPO. Granulomas were found in 41.3% of anti-PR3- but in only 4.3% of anti-MPO-positive patients (P < 0.01). All anti-PR3-positive patients had Wegener's granulomatosis or microscopic polyangiitis. By contrast, diagnoses in the anti-MPO group were more diverse: idiopathic necrotizing crescentic glomerulonephritis (26.1%), microscopic polyangiitis (26.1%). Churg-Strauss syndrome (4.3%), Wegener's granulomatosis (2.2%), giant cell arteritis (2.2%), clinically suspected vasculitis (19.6%), as well as miscellaneous nonvasculitic disorders (19.6%). During follow-up, 10 anti-PR3-positive patients had 11 relapses whereas only 3 patients with anti-MPO relapsed (P=0.04).

CONCLUSION

A large divergence was seen in the disease spectrum between patients with anti-PR3 and those with anti-MPO. In particular, extra-renal disease manifestations, granuloma formation and relapses were more prominent in anti-PR3- than in anti-MPO-positive patients.

Antineutrophil cytoplasmic antibodies in juvenile chronic arthritis

OBJECTIVE

To evaluate the diagnostic significance of antineutrophil cytoplasmic antibodies (ANCA) by assessing the prevalence of ANCA in juvenile chronic arthritis (JCA) (n = 93) of either oligoarticular, polyarticular, or systemic onset. To investigate the prevalence of ANCA in other diseases of childhood characterized by chronic inflammation (n = 44), such as cystic fibrosis, juvenile diabetes mellitus, and connective tissue diseases.

METHODS

Indirect immunofluorescence on both ethanol and paraformaldehyde fixed neutrophils, ELISA for specific antigens, Western blotting using sonicated neutrophils.

RESULTS

ANCA were detected in the sera from 35% of patients with JCA, and in only 7% of patients with other inflammatory diseases. Regarding the onset type of JCA, ANCA were present in 44% of patients with oligoarticular onset, in 36% with polyarticular onset, and in 16% with systemic onset. All but one ANCA positive serum sample produced a perinuclear fluorescence pattern on ethanol fixed granulocytes. However, on neutrophils fixed with paraformaldehyde either a cytoplasmic (14%) or a nuclear (23%) staining pattern was observed, suggesting that both cytoplasmic and nuclear autoantibodies occur in JCA. Further characterization studies showed that ANCA in JCA are not directed against proteinase 3, elastase, or myeloperoxidase. On Western blots ANCA in JCA incidentally showed reactivity with either lactoferrin (5%) or 2 polypeptides of 66/67 kDa (9%).

CONCLUSION

Prevalence and antigenic specificity of ANCA in JCA are clearly different from adult onset rheumatoid arthritis or other juvenile chronic inflammatory disorders.

Prevention of relapses in systemic lupus erythematosus

Many relapses of systemic lupus erythematosus (SLE) are preceded by a rise in antibodies against double-stranded DNA (anti-dsDNA). We investigated whether these relapses can be prevented by giving prednisone when a rise in anti-dsDNA occurs. 156 patients with SLE were studied. Anti-dsDNA was measured by Farr assay monthly. When a rise in anti-dsDNA was found, patients were randomly assigned either conventional treatment or 30 mg prednisone added to the current daily dose and tapering off to baseline over 18 weeks. A rise in anti-dsDNA was detected in 46 patients (24 assigned conventional treatment and 22 prednisolone). The relapse rate was higher in the conventional group than in the prednisolone group (20 vs 2, p < 0.001). Although rises in anti-dsDNA in the prednisone group were treated with additional prednisone, the cumulative oral doses of prednisone in the two groups did not differ significantly (p = 0.025). 7 major relapses requiring additional cytotoxic immunosuppressive treatment occurred in the conventional group versus 2 in the prednisone group. Treatment with prednisone as soon as a significant rise in anti-dsDNA occurs prevents relapse in most cases, without increasing the cumulative dose of prednisdone given.

Neurologic manifestations of systemic vasculitides

Involvement of the nervous system is frequently observed in patients with vasculitis. Peripheral neuropathy is often an early and dominating feature of the disease process. Cranial nerve palsy, central nervous system vasculitis, and inflammatory myopathy are other neurologic manifestations.

Occurrence of autoantibodies to human leucocyte elastase in Wegener's granulomatosis and other inflammatory disorders

Antineutrophil cytoplasmic antibodies (ANCAs) constitute a new class of autoantibodies that seem to recognise myeloid lysosomal enzymes. The occurrence of ANCAs with specificity for human leucocyte elastase (HLE) was assessed in serum samples that were routinely submitted for ANCA determination. During a study period of more than six years anti-HLE was found in only six out of 1102 serum samples that produced a perinuclear or an atypical cytoplasmic staining pattern on ethanol fixed granulocytes. These six serum samples were from four patients with a clinical diagnosis of Wegener's granulomatosis but without a definite histological diagnosis, one patient with systemic vasculitis, and one patient with Cogan's syndrome. To further evaluate the prevalence of anti-HLE we tested 315 serum samples from patients with different forms of vasculitis and related disorders. Anti-HLE was detected in two patients only. Thus autoantibodies to HLE are rarely found in serum samples from patients with vasculitic or related disorders.

Suppression of DNA synthesis by Con A-activated human lymphocytes: Stimulation by con A bound to non-T cells unless removed after activation

The capacity of human peripheral blood lymphocytes to suppress DNA synthesis of other lymphocytes was studied in an assay consisting of two steps: firstly, activation by Con A during 24 hr followed by alpha-methylglucoside and mitomycin treatment; secondly, incubation of these Con A-activated 'suppressor' cells with autologous responder cells and stimulants, or incubation with allogeneic responder cells. The results were compared with cells similarly treated but not incubated with Con A. If alpha-methylglucoside treatment is omitted, stimulation of T and non-T cells occurs by Con A bound to the Con A-activated cells. Con A is especially bound to non-T lymphocytes and even gives a T cell-independent proliferation of non-T cells without differentiation to plasma cells. With alpha-methylglucoside treatment, 'suppressor' cells, activated by high Con A concentrations, are able to suppress DNA synthesis of autologous lymphocytes stimulated by allogeneic cells or soluble antigens to about 50%. In a one-way MLC, in which the cell suspension containing the suppressor cells is also used as a stimulator cell suspension, a similar suppression was observed. Suppression of DNA synthesis was correlated with suppression of proliferation without evidence of cytotoxicity.