Comparison of clinical characteristics in patients with Vogt-Koyanagi-Harada disease with and without anti-retinal antibodies.

PURPOSE: To compare the clinical characteristics of Vogt-Koyanagi-Harada (VKH) disease patients with and without anti-retinal antibodies (ARAs) that are frequently detected in autoimmune retinopathy. METHODS: Using immunoblot analyses, serum autoantibodies for recoverin, carbonic anhydrase II, and α-enolase were examined in 20 treatment-naïve patients with VKH disease. Clinical factors before and after systemic corticosteroid therapy, including best-corrected visual acuity (BCVA) and macular outer retinal morphology, were statistically compared between patients with VKH disease with and without ARAs. RESULTS: Serum ARAs were detected in 50.0% of patients with VKH disease. There were no significant differences in clinical factors between the two groups, including final BCVA, frequency of uveitis recurrence, and recovery of the macular ellipsoid zone after systemic corticosteroid therapy. CONCLUSIONS: Our results suggest that the detected ARAs did not influence visual outcomes, the chronicity of uveitis, or outer retinal morphology in patients with VKH disease.

Detection of serum anti-retinal antibodies in the Chinese patients with presumed autoimmune retinopathy.

PURPOSE: To explore the presence of serum anti-retinal antibodies (ARAs) in the Chinese patients with presumed autoimmune retinopathy (AIR). METHODS: Twenty-three Chinese patients with presumed AIR, disease controls including 40 RP patients, 22 bilateral uveitis patients, 18 acute zonal outer occult retinopathy (AZOOR) patients, and 30 healthy donors were included. Serum samples of all the subjects were obtained and analyzed for the presence of four ARAs including recoverin, α-enolase, carbonic anhydraseII (CAII), and collapsin response-mediated protein (CRMP)-5 by Western bolt assay. RESULTS: ARAs were present in the serum of either presumed AIR patients, disease control, or healthy donors. One or more ARAs were present in the 78.2% of presumed AIR while they were indicated in the 35.0% of RP patients (p < 0.01) and 33.3% of healthy donors (p < 0.01). The prevalence of ARAs in the bilateral uveitis and AZOOR was 63.3% and 100% respectively. Positive rate of α-enolase antibody present in the presumed AIR, disease control, and healthy donors was 73.9%, 47.5%, and 33.3% respectively. Positive rate of CAII antibody present above groups was 52.1%, 50%, and 33.3% respectively. Recoverin antibody seemed to be specifically present in the serum of patients with cancer-associated retinopathy. CONCLUSION: Presence of serum ARAs including recoverin, α-enolase, CAII, or CRMP-5 in the Chinese patients with presumed AIR occurred significantly more often than RP patients and healthy donors. Seropositivity of ARAs had diagnostic value for the presumed AIR but mere presence was not sufficient for the diagnosis due to identification of them in the healthy controls and other retinal diseases.

Clinical Features of Japanese Patients With Anti-α-enolase Antibody-Positive Autoimmune Retinopathy: Novel Subtype of Multiple Drusen.

PURPOSE: To evaluate clinical features of Japanese patients with anti-α-enolase antibody-positive autoimmune retinopathy (anti-enolase AIR). DESIGN: Multicenter retrospective observational case series. METHODS: Forty-nine eyes of 25 Japanese anti-enolase AIR patients (16 female and 9 male; mean age at first visit, 60.8 years) were included. Fundus characteristics, perimetry, spectral-domain optical coherence tomography (SD-OCT), electroretinography (ERG), best-corrected visual acuity (BCVA), and complicating systemic tumors were assessed. Protein localization of α-enolase was examined by immunohistochemistry in an enucleated eye of 1 patient. RESULTS: Patients were classified into 3 groups: multiple drusen (48%), retinal degeneration (36%), and normal fundus (16%). Drusen varied in size from small deposits to vitelliform-like lesions. Images on SD-OCT revealed dome-shaped hyperreflectivity beneath the retinal pigment epithelium (RPE), corresponding to drusen. Perimetry showed that ring scotoma was the most frequent (39%). Rod-system and/or single-flash cone responses revealed decreased responses in 81% of the eyes. Combined rod and cone system responses demonstrated significantly lower a-wave amplitudes in the degeneration group than in the drusen group (P = .005). BCVA was improved or maintained in 80% of the eyes during follow-up. Malignant or benign tumors were detected in 30% of patients. The RPE and photoreceptor layers were immunopositive for α-enolase. CONCLUSIONS: The drusen subtype, scarcely described in the literature, is suggested to characterize Japanese patients with anti-enolase AIR. The different funduscopic features with different functional severities may have resulted from antibody-mediated damage to RPE as well as photoreceptor cells.

Autoantibodies Against Carbonic Anhydrase I and II in Patients with Acute Myeloid Leukemia.

OBJECTIVE: Cancer, one of the principal causes of death, is a global social health problem. Autoantibodies developed against the organism's self-antigens are detected in the sera of subjects with cancer. In recent years carbonic anhydrase (CA) I and II autoantibodies have been shown in some autoimmune diseases and carcinomas, but the mechanisms underlying this immune response have not yet been explained. The aim of this study was to evaluate CA I and II autoantibodies in patients with acute myeloid leukemia (AML) and to provide a novel perspective regarding the autoimmune basis of the disease. MATERIALS AND METHODS: Anti-CA I and II antibody levels were investigated using ELISA in serum samples from 30 patients with AML and 30 healthy peers. RESULTS: Anti-CA I and II antibody titers in the AML group were significantly higher compared with the control group (p=0.0001 and 0.018, respectively). A strong positive correlation was also determined between titers of anti-CA I and II antibodies (r=0.613, p=0.0001). CONCLUSION: Our results suggest that these autoantibodies may be involved in the pathogenesis of AML. More extensive studies are now needed to reveal the entire mechanism.

Unique epitopes for carbonic anhydrase II autoantibodies related to autoimmune retinopathy and cancer-associated retinopathy.

High titers of anti-carbonic anhydrase II (anti-CA II) autoantibodies were detected in sera of patients with autoimmune retinopathies (AR), including cancer-associated retinopathy (CAR) and also in normal population. The goal was to investigate whether unique immunodominant epitopes for anti-CAII autoantibodies occur in AR and CAR. A cohort of 216 patients with symptoms of AR and CAR and healthy controls, seropositive for anti-CA II autoantibodies were analyzed for the prevalence of CAII major domains. Autoantibody titers against CAII in sera were determined by ELISA. Biotinylated 12-mer synthetic peptides, overlapping the entire sequence of CAII, were coated onto a microplate and monospecific sera were tested for their ability to bind specific peptides by ELISA. We identified 3 epitopes common for AR, CAR and control subjects but the key epitopes were significantly different between sera from different groups (p = 0.009). Ninety one percent of AR sera predominantly reacted with the N-terminal epitope 85-90 (p < 0.0001), which corresponded to the catalytic core of the enzyme. The major epitope for 77% of CAR autoantibodies was found to be reactive with the peptide 218-222 (P = 0.0005) clustered within the α-helix. The analysis of epitope position in a 3D structure of the native CAII revealed their partial or full exposure on the protein surface. Anti-CAII autoantibodies from normal healthy controls did not share the major determinants with either group of patients. We also observed an epitope shift in antibody recognition from the AR-like epitope profile to the CAR-like profile in a patient who developed cancer 2 years after initial symptoms of vision loss (p < 0.0001). In conclusion, autoantibodies against CAII recognized different epitopes, depending whether they originated in patients with or without cancer. Also, antibodies targeted different determinates within the molecule during the development of retinopathy from non-paraneoplastic to paraneoplastic, suggesting an intramolecular epitope spreading phenomenon. Accurate distinction between AR and CAR is critical in designing immunotherapies and better diagnosis for those two conditions.

Anti-carbonic anhydrase II antibodies in end-stage renal disease patients.

OBJECTIVE: The aim of this study was to investigate the presence of anti-carbonic anhydrase (CA II) autoantibodies in patients with end-stage renal disease (ESRD) and relationships between the autoantibody titers and ghrelin, glucose, blood urea nitrogen (BUN) and creatinine. SUBJECTS AND METHODS: Serum CA II autoantibody titers, malondialdehyde (MDA), BUN, creatinine and ghrelin levels were measured in 45 ESRD patients and 45 healthy subjects. RESULTS: The CA II autoantibody titers in the ESRD group (0.170 ± 0.237) were significantly higher than those in the control group (0.079 ± 0.032; p = 0.035). MDA and ghrelin levels were also significantly higher in the ESRD group (p < 0.001). A weak positive correlation was determined between anti-CA II antibody titers and MDA, and a negative correlation was observed between ghrelin levels and anti-CA II antibody titers (r = 0.287, p = 0.028 and r = -0.278, p = 0.032, respectively). CONCLUSIONS: In ESRD patients, the results showed the development of an autoimmune response against CA II. This suggests that anti-CA II antibodies could be involved in the pathogenesis of ESRD.

Malondialdehyde and CA II autoantibody levels are elevated in children with undescended testes.

PURPOSE: In the pathogenesis of sub-fertility/infertility and testicular cancer related to undescended testes, oxidative stress, inflammation and autoimmunity are important factors. Therefore, the present study was designed to determine serum oxidative stress markers and carbonic anhydrase (CA) II autoantibodies in boys with undescended testes (UDT), and to investigate the relationship between these parameters. METHODS: Serum CA II autoantibody titers, malondialdehyde (MDA), ischemia modified albumin (IMA), protein carbonyl content and soluble CD40 ligand (sCD40L) levels were measured in 59 boys with UDT and 30 healthy subjects. RESULTS: MDA levels were significantly higher in the UDT group compared with the control group (p = 0.003). There was no significant difference between serum IMA, sCD40L or protein carbonyl levels. CA II autoantibody titers in the UDT group were significantly higher compared with those of the control group (p = 0.048). A weak positive correlation was determined between anti-CA II antibody titers and MDA and IMA levels (p = 0.041, p = 0.005, respectively). CONCLUSIONS: MDA is the most reliable and decisive biochemical marker displaying oxidative damage in undescended testes, and an autoimmune response may be triggered by oxidative stress against CA II during the UDT process.

Acute tubulointerstitial nephritis with an autoantibody response against carbonic anhydrase II.

An autoantibody against carbonic anhydrase II was identified in a case of acute tubulointerstitial nephritis induced by famotidine, which inhibits carbonic anhydrase II in addition to the gastric proton pump. The patient's serum reacted with distal nephron homogenates at the same molecular weight as purified carbonic anhydrase II, and immunohistochemistry using the patient's serum showed staining at the distal nephron. Carbonic anhydrase II may be a causative antigen in the famotidine-induced acute tubulointerstitial nephritis.

Paraneoplastic vitelliform retinopathy: clinicopathologic correlation and review of the literature.

Traditionally, the paraneoplastic retinopathies have been classified into two groups: melanoma-associated retinopathy (MAR) and cancer-associated retinopathy. MAR occurs in individuals with metastatic cutaneous or uveal melanoma and is characterized by nyctalopia, photopsias, and variable vision loss. In most cases, the fundus is essentially normal in appearance. More recently, there have been multiple reports of a MAR-like retinopathy with associated detachments of the retinal pigment epithelium and neurosensory retina. Such a clinical presentation has been termed paraneoplastic vitelliform retinopathy. We describe an 80-year-old man with metastatic cutaneous melanoma who developed paraneoplastic vitelliform retinopathy. For the first time, histopathology from enucleation specimens provides a clinicopathologic disease correlation with focal abnormalities in the inner nuclear and outer plexiform layers.

Carbonic anhydrase II autoantibody and oxidative stress in rheumatoid arthritis.

OBJECTIVES: To investigate the relationship between carbonic anhydrase (CA) II autoantibody and lipid peroxidation, certain antioxidant parameters, and cytokines in rheumatoid arthritis (RA) patients. DESIGN AND METHODS: Serum levels of CA II autoantibody, cytokines (TNFα, IL-6, IFN-γ, IL-1ß) and bone markers (crosslaps, osteocalcine) and erythrocyte levels of antioxidant enzyme activities (SOD, CAT, GPx), GSH and MDA, and CA activities were measured in RA patients and healthy controls. RESULTS: The CA II autoantibody titers were significantly higher (P<0.05), and erythrocyte SOD activities were significantly lower (P<0.05) in RA patients. A significant negative correlation between CA II autoantibody titers and SOD activities in RA group was established (r=-0.430, p=0.006). The elevated cytokine levels could not be correlated with CA II autoantibody levels in RA. CONCLUSION: These results suggest that increased erythrocyte oxidative stress observed in RA may be effective in the mechanism of CA II autoantibody formation.

Serum anti-carbonic anhydrase II antibodies and oxidant-antioxidant balance in pre-eclampsia.

PROBLEM The aim of this study was to investigate the presence of anti-carbonic anhydrase II antibodies (anti-CA II) antibodies in pre-eclampsia and the relationships between the autoantibodies, total antioxidant capacity (TAC) and total oxidant capacity (TOC), malondialdehyde (MDA) and oxidative stres index (OSI) parameters. METHOD OF STUDY We studied 40 early and late onset pre-eclamptic patients and 40 healthy pregnant control and 39 healthy non-pregnant control subjects. Serum CA II antibodies, TAC and TOC, and MDA parameters were studied by ELISA. RESULTS The mean values for TAC, TOC, OSI, MDA, and anti-CA II were significantly increased in patients with pre-eclampsia compared to the other groups. The anti-CA II antibody levels for the pregnant control subjects were 0.129 ± 0.04 and that for the pre-eclamptic patients were 0.282 ± 0.18. In this study, any absorbance value higher than 0.136, the mean absorbance + 2 S.D. of pregnant control subjects, was defined as positive. Positive results were obtained in 29 of 40 pre-eclamptic patients (72.5%). There were significant positive correlations between serum anti-CA II antibodies and TOC, MDA levels, and OSI levels. CONCLUSION The results suggest that anti-CA II antibodies and impairment in oxidant-antioxidant balance may be involved in multifactorial etiology of pre-eclampsia.

Analysis of humoral immune response in experimental autoimmune pancreatitis in mice.

OBJECTIVES: To study the autoimmune response in MRL/Mp mice, which spontaneously develop pancreatitis in the exocrine pancreatic tissue. METHODS: Six-week-old female mice were injected intraperitoneally with polyinosinic polycytidylic acid at a dose of 5 mg/kg of body weight twice a week for up to 12 weeks. The mice were serially killed, and the severity of their pancreatitis was graded with a histological scoring system. Immunohistological examinations were performed, and the serum levels of autoantibodies were measured by enzyme-linked immunosorbent assay. RESULTS: The administration of polyinosinic polycytidylic acid accelerated the development of pancreatitis, with abundant infiltration of B220 B cells and CD138 plasmacytes. Various autoantibodies directed against autoantigens, including carbonic anhydrase II and lactoferrin, were detected but none against glutamic acid decarboxylase. Of these, autoantibodies directed against the pancreatic secretory trypsin inhibitor (PSTI; 91.7%) were more prevalent than those against carbonic anhydrase II (33.3%) or lactoferrin (45.8%). Determination of the epitope of the anti-PSTI antibody showed that most immunoreactivity was directed at the site on PSTI that is active in the suppression of trypsin activity. CONCLUSIONS: The autoimmune response to PSTI protein may induce a failure of PSTI activity, resulting in the activation of trypsinogen and the subsequent disease progression.

Serum anti-carbonic anhydrase I and II antibodies and idiopathic recurrent pregnancy loss.

In up to 50% of recurrent pregnancy losses (RPL), the underlying pathophysiological mechanisms remain undetermined. Immunological factors may be involved. The objective of this study was to compare serum concentrations of autoantibodies to carbonic anhydrase (CA) I and II in women with and without RPL. Serum anti-CA-I and anti-CA-II concentrations in 29 women with RPL and 39 women without RPL on menstrual cycle day 3 were assessed and compared for this prospective age-matched controlled study. The mean serum anti-CA-I (0.287 +/- 0.177 versus 0.184 +/- 0.093, P = 0.003) and anti-CA-II (0.496 +/- 0.240 versus 0.344 +/- 0.108, P = 0.001) antibody concentrations were significantly higher in women with RPL, compared with controls. For serum anti-CA-I, an absorbance higher than 0.463 was taken as positive (mean + 3 SD of controls) and was detected in four of 29 patients with RPL (13.79%, 0.287 +/- 0.177). For serum anti-CA-II, an absorbance higher than 0.668 was taken as positive (mean + 3SD of controls) and was detected in seven of 29 patients with RPL (24.14%, 0.496 +/- 0.240). All patients with positive anti-CA-I antibody also had positive anti-CA-II antibody. Antibodies specifically reactive to CA-I and CA-II were found to be present at a higher frequency in the serum of subjects with RPL.

Autoimmunity against carbonic anhydrase II affects retinal cell functions in autoimmune retinopathy.

Autoantibodies against various retinal proteins, including anti-carbonic anhydrase II (CAII) autoantibodies, have been found in patients with cancer-associated retinopathy and autoimmune retinopathy without diagnosed cancer. We studied sera from retinopathy patients that showed reactivity with a 30-kDa retinal protein, which was identified as carbonic anhydrase II (CAII), and immunolabeled cells in human retina. The goal of the study was to examine whether patients' autoantibodies induce pathogenic effects on the catalytic function of CAII, which may have metabolic consequences on cell survival. Our findings revealed that anti-CAII autoantibodies have the capacity to induce cellular damage by impairing CAII cellular function through inhibiting the catalytic activity of CAII in a dose dependent manner, decreasing intracellular pH, increasing intracellular calcium, which in effect decreases retinal cell viability. The destabilized catalytic function of CAII and alterations in cytosolic pH were found very early, suggesting that autoantibodies are the inducers of apoptosis. In summary, our study showed that anti-CAII autoantibodies provoke pathogenic effects on retinal cells by decreasing cell survival by blocking the CAII cellular functions. The current experiments may facilitate better understanding the role of the immune system in retinal degeneration and help to develop better strategies for therapy of autoimmune retinopathy.

Autoantibody targets and their cancer relationship in the pathogenicity of paraneoplastic retinopathy.

Paraneoplastic retinopathies (PR), including cancer-associated retinopathy (CAR) or the closely related melanoma-associated retinopathy (MAR) occur in a small subset of patients with retinal degeneration and systemic cancer. This autoimmune syndrome is characterized by sudden, progressive loss of vision in association with circulating anti-retinal autoantibodies. The PR syndromes are heterogeneous, may produce a number of ocular symptoms, and may be associated with several different neoplasms, including lung, breast, prostate, gynecological, and colon cancer, melanoma, and hematologic malignancies. We examined the onset of retinopathy in correlation to the diagnosis of cancer and the presence of specific anti-retinal autoantibodies in PR patients. In some patients without diagnosed malignant tumors, the onset of ocular symptoms and the presence of autoantibodies preceded the diagnosis of cancer by months to years, including anti-recoverin, anti-transducin-alpha, and anti-carbonic anhydrase II antibodies. Although anti-retinal autoantibodies may not be a good predictor of a specific neoplasm, they can be used as biomarkers for different subtypes of retinopathy. Identification of autoantibodies involved in autoimmune-mediated PR will help elucidate the mechanisms underlying the PR syndromes and develop targeted therapies for these sight-threatening disorders.

Distinct autoantibodies against exocrine pancreatic antigens in European patients with type 1 diabetes mellitus and non-alcoholic chronic pancreatitis.

CONTEXT: Histopathological analysis has demonstrated lymphocytic infiltration in both the endocrine and the exocrine pancreas in some patients with type 1 diabetes and non-alcoholic chronic pancreatitis, suggesting an immune-mediated mechanism which affects both diabetes mellitus and chronic pancreatitis. OBJECTIVE: The examination of exocrine pancreatic humoral markers in Caucasian patients with respect to the interactions between exocrine and endocrine pancreatic diseases. PATIENTS: One hundred and thirty-six European Caucasian subjects subdivided into three groups: type 1 diabetes (n=48); non-alcoholic chronic pancreatitis (n=48); controls (n=40). MAIN OUTCOME MEASURE: Autoantibodies against carbonic anhydrase II (CAIIAb) and lactoferrin (LACAb) (both of which are exocrine pancreatic antigens) were analyzed by enzyme-linked immunosorbent assay. RESULTS: No positivity for CAIIAb and LACAb were found in the controls. Patients with type 1 diabetes had a significantly higher prevalence of CAIIAb (25.0%) than the controls while the prevalence of LACAb (8.3%) was not significantly higher than the controls. The prevalence of CAIIAb (12.5%) and LACAb (20.8%) in the patients with non-alcoholic chronic pancreatitis was significantly higher than that in the controls. A significantly higher prevalence of CAIIAb and/or LACAb was found in patients with type 1 diabetes (29.2%) and non-alcoholic chronic pancreatitis (22.9%) compared to that in the controls (0%). There was a significant association between CAIIAb and LACAb titers both in patients with type 1 diabetes (P=0.042) and in patients with non-alcoholic chronic pancreatitis (P<0.001). CONCLUSION: We have clearly demonstrated that some European Caucasian patients with type 1 diabetes and non-alcoholic chronic pancreatitis have autoantibodies against the exocrine pancreatic antigens CAIIAb and LACAb.

Potential for differential diagnosis of autoimmune pancreatitis and pancreatic cancer using carbonic anhydrase II antibody.

OBJECTIVES: Pancreatic ductal epithelia contain an abundance of carbonic anhydrase (CA), and the presence of antibodies to this enzyme has been described in autoimmune disorders. We previously found a small amount of an immunoglobulin G-like material in purchased CAII reagents, which led to pseudopositive reactions. METHODS: We determined the optimum measurement conditions for detecting anti-CAII antibody using an enzyme-linked immunosorbent assay and sera from 140 patients with pancreatic diseases. RESULTS: Compared with the prevalence of anti-CAII antibody in healthy subjects, a significantly higher seroprevalence of the antibody was detected in patients with autoimmune pancreatitis (AIP) (88.9%, P < 0.02), Sjögren syndrome (67.6%, P < 0.01), and alcoholic chronic pancreatitis (45.8%, P < 0.01). No positive results were obtained among patients with pancreatic cancer. Moreover, the antibody value obtained in the pancreatic cancer patients was actually lower than that obtained in healthy subjects. CONCLUSIONS: The anti-CAII antibody is probably not a specific marker of AIP because it was present at a higher frequency in the sera of patients with other pancreatic diseases. Nevertheless, the anti-CAII antibody may be a useful tool for the differential diagnosis of AIP and pancreatic cancer.

Induction of anti-carbonic-anhydrase-II antibody causes renal tubular acidosis in a mouse model of Sjogren's syndrome.

BACKGROUND/AIM: We recently reported that renal tubular acidosis (RTA) in Sjogren's syndrome (SjS) is associated with high titers of an autoantibody against carbonic anhydrase (CA) II, an important enzyme in renal acid-base regulation. The purpose of this study was to determine whether a CA-II antibody could cause RTA in a mouse model of SjS. METHODS: PL/J mice were immunized with human CA II to induce CA II antibody formation, whereas controls were injected with phosphate-buffered saline and adjuvant. After 6 weeks, anti-CA-II antibody titers were measured, then ammonium chloride was administered orally for 1 week to detect any acidification defect. RESULTS: CA-II-immunized mice showed higher anti-CA-II antibody titers than control mice. Pathologically, lymphocytic and plasma cell infiltration was seen in the salivary glands and kidneys of CA-II-immunized mice, but not in controls. On acid loading, blood pH and urine pH decreased in both groups of mice, but the slope of urine pH versus blood pH was less steep in the CA-II-immunized mice, suggesting that these mice had an impaired ability to reduce their urine pH in the face of metabolic acidosis. CONCLUSION: CA-II-immunized mice had a urinary acidification defect, which may be similar to that seen in patients with SjS.