Antibody Patterns Research Articles

Diagnosing Autoimmune Bullous Diseases—An Indian Perspective

Abstract Introduction: Autoimmune bullous diseases (AIBDs) are a group of illnesses characterized by autoantibodies targeting adhesion molecules in the skin and mucosa. Accurate diagnosis of the specific subtype of AIBD is crucial for effective management and predicting prognosis, especially in cases with an increased risk of malignancy. However, differentiating between subtypes can be challenging due to overlapping symptoms. Overview of diagnostic tests: Direct immunofluorescence microscopy (DIF) detects in vivo bound antibodies in perilesional tissue biopsies and provides details about the probable site of autoantibody deposition within the skin/mucosae, immunoglobulin type, and pattern of antibody deposition. Indirect immunofluorescence (IIF) microscopy with organ substrate is a minimally invasive serological test that detects circulating autoantibodies. Enzyme-linked immunosorbent assay (ELISA) quantifies serum autoantibodies against specific autoantigens. Quantitative ELISA is useful for diagnosis, monitoring therapy, and assessing disease activity. Commercially available ELISA kits, including the multi-variant ones, can detect antibodies associated with AIBDs. BIOCHIP is a technique based on IIF that offers a sensitive and specific diagnostic alternative to ELISA. It uses microarrays with multiple antigenic substrates to simultaneously screen common AIBDs. The BIOCHIP slides contain different substrates, allowing the identification of multiple types of autoantibodies in a single test. Indian context: While these diagnostic tests offer valuable insights into target antigens, antibody patterns, and disease subtypes, it is important to note that the availability of these tests is limited in most centers across India. This limitation can be attributed to factors such as the relatively higher cost of these investigations, challenges related to the stability of immuno-reactants, and a shortage of trained personnel capable of performing such tests. Conclusion: This review discusses the diagnosis of AIBDs based on resources available in India, as of today. It also provides with practically applicable diagnostic algorithms for pragmatic diagnosis of AIBDs in Indian scenario.

De novo granulocyte–macrophage colony-stimulating factor antibody production has been linked to acute graft-versus-host disease following hematopoietic stem cell transplantation from an HLA-matched, unrelated donor

The role of non-HLA antibodies in hematopoietic stem cell transplantation (HSCT) and acute graft-versus-host disease (aGVHD) is not established. Serum samples collected from 58 adult patients before and after HSCT were examined for non-HLA antibodies. Following HSCT, 47 out of 58 patients (81.0 %) had various antibody patterns, with 23 of them (39.7 %) producing denovo antibodies. The most prevalent antibodies were directed against granulocyte–macrophage colony-stimulating factor (GM-CSF). The Fisher exact test revealed a statistically significant correlation between the incidence of acute graft-versus-host disease and denovo production of GM-CSF antibodies in patients fully HLA-matched with their donors (p = 0.001). There were no cases of denovo GM-CSF antibody production seen in non-permissively HLA-mismatched patients. Consequently, we hypothesize that the development of aGVHD after HLA-matched HSCT may differ from that following HLA-mismatched HSCT.

Association between Antinuclear Antibodies Patterns and Immunological Markers with Systemic Lupus Erythematosus in Iraqi Female Patients

Background: Systemic lupus erythematosus is a condition where the immune system attacks various tissues and organs, affecting commonly women between the ages of 15 to 44. It is caused by genetics or environmental factors. A critical factor in the diagnosis by antinuclear antibodies at a level of ≥1:80. Objective: To assess the disease activity and identification of antinuclear antibody patterns and titer on Hep-2 cells with immunological markers. Methods: This was a case-control study conducted at Baghdad Teaching Hospital/Medical City between January 25, 2024, to April 25, 2024. 60 SLE patients were contrasted with 60 healthy controls. The American College of Rheumatology SLE criteria were used to make the diagnosis. Results: SLE patients had a mean age of 32.12±10.54 years, while controls had a mean age of 31.37±10.65 years (P=0.699). positive family history represents 15.0 % while negative family history of SLE patients is 85.0%. The mean disease duration was 5.25±4.77 years. The disease activity index (SLEDI) was (27.80 ±10.40). The most common patterns of Antinuclear Antibodies (ANA) are speckled (56.7%), homogeneous (26.7%), peripheral (1.7%), mixed (3.3%), and negative (11.7%) patterns. Conclusion: Antinuclear antibodies are considered the gold standard diagnostic test. A few healthy individuals display speckled patterns at a ratio of 1:40. The disease activity no significant with pattern.

Application Study of Neutralization Confirmatory Testing for Low Positive Hepatitis B Surface Antigen.

The high sensitivity of HBsAg quantitative tests has led to some challenges in the qualitative interpretation of weakly positive specimens. This study aimed to explore the clinical utility of neutralization confirma-tory testing for specimens with low positive hepatitis B surface antigen (HBsAg). A retrospective analysis was conducted on outpatient and inpatient cases, from January 2021 to January 2022, at the Zhongshan City People's Hospital, Zhongshan. Confirmatory testing as well as enzyme-linked immunosorbent assay (ELISA) was applied to reanalyze 382 samples with low positive HBsAg detected by chemilumi-nescence microparticle immunoassay (CMIA). A retrospective analysis of hepatitis B serum markers, including e-antigen, e-antibody, and core antibody patterns, was also performed. When the HBsAg value ranged from 0.05 - 0.09 IU/mL, the positivity rate of the confirmatory testing was 34.5%. The HBsAg true positivity levels were all between 0.07 and 0.09. In the range of 0.10 - 0.49, the positivity rate of confirmatory testing was 96.1%. The three methods exhibited a high consistency, when testing samples with relatively high HBsAg values. A receiver operating characteristic (ROC) analysis showed that the optimal sensitivity and specificity were achieved at 0.14 IU/mL. For the HBV e-antigen-positive and negative groups, the positivity rate of confirmatory testing was 100% and 93.8%, with no statistical difference between them. For specimens with weakly positive, low-value HBsAg, particularly when the hepatitis B surface an-tigen level is less than 0.14 IU/mL, neutralization confirmatory testing can serve as a means for further confirmation.

High-resolution kinetics and cellular determinants of SARS-CoV-2 antibody response over two years after COVID-19 vaccination

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) studies usually rely on cross-sectional data of large cohorts but limited repeated samples, overlooking significant inter-individual antibody kinetic differences. By combining Luminex, activation-induced marker (AIM) and IFN-γ/IL-2 Fluorospot assays, we characterized the IgM, IgA, and IgG antibody kinetics using 610 samples from 31 healthy adults over two years after COVID-19 vaccination, and the T-cell responses six months post-booster. Antibody trajectories varied among isotypes: IgG decayed slowly, IgA exhibited an initial sharp decline, which gradually slowed down and stabilized above the seropositivity threshold. Contrarily, IgM rapidly dropped to undetectable levels after primary vaccination. Importantly, three vaccine doses induced higher and more durable anti-spike IgG and IgA levels compared to two doses, whereas infection led to the highest antibody peak and slowest antibody decay rate compared to vaccination. Comparing with ancestral virus, antibody levels recognizing Omicron subvariants had a faster antibody decay. Finally, polyfunctional T cells were positively associated with subsequent IgA responses. These results revealed distinctive antibody patterns by isotype and highlight the benefits of booster doses in enhancing and sustaining antibody responses.

Antibody Pattern: Correlation of Age and Gender in ANA and Anti-ds-DNA Prevalence

Antibody Pattern: Correlation of Age and Gender in ANA and Anti-ds-DNA Prevalence

Immunofluorescence Patterns of Antinuclear Antibodies in the Indian Population

Autoimmune diseases are chronic hypersensitive diseases that occur due to an inability of the immune system to recognize self-antigens as part of its system. Antinuclear autoantibodies (ANA) are antibodies that target the proteins located in the nucleus, mitotic spindle, nuclear membrane, and cytoplasmic substructures. Detection of ANA is done using either the ANA-IIF or by ELISA method; the latter might be slightly more sensitive as compared to the ANA-IIF but the specificity is however low. ANA patterns such as nuclear, cytoplasmic, and mitotic can be important to clinical practice because they suggest the significance, as well as the nature of autoimmune Connective Tissue Disorder (CTDs). ANA is a predictor of autoimmune diseases, and the risk is greater in female individuals. The specific objective of this study was to assess the prevalence of ANA and the detection of demographic correlations with them; thereby it would help in the identification of the various autoantibody subclasses in the Indian people. The present cross-sectional descriptive study included 351 patient records from a tertiary care hospital in Kolkata, India expounds on the association of multiple ANA patterns with certain autoantibodies, and demography of the ANA-positive patients. Knowledge of such regional variations of autoimmune diseases would be useful to formulate a strategy for proper diagnosis of systemic autoimmune rheumatic diseases (SARDs) in India.

Influence of AAV vector tropism on long-term expression and Fc-γ receptor binding of an antibody targeting SARS-CoV-2

Long-acting passive immunization strategies are needed to protect immunosuppressed vulnerable groups from infectious diseases. To further explore this concept for COVID-19, we constructed Adeno-associated viral (AAV) vectors encoding the human variable regions of the SARS-CoV-2 neutralizing antibody, TRES6, fused to murine constant regions. An optimized vector construct was packaged in hepatotropic (AAV8) or myotropic (AAVMYO) AAV capsids and injected intravenously into syngeneic TRIANNI-mice. The highest TRES6 serum concentrations (511 µg/ml) were detected 24 weeks after injection of the myotropic vector particles and mean TRES6 serum concentrations remained above 100 µg/ml for at least one year. Anti-drug antibodies or TRES6-specific T cells were not detectable. After injection of the AAV8 particles, vector mRNA was detected in the liver, while the AAVMYO particles led to high vector mRNA levels in the heart and skeletal muscle. The analysis of the Fc-glycosylation pattern of the TRES6 serum antibodies revealed critical differences between the capsids that coincided with different binding activities to murine Fc-γ-receptors. Concomitantly, the vector-based immune prophylaxis led to protection against SARS-CoV-2 infection in K18-hACE2 mice. High and long-lasting expression levels, absence of anti-drug antibodies and favourable Fc-γ-receptor binding activities warrant further exploration of myotropic AAV vector-based delivery of antibodies and other biologicals.

Staining pattern of specific and cross-reacting Melan-A antibodies: A comparative study on 15,840 samples from 133 human tumor types.

The Melan-A (melanocyte antigen) protein, also termed 'melanoma antigen recognized by Tcells 1' (MART-1) is a protein with unknown function whose expression is specific for the melanocyte lineage. Antibodies against Melan-A are thus used for identifying melanocytic tumors, but some Melan-A antibodies show an additional - diagnostically useful - cross-reactivity against an unspecified protein involved in corticosteroid hormone synthesis. To comprehensively compare the staining patterns of a specific and a cross-reactive Melan-A antibody in normal and neoplastic tissues, tissue microarrays containing 15,840 samples from 133 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types were analyzed by immunohistochemistry. For the Melan-A-specific antibody 'Melan-A specific' (MSVA-900M), Melan-A positivity was seen in 96.0% of 25 benign nevi, 93.0% of 40 primary and 86.7% of 75 metastatic melanomas, 82.4% of 85 renal angiomyolipomas as well as 96.4% of 84 neurofibromas, 2.2% of 46 granular cell tumors, 1.0% of 104 schwannomas, and 1.1% of 87 leiomyosarcomas. The cross-reactive antibody 'Melan-A+' (MSVA-901M+) stained 98.1% of the tumors stained by 'Melan-A specific'. In addition, high positivity rates were seen in sex-cord-stroma tumors of the ovary (35.3%-100%) and the testis (86.7%) as well as for adrenocortical neoplasms (76.3%-83.0%). Only nine further tumor groups showed Melan-A+ staining, including five different categories of urothelial carcinomas. Our data provide a comprehensive overview on the staining patterns of specific and cross-reactive Melan-A antibodies. The data demonstrate that both antibodies are highly useful for their specific purpose. It is important for pathologists to distinguish these two Melan-A antibody subtypes for their daily work.

Drug Induced Rowell’s Syndrome: A Rare Presentation

Rowell’s syndrome (RS) is a rare disorder characterized by Erythema multiforme (EM)-like lesions in a patient with lupus erythematosus, either systemic lupus erythematosus (SLE) or cutaneous lupus erythematosus (CLE). A 35 years old female presented in our dermatology outpatient department (OPD) with complaint of hemorrhagic crusting of lips and multiple discrete targetoid lesions over the chest, upper limb, and gluteal region. Investigations revealed a speckled pattern of antinuclear antibody (ANA), anti-Smith antibody, anti-ds DNA antibody, and strongly positive anti-Ro antibody. According to the clinical evaluation and investigations, the diagnosis of drug induced RS was made. The likely role of proton pump inhibitors, namely esomeprazole as a triggering factor is discussed. After stopping esomeprazole and starting medications with oral steroids and hydroxychloroquine, her good response to treatment was noted.

Myositis-associated antibodies predict the severity of lung involvement in adult patients with inflammatory myositis - a cohort study of 70 adult patients with myositis in a single center.

Idiopathic inflammatory myopathies (IIMs) encompass a diverse group of diseases characterized by considerable variability in clinical manifestations, antibody profiles, and responsiveness to immunosuppressive therapies. This study aimed to investigate the association between organ involvement and distinct myositis autoantibodies in individuals with IIM in a single-center cohort. Patients with ICD diagnoses M33.1, M33.2, M33.9, or M609 who (1) had been tested with Euroline blot assay for myositis autoantibodies and (2) met the classification criteria of definite/probable polymyositis (PM) or dermatomyositis (DM), anti-synthetase syndrome (ASS), or inclusion body myositis (IBM) were included. Medical journals were retrospectively examined with respect to clinical disease features. Seventy patients (median age 58 years; 66% females) were included and represented the following diagnosis: PM (n = 23), DM (n = 21), ASS (n = 23), and IBM (n = 3). Most of the patients (87%) presented a muscle biopsy indicative of myositis. The presence of autoantibodies was as follows: myositis-specific antibodies, MSA (n = 53), myositis-associated antibodies, MAA (n = 33), both MSA + MAA (n = 24), MSA only (n = 29), MAA only (n = 9), no MSA, or MAA (n = 8). Anti-Jo-1 was the most common MSA (19%), whereas the most common MAA was anti-Ro/SSA52 (31%). We observed a significant association between antibody patterns and lung disease. In our cohort, 47% of the patients in the whole study group, 86% of patients with anti-SSA52, and 100% with anti-Jo-1 had pulmonary involvement. Patients with both MSA and MAA had a higher incidence of lung disease and decreased CO-diffusion capacity. This was especially prominent in anti-Ro/SSA52-positive patients. Interestingly, none of the patients suffered from lung disease if only antibodies against Mi-2α, Mi-2β, NXP2, HMGCR, and TIF1γ were present or no MSA/MAA were detected. The simultaneous presence of both MAA and MSA indicates an increased risk of lung involvement in patients with inflammatory myopathies. The presence of any MAA, and especially anti-Ro/SSA52, is associated with more severe pulmonary disease. Our data suggest that MAA antibodies might be relevant markers for early detection and treatment of lung involvement in IIM.

Hepatitis E Virus Infection in Voluntary Blood Donors in the Russian Federation.

Transfusion-transmitted hepatitis E virus (HEV) infection is an increasing concern in many countries. We investigated the detection rate of HEV viremia in blood donors in Russia. A total of 20,405 regular repetitive voluntary non-renumerated blood donors from two regions (Moscow and Belgorod) were screened for HEV RNA using the cobas® HEV test in mini-pools of six plasma samples. Samples from each reactive pool were tested individually. The average HEV RNA prevalence was 0.024% (95% CI: 0.01-0.05%), or 1 case per 4081 donations. No statistically significant differences in HEV RNA prevalence were observed between the two study regions. The PCR threshold cycle (Ct) values ranged from 25.0 to 40.5 in reactive pools, and from 20.9 to 41.4 in reactive plasma samples when tested individually. The HEV viremic donors had different antibody patterns. Two donor samples were reactive for both anti-HEV IgM and IgG antibodies, one sample was reactive for anti-HEV IgM and negative for anti-HEV IgG, and two samples were seronegative. At follow-up testing 6 months later, on average, four donors available for follow-up had become negative for HEV RNA and positive for anti-HEV IgG. The HEV ORF2 sequence belonging to HEV-3 sub-genotype 3a was obtained from one donor sample. The sequencing failed in the other four samples from viremic donors, presumably due to the low viral load. In conclusion, the HEV RNA detection rate in blood donors in Russia corresponds with data from other European countries, including those that implemented universal donor HEV screening. These data support the implementation of HEV RNA donor screening to reduce the risk of transfusion-transmitted HEV infection in Russia.

Durability of COVID-19 humoral immunity post infection and different SARS-COV-2 vaccines

BackgroundThe global challenge posed by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has been a major concern for the healthcare sector in recent years. Healthcare workers have a relatively high risk of encountering COVID-19 patients, making protective immunity against SARS-CoV-2 is a priority for them. This study aims to evaluate the longitudinal measurement of SARS-CoV-2 IgG spike protein antibodies in healthcare workers (HCWs) after COVID-19 infection and after receiving the first and second doses of SARS-CoV-2 vaccines, including Pfizer-BioNTech (BNT162b2) and Oxford-AstraZeneca (AZD1222). MethodsThis longitudinal cohort study involved 311 healthcare workers working in two tertiary hospitals in Saudi Arabia. All participants were followed between July 2020 and July 2022 after completing the study questionnaire. A total of 3 ml of the blood samples were collected at four intervals: before/after vaccination. ResultsHCWs post-infection had lower mean SARS-CoV-2 IgG levels three months post-infection than post-vaccination. 92.2% had positive IgG levels two weeks after the first dose and reached 100% after the second dose. Over 98% had positive antibodies nine months after the second dose, regardless of vaccine type. The number of neutralizing antibodies decreased and was around 50% at nine months after the second dose. ConclusionThe results show different antibody patterns between infected and vaccinated HCWs. A high proportion of participants had positive antibodies after vaccination, with high levels persisting nine months after the second dose. Neutralizing antibodies decreased over time, with only about 50% of participants having positive antibodies nine months after the second dose. These results contribute to our understanding of immunity in healthcare workers and highlight the need for the continuous monitoring and possible booster strategies.

Frequency of Immunofluorescence Antinuclear Antibody Patterns: In A Local Population from North India

Frequency of Immunofluorescence Antinuclear Antibody Patterns: In A Local Population from North India

The spectrum of neutralizing and non-neutralizing anti-FVIII antibodies in a nationwide cohort of 788 persons with hemophilia A.

Anti-factor VIII (FVIII) antibodies have been reported to exhibit both neutralizing and non-neutralizing characteristics. This is the first study investigating the full spectrum of FVIII-specific antibodies, including non-neutralizing antibodies, very-low titer inhibitors, and inhibitors, in a large nationwide population of persons with hemophilia A of all severities. All persons with hemophilia A (mild (FVIII > 5-40 IU/dL)/moderate [FVIII 1-5 IU/dL)/severe (FVIII < 1 IU/dL)] with an available plasma sample who participated in the sixth Hemophilia in the Netherlands study between 2018 and 2019 were included. The presence of anti-FVIII antibodies of the immunoglobulin A, M, and G isotypes and IgG subclasses, along with antibody titer levels, were assessed using direct-binding ELISAs. FVIII specificity was assessed using a competition-based ELISA approach. The inhibitor status was determined using the Nijmegen ultra-sensitive Bethesda assay (NusBA) and the Nijmegen Bethesda assay (NBA). In total, 788 persons with hemophilia A (336 (42.6%) mild, 123 (15.6%) moderate, 329 (41.8%) severe hemophilia) were included. The median age was 45 years (IQR 24-60), and the majority (50.9%) had over 150 exposure days to FVIII concentrates. Within our population, 144 (18.3%) individuals had non-neutralizing FVIII-specific antibodies, 10 (1.3%) had very low-titer inhibitors (NusBA positive; NBA negative), and 13 (1.6%) had inhibitors (both NusBA and NBA positive). IgG1 was the most abundant FVIII-specific antibody subclass, and the highest titer levels were found for IgG4. In individuals without a reported history of inhibitor development, no clear differences were observed in antibody patterns between those who were minimally or highly exposed to FVIII concentrates. IgG4 subclass antibodies were only observed in persons with a reported history of FVIII inhibitor or in those with a currently detected (very low-titer) inhibitor. In this cross-sectional study, we identified non-neutralizing antibodies in a relatively large proportion of persons with hemophilia A. In contrast, in our population, consisting of persons highly exposed to FVIII concentrates, (very low-titer) inhibitors were detected only in a small proportion of persons, reflecting a well-tolerized population. Hence, our findings suggest that only a small subpopulation of non-neutralizing FVIII-specific antibodies is associated with clinically relevant inhibitors.

Investigating the Seroconversion Patterns of Specific Antibodies Against Various Antigens of SARS-CoV-2 in Hospitalized COVID-19 Patients and Vaccinated Individuals

Background: Inducing a humoral response to SARS-CoV-2 may partially control virus dissemination. However, there is a lack of consistency in the reported kinetics of IgM and IgG responses to SARS-CoV-2. Additionally, the humoral response to SARS-CoV-2 may differ from that elicited by vaccination. Therefore, we were motivated to evaluate the kinetics of antibodies against SARS-CoV-2 in both infected and vaccinated individuals. Objectives: This study aimed to investigate the seroconversion patterns of specific antibodies against various antigens of SARS-CoV-2 in hospitalized COVID-19 patients and vaccinated individuals, focusing specifically on comparing the humoral responses elicited by infection and vaccination. Methods: Serial blood and swab samples were collected from 134 COVID-19 patients at six time points following admission. Real-time RT-PCR specific for SARS-CoV-2, as well as anti-SARS-CoV-2 IgM and IgG, were tested using ELISA. Additionally, 141 serum samples were obtained from vaccinated individuals. Anti-SARS-CoV-2 spike and RBD IgGs, along with neutralizing antibodies (NAs), were assessed using ELISA in both the vaccinated group and 96 COVID-19 patients. Results: Anti-SARS-CoV-2 IgM was found positive in 23.3% of patients at 0 - 7 days after symptom onset, with seropositivity increasing to 71.7% at 15 - 21 days. Subsequently, IgM positivity gradually decreased to 62.7% at &gt; 28 days post-symptom onset. Meanwhile, anti-SARS-CoV-2 IgG was positive in 28.3% of patients at 0 -7 days, rising to 83.7% at 22 - 28 days after symptom onset, and remained constant thereafter. Anti-spike and RBD IgGs, along with NAs, were detected in 89.7%, 87.4%, and 87.9% of vaccinated individuals, respectively, and in 37.5%, 32.3%, and 32.3% of COVID-19 patients, respectively. There was a significant correlation between anti-spike IgG and anti-RBD IgG levels and NAs in both COVID-19-infected and vaccinated individuals. The mean concentrations of anti-spike and RBD IgGs were higher in vaccinated individuals with a history of COVID-19 infection compared to those without prior infection. Conclusions: The antibody profile for IgM and IgG against SARS-CoV-2 suggests that as time passes after the onset of disease symptoms, the seropositivity in COVID-19 patients increases. Furthermore, antibodies against SARS-CoV-2 are produced more efficiently through COVID-19 vaccination than natural infection.

Levamisole-Adulterated Cocaine-Induced Mucous Membrane Pemphigoid: Case Reports and Literature Review.

The aim of this study was to report 2 cases of levamisole-adulterated cocaine-induced mucous membrane pemphigoid. This study is a review of case reports and literature. Two patients presented with bilateral severe purulent conjunctivitis, corneal ulceration, and rapidly progressive forniceal shortening. Both patients were active cocaine users. A complete blood analysis showed a positive antineutrophil cytoplasmic antibody immunofluorescence with a mixed perinuclear antineutrophil cytoplasmic antibody and cytoplasmic-staining antineutrophil cytoplasmic antibody pattern. Direct immunofluorescence examination of conjunctival tissue showed linear deposition of component 3 and immunoglobulins at the basal membrane. A diagnosis of levamisole-adulterated cocaine-induced mucous membrane pemphigoid was made. In case 1, this suspicion was confirmed by investigating remnants of cocaine on the patient's debit card using mass spectrometry, which contained traces of levamisole. In both cases, aggressive immunosuppressive therapy combining systemic corticosteroids and rituximab was able to control the disease. However, by the time these therapies were initiated, significant corneal injury had occurred requiring corneal grafts in both patients. Given the rising abuse of cocaine, it is important that ophthalmologists are made aware of its association with severe atypical cicatricial conjunctivitis. To the best of our knowledge, we present the first case proving the causal relationship between levamisole and ocular cicatricial pemphigoid.

Recognition of rare antinuclear antibody patterns based on a novel attention-based enhancement framework.

Rare antinuclear antibody (ANA) pattern recognition has been a widely applied technology for routine ANA screening in clinical laboratories. In recent years, the application of deep learning methods in recognizing ANA patterns has witnessed remarkable advancements. However, the majority of studies in this field have primarily focused on the classification of the most common ANA patterns, while another subset has concentrated on the detection of mitotic metaphase cells. To date, no prior research has been specifically dedicated to the identification of rare ANA patterns. In the present paper, we introduce a novel attention-based enhancement framework, which was designed for the recognition of rare ANA patterns in ANA-indirect immunofluorescence images. More specifically, we selected the algorithm with the best performance as our target detection network by conducting comparative experiments. We then further developed and enhanced the chosen algorithm through a series of optimizations. Then, attention mechanism was introduced to facilitate neural networks in expediting the learning process, extracting more essential and distinctive features for the target features that belong to the specific patterns. The proposed approach has helped to obtained high precision rate of 86.40%, 82.75% recall, 84.24% F1 score and 84.64% mean average precision for a 9-category rare ANA pattern detection task on our dataset. Finally, we evaluated the potential of the model as medical technologist assistant and observed that the technologist's performance improved after referring to the results of the model prediction. These promising results highlighted its potential as an efficient and reliable tool to assist medical technologists in their clinical practice.

Retrospective analysis of the clinical significance of Ro52/TRIM21 antibody and specific antinuclear antibody patterns by indirect immunofluorescence.

To determine the clinical significance of Ro52 protein/tripartite motif-containing 21 antibody and specific antinuclear antibody patterns using indirect immunofluorescence technique. The retrospective study was conducted at the clinical laboratory of the First Affiliated Hospital of Chongqing Medical University, China, and comprised data from January 2017 to December 2021 of patients who underwent antinuclear antibody and anti-extractable nuclear antigen antibody detection. Inpatients with Ro52 antibody-positive status were taken as the cases, while anti-Ro52 negative patients with clear clinical diagnosis were taken as the controls. Data was analysed using SPSS 19. There were 1802 cases and 1211 controls. Positive Ro52 showed significantly greater frequency in patients with primary Sjogren's syndrome, systemic lupus erythematosus, inflammatory myositis, dry eyes and interstitial lung disease (p<0.05). Ro52 antibody showed high positive predictive value for primary Sjogren's syndrome 25(96.15%), systemic lupus erythematosus 259(91.20%), connective tissue disease-associated interstitial lung disease 45(86.67%) and inflammatory myositis 60(86.67%). Antinuclear antibody indirect immunofluorescence patterns most frequently detected were nuclear speckled 128(40.89%) and cytoplasmic speckled 126(40.26%) (p<0.05). Interstitial lung disease was associated with the presence of cytoplasmic speckled antinuclear antibody indirect immunofluorescence pattern 24(19.2%), while tumours 47(36.5%) and hepatitis B 26(20.3%) seemed to be more frequent with nuclear speckled pattern (p<0.05). The simultaneous reactivity extractable nuclear antigen antibodies most frequently detected were antinuclear antibody+Ro52+anti-Sjogren's syndrome A+ 558(33.96%). Ro52 antibody positivity was found to be associated with Sjogren's syndrome, systemic lupus erythematosus, inflammatory myositis, dry eye and interstitial lung disease. The antinuclear antibody immunofluorescence pattern of Ro52 positive was single and primarily granular cytoplasm type. Antinuclear antibody negative and Ro52 positive in the serum of patients also had certain significance in auxiliary disease diagnosis.

Complex patterns on HEp-2 indirect immunofluorescence assay in a large sample referred for anti-cell autoantibodies detection.

The combination of patterns is a frequent and challenging situation in the daily laboratory routine of autoantibodies testing using HEp-2 cells indirect immunofluorescence assay (HEp-2-IFA). Recently, the Brazilian Consensus on Autoantibodies (BCA) named these combinations as complex patterns (CPs) and organized them into 3 subtypes: multiple, mixed, and composite. This study aimed to describe the most frequent combinations of HEp-2-IIF patterns according to this new nomenclature. Routine HEp-2-IFA results reported in January and June 2017 were reviewed using the new BCA classification. Visual pattern recognition was performed by experts on HEp-2-IFA readings, using the International Consensus on Antinuclear Antibodies (ANA) Patterns (ICAP) and BCA recommendations. 54,990 serum samples from different patients were tested for ANA-HEp-2, and 11,478 (20.9%) were positive at a titer ≥ 1/80. Among these positive samples, 1,111 (9.7%) displayed CPs, divided into 95 different combinations. A higher proportion of CPs was observed in the pediatric age group. Multiple, mixed, and composite patterns were present in 85.3, 5.4, and 9.5% of the samples, respectively. In the multiple/mixed pattern group (n=1,005), double, triple, and quadruple combinations (ICAP/BCA codes) were observed in 97.7%, 2.2%, and 0.1%, respectively. The double nuclear pattern was the most prevalent combination observed (67.6%). The most common CPs registered were AC-4 (nuclear fine speckled) + AC-6,7 (nuclear discrete dots) (n=264); AC-2 (nuclear dense fine speckled) + AC-6,7 (n=201); AC-4+AC-8,9,10 (nucleolar) (n=129); and AC-3 (centromere)+AC-4 (n=124). All of these combinations were in the multiple subgroup. Almost 10% of positive results in the HEp-2 procedure displayed CPs. Among the 3 subtypes of CPs proposed, the multiple pattern was the most prevalent, especially in the pediatric population. The AC-4, AC-2, and AC-6,7 were the most prevalent single patterns observed in the combinations described in this study. There was a significant association between age and the prevalence of most combined patterns. The AC-4+AC-6,7 combination was the most prevalent complex pattern detected regardless of the age group. The AC-2+AC-6,7 was more prevalent in younger individuals. The concepts involved in the CPs definition should add value to the reading and interpretation of the HEp-2-IIF assay.