Selecting a PRO-CTCAE-based subset for patient-reported symptom monitoring in prostate cancer patients: a modified Delphi procedure.

BACKGROUND: Clinician-based reporting of adverse events leads to underreporting and underestimation of the impact of adverse events on prostate cancer patients. Therefore, interest has grown in capturing adverse events directly from patients using the Patient-Reported Outcomes (PROs) version of the Common Terminology Criteria for Adverse Events (CTCAE). We aimed to develop a standardized PRO-CTCAE subset tailored to adverse event monitoring in prostate cancer patients. MATERIALS AND METHODS: We used a mixed-method approach based on the 'phase I guideline for developing questionnaire modules' by the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life group, including a literature review, and interviews with patients (n = 30) and health care providers (HCPs, n = 16). A modified Delphi procedure was carried out to reach consensus on the final subset selected from the complete PRO-CTCAE item library. RESULTS: Fourteen multidisciplinary HCPs and 12 patients participated in the Delphi rounds. Ninety percent agreed on the final subset, consisting of: 'ability to achieve and maintain erection', 'decreased libido', 'inability to reach orgasm', 'urinary frequency', 'urinary urgency', 'urinary incontinence', 'painful urination', 'fecal incontinence', 'fatigue', 'hot flashes', 'feeling discouraged', 'sadness', and 'concentration'. From 16 articles identified in the literature review, the following adverse events for which no PRO-CTCAE items are available, were included to the recommendation section: 'nocturia', 'blood and/or mucus in stool', 'hemorrhoids', 'hematuria', 'cystitis', 'neuropathy', and 'proctitis'. CONCLUSIONS: The obtained PRO-CTCAE-subset can be used for multidisciplinary adverse event monitoring in prostate cancer care. The described method may guide development of future PRO-CTCAE subsets.

Androgen Deprivation therapy for Oligo-recurrent Prostate cancer in addition to radioTherapy (ADOPT): study protocol for a randomised phase III trial.

BACKGROUND: More than 60% of oligo-recurrent prostate cancer (PCa) patients treated with metastasis-directed radiotherapy (MDRT) develop biochemical recurrence within 2 years. This recurrence rate emphasises the need for improved treatment and patient selection. In line with the treatment of primary PCa, the efficacy of MDRT may be enhanced when combined with androgen-deprivation therapy (ADT). Furthermore, the availability of PSMA PET/CT offers an excellent tool for optimal patient selection for MDRT. This phase III randomised controlled trial will investigate the role of the addition of ADT to MDRT in oligo-recurrent PCa patients selected with PSMA PET/CT to enhance oncological outcome. METHODS: Two hundred and eighty patients will be randomised in a 1:1 ratio to the standard treatment arm (MDRT alone) or the experimental arm (MDRT + 6 months ADT). Patients with biochemical recurrence after primary treatment of PCa presenting with ≤ 4 metastases will be included. The primary endpoint is the 2.5-year metastases progression-free survival (MPFS). Secondary endpoints are acute and late toxicity, quality of life, biochemical progression-free survival, overall survival, and the sensitivity of the PSMA PET/CT for detecting oligometastases at low PSA-levels. So far, between March 2020 and December 2021, one hundred patients have been included. DISCUSSION: This phase III randomised controlled trial will assess the possible benefit of the addition of 6 months ADT to MDRT on metastases progression-free survival, toxicity, QoL and survival in PCa patients with 1-4 recurrent oligometastatic lesions. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04302454 . Registered 10 March 2020.

Phase III randomised controlled trial on PSMA PET/CT guided hypofractionated salvage prostate bed radiotherapy of biochemical failure after radical prostatectomy for prostate cancer (PERYTON-trial): study protocol.

BACKGROUND: Salvage external beam radiotherapy (sEBRT) for patients with a biochemical recurrence (BCR) after radical prostatectomy provides a 5-year biochemical progression-free survival up to 60%. Multiple studies have shown that dose escalation to the primary prostate tumour improves treatment outcome. However, data is lacking on the role of dose escalation in the recurrent salvage setting. The main objective of the PERYTON-trial is to investigate whether treatment outcome of sEBRT for patients with a BCR after prostatectomy can be improved by increasing the biological effective radiation dose using hypofractionation. Moreover, patients will be staged using the PSMA PET/CT scan, which is superior to conventional imaging modalities in detecting oligometastases. METHODS: The PERYTON-study is a prospective multicentre open phase III randomised controlled trial. We aim to include 538 participants (269 participants per treatment arm) with a BCR after prostatectomy, a PSA-value of < 1.0 ng/mL and a recent negative PSMA PET/CT scan. Participants will be randomised in a 1:1 ratio between the conventional fractionated treatment arm (35 × 2 Gy) and the experimental hypofractionated treatment arm (20 × 3 Gy). The primary endpoint is the 5-year progression-free survival after treatment. The secondary endpoints include toxicity, quality of life and disease specific survival. DISCUSSION: Firstly, the high rate of BCR after sEBRT may be due to the presence of oligometastases, for which local sEBRT is inappropriate. With the use of the PSMA PET/CT before sEBRT, patients with oligometastases will be excluded from intensive local treatment to avoid unnecessary toxicity. Secondly, the currently applied radiation dose for sEBRT may be too low to achieve adequate local control, which may offer opportunity to enhance treatment outcome of sEBRT by increasing the biologically effective radiotherapy dose to the prostate bed. TRIAL REGISTRATION: This study is registered at ClinicalTrials.gov (Identifier: NCT04642027 ). Registered on 24 November 2020 - Retrospectively registered. The study protocol was approved by the accredited Medical Ethical Committee (METc) of all participating hospitals (date METc review: 23-06-2020, METc registration number: 202000239). Written informed consent will be obtained from all participants.

Increased rectal wall stiffness after prostate radiotherapy: relation with fecal urgency.

BACKGROUND: Late anorectal toxicity is a frequent adverse event of external beam radiotherapy (EBRT) for prostate cancer. The pathophysiology of anorectal toxicity remains unknown, but we speculate that rectal distensibility is impaired due to fibrosis. Our goal was to determine whether EBRT induces changes of rectal distensibility as measured by an electronic barostat and to explore whether anorectal complaints are related to specific changes of anorectal function. METHODS: Thirty-two men, irradiated for localized prostate carcinoma, underwent barostat measurements, anorectal manometry, and completed a questionnaire prior to and 1 year after radiotherapy. The primary outcome measure was rectal distensibility in response to stepwise isobaric distensions. In addition, we assessed sensory thresholds, anal pressures, and anorectal complaints. KEY RESULTS: External beam radiotherapy reduced maximal rectal capacity (227 ± 14 mL vs 277 ± 15 mL; P < 0.001), area under the pressure-volume curve (3212 ± 352 mL mmHg vs 3969 ± 413 mL mmHg; P < 0.005), and rectal compliance (15.7 ± 1.2 mL mmHg(-1) vs 17.6 ± 0.9 mL mmHg(-1) ; P = 0.12). Sensory pressure thresholds did not significantly change. Sixteen of the 32 patients (50%) had one or more anorectal complaints. Patients with urgency (n = 10) had a more reduced anal squeeze and maximum pressure (decrease 29 ± 11 mmHg vs 1 ± 7 mmHg; P < 0.05 and 31 ± 12 mmHg vs 2 ± 8 mmHg; P < 0.05 respectively) compared with patients without complaints, indicating a deteriorated external anal sphincter function. CONCLUSIONS & INFERENCES: Irradiation for prostate cancer leads to reduced rectal distensibility. In patients with urgency symptoms, anal sphincter function was also impaired.

Expression of Ro/SS-A and La/SS-B determined by immunohistochemistry in healthy, inflamed and autoimmune diseased human tissues: a generalized phenomenon.

OBJECTIVE: Autoantibodies to the ribonucleoproteins Ro/SS-A and La/SS-B are found in autoimmune diseases such as primary Sjögren's syndrome (pSS), systemic lupus erythematousus and rheumatoid arthritis. Increased and aberrant expression of Ro/SS-A and La/SS-B in target organs, which have been reported in the recent literature, might contribute to their antigenicity. However, data on the expression of Ro/SS-A and La/SS-B in other inflammatory conditions are scarce. MATERIALS AND METHODS: Using monoclonal antibodies against Ro/SS-A and La/SS-B, we studied the expression of these antigens in paraffin-embedded healthy tissue, aspecific inflamed tissue, the neonatal and adult cardiac conduction systems and labial salivary gland tissues of patients suspected of having pSS. RESULTS: In healthy tissues, the nuclei expressed both Ro/SS-A and La/SS-B. This expression was stronger in inflamed tissues. Nucleoli were negative and cytoplasmic expression was weaker than nuclear expression. No increased or aberrant expression of Ro/SS-A or La/SS-B was observed in either neonatal or adult atrioventricular nodes and bundle branches. More pSS patients showed high La/SS-B immunoreactivity levels in their labial salivary gland ductal cell nuclei than non-Sjögren's syndrome sicca patients. CONCLUSIONS: Ro/SS-A and La/SS-B expression is a generalized cell biological phenomenon and may be upregulated by increased cell activation both in aspecific and autoimmune-mediated inflammation. In pSS the high expression of La/SS-B in labial salivary, gland ductal cell nuclei might contribute to the local immune response.

Time between onset of apoptosis and release of nucleosomes from apoptotic cells: putative implications for systemic lupus erythematosus.

OBJECTIVE: To investigate the kinetics of nucleosome leakage from apoptotic cells in an in vitro system and extrapolate the results to autoimmune disease, in particular systemic lupus erythematosus. METHODS: A sensitive nucleosome enzyme linked immunosorbent assay (ELISA) was developed, using a monoclonal antibody (mAb) against histone 3 and an mAb against nucleosomes. Nucleosome release during apoptotic cell death was studied in Jurkat cells. AnnexinV binding (early apoptosis) and propidium iodide positivity (late apoptosis) of the cells were compared with nucleosome release at different times after apoptosis induction. RESULTS: Nucleosomes appeared in culture supernatant of Jurkat cells 24 to 48 hours after apoptosis induction, when the cells had been late apoptotic for more than 12 hours. CONCLUSION: Nucleosomes are released from late apoptotic Jurkat cells, with a 12 hour delay from the appearance of AnnexinV binding cells. This result suggests that in vivo scavenger mechanisms have 12 hours to remove apoptotic material from the circulation.

Methodological update detection of antibodies to dsDNA: current insights into its relevance.

Ever since its first discovery in 1957, anti-DNA has taken a special place amongst the other antinuclear antibodies. Even today, it stands out between these, because of its high specificity for one particular disease: systemic lupus erythematosus (SLE). Furthermore, anti-DNA has been shown to actually play a role in a key disease feature of SLE: lupus nephritis. Binding of anti-DNA to the glomerular basement membrane of the kidney has been shown to be mediated by nucleosomes. More recently, it has been shown that patients with SLE also have antibodies specific for nucleosomes in their circulation. It may well be that anti-nucleosome detection in the near future will prove to be of more relevance than anti-DNA detection. Nucleosomes also seem to play a key role in the induction of anti-DNA (and anti-nucleosome) production. Mechanisms involved in this process may include defects in apoptosis and/or clearance of apoptotic material. Studies of these mechanisms will help us to decipher the cause of autoantibody production, or indeed of autoimmune diseases such as SLE.

Systemic lupus erythematosus. Disease outcome in patients with a disease duration of at least 10 years: second evaluation.

Data related to the disease course of patients with systemic lupus erythematosus (SLE) with special attention to the persistence of disease activity in the long term are scarce. At this moment reliable figures are only known about the survival rate as a measure of outcome. The aim of this multicenter study was to describe the outcome of SLE patients with a disease duration of greater than 10 y. Outcome parameters were two disease activity-scoring systems (SLEDAI and ECLAM), the end organ damage (SLICC/ACR damage index) and treatment. Our results are derived from 187 SLE patients followed at 10 different centres in Europe over a period of 1 y. Serious clinical signs or exacerbations, defined by the occurrence or detoriation of already existing symptoms of renal and cerebral nervous systems were observed in 2-11% of the patients, seizures and psychosis in 3%, proteinuria in 11% and an increase in serum creatinine in 5% of the patients. No change took place in the overall damage index. Yet, the disease course in most patients was characterized by periods of tiredness (42-60%), arthritis (20-25%), skin involvement such as malar rash (32-40%), migraine (15-20%), anaemia (15%) and leucopenia (17-19%). Summarizing these results it is shown that patients, still under care after such a long time of having this disease, do have a disease that is far from extinguished.

Incomplete lupus erythematosus: results of a multicentre study under the supervision of the EULAR Standing Committee on International Clinical Studies Including Therapeutic Trials (ESCISIT).

OBJECTIVE: Patients characterized with antinuclear antibodies (ANA) and disease symptoms related to one organ system can be described as having incomplete systemic lupus erythematosus (SLE). The aim of this multicentre study was to describe the outcome of these so-called incomplete SLE patients. Two aspects of the outcome were studied: (i) the disease course, defined by the presence or absence of clinical symptoms; and (ii) the number of patients that eventually developed full SLE. METHODS: Outcome parameters were the ACR criteria, the SLE disease Activity Index (SLEDAI), the European Consensus Lupus Activity Measure (ECLAM) and the requirement for treatment. In 10 European rheumatology centres, patients who had been evaluated in the last 3 months of 1994 and had been diagnosed as having incomplete SLE on clinical grounds for at least 1 yr were included in the study. All 122 patients who were included in the study were evaluated annually during 3 yr of follow-up. RESULTS: Our results are confined to a patient cohort defined by disease duration of at least 1 yr, being under clinical care at the different centres in Europe. These patients showed disease activity that was related mostly to symptoms of the skin and the musculoskeletal system, and leucocytopenia. During the follow-up, low doses of prednisolone were still being prescribed in 43% of the patients. On recruitment to the study, 22 of the 122 incomplete SLE patients already fulfilled the ACR criteria for the diagnosis of SLE. In the 3 yr of follow-up only three patients developed SLE. CONCLUSIONS: A high proportion of patients in our cohort defined on clinical grounds as having incomplete SLE eventually showed disease activity defined by the SLEDAI as well as ECLAM. However, only three cases developed to SLE during the follow-up. This suggests that incomplete SLE forms a subgroup of SLE that has a good prognosis.

Assessment of antibodies to double-stranded DNA induced in rheumatoid arthritis patients following treatment with infliximab, a monoclonal antibody to tumor necrosis factor alpha: findings in open-label and randomized placebo-controlled trials.

OBJECTIVE: To compare the incidence of anti-double-stranded DNA (anti-dsDNA) antibodies in rheumatoid arthritis (RA) patients receiving either single or multiple doses of a chimeric anti-tumor necrosis factor alpha (anti-TNFalpha) antibody or placebo infusions, with or without methotrexate, in open-label, randomized, placebo-controlled trials. METHODS: Multiple sera obtained from 156 patients before and after treatment with infliximab and from 37 patients treated with placebo infusions were tested for anti-dsDNA antibodies by 3 methods: Crithidia luciliae indirect immunofluorescence test (CLIFT), a commercial Farr assay (Ortho Diagnostics radioimmunoassay [RIA]) in which the antigen source is mammalian DNA, and a Farr assay employing 125I-labeled circular plasmid DNA (Central Laboratory of The Netherlands Red Cross Blood Transfusion Service [CLB] RIA). Patients with positive findings on the CLIFT were also tested for antibodies to histones (H1-H5) and chromatin and for IgM rheumatoid factors (IgM-RFs). RESULTS: None of the RA patients had a serum sample that was positive for anti-dsDNA antibodies by the CLIFT prior to infliximab therapy. Of the 22 patients who developed a positive CLIFT result, 11 (7% of 156 exposed to infliximab) also had positive findings on the Ortho RIA at a concentration of >10 units/ml and another 8 (5%) were positive at a concentration of >25 units/ml. In all but 1 patient, the anti-dsDNA antibodies were solely of the IgM isotype. Only 1 patient had detectable anti-dsDNA antibodies by the CLB RIA. All sera containing anti-dsDNA by the CLIFT contained antibodies to chromatin, and sera from 2 patients also contained antibodies to histones. IgM-RF titers showed a significant reduction following infliximab therapy in these 22 patients. One patient developed anti-dsDNA antibodies of IgG, IgA, and IgM isotype and had positive results on both Farr assays (peaking at 22 weeks and resolving by 54 weeks); this was associated with a reversible lupus syndrome. CONCLUSION: Anti-dsDNA antibodies of IgM class are induced by infliximab therapy; the frequency is dependent on the assay method used. Only 1 of the 156 patients who were treated with infliximab developed a self-limiting clinical lupus syndrome; that patient developed high titers of anti-dsDNA antibodies of IgG, IgM, and IgA class, as detected by the CLIFT and by 2 different Farr assays.

Histone-containing immune complexes are to a large extent responsible for anti-dsDNA reactivity in the Farr assay of active SLE patients.

Increased titres of anti-dsDNA antibodies, especially if of high avidity, are associated with renal exacerbations in patients with systemic lupus erythematosus (SLE). One of the most reliable assays to measure anti-dsDNA antibodies, the Farr assay, is believed to detect preferentially high avidity antibodies. Purified non-complexed monoclonal antibodies (mAbs) against nucleosomes, obtained from mice with SLE, are not reactive in the Farr assay, but can become so once complexed to nucleosomes. These Farr-positive, nucleosome containing, immune complexes were also able to bind in vivo to the glomerular basement membrane (GBM), predominantly via heparan sulphate (HS). To evaluate whether in SLE patients the same kind of immune complexes are responsible for Farr reactivity, IgG from serum or plasma was isolated under dissociating and physiological conditions. We observed that after purification under dissociating conditions, Farr reactivity was significantly decreased (P<0.0001) in contrast to reactivity with histones and two 'control' antigens: Epstein Barr Virus (EBV) and Ro/SS-A. Reactivity with nucleosomes also decreased after purification, although to a lesser extent. Plasma purified under physiological conditions showed no decrease in Farr reactivity. The importance of histones for the generation of immune complexes is supported by the two following observations. Firstly, the presence of histones could be demonstrated in serum and plasma of SLE patients but not in serum of healthy controls or in IgG preparations purified under dissociating conditions. Secondly, Farr reactivity of purified IgG preparations could be restored by addition of purified histones. From these studies we conclude that histones containing immune complexes are responsible for a large part of the Farr reactivity in active SLE, and are therefore indirectly implicated in the pathogenesis of lupus nephritis.

Systemic lupus erythematosus: clinical features in patients with a disease duration of over 10 years, first evaluation.

OBJECTIVE: Most information available about the disease course of patients with systemic lupus erythematosus (SLE) is restricted to the first 5 yr after disease onset. Data about the disease course 10 yr after disease onset are rare. The aim of this multicentre study was to describe the outcome of SLE patients with a disease duration of >10 yr. METHODS: Outcome parameters were the SLE Disease Activity Index (SLEDAI), the European Consensus Lupus Activity Measure (ECLAM), the Systemic Lupus International Collaborative Clinics/American College of Rheumatology Damage Index (SLICC/ACR), a global damage index (DI) and required treatment. In 10 different European rheumatology centres, all SLE patients who were evaluated in the last 3 months of 1994, and who had been diagnosed with SLE at least 10 yr ago, were included in the study. RESULTS: It should be stressed that our results are confined to a patient cohort, defined by a disease duration of at least 10 yr, and who are still under clinical care at the different centres in Europe. These SLE patients still showed some disease activity, related to symptoms of the skin and musculoskeletal systems, next to the presence of renal involvement. A total of 72% of the patients needed treatment with prednisolone (

[Immunology in medical practice. XXI. Laboratory tests for immunologic diseases]. / Immunologie in de medische praktijk. XXI. Laboratoriumdiagnostiek van immunologische ziekten.

Clinical immunology has gained its firm place in health care. There are now established laboratory tests giving insight into the functioning of the immune system in the normal and diseased individual. The laboratory diagnostic tests are related to immune deficiencies, infectious diseases, allergic diseases, autoimmune diseases (both generalized and organ-specific ones), the HLA system and malignancies of immune cells. In this review the application of a number of laboratory tests in the diagnosis of immunological diseases is discussed. In the Netherlands a laboratory specialist, the 'medical immunologist' deals with the development, implementation and performance of the immunological diagnostic tests in health care.

Patients with systemic lupus erythematosus with high plasma levels of sFas risk relapse.

OBJECTIVE: We related soluble Fas (sFas) levels to the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) in a longitudinal series of plasma samples of patients with SLE to evaluate the relation between excessive production of sFas and disease activity. METHODS: We generated 21 monoclonal antibodies against Fas. Two of these were used to develop and validate a sensitive sandwich ELISA for the longitudinal analysis of sFas levels in plasma of 30 patients and 25 controls. RESULTS: At the start of followup, a significant elevation (p<0.0001) was found in sFas levels in SLE (1167+/-347 pg/ml sFas) compared to controls (618+/-98 pg/ml sFas). Also, at the start of the followup a significant difference (p = 0.0028) existed between patients who were going to have a relapse (1236+/-402 pg/ml sFas) during followup and patients who were not (809+/-276 pg/ml sFas). While sFas did not fluctuate with disease activity in individual patients, we found a strong correlation (r = 0.75, p<0.0001) between sFas and SLEDAI, but only at the time of relapse, when we analyzed the patients as a group. CONCLUSION: In individual patients with SLE, sFas does not fluctuate with disease activity. However, patients with high plasma levels of sFas are at risk of relapse.

Do elevated levels of serum-soluble fas contribute to the persistence of activated lymphocytes in systemic lupus erythematosus?

Systemic lupus erythematosus (SLE) is characterized by generalized immune activation. Part of this might be explained by a decreased rate of apoptosis, possibly related to elevated levels of soluble Fas (sFas) which can inhibit Fas mediated apoptosis of lymphocytes. In order to substantiate the relation between levels of sFas and lymphocyte activation in SLE we monitored sFas levels, lymphocyte activation and disease activity in 25 SLE patients. SLEDAI scores were registered and sera were assayed for sFas levels by an enzyme-linked immunosorbent assay. Flow cytometry was used to monitor the state of activation of lymphocyte subsets. Eighteen healthy, age-matched volunteers served as controls. Soluble Fas levels were elevated in SLE patients (n=25) compared to healthy controls (n=18, P=0.002). Soluble Fas levels correlated with SLEDAI scores (r=0.45, P=0.02). Levels of sFas correlated with the percentages of activated B cells defined as CD20(+)CD38(+) cells (r=0.47, P=0.009). Percentages of CD20(+)CD38(+) cells were increased in quiescent SLE compared to healthy controls (P=0.003). The expression of activation markers on CD4(+) T lymphocytes (IL-2R, P=0.04; HLA-DR, P=0.01) and CD8(+) T lymphocytes (HLA-DR, P=0.007) was also increased in quiescent SLE compared to controls. Activation markers on all lymphocyte subsets tended to increase further during disease activity. No correlation was observed between percentages of activated T lymphocyte subsets and levels of sFas. In conclusion, soluble Fas levels are increased in SLE patients and correlate with disease activity as measured by the SLEDAI score and B and T cell subsets are activated even during quiescent SLE. Serum levels of sFas correlate with percentages of activated B cells but not with that of activated T cells.

Range of antinuclear antibodies in "healthy" individuals.

OBJECTIVE: To determine the range of antinuclear antibodies (ANA) in "healthy" individuals compared with that in patients with systemic lupus erythematosus (SLE), systemic sclerosis (SSc; scleroderma), Sjögren's syndrome (SS), rheumatoid arthritis (RA), or soft tissue rheumatism (STR). METHODS: Fifteen international laboratories experienced in performing tests for ANA by indirect immunofluorescence participated in analyzing coded sera from healthy individuals and from patients in the 5 different disease groups described above. Except for the stipulation that HEp-2 cells should be used as substrate, each laboratory used its own in-house methodology so that the data might be expected to reflect the output of a cross-section of worldwide ANA reference laboratories. The sera were analyzed at 4 dilutions: 1:40, 1:80, 1:160, and 1:320. RESULTS: In healthy individuals, the frequency of ANA did not differ significantly across the 4 age subgroups spanning 20-60 years of age. This putatively normal population was ANA positive in 31.7% of individuals at 1:40 serum dilution, 13.3% at 1:80, 5.0% at 1:160, and 3.3% at 1:320. In comparison with the findings among the disease groups, a low cutoff point at 1:40 serum dilution (high sensitivity, low specificity) could have diagnostic value, since it would classify virtually all patients with SLE, SSc, or SS as ANA positive. Conversely, a high positive cutoff at 1:160 serum dilution (high specificity, low sensitivity) would be useful to confirm the presence of disease in only a portion of cases, but would be likely to exclude 95% of normal individuals. CONCLUSION: It is recommended that laboratories performing immunofluorescent ANA tests should report results at both the 1:40 and 1:160 dilutions, and should supply information on the percentage of normal individuals who are positive at these dilutions. A low-titer ANA is not necessarily insignificant and might depend on at least 4 specific factors. ANA assays can be a useful discriminant in recognizing certain disease conditions, but can create misunderstanding when the limitations are not fully appreciated.

Immunological aspects of congenital atrioventricular block.

Isolated congenital heart block (CHB) in children is strongly associated with the occurrence of autoantibodies to Ro/SS-A and La/SS-B in the circulation of the mother. Although these antibodies are generally found in patients with generalized autoimmune diseases, they may also occur in symptomless mothers of CHB patients. It is thought that anti-Ro/SS-A and anti-La/SS-B may reach the fetal circulation via transplacental transport, starting around the 20th week of gestation. Although several hypotheses have been put forward, the exact mechanism through which these autoantibodies bind the fetal conduction system and elicit a local inflammatory response is still unclear. Also, the induction of the autoantibody response in the mother remains largely obscure, although a putative role of viral infection has been suggested. In this overview, the structure of the involved antigens will be discussed, followed by the nature of the antibodies. Recent data regarding the etiology of the anti-Ro/SS-A and anti-La/SS-B response and the role of these autoantibodies in the pathogenesis of CHB will be presented.

Antigen specificity of anti-nuclear antibodies complexed to nucleosomes determines glomerular basement membrane binding in vivo.

Monoclonal anti-nuclear antibodies which are complexed to nucleosomes are able to bind to the glomerular basement membrane (GBM) in vivo, whereas purified antibodies do not bind. The positively charged histone moieties in the nucleosome are-responsible for the binding to anionic determinants in the GBM. We tested the hypothesis that the specificity of the autoantibodies complexed to the nucleosome influences the glomerular binding of the antibody-nucleosome complex. We induced the formation of these immune complexes in vivo, by intraperitoneal inoculation of hybridomas producing monoclonal anti-nuclear antibodies (four anti-histone, three anti-double stranded (ds)DNA and three anti-nucleosome antibodies) into nude BALB/c mice. In ascites and plasma from the mice inoculated with these hybridomas, nucleosome/autoantibody complexes were detected in comparable amounts. Immunofluorescence of kidney sections revealed that about 60% of the mice inoculated with anti-nucleosome or anti-dsDNA hybridomas had immunoglobulin deposits in the GBM, whereas only 15% of the mice with anti-histone hybridomas showed these deposits (p < or = 0.04). In the Matrigel-ELISA (used as a GBM surrogate) ascites from anti-nucleosome or anti-DNA hybridomas displayed significantly higher titers (p < or = 0.002) than ascites from anti-histone hybridomas. In conclusion, nucleosome/immunoglobulin complexes comprising anti-nucleosome or anti-dsDNA auto-antibodies do bind more frequently to the GBM in vivo than nucleosome/immunoglobulin complexes containing anti-histone antibodies. It therefore appears that the specificity of the antibody bound to the nucleosome is a critical determinant for the nephritogenic potential of the nucleosome-autoantibody complex.