AB0505 RISK OF SYSTEMIC LUPUS ERYTHEMATOSUS FLARES ACCORDING TO THE POSITIVITY OF AUTOANTIBODIES

Background

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by excessive production of pathogenic autoantibodies. A variety of autoantibodies can be detected in patients with SLE. Presence of particular autoantibody is known to be associated with specific manifestations of SLE: anti-double-stranded DNA antibody (anti-dsDNA Ab) with renal involvement and overall disease activity, anti-Sm Ab with renal involvement, anti-Ro Ab with cutaneous lupus and neonatal lupus, anti-La Ab with cutaneous lupus and neonatal lupus, and anti-U1RNP Ab with Raynaud’s phenomenon and pulmonary hypertension. However, little is known about the association between positivity of each autoantibody and risk of SLE flare.

Objectives

We aimed to assess the risk of SLE flare according to the positivity of various autoantibodies.

Methods

A total of 228 patients with SLE who fulfilled the 2012 Systemic Lupus International Collaborating Clinics (SLICC) classification criteria for SLE were included. SLE flare was defined as an increase of SLE disease activity index-2000 (SLEDAI-2K) of more than 4 points and/or hospitalization for SLE and/or augmentation of SLE therapy. The occurrence of flare was retrospectively reviewed from the date of SLE diagnosis to the date of last follow-up. Multivariable Cox regression analysis was conducted to estimate the hazard ratio (HR) and 95% confidence interval (CI) of SLE flare, according to the positivity of autoantibodies. Multivariable model was adjusted for sex, age at SLE diagnosis, positivity of other autoantibodies, SLEDAI-2K at diagnosis, use of immunosuppressants.

Results

Among the 228 patients, flare occurred in 179 (78.5 %) patients during 635.0 person-years of follow-up (incidence rate: 28.2/100 person-years). Of the 179 flares, 92 were severe flares (necessitating use of glucocorticoid dose > 20mg of prednisolone or equivalent, and/or addition of immunusuppressants), whereas 87 were mild-to-moderate flares (necessitating use of glucocorticoid dose < 20mg of prednisolone or equivalent, and no addition of immunosuppressants). In the multivariable Cox regression analysis, anti-dsDNA Ab positivity (adjusted HR 1.46, 95% CI 1.04–2.05, p = 0.031) and anti-Sm antibody positivity (adjusted HR 1.73, 95% CI 1.16–2.59, p = 0.007) were significantly associated with a higher risk of SLE flares.

Conclusion

Patients with SLE who are positive for anti-dsDNA Ab or anti-Sm Ab at diagnosis have a higher risk of SLE flare during the course of their disease. Careful monitoring of disease activity and prompt adjustment of therapy accordingly could be helpful in these patients.

References

Not applicable.

Table 1.

Risk of flares according to the positivity of each autoantibodies

Univariable analysisMultivariable analysisaUnadjusted HR (95% CI)P valueAdjusted HR (95% CI)P valueAnti-dsDNA antibody positivity1.47 (1.09–1.99)0.0111.46 (1.04–2.05)0.031Anti-Sm antibody positivity1.52 (1.12–2.07)0.0081.73 (1.16–2.59)0.007Anti-Ro antibody positivity1.19 (0.88–1.61)0.2521.04 (0.71–1.52)0.836Anti-La antibody positivity1.24 (0.89–1.74)0.2111.26 (0.83–1.92)0.278Anti-U1RNP antibody positivity1.19 (0.89–1.60)0.2500.83 (0.57–1.21)0.332

aAdjusted for sex, age at diagnosis, positivity of other autoantibodies, SLEDAI-2K at diagnosis, use of immunosuppressants

Acknowledgements

None.

Disclosure of Interests

None declared

FRI0281 NON-STEROIDAL ANTI-INFLAMMATORY DRUGS IN PATIENTS WITH STABLE ANKYLOSING SPONDYLITIS RECEIVING TUMOR NECROSIS FACTOR INHIBITOR: CONTINUED VS WITHDRAWN

Background:

A recent recommendation from the American College of Rheumatology/Spondylitis Association of America/Spondyloarthritis Research and Treatment Network (ACR/SAA/SPARTAN) suggests withdrawing non-steroidal anti-inflammatory drugs (NSAIDs) in patients with stable ankylosing spondylitis (AS) receiving tumor necrosis factor inhibitor (TNFi) and NSAIDs.1However, the level of evidence for this statement is very low with lack of evidence supporting this recommendation. No studies have directly compared stable AS patients receiving TNFi with NSAIDs, and those receiving TNFi without NSAIDs.

Objectives:

To compare the disease activity in stable AS patients receiving TNFi, according to the use of NSAIDs.

Methods:

In total, 189 patients with stable AS receiving TNFi were included. Patients were classified into NSAID withdrawn group (n=48) and NSAID continued group (n=141), according to the use of NSAIDs. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were measured every 3 months, and Bath ankylosing spondylitis disease activity index (BASDAI) was measured every 6 months as parameters to evaluate disease activity. ESR, CRP, and BASDAI at each time point, and time-averaged values of each parameter during the observation period of one-year were compared between the two groups. Repeated-measure ANOVA was performed to compare changes in disease activity parameters during the observation period between the two groups.

Table .

Disease activity measures during observation period

NSAID withdrawn(N = 48)NSAID continued(N = 141)P valueAt 3 months ESR (mm/hr), median (IQR)5.0 (2.0–14.0)7.0 (2.0–15.0)0.712 CRP (mg/L), median (IQR)0.5 (0.2–1.5)0.8 (0.3–1.8)0.613At 6 months ESR (mm/hr), median (IQR)5.0 (2.0–15.0)7.0 (2.0–15.0)0.278 CRP (mg/L), median (IQR)0.6 (0.3–1.8)0.8 (0.3–2.1)0.335 BASDAI, mean ± SD2.019 ± 0.5692.226 ± 1.0280.187At 9 months ESR (mm/hr), median (IQR)4.5 (2.0–13.8)7.0 (2.8–17.0)0.261 CRP (mg/L), median (IQR)0.5 (0.3–1.6)0.8 (0.3–2.2)0.129At 12 months ESR (mm/hr), median (IQR)6.0 (2.0–13.0)9.0 (3.0–19.0)0.050 CRP (mg/L), median (IQR)0.6 (0.3–2.1)1.0 (0.4–3.1)0.151 BASDAI, mean ± SD2.168 ± 1.0662.197 ± 1.0020.867Time-averaged values ESR (mm/hr), median (IQR)5.3 (2.6–15.2)8.4 (3.8–14.7)0.096 CRP (mg/L), median (IQR)0.8 (0.4–1.8)1.1 (0.5–2.9)0.136 BASDAI, mean ± SD2.137 ± 0.5572.227 ± 0.7060.421

Abbreviations: NSAIDs, non-steroidal anti-inflammatory drugs; ESR, erythrocyte sedimentation rate; CRP, C-reactive protein; BASDAI, Bath ankylosing spondylitis disease activity index.

Results:

The level of ESR, CRP, and BASDAI at baseline and during the observation period did not differ between the two groups. The time-averaged values of ESR (p=0.096), CRP (p=0.136), and BASDAI (p=0.421), and changes of ESR (p=0.101), CRP (p=0.714), and BASDAI (p=0.613) during the observation period were not significantly different between the two groups.

Conclusion:

The continued use of NSAIDs in patients with stable AS receiving TNFi had no additional benefit in controlling the disease activity, as compared to patients who withdrew NSAIDs. Considering the risk of toxicity of long-term NSAID use, withdrawal of NSAIDs in stable AS patients receiving TNFi may be preferable.

References:

[1]Ward MM, Deodhar A, Gensler LS, et al.2019 Update of the American College of Rheumatology/Spondylitis Association of America/Spondyloarthritis Research and Treatment Network Recommendations for the Treatment of Ankylosing Spondylitis and Nonradiographic Axial Spondyloarthritis.Arthritis Rheumatol2019;71:1599-613 doi: 10.1002/art.41042.

Acknowledgments:

None.

Disclosure of Interests:

None declared

THU0274 RENAL CHARACTERISTICS AND OUTCOME OF LUPUS NEPHRITIS ACCORDING TO ITS TIME OF ONSET

Background:

Lupus nephritis (LN) usually develops within 5 years of systemic lupus erythematosus (SLE) onset. It is unclear whether the course and outcome of LN differ between patients who initially had LN at SLE onset (initial-onset LN) and those who developed LN within 5 years after SLE onset (early-onset LN).

Objectives:

To compare clinical characteristics and renal outcomes between SLE patients with initial-onset LN and SLE patients with early-onset LN.

Methods:

SLE patients with biopsy-proven LN were retrospectively reviewed. The clinical parameters and renal outcomes were compared between initial-onset LN and early-onset LN groups. We used Cox regression analysis to estimate risk of worse renal outcome, according to the onset time of LN.

Results:

Of the total 136 LN patients, 92 (67.6%) and 44 (32.4%) patients were classified into the initial-onset and early-onset LN groups, respectively. The initial-onset LN group had higher prevalences of impaired renal function (34.8% vs. 11.4%, p=0.004) and microscopic hematuria (73.9% vs. 54.5%, p=0.024), and higher urine protein/creatinine ratio (4626.1 [2180.0–6788.3] vs. 2410.0 [1265.0–5168.5] mg/g, p=0.006) at LN diagnosis. Renal relapse (46.3% vs 25.7%, p=0.039) and progression to chronic kidney disease (CKD) or end-stage renal disease (ESRD) were more common (24.4% vs. 8.3%, p=0.042) in the initial-onset LN group. In the multivariable Cox regression analysis, initial-onset LN group had higher risk of renal relapse (adjusted hazard ratio [HR] 2.938, 95% confidence interval [95% CI] 1.344–6.426, p=0.007) and progression to CKD or ESRD (adjusted HR 4.642, 95% CI 1.107–19.458, p=0.036), compared with early-onset LN group.

Conclusion:

Patients with LN at SLE onset may have more severe renal presentations and worse renal outcome than those who develop LN within 5 years.

References:

Not applicable

Table.

Hazard ratios for renal relapse and progression to CKD/ESRD according to onset time of LN

Univariable analysisMultivariable analysisaHR (95% CI)pHR (95% CI)pRenal relapseEarly-onset LN1.000 (reference)1.000 (reference)Initial-onset LN2.734 (1.315–5.686)0.0072.938 (1.344–6.426)0.007Progression to CKD/ESRDEarly-onset LN1.000 (reference)1.000 (reference)Initial-onset LN4.201 (1.249–14.132)0.0204.642 (1.107–19.458)0.036

aAdjusted for age, ISN/RPS class, activity index, chronicity index, GFR, UPCR, hematuria and use of HCQ

LN, lupus nephritis; CKD, chronic kidney disease; ESRD, end-stage renal disease; ISN/RPS, International Society of Nephrology/Renal Pathology Society (ISN/RPS); GFR, glomerular filtration rate; UPCR, urine protein/creatinine ratio; HCQ, hydroxychloroquine; HR, hazard ratio; CI, confidence interval

Acknowledgments:

None.

Disclosure of Interests:

None declared

FRI0176 NON-HISTOLOGIC FACTORS DISCRIMINATING PROLIFERATIVE LUPUS NEPHRITIS FROM MEMBRANOUS LUPUS NEPHRITIS

Background:

The treatment strategy and renal prognosis between proliferative lupus nephritis (LN) and membranous LN are different. Therefore, it is important to distinguish one from the other. To date, data regarding non-histologic factors that can discriminate proliferative LN from membranous LN are limited.

Objectives:

To investigate non-histologic factors that can discriminate proliferative LN from membranous LN in patients with systemic lupus erythematosus with renal manifestations.

Methods:

Patients with biopsy-proven proliferative LN and membranous LN were included. Non-histologic factors were compared between the two groups. A logistic regression analysis was performed to identify the factors associated with proliferative LN. To assess the accuracy of these factors in discriminating between proliferative LN and membranous LN, we performed a receiver-operating characteristic analysis.

Results:

Of the total 168 patients with biopsy-proven LN, 150 patients (89.3%) had proliferative LN, and 18 patients (10.7%) had membranous LN. In the multivariable logistic regression analysis, positive anti-double-stranded DNA (anti-dsDNA) antibody (adjusted OR = 11.200, 95% CI = 2.202–56.957, p = 0.004) was associated with proliferative LN, while positive anti-U1RNP antibody (adjusted OR = 0.176, 95% CI = 0.040–0.769, p = 0.021) and higher glomerular filtration rate (GFR) (adjusted OR = 0.973, 95% CI = 0.951–0.994, p = 0.013) were inversely associated with proliferative LN. Among these covariates, the anti-dsDNA antibody (area under the curve = 0.806, 95% CI = 0.695–0.916) had the highest accuracy in discriminating between proliferative LN and membranous LN.

Conclusion:

The positivity of anti-dsDNA antibody was associated with proliferative LN, while the positivity of anti-U1RNP antibody and GFR were inversely associated with proliferative LN. The anti-dsDNA antibody had a good accuracy in discriminating proliferative LN from membranous LN.

References:

Not applicable

Table.

Factors associated with proliferative LN

Univariable analysisMultivariable analysisOR (95% CI)pOR (95% CI)pAge0.982 (0.951–1.014)0.269Female sex1.437 (0.295–7.006)0.653Positive anti-Sm Ab0.648 (0.243–1.728)0.386Positive anti-Ro Ab0.928 (0.341–2.529)0.885Positive anti-La Ab2.075 (0.572–7.528)0.267Positive anti-U1RNP Aba0.271 (0.085–0.861)0.0270.176 (0.040–0.769)0.021Positive anti-dsDNA Aba7.333 (2.574–20.893)<0.00111.200 (2.202–56.957)0.004Low C3a9.970 (3.117–31.891)<0.0011.886 (0.255–13.932)0.534Low C4a3.839 (1.405–10.486)0.0091.224 (0.229–6.552)0.813GFR0.980 (0.964–0.997)0.0210.973 (0.951–0.994)0.013Urine PCR1.000 (0.987–1.013)0.986Urine RBC of ≥ 5/HPF4.178 (1.516–11.509)0.0062.053 (0.426–9.893)0.370Urine WBC of ≥ 5/HPF2.687 (0.958–7.543)0.060Urine cast4.429 (0.567–34.578)0.156SLEDAI-2K1.173 (1.063–1.294)0.0011.046 (0.900–1.216)0.557

Variables with P value less than 0.05 in the univariable analysis were selected for inclusion in the multivariable analysis.

aAnalyzed as binary variables (Anti-U1RNP Ab, positive/negative; Anti-dsDNA Ab, positive/negative; C3, low/not low; C4, low/not low)

Ab, antibody; anti-dsDNA, anti-double-stranded DNA; GFR, glomerular filtration rate; PCR, protein/creatinine ratio; RBC, red blood cell; HPF, high power field; WBC, white blood cell; SLEDAI-2K, Systemic Lupus Erythematosus Disease Activity Index 2000; OR, odds ratio; CI, confidence interval

Acknowledgments:

None.

Disclosure of Interests:

None declared

Flow cytometric analysis and chromosome sorting of barley (hordeum vulgare L)

Flow cytometric analysis was systematically performed to optimize the concentration and duration of hydroxyurea (DNA synthesis inhibitor) and trifluralin (metaphase blocking reagent) treatments for synchronizing the cell cycle and accumulating metaphase chromosomes in barley root tips. A high metaphase index (76.5% in the root tip meristematic area) was routinely achieved. Seedlings of about 1.0-cm length were treated with 1.25 mM hydroxyurea for 14 h to synchronize the root tip meristem cells at the S/G2 phase. After rinsing with hydroxyurea, the seedlings were incubated in a hydroxyurea-free solution for 2 h and were treated with 1 microM trifluralin for 4 h to accumulate mitotic cells in the metaphase. The consistent high metaphase index depended on the uniform germination of seeds prior to treatment. High-quality and high-quantity isolated metaphase chromosomes were suitable for flow cytometric analysis and sorting. Flow karyotypes of barley chromosomes were established via univariate and bivariate analysis. A variation of flow karyotypes was detected among barley lines. Two single chromosome types were identified and sorted. Bivariate analysis showed no variation among barley individual chromosomes in AT and GC content.

Distribution of nitric oxide in the nasal mucosa of the rat: a histochemical study

We evaluated the distribution of nitric oxide (NO) in the rat nasal mucosa using nicotineamide adenosine dinucleotide phosphate (NADPH)-diaphorase histochemistry. The NADPH-diaphorase positive nerve fibers in the nasal mucosa were observed around blood vessels and submucosal glands and in sphenopalatine ganglions. Strong positive reactions for NADPH-diaphorase were observed in ganglions as compared with the other tissues. In septal and turbinate mucosa, positive reactions for NADPH-diaphorase were mainly seen in the anterior portion, and a few positive reactions were observed in the posterior portion. No positive reactions for NADPH-diaphorase were demonstrated in the sinus mucosa. These results suggest that NO may be related to regulation of blood flow, glandular secretion and neurotransmission, and also that NO may play an important role in the defense mechanism of the upper airway system against external environments.

Immunoelectron microscopy of corticotropes and melanotropes in the pituitary gland of the European ferret, Mustela putorius furo

The superimposition technique and protein A-gold method of immunoelectron microscopy were employed to study the ultrastructure of corticotropes as well as melanotropes in the ferret pituitary gland. This is the first study ever elucidating the ultrastructural heterogeneity of melanotropes in mammalian pars intermedia on an immunocytochemical basis. Morphological heterogeneity of pars distalis corticotropes has also been elucidated. It is suggested that the different subtypes may represent stages of development (histogenesis), or functional phases of a single cell type. In addition, the occurrence and distribution of both corticotropes and melanotropes in different hypophyseal components have been studied by light-microscopic immunocytochemistry.

Regeneration of plantlets from petiole callus of wild viola (Viola patrinii DC.)

Plantlets were regenerated from 5-year subcultured compact callus derived from petiole tissues of wild viola (Viola patrinii DC.) but not from 5-year subcultured friable callus. Regeneration occurred most efficiently on medium that contained two-fold diluted basal salts of Murashige and Skoog's (MS) medium, 5 × 10(-6) M 1-naphthaleneacetic acid and 10(-6) M kinetin. The effect of dilution of MS basal salts could also be achieved solely by two-fold dilution of the potassium dihydrogen phosphate in the mixture.The present study revealed that dilution of MS basal salts, in particular of potassium dihydrogen phosphate, was important for the regeneration of wild viola. Moreover, although the callus had been subcultured for 5 years, regeneration of plantlets from callus was still possible. In addition, scanning electron microscopy revealed that details of the process of plant regeneration from subcultured callus varied with the age and source of callus and differed from that reported in rice.

MHC class I gene(s) in the D/L region but not the TNF-alpha gene determines development of toxoplasmic encephalitis in mice

Previous studies revealed that mice with the b or k allele at the H-2D region are susceptible to toxoplasmic encephalitis (TE); those with the d allele are resistant. To determine whether the b or d allele is dominant, F1 hybrids between susceptible C57BL/6 (H-2b) and resistant BALB/c (H-2d) mice were infected with T. gondii. TE was not observed in the F1 hybrids, indicating that the d allele is dominant for protection against development of TE. Mice with a mutation in the D/L region were used to determine whether the D gene or the L gene of MHC class I Ags of the H-2D region is most critical for resistance against development of TE. B10.D2-H2dm1 (dm1) mice that have the mutant D/L hybrid gene formed by fusion of the 5' part of the Dd gene and the 3' part of the Ld gene developed TE in contrast to their background B10.D2 mice. BALB/c-H-2dm2 (dm2) mice, which have a complete deletion of the Ld gene, had significantly more T. gondii cysts in their brains than did dm1 mice and developed large areas of necrosis in their brains that were not observed in dm1 mice. These results indicate that a gene(s) in the D/L region determines whether TE will occur and that the Ld gene plays a critical role in the resistance against development of TE. Polymorphisms in the TNF-alpha gene (located in the H-2D region) have been reported to correlate with resistance against the development of TE. When development of TE was studied in BALB/c and dm2 mice that have the same TNF-alpha gene, only dm2 mice developed TE. This indicates that the TNF-alpha gene is not a determining factor for the development of TE. Transcripts for TNF-alpha were detected in brains of infected dm2 mice but not in BALB/c mice. Injection of neutralizing Abs against TNF-alpha resulted in worsening of the TE in infected dm2 mice but did not induce TE in infected BALB/c mice. Thus, TNF-alpha appears to be produced in the brain after TE has developed and is responsible for preventing the progression of TE.

MHC class I gene(s) in the D/L region but not the TNF-alpha gene determines development of toxoplasmic encephalitis in mice

Previous studies revealed that mice with the b or k allele at the H-2D region are susceptible to toxoplasmic encephalitis (TE); those with the d allele are resistant. To determine whether the b or d allele is dominant, F1 hybrids between susceptible C57BL/6 (H-2b) and resistant BALB/c (H-2d) mice were infected with T. gondii. TE was not observed in the F1 hybrids, indicating that the d allele is dominant for protection against development of TE. Mice with a mutation in the D/L region were used to determine whether the D gene or the L gene of MHC class I Ags of the H-2D region is most critical for resistance against development of TE. B10.D2-H2dm1 (dm1) mice that have the mutant D/L hybrid gene formed by fusion of the 5' part of the Dd gene and the 3' part of the Ld gene developed TE in contrast to their background B10.D2 mice. BALB/c-H-2dm2 (dm2) mice, which have a complete deletion of the Ld gene, had significantly more T. gondii cysts in their brains than did dm1 mice and developed large areas of necrosis in their brains that were not observed in dm1 mice. These results indicate that a gene(s) in the D/L region determines whether TE will occur and that the Ld gene plays a critical role in the resistance against development of TE. Polymorphisms in the TNF-alpha gene (located in the H-2D region) have been reported to correlate with resistance against the development of TE. When development of TE was studied in BALB/c and dm2 mice that have the same TNF-alpha gene, only dm2 mice developed TE. This indicates that the TNF-alpha gene is not a determining factor for the development of TE. Transcripts for TNF-alpha were detected in brains of infected dm2 mice but not in BALB/c mice. Injection of neutralizing Abs against TNF-alpha resulted in worsening of the TE in infected dm2 mice but did not induce TE in infected BALB/c mice. Thus, TNF-alpha appears to be produced in the brain after TE has developed and is responsible for preventing the progression of TE.

Immunoelectron microscopic study of the GH cell in the anterior pituitary gland of normal human fetus

BACKGROUND

Ultrastructural studies of growth hormone-producing cells (GH cells) in the anterior pituitary gland have been reported using several experimental animals. However, no attempt has yet been made to identify the ultrastructural heterogeneity of the GH cells within the human anterior pituitary gland. To this end, we employed immunogold electron microscopy to investigate the ultrastructural characteristics of GH cells in relation to gestational age in normal human fetuses.

MATERIALS

Based on ultrastructural characteristics, three distinct types of GH cells were identified by immunogold electron microscopy in the anterior pituitary glands of 34 normal human fetal pituitary glands. The age of the tissue samples ranged from 8 to 34 weeks.

RESULTS

The Type-I GH cell is a small, round cell with a narrow cytoplasm containing a few small secretory granules (268 nm in mean diameter). The GH cells designated Type-II are polygonal and contain medium-sized secretory granules (347 nm), profiles of rough endoplasmic reticulum (RER) arranged in parallel lamellae, and a Golgi complex which is frequently encountered but only in this cell type. The Type-III GH cell is polygonal, large, and contains numerous large spherical-shaped secretory granules (404 nm). The Type-I was the predominant cell type until about 20 weeks of gestation; its incidence decreased thereafter. In contrast, the Type-II and Type-III cells increased in number starting at 20 weeks of gestational age.

CONCLUSION

From these results, we suggest that Type-I is the most immature type of GH cell, Type-III the most mature, and the Type-II is intermediate in development. The marked difference in the incidence of each GH cell type between the first and second half of gestation appears to be a reflection of the development of the hypothalamic regulation of the anterior pituitary gland, which is reported to be established at around 20 weeks of gestation.