Anti-nuclear antibody screening using HEp-2 cells

A Retrospective Study on Antinuclear Antibody Patterns in Systemic Lupus Erythematosus Patients and Its Correlation With Serological Markers

INTRODUCTION

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease. Detection of antinuclear antibodies (ANAs) aids in the diagnosis of SLE. The indirect immunofluorescence (IIF) assay is often used a routine screening test for the detection of ANA. The pathogenic role and significance of various patterns produced in IIF is yet to be explored.

AIM

This study aimed to detect ANA patterns generated by IIF and correlate these patterns with specific antibodies detected by line immunoassay. We also investigated the significance of each ANA pattern and its association with specific serological SLE markers, such as complement molecules, anti-dsDNA, antiphospholipid antibody, and C-reactive protein (CRP), along with associations with direct Coombs test (DCT).

MATERIALS AND METHODS

We conducted a retrospective study that included 204 patients newly diagnosed with SLE according to the European Alliance of Associations for Rheumatology/American College of Rheumatology (EULAR/ACR) criteria. The detection and pattern determination of ANA was performed by IIF using HEp-20-10. Furthermore, line immunoassay was performed, and the antibody profile of each sample was obtained. Other immunodiagnostic markers were analyzed, including C3, C4, anti-dsDNA, antiphospholipid antibodies (anti-cardiolipin antibodies, anti-beta-2-glycoprotein I, and lupus anticoagulant), CRP, and DCT.

RESULTS

Of the 204 samples, the most frequent ANA pattern observed was nucleus speckled (52.9%), followed by nucleus homogenous (27.5%), mixed (13.7%), and cytoplasm speckled (5.9%). The nucleus homogenous pattern showed the most pathogenic immune profile due to its close association with markers of disease activity, namely, high anti-dsDNA titer, low C3 level, and DCT positivity.  Conclusion: This study showed that the most common pattern associated with SLE is nucleus speckled, followed by the nucleus homogenous pattern. Based on associations with specific serological markers, the nucleus homogenous pattern may be linked to a high disease activity in SLE.

Investigation of Cytotoxic and Apoptotic Effects of Styrax Liquidus Obtained From Liquidambar orientalis Miller (Hamamelidaceae) on HEp-2 Cancer Cell with Caspase Pathway

OBJECTIVE

The HEp-2 cell line was first identified as laryngeal cancer cells. Then, it was reported to consist of cervical adenocarcinoma cells derived via HeLa cell line contamination. Styrax liquidus is an exudate that is provided by the injured hull of the Liquidambar orientalis Miller (Hamamelidaceae), which has been used for the treatment of skin problems, peptic ulcers, and parasitic infections or as an antiseptic. In our study, we purposed to research the cytotoxic and apoptotic effect of styrax liquidus on HEp-2 cancer cell line.

MATERIALS AND METHODS

The IC50 dosage of styrax liquidus (Turkish sweet gum obtained from trees) was set by the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, and the apoptotic effect of styrax liquidus on HEp-2 cancer cell was determined by assessing the expression of genes involved in apoptosis (Bax, Bad, Bak1, p53, Bcl-2, Bcl-XL, Apaf-1, Caspase2, Caspase3a, Caspase9, and Caspase12) by quantitative real-time polymerase chain reaction.

RESULTS

The IC50 value of styrax liquidus was found to be 125 μg/mL for 48 hours. According to the results, styrax liquidus reduced the population of HEp-2 laryngeal cancer cells and increased the expression of genes which were apoptosis related. These results indicate that styrax liquidus can be thought as a choice of cancer therapy.

CONCLUSION

The finding of the study showed that it would be more useful to perform more qualified studies about the effect of styrax liquidus on cancer cells.

The Role of Indirect Immunofluorescence (IIF) and Line Immunoassay (LIA) in the Diagnosis of Autoimmune Diseases and Their Clinical Correlation: An Observational Study From a Tertiary Care Center in Bihar

Background and aim The presence of distinct sets of autoantigens and autoantibodies bestow these autoimmune diseases (ADs) with specific immune profiles or fingerprints, which has cleared the diagnostic dilemma associated with these ADs. This study was planned to collate and compare the reporting of indirect immunofluorescence (IIF) with line immunoassay (LIA) and their clinical correlations. This study was conducted to investigate the association between the reporting of anti-nuclear antibody (ANA) screening by IIF and ANA profile reporting by LIA. Additionally, it aimed to explore the association of ANA pattern detection by IIF with the detection of autoantibodies against nuclear antigens by LIA and the association of autoantibody detection by LIA with clinical diagnosis. Methodology A total of 98 samples from patients suspected of having ADs were subjected to both IIF and LIA, and results were correlated with clinical diagnosis. Results In the homogenous pattern noted by IIF, the clustered antigens identified by LIA included dsDNA, Nucleosome, Histone, and Mi-2. In the speckled pattern, the identified antigens were SS-A/Ro52, P0, SS-A/Ro60, SS-B/La, and U1-snRNP. On the other hand, the nucleolar pattern revealed antigens AMA M2, PCNA, and CENP-B. The centromere pattern was mostly associated with CENP-B. The speckled pattern was found to be most commonly associated with systemic lupus erythematosus (SLE). The most common autoantibody found in total ANA profile-positive samples was anti-U1-snRNP followed by anti-SS-A/Ro60 and anti-SS-B/La, and all three were found to be associated with SLE. Conclusions SLE was the most common AD identified in our study samples, with the speckled pattern being the most common pattern on IIF and anti-U1-snRNP being the most common ANA identified by LIA. The fluorescence pattern of IIF predicts the presence of specific antibodies. LIA should be reserved for IIF-positive but dubious cases and whose signs and symptoms are nebulous and do not match the disease dictated by IIF.

The Frequency of Immunofluorescence Antinuclear Antibody Patterns and Extractable Nuclear Antigen: Experience From a Large Laboratory in Pakistan

Background Autoimmune disorders have shown an increasing incidence in the last few years. The systemic response to the disorder is characterized by the expression of antinuclear antibody (ANA), which serves as the serological hallmark of autoimmunity. Its presence may indicate either a systemic autoimmune disease such as systemic lupus erythematosus (SLE), scleroderma, and polymyositis/dermatomyositis or an organ-specific condition such as autoimmune thyroiditis and hepatitis. The systemic response may vary from one individual to another in each population. Several specific autoantibodies are also found to be associated with specific rheumatic diseases. Aim We aim to report the frequency of ANA positivity, ANA immunofluorescence patterns, and the presence of extractable nuclear antigen (ENA) among the general Pakistani population from one of the largest laboratories in Pakistan. Material and methods A total of 1,966 blood samples from a random Pakistani population were included, who were referred by their physicians with suspicion of autoimmune disease. These blood samples were subjected to ANA testing by indirect immunofluorescence method, and subsequently, positive samples were further analyzed for ENA detection in the Section of Chemical Pathology, Department of Pathology at Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan. An ANA titer of ≥1:80 was taken as positive. ANA was divided into subgroups based on titer: negative, weakly positive (titer of 1:80 or 1:160), moderately positive (titer of 1:320 or 1:640), and strongly positive (titer of ≥1:1280). Further, the frequency of ANA in male and female participants was studied in different age groups (2 to <10, 10 to <20, 20 to <30, 30 to <40, 40 to <50, 50 to <60, 60 to <70, 70 to <80, and 80+ years). Results This study included 1,966 participants, out of which 1,100 (55%) were ANA-positive at a titer of ≥1:80. Out of these ANA positives, the proportion of weakly positive (titer of 1:80 or 1:160), moderately positive (titer of 1:320 or 1:640), and strongly positive (titer of ≥1:1280) were 48.7%, 2.6%, and 4.2%, respectively. The ages ranged from two to 91 years, with a mean age of 43.64 ± 17.4 years. Females (75.5%) showed predominance over males (24.5%) in all age groups, with a ratio of 3:1. The age group in which most ANA positivity was found was 30 to <40 years. Among 1,100 ANA-positive sera, 383 (34.8%) participants tested positive for at least one out of 15 ENA. The most frequent autoantibodies noticed were anti-recombinant Ro52 (Ro52) (19.8%), anti-Sjogren's syndrome type A (SSA) (17.2%), and anti-ribonucleoprotein (RNP) (13.3%). The most prevalent ANA patterns were nuclear homogeneous (27.7%), followed by nuclear speckled (26.5%). Conclusion The frequency of ANA positivity is high in the Pakistani population and differs in different sex and age groups.

Autoimmune Hepatitis: Serum Autoantibodies in Clinical Practice

Circulating autoantibodies are a key diagnostic tool in autoimmune hepatitis (AIH), being positive in 95% of the cases if tested according to dedicated guidelines issued by the International Autoimmune Hepatitis Group. They also allow the distinction between type 1 AIH, characterized by positive anti-nuclear and/or anti-smooth muscle antibody, and type 2 AIH, characterized by positive anti-liver kidney microsomal type 1 and/or anti-liver cytosol type 1 antibody. Anti-soluble liver antigen is the only AIH-specific autoantibody, and is found in 20-30% of both type 1 and type 2 AIH. Anti-neutrophil cytoplasmic antibody is frequently positive in type 1 AIH, being associated also with inflammatory bowel disease and with primary/autoimmune sclerosing cholangitis. The reference method for autoantibody testing remains indirect immunofluorescence on triple tissue (rodent liver, kidney and stomach), allowing both the detection of the majority of liver-relevant reactivities, including those autoantibodies whose molecular target antigens are unknown. Of note, the current knowledge of the clinical significance of autoantibodies relies on studies based on this technique. However, immunofluorescence requires trained laboratory personnel, is observer-dependent, and lacks standardization, leading to ongoing attempts at replacing this method with automated assays, the sensitivity, and specificity of which, however, require further studies before they can be used as a reliable alternative to immunofluorescence; currently, they may be used as complementary to immunofluorescence.

Fab-dimerized glycan-reactive antibodies are a structural category of natural antibodies

Natural antibodies (Abs) can target host glycans on the surface of pathogens. We studied the evolution of glycan-reactive B cells of rhesus macaques and humans using glycosylated HIV-1 envelope (Env) as a model antigen. 2G12 is a broadly neutralizing Ab (bnAb) that targets a conserved glycan patch on Env of geographically diverse HIV-1 strains using a unique heavy-chain (VH) domain-swapped architecture that results in fragment antigen-binding (Fab) dimerization. Here, we describe HIV-1 Env Fab-dimerized glycan (FDG)-reactive bnAbs without VH-swapped domains from simian-human immunodeficiency virus (SHIV)-infected macaques. FDG Abs also recognized cell-surface glycans on diverse pathogens, including yeast and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike. FDG precursors were expanded by glycan-bearing immunogens in macaques and were abundant in HIV-1-naive humans. Moreover, FDG precursors were predominately mutated IgM+IgD+CD27+, thus suggesting that they originated from a pool of antigen-experienced IgM+ or marginal zone B cells.

Antinuclear Autoantibodies in Health: Autoimmunity Is Not a Synonym of Autoimmune Disease

The incidence of autoimmune diseases is increasing. Antinuclear antibody (ANA) testing is a critical tool for their diagnosis. However, ANA prevalence in healthy persons has increased over the last decades, especially among young people. ANA in health occurs in low concentrations, with a prevalence up to 50% in some populations, which demands a cutoff revision. This review deals with the origin and probable physiological or compensatory function of ANA in health, according to the concept of immunological clearance, theory of autoimmune regulation of cell functions, and the concept of functional autoantibodies. Considering ANA titers ≤1:320 as a serological marker of autoimmune diseases seems inappropriate. The role of anti-DFS70/LEDGFp75 autoantibodies is highlighted as a possible anti-risk biomarker for autoimmune rheumatic disorders. ANA prevalence in health is different in various regions due to several underlying causes discussed in the review, all influencing additive combinations according to the concept of the mosaic of autoimmunity. Not only are titers, but also HEp-2 IFA) staining patterns, such as AC-2, important. Accepting autoantibodies as a kind of bioregulator, not only the upper, but also the lower borders of their normal range should be determined; not only their excess, but also a lack of them or "autoimmunodeficiency" could be the reason for disorders.

Influence of PTPN22 Allotypes on Innate and Adaptive Immune Function in Health and Disease

Protein tyrosine phosphatase, non-receptor type 22 (PTPN22) regulates a panoply of leukocyte signaling pathways. A single nucleotide polymorphism (SNP) in PTPN22, rs2476601, is associated with increased risk of Type 1 Diabetes (T1D) and other autoimmune diseases. Over the past decade PTPN22 has been studied intensely in T cell receptor (TCR) and B cell receptor (BCR) signaling. However, the effect of the minor allele on PTPN22 function in TCR signaling is controversial with some reports concluding it has enhanced function and blunts TCR signaling and others reporting it has reduced function and increases TCR signaling. More recently, the core function of PTPN22 as well as functional derangements imparted by the autoimmunity-associated variant allele of PTPN22 have been examined in monocytes, macrophages, dendritic cells, and neutrophils. In this review we will discuss the known functions of PTPN22 in human cells, and we will elaborate on how autoimmunity-associated variants influence these functions across the panoply of immune cells that express PTPN22. Further, we consider currently unresolved questions that require clarification on the role of PTPN22 in immune cell function.

Leukoencephalopathy and cerebral edema as the presenting manifestations of SLE in an ANA-negative adolescent female: a case report and review of literature

BACKGROUND

Systemic lupus erythematosus (SLE) is an autoimmune disease with various clinical manifestations involving multiple organ systems. Neuropsychiatric manifestations of SLE have been associated with increased morbidity and mortality, thus it is important to recognize and diagnose the disease entity and treat early. When neuropsychiatric symptoms are involved, typically there are many other systemic features to aid in the diagnosis of SLE. Many autoantibodies have been discovered and are used to help diagnose SLE. The antibody present in most cases of pediatric SLE, as well as in many other rheumatic diseases, is the nonspecific antinuclear antibody (ANA). The ANA is a commonly used screening tool by primary care physicians when evaluating a patient with a possible rheumatic disorder. However, a small subset of SLE patients, 1-5%, present with a negative ANA, and it is important to keep SLE on the differential diagnosis in specific instances when a thorough infectious, metabolic and neurological workup has been completed and proven to be inconclusive.

CASE PRESENTATION

This case involves a Hispanic adolescent female with a negative ANA who presented with diffuse cerebral edema secondary to leukoencephalopathy due to SLE with central nervous system involvement. She was normotensive on presentation and relatively symptom free aside from headache. She had an extensive workup while inpatient involving metabolic, infectious disease, rheumatology, and neurology prior to obtaining the diagnosis of SLE. She was treated with cyclophosphamide and rituximab with appropriate disease response.

CONCLUSIONS

A review of the literature revealed 12 cases with SLE presenting with or developing diffuse cerebral edema and/or leukoencephalopathy. Our patient's case differs in that she was also ANA negative despite other autoantibody positivity. While she did have low complements and transient leukopenia, she did not present with other signs of organ involvement, which made the diagnosis of SLE with neuropsychiatric involvement quite challenging. We discuss the importance of keeping SLE on the differential diagnosis despite a negative ANA in complex cases after thorough workup has been unrevealing, and to consider initial screening with not only the ANA but also dsDNA and complements to avoid missed diagnoses.

Human platelet lysate efficiency, stability, and optimal heparin concentration required in culture of mammalian cells

Background

Fetal bovine serum (FBS) has been used to support the growth and proliferation of mammalian cells for decades. Owing to several risk factors associated with FBS, several trials have been conducted to evaluate substitutes to FBS with the same efficiency and the lower risk issues.

Methods

In this study, human platelet lysate (HPL) derived from activated human platelets was evaluated as an alternative to FBS due to the associated risk factors. To evaluate the efficiency of the preparation process, platelet count was performed before and after activation. The concentrations of several growth factors and proteins were measured to investigate HPL efficiency. HPL stability was studied at regular intervals, and optimal heparin concentration required to prevent gel formation in various media was determined. The biological activity of HPL and FBS was compared by evaluating the growth performance of Vero and Hep-2 cell lines.

Results

Result of platelet count assay revealed the efficiency of HPL preparation process. Growth factor concentrations in HPL were significantly higher than those in FBS, while the protein content of HPL was lower than that of FBS. Stability study data showed that the prepared HPL was stable for up to 15 months at -20℃. Ideal heparin concentration to be used in different media was dependent on calcium concentration. Results of cell viability assay showed that HPL was superior to FBS in supporting the growth and proliferation of Vero and Hep-2 cells.

Conclusion

The HPL prepared by the mechanical activation of platelets may serve as an efficient alternative to FBS in cell culture process.

Differential expression of antibodies to NMDA receptor in anti-NMDA receptor encephalitis and in neuropsychiatric systemic lupus erythematosus

Objective

Anti-NMDA receptor encephalitis is the most prevalent autoimmune encephalitis having characteristic clinical features with autoantibodies against tetrameric transmembrane channels composed of combinations of NR1 subunits of NMDA receptors with NR2 subunits, which are detected by cell-based assay (anti-NR1/NR2). On the other hand, antibodies against the linear epitope in NR2 subunit (anti-NR2) have been shown to be expressed in patients with diffuse psychiatric/neuropsychological syndromes of neuropsychiatric SLE (diffuse NPSLE). However, it has not been explored whether anti-NR1/NR2 might be detected in NPSLE, nor has it been clear whether anti-NR2 might have cross-reactivity with anti-NR1/NR2. The current study was therefore performed to explore the prevalence of anti-NR1/NR2 in NPSLE.

Methods

Serum specimens were obtained from 31 patients with NPSLE (22 with diffuse NPSLE and 9 with neurological syndromes or polyneuropathy) and from 18 normal healthy subjects. Anti-NR2 and anti-NR1/NR2 were measured by ELISA and cell-based assay, respectively. The positivity for anti-NR2 was defined by a value exceeding mean+2 SD of normal healthy subjects.

Results

Anti-NR2 was positive in the sera of 19 of 31 patients with NPSLE (in 15 of 22 patients with diffuse NPSLE). By contrast, anti-NR1/NR2 was positive only in 2 of 31 patients with NPSLE (in 2 of 22 patients with diffuse SLE). The positivity for anti-NR1/NR2 was not correlated with anti-NR2 values.

Conclusions

These results demonstrate that the prevalence of anti-NR1/NR2 is extremely low in NPSLE. Moreover, the data also confirm that anti-NR2 antibodies do not have cross-reactivity with anti-NR1/NR2.

Neuronal damage and neuroinflammation markers in patients with autoimmune encephalitis and multiple sclerosis

Inflammatory diseases of the central nervous system (CNS) are a diagnostic challenge to clinicians. Autoimmune encephalitis (AE) is an important diagnostic consideration in patients with CNS inflammatory disorders; despite of a wide range of neuropsychiatric symptoms it should be diagnosed as soon as possible and the patient transferred to the neurologist. We studied a group of AE patients (n = 24) as compared to multiple sclerosis (MS, n = 61) and control (n = 19) groups. Detailed clinical pictures of patients are presented. We focused on relevant cerebrospinal fluid (CSF) tests like protein levels, cytosis and oligoclonal bands, neuroinflammation indices (interleukin-6, soluble receptor of IL-6, neopterin, anti-ribosomal proteins antibodies) and markers of neurodegeneration (phosphorylated neurofilament heavy chain, pNfh). Elevated neopterin level was found in AE group as compared to the MS and control groups, while protein and pNfh were increased in both AE and MS groups. In the MS group, the cytosis and soluble receptor of IL-6 were higher as compared to the control group. Anti-ribosomal proteins antibodies were increased in a single patient with AE. High levels of protein were predictive of mortality in AE patients, while IL-6 and pNfh were elevated in severe AE patients. AE patients with paraneoplastic etiology demonstrated oligoclonal bands positivity. Taken together, our results suggest the neopterin as an additional marker of autoimmune brain inflammation. Though higher levels of protein, IL-6 and pNfh were found in patients with severe disease progression and death, prognostic values of these markers should be validated in larger cohorts of patients.

A comprehensive review of Hep-2 cell line in translational research for laryngeal cancer

Cell lines represent an invaluable resource in modern science including basic and translational cancer research. Although there have been warnings over the past half century, the number of publications in the literature that erroneously used "non-existent" cell lines is still growing. For example, the Hep-2 cell line, first described in 1954 as laryngeal cancer cells, was reported as soon as in 1966 to be comprised of cervical adenocarcinoma cells derived via HeLa cell line contamination. Notably, the International Cell Line Authentication Committee (ICLAC) reported Hep-2 to be one among 488 misidentified cell lines, and one of 451 cell lines where no authentic stock is known. However, the number of laryngeal cancer research publications using the Hep-2 cell line has greatly increased over the past three decades. A comprehensive review of Hep-2 cell line misuse has been performed to identify the extent of the problem. 1,036 publications referenced in the MEDLINE database from 1954 to the first of January 2018 referred to the purported laryngeal origin of the Hep-2 cell line, with an increasing trend and with a peak of 93 publications in 2014. The rate of publications that focused on laryngeal cancer topics have increased over the past three decades to reach 80% in 2017. This increase was mainly driven by the remarkable productivity of Chinese researchers, of which English-language publications represented 76% of these articles in 2017. International collaborations and up-to-date national guidelines are needed.

Reference standards for the detection of anti-mitochondrial and anti-rods/rings autoantibodies

Background:

Anti-mitochondrial antibodies (AMA) are found in >90% of primary biliary cholangitis patients. Anti-rods/rings antibodies (anti-RR) are most commonly associated with interferon-α and ribavirin treatment in hepatitis C patients. Clinical laboratories routinely screen for AMA and anti-RR using indirect immunofluorescence on HEp-2 cells (HEp-2-IFA). Therefore, we sought to establish reference materials for use in AMA and anti-RR testing.

Methods:

AMA-positive and anti-RR-positive human plasma samples (AMA-REF and RR-REF), identified as potential reference materials based on preliminary data, were further validated by multiple laboratories using HEp-2-IFA, immunoprecipitation (IP), western blotting, IP-western, line immunoassay (LIA), addressable laser bead immunoassay (ALBIA), and ELISA.

Results:

AMA-REF showed a strong positive cytoplasmic reticular/AMA staining pattern by HEp-2-IFA to ≥1:1280 dilution, and positive signal on rodent kidney/stomach/liver tissue. AMA-REF reacted with E2/E3, E3BP, E1α, and E1β subunits of the pyruvate dehydrogenase complex by IP and western blotting, and was positive for AMA antigens by LIA, ALBIA, and ELISA. RR-REF showed a strong positive rods and rings staining pattern by HEp-2-IFA to ≥1:1280 dilution. RR-REF reacted with inosine monophosphate dehydrogenase by IP, IP-western, and ALBIA. RR-REF also produced a nuclear homogenous staining pattern by HEp-2-IFA, immunoprecipitated proteins associated with anti-U1RNP antibody, and reacted weakly with histones, nucleosomes, Sm, and nRNP/Sm by LIA.

Conclusions:

AMA-REF and RR-REF are useful reference materials for academic or commercial clinical laboratories to calibrate and establish internal reference standards for immunodiagnostic assays. AMA-REF and RR-REF are now available for free distribution to qualified laboratories through Plasma Services Group.

Performance analysis of automated evaluation of Crithidia luciliae-based indirect immunofluorescence tests in a routine setting - strengths and weaknesses

BACKGROUND

Antibodies directed against dsDNA are a highly specific diagnostic marker for the presence of systemic lupus erythematosus and of particular importance in its diagnosis. To assess anti-dsDNA antibodies, the Crithidia luciliae-based indirect immunofluorescence test (CLIFT) is one of the assays considered to be the best choice. To overcome the drawback of subjective result interpretation that inheres indirect immunofluorescence assays in general, automated systems have been introduced into the market during the last years. Among these systems is the EUROPattern Suite, an advanced automated fluorescence microscope equipped with different software packages, capable of automated pattern interpretation and result suggestion for ANA, ANCA and CLIFT analysis.

METHODS

We analyzed the performance of the EUROPattern Suite with its automated fluorescence interpretation for CLIFT in a routine setting, reflecting the everyday life of a diagnostic laboratory. Three hundred and twelve consecutive samples were collected, sent to the Central Diagnostic Laboratory of the Maastricht University Medical Centre with a request for anti-dsDNA analysis over a period of 7 months.

RESULTS

Agreement between EUROPattern assay analysis and the visual read was 93.3%. Sensitivity and specificity were 94.1% and 93.2%, respectively. The EUROPattern Suite performed reliably and greatly supported result interpretation.

CONCLUSIONS

Automated image acquisition is readily performed and automated image classification gives a reliable recommendation for assay evaluation to the operator. The EUROPattern Suite optimizes workflow and contributes to standardization between different operators or laboratories.

Design of a Computer-Assisted System to Automatically Detect Cell Types Using ANA IIF Images for the Diagnosis of Autoimmune Diseases

Indirect immunofluorescence technique applied on HEp-2 cell substrates provides the major screening method to detect ANA patterns in the diagnosis of autoimmune diseases. Currently, the ANA patterns are mostly inspected by experienced physicians to identify abnormal cell patterns. The objective of this study is to design a computer-assisted system to automatically detect cell patterns of IIF images for the diagnosis of autoimmune diseases in the clinical setting. The system simulates the functions of modern flow cytometer and provides the diagnostic reports generated by the system to the technicians and physicians through the radar graphs, box-plots, and tables. The experimental results show that, among the IIF images collected from 17 patients, 6 were classified as coarse-speckled, 3 as diffused, 2 as discrete-speckled, 1 as fine-speckled, 2 as nucleolar, and 3 as peripheral patterns, which were consistent with the patterns determined by the physicians. In addition to recognition of cell patterns, the system also provides the function to automatically generate the report for each patient. The time needed for the whole procedure is less than 30 min, which is more efficient than the manual operation of the physician after inspecting the ANA IIF images. Besides, the system can be easily deployed on many desktop and laptop computers. In conclusion, the designed system, containing functions for automatic detection of ANA cell pattern and generation of diagnostic report, is effective and efficient to assist physicians to diagnose patients with autoimmune diseases. The limitations of the current developed system include (1) only a unique cell pattern was considered for the IIF images collected from a patient, and (2) the cells during the process of mitosis were not adopted for cell classification.

Protein microarrays: a new tool for the study of autoantibodies in immunodeficiency

Autoimmunity is highly coincident with immunodeficiency. In a small but growing number of primary immunodeficiencies, autoantibodies are diagnostic of a given disease and implicated in disease pathogenesis. In order to improve our understanding of the role of autoantibodies in immunodeficiencies and to discover novel autoantibodies, new proteomic tools are needed. Protein microarrays have the ability to screen for reactivity to hundreds to many thousands of unique autoantigens simultaneously on a single chip using minimal serum input. Here, we review different types of protein microarrays and how they can be useful in framing the study of primary and secondary immunodeficiencies.