Successful long-term systemic sclerosis treatment by high-frequent low-dose B cell-depleting therapy

OBJECTIVES

Systemic sclerosis (SSc) is a multiorgan disease with a 10-year mortality rate of up to 50 %. B cell-depleting therapy with rituximab (RTX) appears effective in SSc treatment, but data from randomized controlled trials (RCTs) are lacking, and the frequency and dosage of RTX in SSc have no consensus. We aimed to evaluate the long-term efficacy and safety of quarterly RTX administration in SSc.

METHODS

This study retrospectively analyzed 40 patients with SSC treated with RTX twice within 14 days every 3 months from 2010 to 2020. The patients fulfilled the LeRoy and the American College of Rheumatology/European League Against Rheumatism Criteria for SSc. Modified Rodnan skin score (mRSS), lung function test results, and serum immunoglobulin (IgG, IgA, and IgM) concentrations were analyzed.

RESULTS

A total of 40 patients with SSc received RTX over a median time of 3.9 years (range: 1-10 years). The median mRSS (baseline: 19, 24 months: 16, p < 0.001) demonstrated a significant improvement, and the predicted forced vital capacity was stable. No new or unexpected safety signals, especially regarding treatment-related infectious adverse events, were observed. Immunoglobulin concentrations were within normal range, and specific antibodies to pneumococcal polysaccharides were preserved despite long-term B cell-depleting therapy. None of the patients died during the observation period of up to 10 years.

CONCLUSION

SSc was effectively and safely treated with low-dose RTX quarterly. RCTs are warranted to validate the advantage of continuous B cell depletion by quarterly low-dose RTX administration compared to other treatment intervals.

POS1390 ULTRASOUND BASED WITHDRAWAL OF BIOLOGICS IN RHEUMATOID ARTHRITIS (RA-BioStop)

Background

Discontinuation of biological (b)DMARDs may be considered in rheumatoid arthritis (RA) patients in persistent clinical remission [1]. Some earlier studies reported that baseline ultrasound may predict successful tapering or withdrawal of bDMARDs, while others found that ultrasound had little additional value over clinical parameters alone [2-4]. The majority of these studies, however, were limited by small sample size, inadequate remission criteria and variable tapering regimens.

Objectives

To test the hypothesis whether ultrasound-verified subclinical inflammation might predict a relapse in RA patients in stringent clinical remission who discontinue bDMARDs.

Methods

Prospective, phase IV clinical trial including RA patients in persistent clinical remission according to the ACR/EULAR criteria treated with a combination of conventional synthetic (cs)DMARD plus bDMARDs. Upon stopping the bDMARD, 9 study visits were conducted within 52 weeks. At each visit, patients underwent clinical examination and ultrasound of 14 joints. The primary hypothesis was that a Power Doppler (PD) score >0 predicted a relapse until week 16 after bDMARD cessation. Relapse was defined as change from remission to moderate/high disease activity according to the simplified disease activity index.

Results

Although 110 patients were required by the protocol, inclusion had to be stopped after reaching 38 (34.5%) due to insufficient recruitment. There were 9, 10 and 13 relapses between baseline and weeks 16, 24 and 52, respectively. Relapses till week 16 tended to be more common in patients with PD score >0 at baseline than in those without [9/30 (30.0%) vs. 0/7 (0%), p=0.160)]. Similar observations were made for weeks 24 [9/30 (30.0%) vs. 1/7 (14.3%), p=0.647)] and 52 [12/30 (40.0%) vs. 1/7 (14.3%), p=0.383)]. Kaplan-Meier plot indicates the relapse-free survival in patients with and without PD+ synovitis at baseline (Figure 1).

Figure 1.

Kaplan-Meier analysis of relapses according to presence or absence of Power Doppler (PD) synovitis at baseline.

PD scores were higher at the time of relapse as compared to the preceding visits [mean difference in the PD score 3.2 (±4.5) points, p=0.034]. PD scores were also higher at visits preceding a relapse [mean 5.6 (±3.9), n=13] as compared to the mean PD score across all visits of patients without a relapse [mean 2.0 (±1.5), n=24, p=0.003, respectively]. There were trends towards a higher mean baseline PD score in patients who had a relapse between baseline and week 16 as compared to those who remained in remission (5.2 ± 5.8 vs. 2.3 ± 3.0, p=0.079). Similar observations were made for relapses until weeks 24 and 52. No difference was observed comparing mean residual swollen or tender joint counts at baseline between patients with and without a relapse. There were 9 adverse events. All of them were mild to moderate.

Conclusion

In RA patients in strict clinical remission, PD assessment at baseline but not clinical joint count could help identify patients who will relapse after the cessation of a bDMARD. Due to insufficient recruitment and limited power of the present trial, however, no definitive conclusion can be made.

References

[1]Smolen JS, Landewé RBM, Bijlsma JWJ, et al. EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs: 2019 update. Ann Rheum Dis 2020;79:685-99.

[2]Naredo E, Valor L, De la Torre I, et al. Predictive value of Doppler ultrasound-detected synovitis in relation to failed tapering of biologic therapy in patients with rheumatoid arthritis. Rheumatology (Oxford) 2015;54:1408–14.

[3]Lamers-Karnebeek FB, Luime JJ, Cate DFT, et al. Limited value for ultrasonography in predicting flare in rheumatoid arthritis patients with low disease activity stopping TNF inhibitors. Rheumatology (Oxford) 2017;56:1560–5.

[4]Terslev L, Brahe CH, Hetland ML, et al. Doppler ultrasound predicts successful discontinuation of biological DMARDs in rheumatoid arthritis patients in clinical remission. Rheumatology (Oxford) 2021;60:5549–59.

Acknowledgements

This study was funded by a grant of the Austrian Research Fund (KLI514-B30)

Disclosure of Interests

Christian Dejaco Speakers bureau: Pfizer, AbbVie, MSD, Roche, BMS, UCB, Consultant of: Pfizer, AbbVie, MSD, Roche, BMS, UCB, Grant/research support from: Pfizer, Irina Gessl: None declared, Rusmir Husic Speakers bureau: MSD, Lilly und Abbvie, Thomas Deimel: None declared, Angelika Lackner: None declared, Gabriela Supp: None declared, Josef Hermann Speakers bureau: Novartis, Lilly, AbbVie, Janssen, Consultant of: GlaxoSmithKline, Otsuka Pharmaceutical Europe Ltd, Josef S. Smolen Speakers bureau: AbbVie, Amgen, AstraZeneca, Astro, Bristol-Myers Squibb, Celgene, Celltrion, Chugai, Gilead, ILTOO, Janssen, Lilly, Merck Sharp & Dohme, Novartis- Sandoz, Pfizer, Roche, Samsung, Sanofi, and UCB, Consultant of: AbbVie, Amgen, AstraZeneca, Astro, Bristol-Myers Squibb, Celgene, Celltrion, Chugai, Gilead, ILTOO, Janssen, Lilly, Merck Sharp & Dohme, Novartis- Sandoz, Pfizer, Roche, Samsung, Sanofi, and UCB, Grant/research support from: Abbvie, AstraZeneca, Lilly and Roche, Martin Stradner Speakers bureau: Eli Lilly, Pfizer, MSD, BMS, AbbVie, Janssen, Consultant of: Eli Lilly, AbbVie, Janssen, Daniel Aletaha Speakers bureau: Abbvie, Amgen, Lilly, Janssen, Merck, Novartis, Pfizer, Roche, Sandoz, Consultant of: Abbvie, Amgen, Lilly, Janssen, Merck, Novartis, Pfizer, Roche, Sandoz, Grant/research support from: Abbvie, Amgen, Lilly, Novartis, Roche, SoBi, Sanofi, Gerold Schwantzer: None declared, Peter Mandl Speakers bureau: AbbVie, Janssen and Novartis, Grant/research support from: AbbVie, BMS, Novartis, Janssen, MSD and UCB

POS0408 TRANSFER OF HUMAN RHEUMATOID ARTHRITIS MONONUCLEAR CELLS INDUCES ARTHRITIS IN IMMUNODEFICIENT HLA-DR4 TRANSGENIC MICE

Background

Rheumatoid arthritis (RA) is a systemic autoimmune disease leading to erosive joint destruction. Although the exact pathogenesis is still elusive, the strong association of certain HLA class II molecules, such as HLA-DRB1*0401 (HLA-DR4), suggest involvement of CD4+ T cells (1,2). Mouse models of RA mimic specific aspects of the disease but are limited by the differences between human and murine immune systems.

Objectives

We aimed to establish a humanized mouse model (humice) carrying DR4+ RA PBMCs to study its role in the pathogenesis of RA without putting patients at risk.

Methods

Peripheral blood mononuclear cells (PBMC) of HLA-DR4 positive RA patients or controls were isolated and injected into NSG-Ab0 DR4 mice (NOD-scid IL2Rgammanull mice lacking MHC class II while expressing the human HLA-DR4) to create humice. Human immune cell composition within humice was profiled using flow cytometry. Development of RA was monitored by examination of the joints and micro computed tomography analysis. Joints were analysed by histology regarding pannus formation, bone erosions, cartilage damage, and human cell infiltration.

Results

Transfer of RA PBMCs induced arthritis in humice recapitulating hallmarks of RA including immune cell infiltration, pannus formation, increased osteoclastogenesis, cartilage damage, and bone erosions. Arthritis was dependent on the implanted human cells as NSG-Ab0 DR4 mice without transfer of human PBMCs did not develop arthritis. T-helper 1 (Th1) cells, dominated the human immune cell composition in humice, while regulatory T cells (Tregs) were diminished compared to donor PBMC composition. Mice humanized with cells from RA patients were more likely to develop inflammatory joint disease, compared to healthy HLA-DR4 positive controls (RA donor 70% vs. healthy control 20%, p=0.00196). CTLA-4 Ig treatment prevented arthritis development in this model (p=0.0055).

Conclusion

Humice carrying DR4+ RA PBMCs developed an RA-like erosive joint disease driven by the implanted human immune system. The data implies that the disease can be transferred by arthritogenic cells found in the peripheral blood of RA patients. This model will allow new insights into the pathogenesis of RA.

References

[1]Goulielmos GN, Zervou MI, Myrthianou E, Burska A, Niewold TB, Ponchel F. Genetic data: The new challenge of personalized medicine, insights for rheumatoid arthritis patients. Gene Available from: http://www.ncbi.nlm.nih.gov/pubmed/26869316

[2]Holoshitz J. The rheumatoid arthritis HLA–DRB1 shared epitope. Curr Opin Rheumatol Available from: http://www.ncbi.nlm.nih.gov/pubmed/20061955

Disclosure of Interests

None declared.

AB0472 DEFINING AN ACCEPTABLE STATE OF QUALITY OF LIFE IN PRIMARY SJÖGREN’S SYNDROME

Background

The PSS-QoL (the Primary Sjögren’s Syndrome Quality of Life Questionnaire) is a disease-specific health-related quality of life (HRQL) questionnaire in primary Sjögren Syndrome (PSS). The psychometric testing showed a valid and reliable assessment, which allows a comprehensive evaluation of the patients’ perspective and the extent of the disease in PSS.

Objectives

To define the threshold of an acceptable QoL state (AQLS) and the minimal detectable change (MDC) of the PSS-QoL.

Methods

Data of patients from the PSS registry of the Medical University of Graz fulfilling the 2016 ACR/EULAR classification criteria for PSS were analysed. Patients completed the PSS-Qol and ESSPRI (EULAR Sjögren’s syndrome patient-reported index), disease activity was assessed by the ESSDAI (EULAR Sjögren’s syndrome disease activity index) and an evaluator’s global assessment (EGA, scale from 0 to 10). Receiver operating characteristic curve analyses were used to estimate the AQLS based on patients’ assessment on the extent of HRQL. We selected the optimal cut-off of PSS-QoL by the maximal Youden index. At the follow – up visits after 12 months, patients assessed, whether their HRQL had changed. An anchoring method based on this evaluation was used to estimate the MDC of PSS-QoL. Furthermore, clinical data were compared in AQLS and non-AQLS groups.

Results

Data from 152 PSS patients were analysed which of 91.4% (n=139) were female. The mean age was 59.65±12.3 years (± standard deviation) and the mean disease duration was 5.6±5.3 years.

The AQLS estimate was defined as PSS-QoL≤29.5. 40.1% (n=61) were categorized to be in AQLS. Although AQLS patients were significantly younger (56.9±13.1years vs 61.5±11.4 years, p<0.01) they had a longer disease duration (6.9±5.8 years vs. 4.7±4.7 years, p<0.05) compared to non-AQLS patients. AQLS patients had a lower EGA (2 [0-5] vs 3 [0-7], p<0.01 (median [range]), higher IgG (15.7[7.7-33.8, range] vs 13.1 [6.5-38.1], p<0.05) and higher rheumatoid-factor IgA (84 [0-500] vs 20 [0-500], p<0.01).

AQLS patients showed significantly lower burden of sicca (measured by ESSPRI and sicca VAS scores).

The MDC for PSS-QoL was defined as 12.2 points. After one year, patients’ HRQL did not change in 83.3% and got worse 7.1%.

Conclusion

This study determined the AQLS and the minimal detectable change for HRQL. These results will help evaluating the HRQL of patients in clinical practice, as well as possible assistance designing future clinical trials. Patients in AQLS show lower dryness scores but higher immunological activity compared to non-AQLS patients. Longitudinal studies are needed to determine factors affecting patients’ HRQL in PSS.

Disclosure of Interests

None declared

POS1063 STAT PHOSPHORYLATION AS A MARKER FOR DISEASE ACTIVITY IN PATIENTS WITH PSORIATIC ARTHRITIS: AN EXPLORATIVE ANALYSIS

Background

Numerous cytokines that influence disease activity in psoriatic arthritis (PsA) are modulators of the Janus Kinases/Signal Transducers and Activators of Transcription (JAK/STAT) pathway. The JAK1/STAT1/STAT3/STAT5 network can drive the expansion of Th17 and regulatory T cells via proinflammatory cytokines in PsA joints,[1], [2] while hyperphosphorylation of STAT3 in immune cells has previously been shown to promote PsA pathogenesis through the Interleukin (IL)-23/IL-17/IL-22 axis.[3] Therefore, the phosphorylation status of STAT molecules in leucocytes of PsA patients may indicate active disease and could potentially guide treatment with JAK inhibitors.

Objectives

To analyse phosphorylated STAT (pSTAT) levels of circulating leucocyte subsets in PsA patients with active and inactive disease

Methods

Whole blood was drawn on consecutive PsA patients fulfilling the CASPAR criteria[4] to perform flow cytometry analysis using the BD FACSLyric platform. Disease activity was assessed using the Disease activity for psoriasis arthritis (DAPSA) score.[5] All steps from storage of drawn blood to cell fixation were performed at 4°C to prevent auto-activation of leucocytes. The geometric mean fluorescence intensities (gMFI) of pSTATs in granulocytes, monocytes, B cells and CD4+/- naïve/memory T cells were compared between patients with moderate to high (MoDA/HDA) and remission to low disease activity (REM/LDA). Correlation analysis between gMFIs and DAPSA scores were performed.

Results

Forty-two patients (female ratio: 0.48) with established PsA (median ± standard deviation, age: 56 ± 12.54 years, disease duration: 8.50 ± 7.10 years) were included in this study. Twenty-one percent of patients were in MoDA/HDA, while the remaining 79% were in REM/LDA. Patients in MoDA/HDA showed significantly higher pSTAT3 levels in CD4+ naïve (gMFI median ± standard deviation: 284.5 ± 79.9 vs 238 ± 92.9, p = 0.011), CD4- naïve (297 ± 107.5 vs 238 ± 98.4, p = 0.04), CD4+ memory (227 ± 62.9 vs 190.5 ± 72.2, p = 0.009) and CD4- memory T cells (209 ± 66.8 vs 167.0 ± 64.9, p = 0.036). On the other hand, PsA patients in remission or low disease activity displayed higher pSTAT1 levels in granulocytes (2509 ± 1887 vs 1330.5 ± 784.1, p = 0.040) and monocytes (255 ± 230 vs 144 ± 62.5, p = 0.049). Positive correlations were found between DAPSA scores and pSTAT3 in CD4+ naïve and memory T cells (Spearman’s correlation coefficient rho (ρ) = 0.5, p = 0.0012 and ρ = 0.47, p = 0.0025 resp.) whereas pSTAT1 in granulocytes and monocytes were negatively correlated with the DAPSA scores (ρ = -0.45, p = 0.0074 and ρ = -0.34, p = 0.05).

Conclusion

Differential phosphorylation of STAT3 and STAT1 molecules in circulating leucocyte subsets indicates PsA disease activity. Further studies to examine the value of STAT phosphorylation patterns guiding JAK inhibitor therapy are underway.

References

[1]U. Fiocco et al., “Ex vivo signaling protein mapping in T lymphocytes in the psoriatic arthritis joints,” J. Rheumatol., vol. 93, pp. 48–52, 2015, doi: 10.3899/jrheum.150636.

[2]S. K. Raychaudhuri, C. Abria, and S. P. Raychaudhuri, “Regulatory role of the JAK STAT kinase signalling system on the IL-23/IL-17 cytokine axis in psoriatic arthritis,” Ann. Rheum. Dis., vol. 76, no. 10, pp. e36–e36, 2017.

[3]E. Calautti, L. Avalle, and V. Poli, “Psoriasis: A STAT3-centric view,” International Journal of Molecular Sciences, vol. 19, no. 1. MDPI AG, Jan. 06, 2018, doi: 10.3390/ijms19010171.

[4]W. Taylor, D. Gladman, P. Helliwell, A. Marchesoni, P. Mease, and H. Mielants, “Classification criteria for psoriatic arthritis: Development of new criteria from a large international study,” Arthritis Rheum., vol. 54, no. 8, pp. 2665–2673, 2006, doi: 10.1002/art.21972.

[5]M. M. Schoels, D. Aletaha, F. Alasti, and J. S. Smolen, “Disease activity in psoriatic arthritis (PsA): Defining remission and treatment success using the DAPSA score,” Ann. Rheum. Dis., vol. 75, no. 5, pp. 811–818, 2016, doi: 10.1136/annrheumdis-2015-207507.

Disclosure of Interests

Barbara Dreo: None declared, Daniel Ruben Pietsch: None declared, Rusmir Husic Speakers bureau: MSD, Lilly und Abbvie, Angelika Lackner: None declared, Johannes Fessler: None declared, Janine Rupp: None declared, Anirudh Subramanian Muralikrishnan: None declared, Jens Thiel Speakers bureau: GSK, BMS, AbbVie, Novartis, Consultant of: GSK, Novartis, Grant/research support from: BMS, Martin Stradner Speakers bureau: Eli Lilly, Pfizer, MSD, BMS, AbbVie, Janssen, Consultant of: Eli Lilly, AbbVie, Janssen, Philipp Bosch Grant/research support from: Pfizer

POS0917 TRANSTHORACIC LUNG SONOGRAPHY (LUS) – USEFUL SURVEILLANCE TOOL IN SYSTEMIC SCLEROSIS ASSOCIATED INTERSTITIAL LUNG DISEASE?

Background

The Interstitial lung disease (ILD) represent a major cause of mortality in Systemic sclerosis (SSc). Validated methods for screening and therapy monitoring of SSc-ILD are needed. In the recent literatur, the transthoracic lung sonography (LUS) emerges as a reliable tool for the early detection of lung alterations. It was recently reported that SSc-ILD-patients have thicker artefacts reflecting the pleuraline compared with SSc-patients without ILD, but it still remains unknown if the thickness of the pleuraline changes with a proper therapy response.

Objectives

The aim of the study was to compare the thickness of the pleuraline of SSc-ILD-patients without biological Disease Modifying Anti-Rheumatic Drugs (bDMARDS) with those successfully treated with bDMARDs in order to establish if LUS can be a reliable surveillance tool in SSc-ILD. Additionally, since our Grazer-Schema (Mycofenolat mofetil (MMF)+ rituximab (RTX) 500 mg i.v. in week 0 and 2 every 3 months) is succesfully used in our clinic since more than 10 years in patients nonresponding to methotrexate (MTX) or cyclophosphamide, we report 10 years follow-up data of 5 Patients before and after receiving that schema.

Methods

29 prospectively enrolled SSc-patients were assessed according to the European League Against Rheumatism Scleroderma Trial and Research standards. Written informed consent was obtained from all patients and the study was approved by the Ethics Committee of Graz. Validated clinical scores, such as the scleroderma disease activity (SScAS) and the scleroderma disease severity scale (SScSS) were assessed. The thickness of the pleuraline was detected with LUS. The presence of ILD was assessed by high-resolution computed tomography. Twenty-five SSc-patients enrolled between 2008 and 2009, who underwent LUS with the same technical instruments and some of the same operators, were taken as a control group since they were untreated yet or were not assuming bDMARDs(1).

Results

Of the 29 SSc-patients (27 females/2 males) enrolled between 2019 and 2020, seventeen patients had radiographic signs of ILD (SSc-ILD+/2019-20, n=17). Until the LUS was performed, all SSc-ILD+/2019-20 showed a good clinical response to the therapy with RTX in combination with MMF. Of the 25 SSc-patients enrolled in our previous study, (n=25; 23 females/ 2 males), twelve of these patients had radiographic signs of ILD (SScILD+/2009-10, n=12); 7 were under MTX or Cyclosporin and 5 were untreated. Additionally, data collected from 5 SSc-ILD+/2009-2010 at baseline were analysed in a 10- years- follow up. As expected, SSc-ILD+ patients had a thicker pleuraline than SSc-ILD- patients. The pleura was significantly thinner in patients under MMF und RTX compared to the pleuraline of patients without bDMARDs (1,8 mm ± 0,7 Vs 0,95 ± 0,31; p < 0,00). Interestingly those patients reported less frequently dry cough or dyspnoea, showing that the lower pleura thickness could be associated with a better clinical outcome. In a 10 Year follow-up after continued treatment with MMF and RTX, a significant reduction of the thickness of the pleura could be found (Mean 0,68 ± 0,2 VS 1,5 ± 0,4; p < 0,00). Interestingly, such significant improvement could be found in all of these 5 patients receiving our Grazer Schema. Remarkably, the pleuraline-thickness was comparable to the thickness of the pleura of SSc-ILD-patients. This finding shows that the increase in thickness of the pleuraline can be totally reversible under treatment.

Conclusion

Due to the encouraging validity, reliability and simplicity of LUS, it has been increasingly considered as an excellent screening tool for SSc-ILD. Its sensitivity to reveal parenchyma and pleura changes over time in treated patients, make it also a helpful and safe methodology to follow up SSc-ILD patients.

References

[1]Moazedi-Fuerst, F. C. et al. Pulmonary echography in systemic sclerosis. Clinical Rheumatology (2012) doi:10.1007/s10067-012-2055-8.

Disclosure of Interests

None declared

POS0786 IDENTIFYING INDIVIDUALS AT RISK FOR SJÖGREN’S SYNDROME – THE PRE-SJÖGREN SYNDROME TARGETED IMMUNOLOGY EVALUATION (PRESTIGE) STUDY

Background

Primary Sjögren’s Syndrome (pSS) is a chronic autoimmune disease. Symptoms range from sicca to systemic, potentially life-threatening organ damage. Little is known about the onset of the disease. Anti-Ro antibodies are described to develop years before the first symptoms. In addition, first degree relatives of pSS patients have an 11- to 19- fold increased risk of developing pSS themselves.

Objectives

To identify and follow-up individuals at risk for pSS in order to study symptoms and immune pathology before and at development of pSS.

Methods

In this ongoing long-term study individuals at risk for developing pSS but not fulfilling the ACR-EULAR classification criteria of pSS were included, defined as: 1.) Anti-SSA positive individuals (Anti-SSA+) without any sicca symptoms or diagnosis of an underlying systemic autoimmune disease; 2.) First degree relatives of patients (relatives) with an established diagnosis of pSS and typical autoantibodies (ANA ≥ 1:160 and/or anti-SSA+ and/or rheumatoid factor+); 3.) Individuals with at least one feature of the ACR-EULAR classification criteria for pSS, but not fulfilling the criteria (incomplete).

At baseline and at annual visits, demographic data, blood, saliva and urine samples were collected and stored. Salivary and lacrimal flow, salivary gland ultrasonography (SGUS), and patient-related outcome measures were analysed. A lip salivary gland biopsy was performed at baseline and upon development of symptoms suggestive of pSS. The primary endpoint was the development of definite pSS according to the ACR-EULAR classification criteria.

Results

After the first year of recruitment, 50 individuals (Anti-SSA+ n=27, relatives n=21, incomplete n=2) were screened at baseline, of whom 28 were identified as individuals at risk for pSS and were included in the study. Twenty-two individuals were excluded from the study, most of whom were “relatives” with negative autoantibodies. Of these 28 individuals at risk, 89% were female (n=25), they had a median age of 53 years (IQR: 19) and 57% (n=16) had positive antinuclear antibodies. 86 percent were positive for anti-SSA and 14% were positive for anti-SSB. Decreased complement C3 and C4 were found in 18% and 4%, respectively. Serum IgG concentration was elevated in 29% of individuals. A reduction of lacrimal flow was found in 29% and stimulated whole salivary flow was reduced in 29%. The median of the ESSPRI was 1.6 (3.0). Eight-teen percent of the investigated individuals had a pathological ultrasound [Hocevar score median 4,5 (9,0)] and in 9% a focus score ≥ 1 [median 0.15 (0.57)] was found in the lip salivary gland biopsies. Four patients (14%) met the primary endpoint and were diagnosed with pSS within the first year.

Conclusion

The design of the PRESTIGE study allows us to follow individuals at risk for pSS and will help to unveil symptoms and immune pathology as pSS develops. We suggest to establish a larger international pre-pSS cohort to increase statistical power.

Disclosure of Interests

None declared

AB0471 FIRST SYMPTOMS AT THE ONSET OF PRIMARY SJÖGREN’S SYNDROME – THE PATIENTS’ PERSPECTIVE OF A SNEAKY DISEASE

Background

Primary Sjögren Syndrome (PSS) is an autoimmune disorder with a diverse spectrum of clinical manifestations ranging from sicca symptoms to severe systemic organ involvement. Little is known about the symptoms at the onset of PSS, as these are often ignored by both, patients and physicians leading to a substantial delay of diagnosis.

Objectives

The aim of this study was to investigate patients’ recollection of the first symptoms before diagnosis of PSS in qualitative interviews. The second aim was to verify and quantify these aspects in a representative cohort.

Methods

All PSS patients fulfilled the EULAR/ACR 2016 classification criteria. In the first part of the study, consecutive PSS patients were recruited for individual, semi-structured interviews. A discussion guide with five open-ended questions was developed to explore patients’ experiences on the onset of PSS. All interviews were audio-recorded and transcribed verbatim, and an inductive thematic data analysis was performed using MAXQDA software (VERBI, Berlin, Germany).

In the second part, the identified aspects of the qualitative analysis were grouped to a checklist with ten items. Patients were asked to complete the checklist before their routine clinical assessment.

Results

One-hundred and thirty-four patients participated in the study. The qualitative part was completed by 31 PSS patients; 90.3% (n=28) were female and patients had a mean disease duration of 6.9 years (±5.7(SD)) and a mean age of 58.1 years (±12.6).

Four different major aspects emerged of how patients experienced the beginning and first symptoms of PSS: (1) sicca symptoms started after initial swelling of parotis and/or lymph nodes (2) “Classic” PSS symptoms (fatigue, pain, dryness): patients reported wandering joint pain before diagnosis with a long time apart from first symptoms until diagnosis. Patients described joint pain, chronic malaise, and fatigue over months. (3) Hormonal changes (e.g. after birth, hysterectomy) or infections before the onset of PSS symptoms. (4) Slowly progressing discomfort due to sicca: patients reported a slow progression of symptoms with no initial recognition of sicca discomfort. In these patients recurrent dental problems and loss of teeth in the years prior to diagnosis was common.

In the second part of the study, the four themes were verified in an independent cohort of 103 PSS patients. Patients were 59.9 (±13.7) years old and six patients were male. The main symptom before diagnosis was dryness (n=77, 74.8%) with wandering joint pain (n=51, 49.5%) and fatigue (n=47, 45.6%). In 38.8% (n=40), patients reported a swelling/inflammation of the parotid gland at the onset of disease.

Conclusion

We identified four themes describing the initial symptoms of PSS. Raising awareness of these symptoms among physicians and among the general public may allow earlier diagnosis of PSS.

Disclosure of Interests

None declared

AB0732 Abatacept as therapy option in systemic sclerosis (SSc) patients after years of Grazer- protocol treatment- Our Experience

Background

Previous studies have provided evidence that T cells may play a significant role in the pathogenesis of systemic sclerosis (SSc) and observational studies reported that Abatacept, which interferes with T cells activation, appeared to be safe and effective in SSc-patients with skin and muscle involvement. So far, there was no significant effective treatment for SSC-ILD. We have recently demonstrated the effectiveness of intensified –RTX- long term treatment (“Grazerprotocol” with 500 mg RTX in week 0 and 2, every 3 months +/- MMF) in SSc patients with severe organ involvement and/or progressive form non responding to methotrexate or cyclophosphamide. However, no data are available concerning how long Patients with a stable disease need to be treated. B-cell-depletion therapy over years for SSC in remission might represent a risk factor for infections. Additionally, the parenteral administration is associated with an increase in health care and patients are bound to regular hospital visits, which is a limiting factor for life quality.

Objectives

We aimed to investigate if subcutaneous Abatacept could be used as a maintenance treatment in SSc-patients reaching a stable disease activity after a treatment with RTX administered according to our Grazer protocol over several years.

Methods

In this retrospective analysis, we retrieved data from 20 patients who fulfilled the diagnosis criteria for systemic sclerosis (SSc) according to the European League Against Rheumatism Scleroderma Trial and Research standards, who started a treatment with abatacept (ABA) after years of 500 mg RTX therapy every three months +/- MMF (Grazer protocol). The following clinical parameter were evaluated: modified Rodnan Skin Score (mRSS), Systemic Sclerosis Activity Score (SScAS), Systemic Sclerosis Severity Score (SScSS) and lung diffusing capacity for carbon monoxide (DLCO). Lab parameters like IgG, ANA, ENA and inflammation parameters were routinely assessed. Clinical data from baseline visit (BSL) (before ABA treatment start) and follow-up visit (FU) (after 6 months of treatment) were collected.

Results

We included 20 SSc patients in this retrospective analysis who changed from RTX to Abatacept. The majority were female (n=16; 94.1%), with a mean age ±SD of 54.8 years ±11 and an average disease duration of 7.7 years ±4.5. In 17.9% (n=4) treatment needed to be stopped due to disease flare after three months (lung n=2, skin and tendons n=2).

However, interestingly, Abatacept further decreased significantly mRSS between baseline visit and follow-up visit regarding the affected skin of the fingers. Thus, the mRSS went from 3.9±3.4 to 2.5±1.8 (p<0.05). As expected, no significant difference in the EUSTAR-SScAS, or ScSS or DLCO was found. No infections were observed during the abatacept follow-up period and Immunoglobulins remained within the normal range.

Conclusion

Abatacept might be a feasible option as a maintenance therapy after intensive immunomodulation with RTX and may give our patients the possibility to further improve their quality of life.

The fact that 4 patients experienced a relapse after switching to Abatacept warrants further studies to find prognostic factors.

Disclosure of Interests

None declared

POS0102 GO ASK YOUR PATIENTS! PSS-QoL REPORTED PERCEPTION OF DRYNESS CORRELATES WITH LACRIMAL AND SALIVARY FLOW IN PRIMARY SJÖGREN’S SYNDROME

Background:

The patient perspective is an essential outcome parameter in the quest for effective therapy in primary Sjögren’s Syndrome (PSS). The EULAR Sjögren’s Syndrome Patient Reported Index (ESSPRI) is recommended by EULAR to quantify patient’s symptom burden and has been used in several clinical trials. Surprisingly, the patient’s perception of dryness quantified with ESSPRI does not correlate with objective measures of salivary or lacrimal flow.

Objectives:

Thus, we evaluated a newly developed assessment tool-the Primary Sjögren’s Syndrome Quality of Life Questionnaire (PSS-QoL) - for quantifying symptoms of dryness in comparison with the ESSPRI and objective measurements of salivary and lacrimal flow.

Methods:

Data of patients from the PSS registry of the Medical University of Graz fulfilling the 2016 ACR/EULAR classification criteria for PSS were analysed. The patient perspective was analyzed by PSS-QoL, ESSPRI, Xerostomia Inventory (XI) and Ocular Surface Disease Index (OSDI). Sicca signs were measured with Schirmer’s test, unstimulated salivary flow test (USF) and stimulated salivary flow test (SSF). Patients were categorized into groups based on the presence of subjective and/or objective dryness: 1) objective dryness only, 2) subjective dryness only, and 3) both, subjective and objective dryness. ESSDAI (EULAR Sjögren’s Syndrome Disease Activity Index) and EGA (Evaluator Global Assessment, numeric rating scale from 0 to 10) were obtained. In addition, free light chains (FLC) ĸ and λ, rheumatoid factor (RF) IgM and IgA were determined.

Results:

Data from 123 PSS patients were analyzed; 91.9% (n=113) were female, with a mean disease duration of 6.2 (±5.3) years and mean age of 60.1 (±12.4) years. PSS-QoL-dryness revealed significant negative correlations with Schirmer’s test (r=-0.31, p<0.05) and SSF-test (r=-0.39, p<0.01). In contrast, we found no significant correlation between ESSPRI-dryness and any objective dryness test. Lower perceived dryness was associated with higher immunological activity determined by increased levels of IgG, FLC and RF-IgA. Patients with objective signs and subjective symptoms of dryness had higher clinical and immunological disease activity compared to patients with subjective symptoms only (table 1).

Table 1.

Comparison of perceived dryness-groups with clinical parameters

PSS-QoL MouthpPSS-QoL Eyespsubjobj/subjsubjobj/subjEGA1.0 [0-5]2.0 [0-7]<0.051.0 [0-3]2.0 [0-7]<0.05ESSDAI1.0 [0-144.0 [0-15<0.053.0 [0-74.0 [0-15nsESSPRI-pain3.0 [0-9]3.0 [0-10]ns4.0 [1-8]3.0 [0-10]<0.05RF-IgM19.0 [5-524]31.0 [7-417]ns10.0[5-33]26.0[7-524]<0.01FLC-λ15.1 [7.0-68.3]20.1 [2.6-124.0]<0.0113.4 [7.0-54.5]18.7[2.6-124.0]<0.01IgG11.9 [6.5-37.2]16.1 [7.4-33.8]ns12.8 [6.5-20.6]14.8[7.4-37.2]nsC40.2 [0.01-0.41]0.17 [0.00-0.43]<0.010.2 [0.09-0.41]0.18 [0.00-0.43]nsRF-IgA11.0 [1-500]103 [0-500]<0.014.5 [1-465]63 [0-500]<0.01

C4=Complementfactor 4; EGA=Evaluators Global Assessment; ESSDAI=EULAR Sjögren Syndrome Disease Activity Index; ESSPRI=EULAR Sjögren Syndrome Patient Reported Index; FLC-λ=Free light chain Lambda; IgG=Immunoglobulin G; obj/subj=objective and subjective dryness-group; PSS-QoL=Primary Sjögren Syndrome Quality of Life Questionnaire; RF-IgA=rheumatoid factor Immunoglobulin A; RF-IgM=rheumatoid factor Immunoglobulin M; subj=subjective dryness-group.

Conclusion:

Patients’ perception of dryness assessed by PSS-QoL correlates with objective measurements of salivary gland function while ESSPRI-dryness did not. Based on the PSS-QoL and objective measures of dryness two distinct groups of PSS patients could be distinguished, which may have implications in daily practice and future clinical studies.

Disclosure of Interests:

None declared

AB0146 DRUG DEPENDENT ALTERATIONS IN B-CELL REPERTOIRE IN SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS WITH LOW DISEASE ACTIVITY

Background:

B-cells play a major role in the pathogenesis and perpetuation of the immune response in systemic lupus erythematosus (SLE). So far, B-cell subtypes have been studied well, but the precise mechanisms of the B-cell alterations during disease activity and during remission, depending on different medication, are still unclear.

Objectives:

The aim of our study was to investigate the drug dependent alterations in the B-cell repertoire of SLE patients with low disease activity (SLEDAI – 2K ≤4).

Methods:

Peripheral blood samples from 39 patients suffering from SLE (mean±SD; age 43±13 years, 87.2% females, disease duration 11.1±7 years) were drawn over 2 years. All SLE patients were in remission or low disease activity (median±SE, SLEDAI of 2.0±1.5). B-cells were characterized using CD19, CD20, CD5, CD27 antibodies and were grouped in naïve (IgD+27-), non-switched memory (IgD+, CD27+), memory (IgD-,CD27+), B1 (CD5+27-) and MBL-like (CD5++) B-cells. A quantitative flow cytometric bead-based assay (QuantiBRITE PE kit from Becton Dickinson) was used for the estimation of CD19 antibodies bound per cell. Further, CD38 and CD86 antibodies were used to characterize the B-cell subsets. All cytometric measurements were performed using a standardized BD LSR Fortessa platform. After 3 years of follow-up, patients’ data about disease activity and current medication were obtained.

Results:

22 SLE patients were treated with hydroxychloroquine (85.8%) and 19 patients received mycophenolate mofetil (MMF; n=14; 54.6%) or azathioprine (AZA; n= 5; 19.5 %). 5 patients were treated with other DMARDs. Independently of hydroxychloroquine and/or MMF, no significant differences were seen in naïve, non-switched memory, post-switched memory, plasma blasts, B1- or MBL-like B-cells. Patients treated with AZA had significantly lower naïve B-cells (mean±SD, 39.3±6.7vs. 73.1±19.3 %; p = 0.028), but had significantly higher IgD-post switched B-cells (31.2±9.1 vs.12.5 ±9.2 %; p = 0.028, respectively) compared with no AZA-treatment. Interestingly, activated B-cells (5.5±1.5 vs. 1.8±1.1%; p = 0.009) were significantly higher in AZA-treated. After 3 years of follow-up, almost all patients were in remission (median±SE, SLEDAI of 2.0±2.0), except of 3 patients with a SLEDAI of ≥ 6. Interestingly, those patients had at baseline, statistically higher naïve B-cells (p = 0.041) and lower B1-like B-cells (p =0.020) compared with patients with low disease activity.

Conclusion:

Our results suggest that independently of hydroxychloroquine and/or MMF treatment, all patients with low disease activity had similar normal B-cell subsets. Interestingly, in the small group of patients who were treated with AZA, a reduced regeneration of B-cells was shown. Patients with higher disease and high naïve B-cells showed an increased disease activity after three years.

Acknowledgments:

The research was performed in “CBmed” and funded by the Austrian Federal Government within the COMET K1 Centre Program, Land Steiermark and Land Wien.

Disclosure of Interests:

None declared

THU0031 ABATACEPT ALTERS THE FREQUENCY OF IMMUNOREGULATORY AND EFFECTOR T CELL SUBPOPULATIONS IN RHEUMATOID ARTHRITIS

Background:

Under physiological conditions, T regulatory cells (Tregs) are responsible for the downregulation of the immune response. In autoimmune diseases, such as rheumatoid arthritis (RA), auto-inflammation is driven by an imbalance of activation and downregulation of immunological pathways. Thus, treatment plans for autoimmune diseases often involve the enhancement of immunoregulatory pathways by administering inhibitors of costimulation, i.e. CTLA-4-Ig (abatacept, ABA). ABA binds specifically to CD80 and CD86 on antigen presenting cells (APC). Consequently, T cell activation via the CD28 receptor is blocked. Previous studies have demonstrated surprising effects of abatacept on Tregs, specifically decreased frequency of these cells but enhancement in their function1. Whether these alterations can only be found in patients with ABA treatment, or whether they are also present in patients receiving other anti-inflammatory drugs is currently unknown.

Objectives:

The aim of our research was to delineate the impact of ABA on the different subsets of effector and regulatory T cells in RA and compare these findings with patients receiving tocilizumab (TCZ) or rituximab (RTX).

Methods:

Peripheral blood samples from 56 RA patients (median ± SE; age: 60.5 ± 1.3 years, female ratio: 0.7, disease duration: 17.9 ± 2.1 years; respectively) were drawn over a sampling period of 2 years. Freshly isolated PBMCs of RA patients were stained with fluorochrome-labelled antibodies and T cell subsets were identified by flow cytometric means. CD3+CD4+T cells were further classified using different T cell markers (CD25, CD127, CD39, CD95). All cytometric measurements were performed using a standardized BD LSR-Fortessa platform. RA patients were compared according to their treatment with ABA, TCZ or RTX.

Results:

Eighteen out of 56 RA patients (32%) received ABA, 25 patients (45%) received TCZ and 13 patients (23%) were under CD20+ cell depletion therapy with RTX. RA patients receiving ABA displayed a significant decrease in CD3+CD4+CD25+CD127dimTregs (3.7% ± 0.4) compared to patients with TCZ (5.4% ± 0.4, p = 0.041) and patients under RTX treatment (7.52% ± 0.93, p = 0.026). CD39+Tregs were significantly higher in RA patients treated with TCZ (49.5% + 3.2, p = 0.000) or RTX (50.5% ± 5.3, p = 0.026) compared to patients receiving ABA (24.5% ± 3.1). In addition, the frequency of CD95+Tregs was significantly reduced in ABA patients compared to RTX patients (59.6% ± 3.1 vs.76.7% ± 3.6, p = 0.014; respectively). Interestingly, T cells displaying an effector T cell phenotype (CD3+CD4+CD25+/-CD127+) were increased in ABA treated patients compared to RTX treated patients (59.6% ± 3.1 and 76.7% ± 3.6, p = 0.002). Since none of our patients were a non-responder or had high disease activity, we could not analyse whether these changes are associated with treatment outcome.

Conclusion:

Our data demonstrate that blockage of T cell stimulation via ABA leads to characteristic alterations in different regulatory and effector T cells not seen in patients treated with TCZ or RTX. Further studies must clarify whether the analysis of regulatory and effector T cell subpopulations before treatment initiation can be used as biomarker for treatment response.

References:

[1]Álvarez-Quiroga C, Abud-Mendoza C, Doníz-Padilla L, et al. CTLA-4-Ig therapy diminishes the frequency but enhances the function of treg cells in patients with rheumatoid arthritis.J Clin Immunol. 2011;31(4):588-595.doi:10.1007/s10875-011-9527-5

Acknowledgments:

Work done in “CBmed” was funded by the Austrian Federal Government within the COMET K1 Centre Program, Land Steiermark and Land Wien.

Disclosure of Interests:

None declared

AB0746 EVALUATING TENDER AND SWOLLEN JOINTS FOR THE ASSESSMENT OF INFLAMMATORY PAIN IN PSORIATIC ARTHRITIS USING ULTRASOUND

Background:

Tender and Swollen Joint Counts (TJC, SJC) are items of disease activity scores in rheumatoid arthritis (RA) and psoriatic arthritis (PsA). Recent studies suggest that TJC do not adequately reflect ongoing inflammation in RA when using Ultrasound (US) as a reference standard, and that pain might be due to other, non-inflammatory causes.1, 2In PsA, the role of tenderness and swelling of joints for reflecting active inflammation has not been well studied so far.

Objectives:

To evaluate tender (TJ) and swollen joints (SJ) for the assessment of inflammation in PsA.

Methods:

We performed a prospective study on 83 PsA patients undergoing clinical and ultrasound examinations at two study visits scheduled 12 months apart. Tenderness and swelling were assessed for 68 and 66 joints respectively and US examinations, including grey scale (GS) and power doppler (PD) were conducted at all 68 joints. GS- (range 0-204) und PD sum scores (0-204) were calculated. At patient level, correlations were performed between TJC, SJC and clinical or US values. At joint level a GS value≥1 and/or PD value≥1 was defined as active synovitis, which was compared to whether a joint was tender, swollen or both. A generalized linear mixed model was created to assess the predictive value of TJ and SJ for active synovitis after 12 months, taking into consideration the joint site.

Results:

At baseline the median TJC and SJC for 83 patients was 4 (range 0-59) and 1 (0-20), respectively and the median GSS- and PD sum score was 16 (3-56) and 3 (0-31) respectively. SJC correlated with the GSS sum score (r= 0.37, p=0.004) and PD sum score (r =0.47, p<0.001), while TJC only correlated with PD sum score (r=0.33, p=0.01). TJC correlated better than SJC with patient reported outcomes like patient global assessment (TJC: r=0.57, p<0.001; SJC r=0.39, p=0.002) and health assessment questionnaire (TJC: r=0.50, p<0.001, SJC no significant correlation). Swollen joints (with or without tenderness) showed active synovitis (GSS≥1 and/or PD≥1) in 67.6% of cases, while tender joints (with or without swelling) showed signs of US activation in only 34.5%. A joint that was considered swollen at baseline was more likely to express active synovitis after 12 months (OR: 4.3, 97.5 CI: 2.9-6.2), compared to a joint that was either tender or swollen at baseline (OR: 2.8, 97.5 CI: 2.1-3.5).

Conclusion:

SJC are more closely linked with US signs of inflammation as compared to TJC in PsA. While swelling of a joint predicts US inflammation after a year, the information whether the joint is additionally tender or not, gives no additional predictive information.

References:

[1]Hammer HB, Michelsen B, Sexton J, et al. Swollen, but not tender joints, are independently associated with ultrasound synovitis: results from a longitudinal observational study of patients with established rheumatoid arthritis.Ann Rheum Dis2019;78:1179-85.

[2]Hammer HB, Michelsen B, Provan SA, et al. Tender joint count may not reflect inflammatory activity in established rheumatoid arthritis patients - results from a longitudinal study.Arthritis Care Res (Hoboken) 2018

Disclosure of Interests:

None declared

Anti-spike IgG causes severe acute lung injury by skewing macrophage responses during acute SARS-CoV infection

Newly emerging viruses, such as severe acute respiratory syndrome coronavirus (SARS-CoV), Middle Eastern respiratory syndrome CoVs (MERS-CoV), and H7N9, cause fatal acute lung injury (ALI) by driving hypercytokinemia and aggressive inflammation through mechanisms that remain elusive. In SARS-CoV/macaque models, we determined that anti-spike IgG (S-IgG), in productively infected lungs, causes severe ALI by skewing inflammation-resolving response. Alveolar macrophages underwent functional polarization in acutely infected macaques, demonstrating simultaneously both proinflammatory and wound-healing characteristics. The presence of S-IgG prior to viral clearance, however, abrogated wound-healing responses and promoted MCP1 and IL-8 production and proinflammatory monocyte/macrophage recruitment and accumulation. Critically, patients who eventually died of SARS (hereafter referred to as deceased patients) displayed similarly accumulated pulmonary proinflammatory, absence of wound-healing macrophages, and faster neutralizing antibody responses. Their sera enhanced SARS-CoV-induced MCP1 and IL-8 production by human monocyte-derived wound-healing macrophages, whereas blockade of FcγR reduced such effects. Our findings reveal a mechanism responsible for virus-mediated ALI, define a pathological consequence of viral specific antibody response, and provide a potential target for treatment of SARS-CoV or other virus-mediated lung injury.

The self-curing phenomenon of schistosome infection in rhesus macaques: insight from in vitro studies

A reduction in the burden of schistosomiasis is potentially achievable by integrating a schistosomiasis vaccine with current control measures. Here, we determine parasite-specific in vitro responses of B, T, and NK cells from naive uninfected rhesus macaques to Schistosoma mansoni (Sm) egg (SmEA) and worm antigen (SmWA) preparations isolated from infected baboons. Pronounced B cell responses to SmEA and NK cell responses to both SmEA and SmWA were observed. High levels of IL-2 and IL-21 responses against Sm antigens were observed in T and non-T cells of lymph nodes (LNs) and gut lamina propria-derived lymphocytes (LPLs). Data analysis showed multifunctionality of LN-derived CD4⁺ , CD8⁺ , and CD4⁺ CD8⁺ double positive T cells against either SmWA or SmWA+SmEA antigen preparations. Distinct SmEA-specific multifunctional responses were observed in gut LPLs, suggesting simultaneous responses against egg antigens. These data provide insight into the immune effectors involved in schistosome responses by rhesus macaques.

Effects of temporary BLyS treatment of rhesus macaques

BLyS is a survival cytokine that regulates peripheral B cell numbers and transitional B cell throughput. In mice, exogenous BLyS administration yields elevated pre-immune B cell numbers, an increased proportional representation of transitional B cells, and shifts in repertoire composition (1–3). Consistent with these observations, BLyS pretreatment alters the quality of antibody responses to HIV gp140 in mice, yielding enhanced neutralizing responses (4). While it is assumed that BLyS plays analogous roles in other species, similar studies in nonhuman primates are lacking. Accordingly, we have assessed the effects of exogenous BLyS treatment in rhesus macaques. Here we treated juvenile rhesus macaques with 0.05 mg/kg recombinant human BLyS over ten days. Physical exams and blood cell counts indicate no adverse effects of treatment except a decrease in lymphocyte counts during the treatment periods. We find that the numbers and proportional representation of transitional B cells (CD20+ IgM+ CD10+) increase during and immediately following BLyS treatment, returning to pre-treatment levels within 20–30 days. There is a small increase in plasma anti-dsDNA antibody, and a significant increase in anti-recombinant human BLyS antibody indicating immunogenicity in this species. Together, these results indicate that BLyS plays similar roles in rodents and primates. They further suggest that deliberate manipulation of BLyS may be an effective approach in rhesus macaques for expanding B cell repertoire diversity and altering the quality of antibody responses.

Anti-spike IgG exacerbates lung injury by skewing monocyte-macrophage responses during SARS-CoV infection

Deceased SARS patients displayed severe acute lung injury (ALI) with exuberant inflammatory responses yet faster neutralizing IgG development. The mechanism underlying this discrepancy remains elusive. Here, we combine vaccination and passive immunization strategies to determine whether anti-spike (S) IgG modulates SARS-CoV-mediated lung injury in Chinese rhesus macaques. We found that macaques pre-vaccinated with MVA-S displayed more severe lung injury compared with MVA-vaccinated controls after SARS-CoV challenge. Moreover, passive immunization of purified anti-spike IgG but not control IgG resulted dose-dependently in enhanced lung infection and severer lung injury, associated with prolonged responses of pro-inflammatory alveolar MAC387+ and CD163+TGF-b− macrophages, IL-6 production and delayed wound-healing CD163+TGF-b+ macrophages response. Consistently, accumulated pro-inflammatory CD163+TGF-b− macrophages were found in lungs of deceased SARS patients. Our results demonstrated that anti-spike IgG exacerbates lung injury likely by enhancing infection and skewed alveolar monocyte-macrophage responses, which may have significant implications to CoV-mediated pathogenesis and immunotherapy.

Infection with non-CD4 tropic variant of SIVmac239 accelerates the formation of mature germinal center reactions and elicits antigen specific B cell responses

Background

What determines the development of germinal centers (GCs) in lymph nodes (LNs) early after HIV/SIV infection is likely to be crucial for developing neutralizing antibodies and B cell memory.

Materials and Methods

Rhesus macaques were inoculated i.v. with either SIVmac239 (n=2) or iMac239ΔD385 (iMacΔD) (n=4), a CD4-independent variant of SIVmac239 lacking a CD4 binding site (J. Virol. 90:4966, 2016). LNs from different time points were analyzed using polychromatic flow cytometry and multiplexed confocal imaging.

Results

In contrast to SIVmac239, iMacΔD infection was associated with relative preservation of total and CD28hiCD95hi memory CD4 T cells, consistent with its compromised capacity to target CD4 T cells. Imaging analysis revealed accelerated formation of mature, polarized GCs in iMacΔD compared to SIVmac239 infected animals, a profile associated with i) increased frequencies of PD-1hiBcl-6hi CD4 T cells, ii) higher levels of IL-10 and IL-21 within the follicles, iii) increased frequency of PH2AX+ (a required factor for isotype switching) B cells, iv) lower levels of Fas-L in the follicular areas, associated with lower TUNEL (cell death) positivity and v) lower accumulation of CD163+ cells (monocytes/macrophages; a surrogate of local inflammation) in proximity to follicles. The observed GC dynamics associate with earlier virus-specific antibody responses in iMacΔD compared to SIVmac239.

Conclusions

Our data indicate that CD4 tropism of SIV greatly affects the development of GC reactions early after infection. The iMacΔD model could provide critical information on how GC reactions can be manipulated to augment the generation of neutralizing antibodies and B cell memory.

Pharmacologic rationale for the NK1R antagonist, aprepitant as adjunctive therapy in HIV

BACKGROUND

Many HIV infected individuals with suppressed viral loads experience chronic immune activation frequently developing neurological impairment designated as HIV associated neurocognitive disorder (HAND). Adjunctive therapies may reduce HIV associated inflammation and therefore decrease the occurrence of HAND.

METHODS

We have conducted in vitro, animal and clinical studies of the neurokinin 1 receptor (NK1R) antagonist aprepitant in HIV/SIV infection.

RESULTS

Aprepitant inhibits HIV infection of human macrophages ex vivo with an ED50 ~ 5 µM. When administered at 125 mg once daily for 12 months to SIV-infected rhesus macaques, aprepitant reduced viral load by approximately tenfold and produced anti-anxiolytic effects. The anti-viral and anti-anxiolytic effects occur at approximately the third month of dosing; and the effects are sustained throughout the duration of drug administration. Protein binding experiments in culture media and animal and human plasma indicate that the free fraction of aprepitant is lower than previously reported supporting usage of higher doses in vivo. The analysis of blood samples from HIV positive individuals treated for 2 weeks with aprepitant at doses up to 375 mg demonstrated reduced levels of pro-inflammatory cytokines including G-CSF, IL-6, IL-8 and TNFα. Decreased pro-inflammatory cytokines may reduce HIV comorbidities associated with chronic inflammation.

CONCLUSIONS

Our results provide evidence for a unique combination of antiretroviral, anti-inflammatory and behavioral modulation properties of aprepitant in vitro and in vivo. These results provide robust support for a clinical exposure target above that recommended for chemotherapy-induced nausea and vomiting. Doses up to 375 mg once daily in HIV-infected patients still elicit sub-therapeutic exposure of aprepitant though effective plasma concentrations can be achievable by proper dose modulation.

Distinct impact of SIV infection in interstitial and alveolar lung macrophages on the pathogenesis of lung disease in rhesus macaques (VIR9P.1147)

Declining CD4+ T cells during HIV infection contributes to immunodeficiency, but we recently reported that increasing monocyte turnover better predicted onset of terminal disease progression to AIDS in SIV-infected rhesus macaques. Here we describe the kinetics of SIV infection on distinct lung macrophage subsets and on monocyte/macrophage turnover rates in relation to pulmonary disease progression in rhesus macaques. Monocyte and tissue macrophage turnover were monitored by in vivo BrdU injection and cell uptake. Cell-associated SIV DNA in lung tissue was quantified by qPCR and in situ hybridization. Massive SIV infection was associated with increasing death rate of shorter-lived lung interstitial macrophages (IM) with elevated monocyte turnover and progression to AIDS. Conversely, the turnover of alveolar macrophages (AM) and decreasing numbers of CD4+ T cells in lung tissue did not directly correlate with disease progression. SIV DNA levels within IM and AM of the lung increased as monocyte turnover increased, but did not change within lung CD4+ T cells regardless of the stage of disease. These data suggest that SIV infection and concurrent destruction of lung IM contribute to pulmonary pathogenesis during AIDS progression while the longer-lived AM that become infected may contribute to establishing a virus reservoir. Also, bronchoalveolar lavage (BAL) specimens contain AM but not IM, so may be insufficient for fully evaluating macrophage-mediated responses in the lung.

Potentially neutralizing B cell clonotypes are eliminated at peripheral selection checkpoints (LYM6P.768)

B lymphocyte stimulator (BLyS) signals via BR3 mediate selection and survival in the transitional, mature, and germinal center B cell pools. We have previously shown that treatment of mice with exogenous BLyS prior to immunization with HIV-1 envelope (Env) trimers improves neutralizing antibody breadth and potency. We are therefore investigating the hypothesis that broadly neutralizing B cell clonotypes are rare because of counter-selection at the transitional or germinal center checkpoints. Here we show that Env-specific murine B cells in pre-immune, germinal center, and memory B cell subsets can be visualized and tracked by flow cytometry using a biotinylated Env probe. Initial results indicate loss of Env+ B cells at both the transitional developmental stage and in the germinal center following immunization. As a first step in testing the feasibility of a BLyS pre-immunization treatment approach in nonhuman primates, we show that BLyS enhances survival of quiescent and dividing rhesus macaque B cells in vitro.

Expression levels of 10 candidate genes in lung tissue of vaccinated and TB-infected cynomolgus macaques

The expression of ten tuberculosis candidate genes in lung and lymph nodes of cynomolgus macaques vaccinated and experimentally infected with Mycobacterium tuberculosis (Mtb) was quantified. The expression of TNFα, IL10, IL1β, TLR4, IL17, IL6, IL12, and iNOS in the lungs of vaccinated animals was higher than that of non-vaccinated animals.

Monocyte/macrophages and their role in HIV neuropathogenesis

Neurological sequelae of human immunodeficiency virus (HIV) infection have been and remain a significant problem. Monocytes and macrophages in humans and monkeys are susceptible to infection by HIV and simian immunodeficiency virus (SIV), and are considered to be a main mechanism by which the central nervous system (CNS) is infected. Within the infected CNS, perivascular macrophages and, in some cases, parenchymal microglia are infected as are multinucleated giant cells when present. While neurons are not themselves directly infected, neuronal damage occurs within the infected CNS. Despite the success of antiretroviral therapy (ART) in limiting virus in plasma to non-detectable levels, neurological deficits persist. This review discusses the continued neurological dysfunctions that persist in the era of ART, focusing on the roles of monocyte and macrophage as targets of continued viral infection and as agents of pathogenesis in what appears to be emergent macrophage-mediated disease resulting from long-term HIV infection of the host. Data discussed include the biology of monocyte/macrophage activation with HIV and SIV infection, traffic of cells into and out of the CNS with infection, macrophage-associated biomarkers of CNS and cardiac disease, the role of antiretroviral therapy on these cells and CNS disease, as well as the need for effective adjunctive therapies targeting monocytes and macrophages.

Neuroendocrine adenoma of the middle ear (NAME) mimicking as chronic otitis media with an episode of facial nerve palsy

OBJECTIVES

To increase awareness of neuroendocrine adenomas of the middle ear (NAME), rare lesions often mistaken for other entities or chronic otitis media. Histogenesis remains controversial, although the consensus tends toward a pluripotent stem cell of the middle ear mucosa as the origin of the lesion. The tumour is characterised by dual differentiation with exocrine and endocrine components. The most common symptoms are conductive hearing loss, tinnitus and vertigo. The treatment of choice is complete surgical removal of the tumour with no adjuvant radiotherapy being required.

CASE REPORT

We report the case of a 23-year-old man presenting with chronic otitis media, conductive hearing loss, vertigo and tinnitus who, some years previously, had suffered from an episode of facial nerve palsy. Conservative therapy failed and so surgery was performed. Tumour-like masses were encountered and histological and immunohistochemical examination revealed a neuroendocrine adenoma of the middle ear.

CONCLUSION

This rare entity should be considered as differential diagnosis when treating chronic inflammatory disease not responding to conservative therapy or dealing with unclear expansive processes of the middle ear. MRI scans should be performed since CT scans are inconclusive.

The macaque gut microbiome in health, lentiviral infection, and chronic enterocolitis

The vertebrate gut harbors a vast community of bacterial mutualists, the composition of which is modulated by the host immune system. Many gastrointestinal (GI) diseases are expected to be associated with disruptions of host-bacterial interactions, but relatively few comprehensive studies have been reported. We have used the rhesus macaque model to investigate forces shaping GI bacterial communities. We used DNA bar coding and pyrosequencing to characterize 141,000 sequences of 16S rRNA genes obtained from 100 uncultured GI bacterial samples, allowing quantitative analysis of community composition in health and disease. Microbial communities of macaques were distinct from those of mice and humans in both abundance and types of taxa present. The macaque communities differed among samples from intestinal mucosa, colonic contents, and stool, paralleling studies of humans. Communities also differed among animals, over time within individual animals, and between males and females. To investigate changes associated with disease, samples of colonic contents taken at necropsy were compared between healthy animals and animals with colitis and undergoing antibiotic therapy. Communities from diseased and healthy animals also differed significantly in composition. This work provides comprehensive data and improved methods for studying the role of commensal microbiota in macaque models of GI diseases and provides a model for the large-scale screening of the human gut microbiome.

Bacterial mutualists within the gastrointestinal tract aid digestion, promote development of the gut immune system, and provide competitive barriers to pathogen invasion. The host, in return, provides bacteria with safe housing and food during lean times. The composition of the gut microbiota is controlled in part by the host immune system. In a variety of disease states, immune function can be altered, and gut morbidity is often associated, leading to the hypothesis that alterations in the GI microbiota may contribute to disease. In this study, the gut microbiota was characterized in 100 samples from rhesus macaques using pyrosequencing, which allowed 141,000 sequences from 16S rRNA genes to be generated and analyzed. Healthy animals were compared to animals with gut disorders, induced, for example by advanced simian AIDS. Many factors contributed to changes in the microbiota, including the sex of the animal of origin. Animals with chronic colitis showed differences in composition of the GI microbiota compared to healthy animals, providing an association between altered microbiota and disease.

Control of viremia and preservation of intestinal CD4+ T cells in SHIVsf162P3 infected macaques intravenously challenged with pathogenic SIVmac251 (B197)

Attenuated vaccines in primates have provided better protection than most approaches to date. We hypothesized that SHIVsf162P3 infection might “immunize” macaques against intravenous challenge with a highly pathogenic virus. Twelve rhesus macaques of Chinese (Ch) and 2 of Indian (In) origin were intravaginally infected with SHIVsf162P3 and followed until their level of virus had subsided to undetectable or very low levels in plasma. SHIV vaccinated macaques were challenged intravenously with either 100, 10TCID50 SIVmac251 or plasma with high viral loads. Four “naïve” Ch macaques were similarly challenged with SIVmac251 as controls. Remarkably, Ch macaques “immunized” with SHIVsf162P3 were able to control viral replication of pathogenic SIVmac compared to naive (non-immunized) Ch controls. Viral loads after challenge in immunized Ch macaques ranged from undetectable to 104 in plasma compared to105 to 107 in naïve Ch controls. Indian macaques had higher levels of virus than Ch-macaques. but had better levels of protection compared to naïve challenged macaques. Control (naïve) macaques had rapid depletion of intestinal CD4+ T cells but levels remained fairly stable in immunized macaques. Control of viral load in “immunized” macaques did not correlate with the presence of neutralizing antibody and/or cell-mediated immune responses. Combined, these data suggest that effective control of SIV replication through immunization may be possible, but correlates of resistance have yet to be determined.

Substance P is responsible for physiological alterations such as increased chloride ion secretion and glucose malabsorption in cryptosporidiosis

Cryptosporidiosis, caused by the protozoan parasite Cryptosporidium, causes self-limited diarrhea in immunocompetent hosts and severe life-threatening diarrhea in AIDS patients. Highly active antiretroviral therapy has been used to effectively treat cryptosporiosis in some but not all AIDS patients. Therefore, there is an urgent need for innovative drugs to treat this disease. Cryptosporidium infection results in intestinal pathophysiological changes such as glucose malabsorption, increased chloride ion (Cl(-)) secretion, and epithelial barrier disruption, leading to disease pathogenesis. In order to develop tools to combat this opportunistic pathogen, it is vital to understand mediators involved in disease pathogenesis. Substance P (SP), a neuropeptide and pain transmitter, is located in the gastrointestinal tract. SP can cause Cl(-) secretion in human gastrointestinal explants. However, its role in cryptosporidiosis has not been fully studied. Jejunal samples from macaques before and after Cryptosporidium parvum infection were assayed for SP and SP receptor mRNA and protein levels by reverse transcription-PCR and by immunohistochemistry and enzyme-linked immunosorbent assay, respectively. The role of SP in pathophysiological alterations, such as Cl(-) secretion and glucose malabsorption, was studied using tissues derived from macaques infected with C. parvum by the Ussing chamber technique. SP and SP receptor mRNA and protein expression levels were increased in jejunal samples following C. parvum infection and were accompanied by increased basal ion secretion and glucose malabsorption. In vitro treatment of samples obtained from infected macaques with the SP receptor antagonist aprepitant (Emend; Merck, Whitehouse Station, NJ) completely reversed the increase in basal ion secretion and corrected the glucose malabsorption. Our findings raise the possibility of using SP receptor antagonists for the treatment of symptoms associated with cryptosporidiosis.

Simian immunodeficiency virus envelope compartmentalizes in brain regions independent of neuropathology

Simian immunodeficiency virus (SIV) and human immunodeficiency virus (HIV) gp160s obtained from the brain are often genetically distinct from those isolated from other organs, suggesting the presence of brain-specific selective pressures or founder effects that result in the compartmentalization of viral quasi-species. Whereas HIV has also been found to compartmentalize within different regions of the brain, the extent of brain-regional compartmentalization of SIV in rhesus macaques has not been characterized. Furthermore, much is still unknown about whether phenotypic differences exist in envelopes from different brain regions. To address these questions, env DNA sequences were amplified from four SIVmac239-infected macaques and subjected to phylogenetic and phenetic analysis. The authors demonstrated that sequences from different areas of the brain form distinct clades, and that the long-term progressing macaques demonstrated a greater degree of regional compartmentalization compared to the rapidly progressing macaques. In addition, regional compartmentalization occurred regardless of the presence of giant-cell encephalitis. Nucleotide substitution rates at synonymous and nonsynonymous sites (ds:dn rates) indicated that positive selection varied among envelopes from different brain regions. In one macaque, envelopes from some but not all brain regions acquired changes in a conserved CD4-binding motif GGGDPE at amino acids 382 to 387. Furthermore, gp160s with the mutation G383E were able to mediate cell-to-cell fusion in a CD4-independent manner and were more susceptible to fusion inhibition by pooled plasma from infected macaques. Reversion of this mutation by site-directed mutagenesis resulted in reduction of CD4-independence and resistance to fusion inhibition in cell fusion assays. These studies demonstrate that SIV evolution within the brain results in a heterogeneous viral population with different phenotypes among different regions.

B7-H4 expression identifies a novel suppressive macrophage population in human ovarian carcinoma

Tumor-associated macrophages are a prominent component of ovarian cancer stroma and contribute to tumor progression. B7-H4 is a recently identified B7 family molecule. We show that primary ovarian tumor cells express intracellular B7-H4, whereas a fraction of tumor macrophages expresses surface B7-H4. B7-H4⁺ tumor macrophages, but not primary ovarian tumor cells, suppress tumor-associated antigen-specific T cell immunity. Blocking B7-H4-, but not arginase-, inducible nitric oxide synthase or B7-H1 restored the T cell stimulating capacity of the macrophages and contributes to tumor regression in vivo. Interleukin (IL)-6 and IL-10 are found in high concentrations in the tumor microenvironment. These cytokines stimulate macrophage B7-H4 expression. In contrast, granulocyte/macrophage colony-stimulating factor and IL-4, which are limited in the tumor microenvironment, inhibit B7-H4 expression. Ectopic expression of B7-H4 makes normal macrophages suppressive. Thus, B7-H4⁺ tumor macrophages constitute a novel suppressor cell population in ovarian cancer. B7-H4 expression represents a critical checkpoint in determining host responses to dysfunctional cytokines in ovarian cancer. Blocking B7-H4 or depleting B7-H4⁺ tumor macrophages may represent novel strategies to enhance T cell tumor immunity in cancer.

CXCL12 and Vascular Endothelial Growth Factor Synergistically Induce Neoangiogenesis in Human Ovarian Cancers

Ovarian carcinomas have a poor prognosis, often associated with multifocal i.p. dissemination accompanied by intense neovascularization. To examine tumor angiogenesis in the tumor microenvironment, we studied malignant ascites and tumors of patients with untreated ovarian carcinoma. We observed that malignant ascites fluid induced potent in vivo neovascularization in Matrigel assay. We detected a sizable amount of vascular endothelial cell growth factor (VEGF) in malignant ascites. However, pathologic concentration of VEGF is insufficient to induce in vivo angiogenesis. We show that ovarian tumors strongly express CXC chemokine stromal-derived factor (SDF-1/CXCL12). High concentration of CXCL12, but not the pathologic concentration of CXCL12 induces in vivo angiogenesis. Strikingly, pathologic concentrations of VEGF and CXCL12 efficiently and synergistically induce in vivo angiogenesis. Migration, expansion, and survival of vascular endothelial cells (VEC) form the essential functional network of angiogenesis. We further provide a mechanistic basis for explaining the interaction between CXCL12 and VEGF. We show that VEGF up-regulates the receptor for CXCL12, CXCR4 expression on VECs, and synergizes CXCL12-mediated VEC migration. CXCL12 synergizes VEGF-mediated VEC expansion and synergistically protects VECs from sera starvation-induced apoptosis with VEGF. Finally, we show that hypoxia synchronously induces tumor CXCL12 and VEGF production. Therefore, hypoxia triggered tumor CXCL12 and VEGF form a synergistic angiogenic axis in vivo. Hypoxia-induced signals would be the important factor for initiating and maintaining an active synergistic angiogeneic pathway mediated by CXCL12 and VEGF. Thus, interrupting this synergistic axis, rather than VEGF alone, will be a novel efficient antiangiogenesis strategy to treat cancer.

CXCL12 and vascular endothelial growth factor synergistically induce neoangiogenesis in human ovarian cancers

Ovarian carcinomas have a poor prognosis, often associated with multifocal i.p. dissemination accompanied by intense neovascularization. To examine tumor angiogenesis in the tumor microenvironment, we studied malignant ascites and tumors of patients with untreated ovarian carcinoma. We observed that malignant ascites fluid induced potent in vivo neovascularization in Matrigel assay. We detected a sizable amount of vascular endothelial cell growth factor (VEGF) in malignant ascites. However, pathologic concentration of VEGF is insufficient to induce in vivo angiogenesis. We show that ovarian tumors strongly express CXC chemokine stromal-derived factor (SDF-1/CXCL12). High concentration of CXCL12, but not the pathologic concentration of CXCL12 induces in vivo angiogenesis. Strikingly, pathologic concentrations of VEGF and CXCL12 efficiently and synergistically induce in vivo angiogenesis. Migration, expansion, and survival of vascular endothelial cells (VEC) form the essential functional network of angiogenesis. We further provide a mechanistic basis for explaining the interaction between CXCL12 and VEGF. We show that VEGF up-regulates the receptor for CXCL12, CXCR4 expression on VECs, and synergizes CXCL12-mediated VEC migration. CXCL12 synergizes VEGF-mediated VEC expansion and synergistically protects VECs from sera starvation-induced apoptosis with VEGF. Finally, we show that hypoxia synchronously induces tumor CXCL12 and VEGF production. Therefore, hypoxia triggered tumor CXCL12 and VEGF form a synergistic angiogenic axis in vivo. Hypoxia-induced signals would be the important factor for initiating and maintaining an active synergistic angiogeneic pathway mediated by CXCL12 and VEGF. Thus, interrupting this synergistic axis, rather than VEGF alone, will be a novel efficient antiangiogenesis strategy to treat cancer.

Identification of T lymphocytes in simian immunodeficiency virus encephalitis: distribution of CD8+ T cells in association with central nervous system vessels and virus

T lymphocytes are found within brains infected with human immunodeficiency virus (HIV) or simian immunodeficiency virus (SIV) where they are a minor, but consistently identified, population. However, little analysis of their phenotypes has been done, and questions concerning whether or not they are viral antigen specific has not been thoroughly examined. We investigated the central nervous system (CNS) of SIV-infected rhesus macaques to identify T-lymphocyte subsets in relation to virus-infected cells and brain microvessels. We have found that a sensitive antigen-retrieval technique greatly enhanced immunohistochemical detection of CD4+ and CD8+ T lymphocytes in control studies. In encephalitic brains of SIV-infected monkeys with acquired immunodeficiency syndrome (AIDS), we found a significant accumulation of CD8+ T lymphocytes but little-to-no accumulation of CD4+ T lymphocytes. CD4+ cells, when detected, were mostly monocyte/macrophages closely associated with CNS vessels. Using a combination of in situ hybridization for SIV RNA, and immunohistochemistry for CD8+ T lymphocytes and/or Glut-1 for endothelial cells on brain microvessels, we found CD8+ T lymphocytes with an angiocentric distribution often adjacent to virus-infected cells. In the CNS of animals with SIV encephalitis, there was a trend of CD8+ T lymphocytes that were not directly juxtaposed with CNS vessels. These data suggest that in brains of SIV-infected monkeys and HIV-infected humans, CD8+ T lymphocytes traffic to and are retained in the CNS in an angiocentric and possibly antigen-specific manner.

Immunogenicity study of glycoprotein-deficient rabies virus expressing simian/human immunodeficiency virus SHIV89.6P envelope in a rhesus macaque

Rabies virus (RV) has recently been developed as a novel vaccine candidate for human immunodeficiency virus type 1 (HIV-1). The RV glycoprotein (G) can be functionally replaced by HIV-1 envelope glycoprotein (Env) if the gp160 cytoplasmic domain (CD) of HIV-1 Env is replaced by that of RV G. Here, we describe a pilot study of the in vivo replication and immunogenicity of an RV with a deletion of G (DeltaG) expressing a simian/human immunodeficiency virus SHIV(89.6P) Env ectodomain and transmembrane domain fused to the RV G CD (DeltaG-89.6P-RVG) in a rhesus macaque. An animal vaccinated with DeltaG-89.6P-RVG developed SHIV(89.6P) virus-neutralizing antibodies and SHIV(89.6P)-specific cellular immune responses after challenge with SHIV(89.6P). There was no evidence of CD4(+) T-cell loss, and plasma viremia was controlled to undetectable levels by 6 weeks postchallenge and has remained suppressed out to 22 weeks postchallenge.

Dendritic cell subsets differentially regulate angiogenesis in human ovarian cancer

Angiogenesis is essential for both primary and metastatic tumor growth. Tumor blood vessel formation is complex and regulated by many factors. Ovarian carcinomas have a poor prognosis, often associated with multifocal intraperitoneal dissemination accompanied by intense neovascularization. To examine tumor angiogenesis in the tumor microenvironment, we studied malignant ascites of patients with untreated ovarian carcinoma. We observed high numbers of plasmacytoid dendritic cells (PDCs) and significant stromal-derived factor (CXCL-12/SDF)-1 in their malignant ascites, attracting PDCs into the tumor environment. We now show that tumor-associated PDCs induced angiogenesis in vivo through production of tumor necrosis factor alpha and interleukin 8. By contrast, myeloid dendritic cells (MDCs) were absent from malignant ascites. MDCs derived in vitro suppressed angiogenesis in vivo through production of interleukin 12. Thus, the tumor may attract PDCs to augment angiogenesis while excluding MDCs to prevent angiogenesis inhibition, demonstrating a novel mechanism for modulating tumor neovascularization. Because dendritic cells (DCs) have long been known to affect tumor immunity, our data also implicate DCs in regulation of tumor neoangiogenesis, suggesting a novel role of DCs in tumor pathology.

Peptides identified through phage display direct immunogenic antigen to dendritic cells

Dendritic cells (DC) play a critical role in adaptive immunity by presenting Ag, thereby priming naive T cells. Specific DC-binding peptides were identified using a phage display peptide library. DC-peptides were fused to hepatitis C virus nonstructural protein 3 (NS3) while preserving DC targeting selectivity and Ag immunogenicity. The NS3-DC-peptide fusion protein was efficiently presented to CD4+ and CD8+ T cells derived from hepatitis C virus-positive blood cells, inducing their activation and proliferation. This immunogenic fusion protein was significantly more potent than NS3 control fusion protein or NS3 alone. In chimeric NOD-SCID mice transplanted with human cells, DC-targeted NS3 primed naive CD4+ and CD8+ T cells for potent NS3-specific proliferation and cytokine secretion. The capacity of peptides to specifically target immunogenic Ags to DC may establish a novel strategy for vaccine development.

Specific recruitment of regulatory T cells in ovarian carcinoma fosters immune privilege and predicts reduced survival

Regulatory T (T(reg)) cells mediate homeostatic peripheral tolerance by suppressing autoreactive T cells. Failure of host antitumor immunity may be caused by exaggerated suppression of tumor-associated antigen-reactive lymphocytes mediated by T(reg) cells; however, definitive evidence that T(reg) cells have an immunopathological role in human cancer is lacking. Here we show, in detailed studies of CD4(+)CD25(+)FOXP3(+) T(reg) cells in 104 individuals affected with ovarian carcinoma, that human tumor T(reg) cells suppress tumor-specific T cell immunity and contribute to growth of human tumors in vivo. We also show that tumor T(reg) cells are associated with a high death hazard and reduced survival. Human T(reg) cells preferentially move to and accumulate in tumors and ascites, but rarely enter draining lymph nodes in later cancer stages. Tumor cells and microenvironmental macrophages produce the chemokine CCL22, which mediates trafficking of T(reg) cells to the tumor. This specific recruitment of T(reg) cells represents a mechanism by which tumors may foster immune privilege. Thus, blocking T(reg) cell migration or function may help to defeat human cancer.

Dendritic Cell Subsets Differentially Regulate Angiogenesis in Human Ovarian Cancer

Angiogenesis is essential for both primary and metastatic tumor growth. Tumor blood vessel formation is complex and regulated by many factors. Ovarian carcinomas have a poor prognosis, often associated with multifocal intraperitoneal dissemination accompanied by intense neovascularization. To examine tumor angiogenesis in the tumor microenvironment, we studied malignant ascites of patients with untreated ovarian carcinoma. We observed high numbers of plasmacytoid dendritic cells (PDCs) and significant stromal-derived factor (CXCL-12/SDF)-1 in their malignant ascites, attracting PDCs into the tumor environment. We now show that tumor-associated PDCs induced angiogenesis in vivo through production of tumor necrosis factor alpha and interleukin 8. By contrast, myeloid dendritic cells (MDCs) were absent from malignant ascites. MDCs derived in vitro suppressed angiogenesis in vivo through production of interleukin 12. Thus, the tumor may attract PDCs to augment angiogenesis while excluding MDCs to prevent angiogenesis inhibition, demonstrating a novel mechanism for modulating tumor neovascularization. Because dendritic cells (DCs) have long been known to affect tumor immunity, our data also implicate DCs in regulation of tumor neoangiogenesis, suggesting a novel role of DCs in tumor pathology.