Ro 0437626

Anti-La positive, anti-Ro negative subset of primary Sjogren's syndrome: anti-La is a reality but is the disease?[Pubmed:28229827]

Clin Exp Rheumatol. 2017 May-Jun;35(3):438-444. Epub 2017 Feb 20.

OBJECTIVES: To characterise the serological and clinical findings in primary Sjogren's syndrome in which anti-La was found without anti-Ro. We hypothesised that a significant portion of these are falsely negative for anti-Ro60. METHODS: Twenty-nine sera from primary Sjogren's syndrome patients were tested for antibodies directed against La and Ro. Anti-La was detected using bovine La treated with or without DNAase and RNAase to identify potential false positivity. Anti-Ro60 antibodies were detected using HEp-2000 substrate (in which cells are transfected with human Ro60) and HEp-2 substrate. Anti-Ro60 and Ro-52 were also tested by in vitro transcription/translation followed by immunoprecipitation assay. RESULTS: All 29 sera bound La, even after treatment with DNAase and RNAase. Of the 29 sera, 25 were unequivocally negative on HEp-2000 (1:40 dilution). Four samples were anti-Ro60 positive with a speckled pattern, three of the four at 1:320 dilution. Thus, false negative anti-Ro60 exists in a small fraction (14%) of the Ro-negative/La-positive primary Sjogren's patients. However, all the samples were negative for Ro60 and Ro52 by in vitro immunoprecipitation assay. Clinically these patients tended not to have salivary gland pathology characteristic of Sjogren's syndrome. CONCLUSIONS: We found only a small fraction of Ro negative/La positive sera to show positive HEp-2000 pattern. These subjects did not have characteristic findings on pathological examination of minor salivary glands, suggesting these subjects have a process distinct from Sjogren's syndrome.

Spontaneous Remission of Congenital Complete Atrioventricular Block in Anti-Ro/La Antibody-Negative Monozygotic Twins: Case Report.[Pubmed:28251027]

Balkan Med J. 2017 Jan;34(1):71-73.

BACKGROUND: Congenital complete atrioventricular block without any structural heart disease and anti-Ro/La negativity is very rare. Discordant complete atrioventricular block, which is more frequently defined in the literature as an autoimmune mechanism, is much more rare in monozygotic twins. CASE REPORT: The 26-year-old healthy mother had given birth in her first spontaneous, uneventful pregnancy to monozygotic twins at week 35. While the first twin's physical examination proved her to be normal with a pulse rate consistent with her age, the second twin had a pulse rate of approximately 40 beats/minute.The patient was confirmed to have congenital complete atrioventricular block. CONCLUSION: Despite this case appears to be an isolated one, a discordant complete atrioventricular block regression without any autoimmune evidence should be included in the differential diagnosis of bradycardia in infants.

Low titer, isolated anti Ro/SSA 60 kd antibodies is correlated with positive pregnancy outcomes in women at risk of congenital heart block.[Pubmed:28204891]

Clin Rheumatol. 2017 May;36(5):1155-1160.

Congenital heart block (CHB) is an autoantibody mediated disorder presumably caused by placental transmission of maternal autoantibodies to Ro/SSA 52 kd, p200, Ro/SSA 60 kd, La/SSB ribonucleoproteins. This study investigated the clinical significance of isolated anti-Ro/SSA 52 kd, anti-p200, anti-Ro/SSA 60 kd, and anti-La/SSB antibodies in positive pregnant patients. One hundred sixty-three pregnant women positive to anti-Ro/SSA 52 kd and/or anti-Ro/SSA 60 kd and/or anti-La/SSB antibodies were prospectively enrolled in the study. Anti-Ro52, anti-Ro60, anti-p200, and anti-La antibodies were assayed using home-made ELISA assays. Isolated antibody positivity was found in 25 women (15.3%), while multiple antibody positivity in 138 (84.7%). Twenty-four developed CHB, and the 139 had a favorable pregnancy outcome. The prevalence of isolated anti-Ro/SSA 60 kd antibodies was significantly higher (p < 0.046) as the prevalence of lower mean antibody titers (p < 0.0001) in the later group. Confirmation of these results by large-scale studies could lead clinicians to recommend less stringent fetal echocardiography monitoring in women with isolated anti-Ro/SSA 60 kd antibodies.

Neonatal lupus: Follow-up in infants with anti-SSA/Ro antibodies and review of the literature.[Pubmed:28212920]

Autoimmun Rev. 2017 Apr;16(4):427-432.

Neonatal Lupus Syndrome (NLS) is a distinct clinical entity caused by transplacental passage of maternal anti-SSA/Ro antibodies (Ab). Mothers may have systemic lupus erythematosus, Sjogren syndrome, or other connective tissue disease, or may be completely healthy at the time of giving birth. NLS includes several clinical manifestations: complete congenital heart block (CCHB) and cutaneous lupus are the most common, while hepatobiliary disease, hematological manifestations and central nervous system involvement may occur. Data from literature on the incidence of the different clinical manifestations of NLS are difficult to compare because they come mostly from retrospective studies or prospective studies, but up to date no systematic follow-up was carried out. We performed a large prospective single-center study with a systematic clinical and instrumental follow-up until 9months of life, in order to evaluate the incidence and the clinical impact of NLS features. From 2004 to 2014 all infants born in our center to mothers with anti-SSA/Ro Ab were enrolled in a specific diagnostic and follow-up (FU) program. At birth, 50 infants born to mothers with anti-SSA/Ro Ab were found positive for anti-SSA/Ro Ab. Infants were tested for anti SSA/Ro Ab at 3months of life, if positive they were re-tested at 6 and 9months. At 9months anti-SSA/Ro Ab were positive in 10% of children. In two cases (4%) a CCHB was identified during pregnancy and required pacemaker implantation at birth. In 10% of cases a transient ECG alterations was found during follow-up. Hematological NLS features (anemia, neutropenia, thrombocytopenia) were found at birth and during FU in several patients, in all cases without clinical manifestations and in most cases with complete normalization at 9months. Mild and transient elevation of aminotransferases between 3 and 6months of life were found in 56% and 40% of patient, respectively; non-specific ultrasound cerebral anomalies in absence of clinical neurological signs were found at birth in 9 patients (18%), subsequently normalized. Prenatal maternal screening is of primary importance in order to early detect CCHB, which requires maternal treatment and pacemaker implantation at birth. Infants born to mothers with anti-SSA/Ro Ab should be monitored for all NLS features at birth. However, during the first months of life, these infants seem to develop only mild, transient and self-limited clinical manifestations, which in most cases are completely solved at 9months of life. This consideration, together with the evidence that only 10% of infants had anti-SSA/Ro Ab persistent in blood at 9months, suggests that follow-up of these children can be performed until 6-9months of life with good clinical safety. Moreover, a clinical and laboratory monitoring at 3months of life, when the highest incidence of hematological features and liver tests alterations are observed, is strongly recommended. In the future, it would be clarified if a follow-up until adulthood would be indicated in cases with persistent anti SSA/Ro or in all infants born to mother with anti SSA/Ro.

Purinoceptors as therapeutic targets for lower urinary tract dysfunction.[Pubmed:16465177]

Br J Pharmacol. 2006 Feb;147 Suppl 2:S132-43.

Lower urinary tract symptoms (LUTS) are present in many common urological syndromes. However, their current suboptimal management by muscarinic and alpha(1)-adrenoceptor antagonists leaves a significant opportunity for the discovery and development of superior medicines. As potential targets for such therapeutics, purinoceptors have emerged over the last two decades from investigations that have established a prominent role for ATP in the regulation of urinary bladder function under normal and pathophysiological conditions. In particular, evidence suggests that ATP signaling via P2X(1) receptors participates in the efferent control of detrusor smooth muscle excitability, and that this function may be heightened in disease and aging. ATP also appears to be involved in bladder sensation, via activation of P2X(3) and P2X(2/3) receptors on sensory afferent neurons, both within the bladder itself and possibly at central synapses. Such findings are based on results from classical pharmacological and localization studies in non-human and human tissues, knockout mice, and studies using recently identified pharmacological antagonists--some of which possess attributes that offer the potential for optimization into candidate drug molecules. Based on recent advances in this field, it is clearly possible that the development of selective antagonists for these receptors will occur that could lead to therapies offering better relief of sensory and motor symptoms for patients, while minimizing the systemic side effects that limit current medicines.

Discovery and synthesis of a novel and selective drug-like P2X(1) antagonist.[Pubmed:15927468]

Bioorg Med Chem Lett. 2005 Jul 1;15(13):3292-5.

Although there is extensive literature to indicate that many different types of P2 purinoceptors are present in the lower urinary tract, the physiological role of these receptors in micturition is still uncertain. In part, this uncertainty has been caused by a lack of P2 subtype selective ligands. In this paper we report the discovery, gram scale synthesis, and binding results for 1, the first potent, drug-like, selective P2X(1) receptor antagonist described. Compound 1 was shown to be more than 30-fold selective over other purinergic receptor subtypes.

Investigation of the effects of P2 purinoceptor ligands on the micturition reflex in female urethane-anaesthetized rats.[Pubmed:15148261]

Br J Pharmacol. 2004 Jun;142(3):519-30.

1 The effects of purinoceptor ligands for P2X1 and/or P2X3 receptors (alpha,beta-meATP, IP(5)I, TNP-ATP, MRS 2179, PPADS, Phenol red and RO116-6446/008; i.v., n=4-5) and for P2Y1 receptors (PPADS, MRS 2179 and MRS 2269; i.v., n=3-5) were investigated on the distension-evoked 'micturition reflex' in the urethane-anaesthetized female rat. 2 Alpha,beta-meATP (180 nmol kg(-1) min(-1)), IP5I (10, 30 and 100 nmol kg(-1)), TNP-ATP (1 micromol kg(-1)), MRS 2179 (1 micromol kg(-1)) and PPADS (17 micromol kg(-1)) each caused maintained bladder contractions to occur during the infusion of saline into the bladder. PPADS (17 micromol kg(-1) min(-1)) had a similar effect when infused intravesicularly. Regular bladder contractions were not observed until the infusion of saline was halted. For IP5I, TNP-ATP, MRS 2179 and PPADS, the magnitude of postinfusion isovolumetric contractions was significantly reduced and, for IP5I, this action was also associated with a significant reduction in urethral relaxation. Additionally, TNP-ATP caused a significant increase in the pressure and volume thresholds required to initiate a reflex. 3 Phenol red (a P2X1/P2X3 antagonist; 0.1 and 1 micromol kg(-1)) caused a significant increase in the pressure and volume thresholds required to initiate a reflex and, at the higher dose, also caused a reduction in postinfusion isovolumetric contractions. 4 RO116-6446/008 (a P2X1-selective antagonist; 1 and 10 micromol kg(-1)) only caused a reduction in postinfusion isovolumetric contractions. 5 It is concluded that P2X1 and P2X3 receptors play a fundamental role in the micturition reflex in urethane-anesthetized female rats. P2X3 receptor blockade raised the pressure and volume thresholds for the reflex, whereas P2X1 receptor blockade diminished motor activity associated with voiding. P2Y1 receptors may be involved in inhibition of rat detrusor tone.