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Introduction: Haemolytic Disease of the Foetus and Newborn (HDFN) is widely known to be caused by the presence of irregular Red Blood Cell (RBC) antibodies in pregnant females. To prevent HDFN, it is crucial to identify these antibodies in pregnant women. Aim: To evaluate the prevalence of irregular red cell antibodies in pregnant women in a tertiary care hospital. Materials and Methods: A cross-sectional retrospective study was conducted in the Department of Transfusion Medicine at Indraprastha Apollo New Delhi, from November 2009 to December 2017. A total of 8,217 prenatal females were examined for irregular red cell antibodies. Antibody screening and blood grouping were performed. The Capture-R ready screen was used to confirm screen-positive tests. Adsorption, elution, and other advanced techniques were utilised as needed. Data was collected from patient records and entered into a Microsoft excel spreadsheet. The statistical analysis was conducted using Statistical Package for Social Sciences (SPSS) software version 14.0 (USA). Statistical tests, including the Chi-squared and Fisher’s exact test, were performed, with a p-value less than 0.05 considered statistically significant. Results: Out of the 8,217 prenatal females examined, 105 (1.27%) had positive screening results with the four cell panel. Red cell alloimmunisation was observed in groups that were RhD negative (n=93/105; 88.57%) and positive (n=12/105; 11.42%). The most prevalent alloantibody among RhD negative individuals was alloantibody anti-D (n= 83/93; 89.24%), followed by alloantibody anti C+ anti D (n=13/93; 13.97%). Anti-D was the most prevalent alloantibody overall (n=83/105; 79.04%). Conclusion: Alloimmunisation rates were notably high among women lacking the Rh D antigen. Individuals with a history of adverse obstetric outcomes showed a statistically significant association with alloimmunisation. Therefore, it is recommended to screen such individuals for alloantibodies to enable early detection and improve the management of HDFN.

Unexpected red blood cell antibodies refer to antibodies except for anti-A and anti-B in normal ABO blood group, and are widely present in patients with pregnancy, transfusion, transplantation, injection of immunogenic substances, or autoimmune diseases, leading to difficulties in blood type identification and cross matching test, which seriously affect transfusion safety and efficacy. This consensus aims to further standardize the requirements, operating procedures and clinical significance of antibody screening, thus improving the safety and efficacy of blood transfusion.

BACKGROUND: For the management of hemolytic disease of the fetus and newborn (HDFN), it is important to detect unexpected red cell antibody in pregnant women. We assessed the prevalence of unexpected red cell antibodies in consecutive pregnant women attending antenatal clinic (ANC). More importantly, cases with unexpected antibody causing severe anemia were followed-up for intervention (Intra-uterine transfusion {IUT}) and outcome of pregnancy (still-birth/live-healthy). AIMS AND OBJECTIVES: The study was conducted with an objective to find the prevalence of unexpected RBC antibodies in pregnant women, their specificity and to do the follow-up for IUT and outcome of pregnancy (still-birth, live-birth) in antibody positive women. MATERIALS AND METHODS: This was a prospective study from January 2021 to May 2022 at two tertiary care centres. All antenatal samples received by the laboratory were screened for unexpected red cell antibody. Whenever antibody screen was positive, antibody identification was performed. Patients, positive for unexpected antibody and anemia were followed up for any transfusion-based intervention and outcome of pregnancy. RESULTS: A total of 539 consecutive samples were worked up and among these, 10 samples (1.85%) were found to be antibody positive. The antibodies identified were Anti-D (n=6), anti-Leb (n=1), anti-M (n=1), anti-C (n=1) and anti-E (n=1).The prevalence of unexpected antibodies in Rh positive and Rh negative pregnant women was 0.83% and 10.9% respectively. Follow-up was done for all 10 cases with unexpected antibody and anemia was monitored by MCA PSV (middle cerebral artery peak systolic velocity).Two women developed severe anemia thus requiring single intrauterine transfusion (at 26 weeks and 28 weeks respectively) each, for correction of anemia. In both these cases, healthy male child was delivered. At 3-month follow-up both children were alive and healthy. CONCLUSION: The study found prevalence of unexpected RBC antibodies in pregnant women as 1.85%. The study also underlined importance of transfusion-based interventions contributing to successful outcome in couple of cases with severe anemia.

Objective To investigate the differential diagnosis of 1 anti-C, e alloantibodies combined with anti-e, Jkb mimicking alloantibodies by absorption-elution test and titer integral method. Methods ABO, Rh and Kidd blood group antigens were identified by tube method. Two sets of panel cells were used for antibody screening and antibody specificity identification by saline method, polyamine method and microcolumn gel method.The antibody was further confirmed by multiple absorption-elution tests and titer integral method. RHCE and JK gene were sequenced by multiple PCR. Results Serological gene sequencing analysis showed that the ABO blood group of the patient was A type with Rh subtype ccDEE and was positive for direct antiglobulin test (DAT). Multiple absorption-elution tests and titer integral method demonstrated that the serum of the patient contained anti-C, e alloantibodies along with anti-e, Jkb mimicking autoantibodies and there were anti-e, Jkb mimicking autoantibodies on red blood cells(RBCs). According to gene sequencing analysis, there was G>C at exon 676 of the RHCE gene, and the remaining exons were not mutated, suggesting that the RHCE phenotype was ccEE. The 838 G/A heterozygote of exon 9 in JK gene, Jk blood group phenotype was Jk (a+ b+ ). Cross matched type A ccDEE and Jk(a+ b-) RBCs were transfused, and no adverse reactions occurred. Conclusion Serology combined with molecular biology to identify the phenotype of the patient′s RBCs, absorption-elution test and titer integral method to identify the antibody of the patient′s serum can detect the alloantibody type, thus providing strategies for targeted blood transfusion.

Integrins are cell surface receptors that mediate the interactions of cells with their surroundings and play essential roles in cell adhesion, migration, and homeostasis. Eight of the 24 integrins bind to the tripeptide Arg-Gly-Asp (RGD) motif in their extracellular ligands, comprising the RGD-binding integrin subfamily. Despite similarity in recognizing the RGD motif and some redundancy, these integrins can selectively recognize RGD-containing ligands to fulfill specific functions in cellular processes. Antibodies against individual RGD-binding integrins are desirable for investigating their specific functions, and were selected here from a synthetic yeast-displayed Fab library. We discovered 11 antibodies that exhibit high specificity and affinity toward their target integrins, i.e. αVβ3, αVβ5, αVβ6, αVβ8, and α5β1. Of these, six are function-blocking antibodies and contain a ligand-mimetic R(G/L/T)D motif in their CDR3 sequences. We report antibody-binding specificity, kinetics, and binding affinity for purified integrin ectodomains, as well as intact integrins on the cell surface. We further used these antibodies to reveal binding preferences of the αV subunit for its 5 β-subunit partners: β6 = β8 > β3 > β1 = β5.

The rapid development of vaccines is a crucial objective in modern biotechnology and molecular pharmacology. In this context, conducting research to expedite the selection of a potent immunogen is imperative. The candidate vaccine should induce the production of antibodies that can recognize the immunogenic epitopes of the target protein, resembling the ones found in recovered patients. One major challenge in vaccine development is the absence of straightforward and reliable techniques to determine the extent to which the spectrum of antibodies produced after vaccination corresponds to antibodies found after recovery. This paper describes a newly developed method to detect antibodies specific to immunogenic epitopes of the target protein in blood plasma and to compare them with antibody spectra generated post vaccination. Comparing the antibody pool generated in the human body after recovering from an infectious disease with the pool formed through vaccination can become a universal method for screening candidate vaccines. This method will enable the identification of candidate vaccines that can induce the production of antibodies similar to those generated in response to a natural infection. Implementing this approach will facilitate the rapid development of new vaccines, even when faced with a pandemic. [ABSTRACT FROM AUTHOR]

The development of monoclonal antibodies (mAbs) represents a significant milestone in both basic research and clinical applications due to their target specificity and versatility in therapeutic and diagnostic applications. The innovative strategy of mAb screening, utilizing phage display, facilitates the in vitro screening of antibodies with high affinity to target antigens. The single-chain variable fragment (scFv) is a subset of mAb derivatives, known for its high binding affinity and smaller size—just one-third of that of human IgG. This report outlines a detailed and comprehensive procedure for constructing a scFv phagemid library derived from human patients, followed by screening via phage display affinity selection. The protocol utilizes 348 primer combinations spanning the entire human antibody repertoire to minimize sequence bias and maintain library diversity during polymerase chain reaction (PCR) for scFv generation, resulting in a library size greater than 1 × 108. Furthermore, we describe a high-throughput phage display screening protocol using enzyme-linked immunosorbent assay (ELISA) to evaluate more than 1200 scFv candidates. The generation of a highly diverse scFv library, coupled with the implementation of a phage display screening methodology, is expected to provide a valuable resource for researchers in pursuit of scFvs with high affinity for target antigens, thus advancing both research and clinical endeavors. [ABSTRACT FROM AUTHOR]

Objective With advancements in minimally invasive techniques, the use of spinal fusion surgery is rapidly increasing and transfusion rates are decreasing. Routine preoperative ABO/Rh blood type and antibody screening (T&S) laboratory tests may not be appropriate for all spinal fusion patients. Herein, we constructed a nomogram to assess patient transfusion risk based on various risk factors in patients undergoing spinal fusion surgery, so that preoperative T&S testing can be selectively scheduled in appropriate patients to reduce healthcare and patient costs. Methods Patients who underwent spinal fusion surgery between 01/2020 and 03/2023 were retrospectively examined and classified into the training (n = 3533, 70%) and validation (n = 1515, 30%) datasets. LASSO and multivariable logistic regression were used to analyze risk factors for blood transfusion. Nomogram predictive model was built according to the independent predictors and mode predictive power was validated using consistency index (C‐index), Hosmer–Lemeshow (HL) test, calibration curve analysis and area under the curve (AUC) for receiver operating characteristic (ROC) curve. Bootstrap resampling was used for internal validation. Decision curve analysis (DCA) was applied to evaluate the model's performance in the clinic. Results Being female, age, BMI, admission route, critical patient, operative time, heart failure, end‐stage renal disease or chronic kidney disease (ESRD or CKD), anemia, and coagulation defect were predictors of blood transfusion for spinal fusion. A prediction nomogram was developed according to a multivariate model with good discriminatory power (C‐index = 0.887); Bootstrap resampling internal validation C‐index was 0.883. Calibration curves showed strong matching between the predicted and actual probabilities of the training and validation sets. HL tests for the training and validation sets had p‐values of 0.327 and 0.179, respectively, indicating good calibration. When applied to the training set, the following parameters were found: AUC: 0.895, 95% CI: 0.871–0.919, sensitivity 78.2%, specificity 86.7%, positive predictive value 29.4% and negative predictive value 98.2%. If the model were applied in the training set, 2911 T&S tests (82.4%) would be eliminated, equaling a RMB349,320 cost reduction. The AUC in the internal validation was: 0.879, 95% CI: 0.839–0.927, sensitivity 75.2%, specificity 88.8%, positive predictive value 34.3%, negative predictive value 97.9%, would eliminate 1276 T&S tests (84.2%), saving RMB 153,120. The DCA curve indicated good clinical application value. Conclusion The nomogram based on 10 independent factors can help healthcare professionals predict the risk of transfusion for patients undergoing spinal fusion surgery to target preoperative T&S testing to appropriate patients and reduce healthcare costs.

Objective: With advancements in minimally invasive techniques, the use of spinal fusion surgery is rapidly increasing and transfusion rates are decreasing. Routine preoperative ABO/Rh blood type and antibody screening (T&S) laboratory tests may not be appropriate for all spinal fusion patients. Herein, we constructed a nomogram to assess patient transfusion risk based on various risk factors in patients undergoing spinal fusion surgery, so that preoperative T&S testing can be selectively scheduled in appropriate patients to reduce healthcare and patient costs. Methods: Patients who underwent spinal fusion surgery between 01/2020 and 03/2023 were retrospectively examined and classified into the training (n = 3533, 70%) and validation (n = 1515, 30%) datasets. LASSO and multivariable logistic regression were used to analyze risk factors for blood transfusion. Nomogram predictive model was built according to the independent predictors and mode predictive power was validated using consistency index (C‐index), Hosmer–Lemeshow (HL) test, calibration curve analysis and area under the curve (AUC) for receiver operating characteristic (ROC) curve. Bootstrap resampling was used for internal validation. Decision curve analysis (DCA) was applied to evaluate the model's performance in the clinic. Results: Being female, age, BMI, admission route, critical patient, operative time, heart failure, end‐stage renal disease or chronic kidney disease (ESRD or CKD), anemia, and coagulation defect were predictors of blood transfusion for spinal fusion. A prediction nomogram was developed according to a multivariate model with good discriminatory power (C‐index = 0.887); Bootstrap resampling internal validation C‐index was 0.883. Calibration curves showed strong matching between the predicted and actual probabilities of the training and validation sets. HL tests for the training and validation sets had p‐values of 0.327 and 0.179, respectively, indicating good calibration. When applied to the training set, the following parameters were found: AUC: 0.895, 95% CI: 0.871–0.919, sensitivity 78.2%, specificity 86.7%, positive predictive value 29.4% and negative predictive value 98.2%. If the model were applied in the training set, 2911 T&S tests (82.4%) would be eliminated, equaling a RMB349,320 cost reduction. The AUC in the internal validation was: 0.879, 95% CI: 0.839–0.927, sensitivity 75.2%, specificity 88.8%, positive predictive value 34.3%, negative predictive value 97.9%, would eliminate 1276 T&S tests (84.2%), saving RMB 153,120. The DCA curve indicated good clinical application value. Conclusion: The nomogram based on 10 independent factors can help healthcare professionals predict the risk of transfusion for patients undergoing spinal fusion surgery to target preoperative T&S testing to appropriate patients and reduce healthcare costs. [ABSTRACT FROM AUTHOR]

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Background and Objectives: Screening for red blood cell alloantibodies (RBC‐Ab) is a critical step in ensuring blood transfusion safety performed by blood donation screening laboratories. We aim to evaluate the prevalence of the RBC‐Ab among healthy blood donors. Materials and Methods: Antibody screening of serum of all voluntary blood donors was performed as a routine immune‐haematological procedure by a solid‐phase method on a fully automated immunohaematology analyser. Positive sera were further investigated to identify the specificity of RBC‐Ab by a commercially available red cell panel. Results: Between January 2012 and December 2021, a total of 212,218 donations were screened for the presence of RBC‐Ab, 74% from male donors (n = 157,898) and 26% from female donors (n = 54,320). Mean age at donation time was 32 ± 12 years. A total of 1007 donations were screened positive (0.47%), and 131 were confirmed positive for alloantibodies in their serum, yielding a prevalence of 0.06% (95% confidence interval: 0.05–0.07). Most frequent alloantibodies identified were of RH blood group system (64%), followed by anti‐MNS (19%), anti‐Kidd and Lewis (6% each) and anti‐KEL (4%). The results showed a statistically higher prevalence of alloantibodies in women than men. Our results showed a lower prevalence as compared to the available data, which might be related to our study population. Conclusion: The prevalence of positive antibody screening in healthy donors in this study was found to be 0.47%, while the prevalence of alloantibodies was 0.06%. The most common alloantibodies were anti‐RH1 (25%) and anti‐RH3 (24%). [ABSTRACT FROM AUTHOR]

The Rh-D negative pregnancy is commonly associated with alloimmunization against D-antigen. It can be prevented by anti-D prophylaxis in pregnant patients with negative results on antibody screening. Hence, it is essential to exclude alloantibody-D in the presence of multiple alloantibodies. Anti-G antibody is formed after exposure to G antigen in neonate RBCs. Blood-group discrepancy was noted in reverse grouping, and antibody-screening results were positive in our case individual, a 28-year old Odiya Indian woman. We performed antibody identification on serum specimens from this patient, which revealed the pattern of anti-D + anti-C antibody specificity. Blood-group discrepancy was solved using rr (ce/ce)–phenotype pooled cells for reverse grouping. We identified anti-G antibodies by themselves without anti-D and anti-C after performing sequential adsorption of serum with rʹrʹ (Ce/Ce) and R2R2 (DcE/DcE) group-O RBCs in the mother, who had rr phenotype and primigravida designation. After completing antibody screening at the first antenatal check-up, we recommended prophylactic anti-D for the mother in any future pregnancies she may have. [ABSTRACT FROM AUTHOR]

Introduction: Blood transfusion remains the primary modality of treatment for many serious and common diseases. According to the International Society of Blood Transfusion (ISBT), there are about 349 blood group antigens, out of which only about 25-28 antigens are known to cause acute or delayed type of haemolytic transfusion reactions which could be prevented by Pretransfusion Testing (PTT). Regulated pretransfusion tests include ABO blood grouping, Rh typing, antibody detection, antibody identification and compatibility testing. The purpose of compatibility tests is to demonstrate invitro red cell antigen-antibody reaction. The Antihuman Globulin (AHG) crossmatch testing can assure ABO compatibility between donor and patient blood as well as detect most clinically significant antibodies. Type and Screen (T&S) is a procedure carried out as part of PTT in which the recipient’s blood sample is tested for ABO group, RhD T&S for unexpected antibodies. Aim: To compare T&S method of PTT with AHG crossmatch. Materials and Methods: This cross-sectional study was conducted in the department of Transfusion medicine at Government Royapettah Hospital, Chennai and The Tamil Nadu Dr. MGR Medical University, Chennai, Tamil Nadu, India from June 2012 to December 2013. T&S was performed on 1,040 recipients’ (510 males and 530 females) samples. All these samples were subjected to AHG crossmatch with ABO group and RhD type matched donor samples to assess the compatibility between donor and recipient by using column agglutination technology. Statistical analysis was carried out using Statistical Package for the Social Sciences (SPSS) version 11.0. Results: The prevalence of unexpected antibodies in the recipient population was 1.06%. Among the 1,040 recipients’ blood samples, 11 samples were found to have unexpected antibodies. Out of these 11 samples, 10 showed exact antibodies and the remaining one sample with negative antibody screening was found to be incompatible with AHG crossmatch. The sensitivity and specificity of T&S method in comparison to AHG crossmatch was 87.50% and 99.71%, respectively. Conclusion: The sensitivity and specificity of T&S is as acceptable as AHG crossmatch. However, in view of one sample with false negative antibody screening in the study population, it is imperative to know the phenotyping of Red Blood Cells (RBC) antigens of the native population before getting away with AHG crossmatch.

ABSTRACTPrior research has generated a vast amount of antibody sequences, which has allowed the pre-training of language models on amino acid sequences to improve the efficiency of antibody screening and optimization. However, compared to those for proteins, there are fewer pre-trained language models available for antibody sequences. Additionally, existing pre-trained models solely rely on embedding representations using amino acids or k-mers, which do not explicitly take into account the role of secondary structure features. Here, we present a new pre-trained model called BERT2DAb. This model incorporates secondary structure information based on self-attention to learn representations of antibody sequences. Our model achieves state-of-the-art performance on three downstream tasks, including two antigen-antibody binding classification tasks (precision: 85.15%/94.86%; recall:87.41%/86.15%) and one antigen-antibody complex mutation binding free energy prediction task (Pearson correlation coefficient: 0.77). Moreover, we propose a novel method to analyze the relationship between attention weights and contact states of pairs of subsequences in tertiary structures. This enhances the interpretability of BERT2DAb. Overall, our model demonstrates strong potential for improving antibody screening and design through downstream applications.

The rapid development of vaccines is a crucial objective in modern biotechnology and molecular pharmacology. In this context, conducting research to expedite the selection of a potent immunogen is imperative. The candidate vaccine should induce the production of antibodies that can recognize the immunogenic epitopes of the target protein, resembling the ones found in recovered patients. One major challenge in vaccine development is the absence of straightforward and reliable techniques to determine the extent to which the spectrum of antibodies produced after vaccination corresponds to antibodies found after recovery. This paper describes a newly developed method to detect antibodies specific to immunogenic epitopes of the target protein in blood plasma and to compare them with antibody spectra generated post vaccination. Comparing the antibody pool generated in the human body after recovering from an infectious disease with the pool formed through vaccination can become a universal method for screening candidate vaccines. This method will enable the identification of candidate vaccines that can induce the production of antibodies similar to those generated in response to a natural infection. Implementing this approach will facilitate the rapid development of new vaccines, even when faced with a pandemic.

The development of monoclonal antibodies (mAbs) represents a significant milestone in both basic research and clinical applications due to their target specificity and versatility in therapeutic and diagnostic applications. The innovative strategy of mAb screening, utilizing phage display, facilitates the in vitro screening of antibodies with high affinity to target antigens. The single-chain variable fragment (scFv) is a subset of mAb derivatives, known for its high binding affinity and smaller size—just one-third of that of human IgG. This report outlines a detailed and comprehensive procedure for constructing a scFv phagemid library derived from human patients, followed by screening via phage display affinity selection. The protocol utilizes 348 primer combinations spanning the entire human antibody repertoire to minimize sequence bias and maintain library diversity during polymerase chain reaction (PCR) for scFv generation, resulting in a library size greater than 1 × 108. Furthermore, we describe a high-throughput phage display screening protocol using enzyme-linked immunosorbent assay (ELISA) to evaluate more than 1200 scFv candidates. The generation of a highly diverse scFv library, coupled with the implementation of a phage display screening methodology, is expected to provide a valuable resource for researchers in pursuit of scFvs with high affinity for target antigens, thus advancing both research and clinical endeavors.

Yersinia pestis is a gram-negative bacterium that causes plague in animals and humans. Depending on the route of disease transmission, the bacterium can cause an acute, often fatal disease that has a narrow window for treatment with antibiotics. Additionally, antibiotic resistant strains have been identified, emphasizing the need for novel treatments. Antibody therapy is an appealing option that can direct the immune system to clear bacterial infections. Advances in biotechnology have made both engineering and producing antibodies easier and more affordable. In this study, two screening assays were optimized to evaluate the ability of antibodies to promote phagocytosis of Y. pestis by macrophages and to induce a cytokine signature in vitro that may be predictive of protection in vivo. We evaluated a panel of 21 mouse monoclonal antibodies targeting either the anti-phagocytic capsule F1 protein or the LcrV antigen, which is part of the type 3 secretion system that facilitates translocation of virulence factors into the host cell, using two functional assays. Anti-F1 and anti-LcrV monoclonal antibodies both increased bacterial uptake by macrophages, with greater uptake observed in the presence of antibodies that were protective in the mouse pneumonic plague model. In addition, the protective anti-F1 and anti-LcrV antibodies produced unique cytokine signatures that were also associated with in vivo protection. These antibody-dependent characteristics from in vitro functional assays will be useful in down-selecting efficacious novel antibodies that can be used for treatment of plague.

Talaromycosis is a fungal infection that generally affects immunocompromised hosts and is one of the most frequent systemic mycoses in HIV patients, especially in endemic areas such as Southeast Asia. Talaromyces marneffei, the causative agent of talaromycosis, grows as a mold in the environment but adapts to the human body and host niches by transitioning from conidia to yeast-like cells. Knowledge of the human host and T. marneffei interaction has a direct impact on the diagnosis, yet studies are still lacking. The morbidity and mortality rates are high in taloromycosis patients if the diagnosis and treatments are delayed. Immunogenic proteins are excellent candidates for developing detection tools. Previously, we identified antigenic proteins that were recognized by antibodies from talaromycosis sera. Three of these identified proteins have been previously characterized in detail, while the others have not been explored. To expedite the progress of antigen discovery, the complete list of antigenic proteins and their features was fully reported in this study. Functional annotation and Gene Ontology examination revealed that these proteins showed a high association with membrane trafficking. Further bioinformatics analyses were performed to search for antigenic protein characteristics, including functional domains, critical residues, subcellular localization, secretory signals, and epitope peptide sequences. Expression profiling of these antigenic encoding genes was investigated using quantitative real-time PCR. The results demonstrated that most genes were expressed at low levels in the mold form, but were highly upregulated in the pathogenic yeast phase, consistent with the antigenic role of these genes during the human-host interaction. Most transcripts accumulated in the conidia, suggesting a role during phase transition. The collection of all antigen-encoding DNA sequences described here is freely accessible at GenBank, which could be useful for the research community to develop into biomarkers, diagnostic tests, research detection tools, and even vaccines. [ABSTRACT FROM AUTHOR]

Background and Objectives: The procedure of blood ordering is a major issue in hospitals. Hence, maximum surgical blood ordering schedule is recommended to manage the blood application process properly. The aim of this study was to evaluate the demand and rate of blood consumption in different wards of a pediatric hospital. Methods: This is a cross-sectional on patients ≤18 years old who underwent major surgical procedures from 2015 to 2019. Data included type of department, number of total blood bags requested as well as cross-matched and transfused units. Furthermore, indices such as cross-matched to transfusion (Cross-matched to Transfused (C/T) ratio) in various hospital departments and months were calculated. Results: This study revealed that the utilization rate was 77.29% of blood units among a total of 97356 cases done. The emergency department consumed only 28.08% of its requests. C/T ratio for all departments of the hospital was 1.34. The most and lowest numbers of requests were for surgery 2 department and newborn intensive care unit, respectively. Furthermore, we have observed the lowest rate of C/T ratio in December. Conclusions: Our data showed that in the majority of elective pediatric surgical procedures, a large number of blood units tested for antibody screening were consumed, reducing the consumption of cord blood bags as well as the financial burden for the hospital and the patients. Furthermore, our findings revealed that based on the calculated C/T ratio, the hospital used the correct procedure for blood requests in period of 1 year. In addition, the time for preparation of blood was decreased dramatically. [ABSTRACT FROM AUTHOR]

Background and Objectives: The procedure of blood ordering is a major issue in hospitals. Hence, maximum surgical blood ordering schedule is recommended to manage the blood application process properly. The aim of this study was to evaluate the demand and rate of blood consumption in different wards of a pediatric hospital. Methods: This is a cross-sectional on patients ≤18 years old who underwent major surgical procedures from 2015 to 2019. Data included type of department, number of total blood bags requested as well as cross-matched and transfused units. Furthermore, indices such as cross-matched to transfusion (Cross-matched to Transfused (C/T) ratio) in various hospital departments and months were calculated. Results: This study revealed that the utilization rate was 77.29% of blood units among a total of 97356 cases done. The emergency department consumed only 28.08% of its requests. C/T ratio for all departments of the hospital was 1.34. The most and lowest numbers of requests were for surgery 2 department and newborn intensive care unit, respectively. Furthermore, we have observed the lowest rate of C/T ratio in December. Conclusions: Our data showed that in the majority of elective pediatric surgical procedures, a large number of blood units tested for antibody screening were consumed, reducing the consumption of cord blood bags as well as the financial burden for the hospital and the patients. Furthermore, our findings revealed that based on the calculated C/T ratio, the hospital used the correct procedure for blood requests in period of 1 year. In addition, the time for preparation of blood was decreased dramatically.

Certain pre-transfusion tests are not commonly performed during emergency blood transfusion. In this study, we reviewed and analyzed the data of post-blood transfusion antibody screening tests to establish the effects of unexpected antibodies causing hemolytic transfusion reactions. We reviewed information published domestically and internationally, and selected the data of 68,602 antibody screening tests and 528 antibody identification tests conducted at P hospital. We found that unexpected antibody positive (1198,1.74%), Rh type (161, 30.49%), Lewis type (67, 12.69%), others (Di (a), 28, 5.30%). The anti-E type positive was 93 (17.61%), and that of the cases with anti-C (13, 2.46%). Only data of domestic cases were included for analysis that were published before 2007, which established the presence of antibodies of the following types and numbers of cases: anti-E (196, 22.45%), anti-Le a (82, 9.39%), and anti-E+C (60, 6.87%). In 2018, anti-E (107, 17.12%), anti-E+C (56, 8.96%), and anti-Di a (28, 4.48%) were detected. In other domestic cases, S hospital was detect to anti-E, anti-Le a, anti-E+C. The Anti-E, anti-D, anti-E+C, and anti-C+E were detected in D hospital. In Saudi Arabia, Anti-D, anti-E, and anti-Jka was detected. The Anti-M, Anti-N, Anti-Le (a), and Anti-D were detected in India. Requests for emergency blood transfusion increased 1.8 times after the opening of the trauma center. This study has the disadvantage of being a cross-sectional study. additional studies are needed to provide basic information on alternative treatments that can increase the safety and reduce the side effects of hemolytic transfusion in emergency transfusion situations.

Blood transfusion is an important and crucial component of adult and pediatric patient care across all medical and surgical disciplines. One of the complications of blood transfusion that commonly confounds the blood transfusion service is the formation of alloantibodies and autoantibodies against red blood cell antigens. We hereby report a case of 31 years old female who developed multiple rhesus alloantibodies; anti-C and anti-e due to a previous history of transfusion, and she underwent a surgical procedure that required blood transfusion. This patient also has a very rare rhesus D-positive phenotype. The aim of reporting this case is to highlight the important role of transfusion medicine services in the early detection of antibodies in individuals with a history of multiple blood transfusions. [ABSTRACT FROM AUTHOR]

Talaromycosis is a fungal infection that generally affects immunocompromised hosts and is one of the most frequent systemic mycoses in HIV patients, especially in endemic areas such as Southeast Asia. Talaromyces marneffei, the causative agent of talaromycosis, grows as a mold in the environment but adapts to the human body and host niches by transitioning from conidia to yeast-like cells. Knowledge of the human host and T. marneffei interaction has a direct impact on the diagnosis, yet studies are still lacking. The morbidity and mortality rates are high in taloromycosis patients if the diagnosis and treatments are delayed. Immunogenic proteins are excellent candidates for developing detection tools. Previously, we identified antigenic proteins that were recognized by antibodies from talaromycosis sera. Three of these identified proteins have been previously characterized in detail, while the others have not been explored. To expedite the progress of antigen discovery, the complete list of antigenic proteins and their features was fully reported in this study. Functional annotation and Gene Ontology examination revealed that these proteins showed a high association with membrane trafficking. Further bioinformatics analyses were performed to search for antigenic protein characteristics, including functional domains, critical residues, subcellular localization, secretory signals, and epitope peptide sequences. Expression profiling of these antigenic encoding genes was investigated using quantitative real-time PCR. The results demonstrated that most genes were expressed at low levels in the mold form, but were highly upregulated in the pathogenic yeast phase, consistent with the antigenic role of these genes during the human-host interaction. Most transcripts accumulated in the conidia, suggesting a role during phase transition. The collection of all antigen-encoding DNA sequences described here is freely accessible at GenBank, which could be useful for the research community to develop into biomarkers, diagnostic tests, research detection tools, and even vaccines.

The ideal way to screen for the presence of alloantibodies is by antibody screening panels which represent all clinically significant antigens in appropriate dosage. Most centers use pooled O-cells for antibody screening as it has antigens of non-ABO blood group systems that are prevalent in a representative population. Pooled O-cells sometimes fail to detect antibodies to less prevalent red blood cell antigens with reduced expression or show a dosage phenomenon. Despite pooling 4 to 5, O-donor segments, sometimes, it is difficult to detect clinically significant antibodies. False-negative indirect Coombs test by pooled O-cells may delay getting a compatible unit for elective cases where type and screen policy is used. Donor units with weak antigenic expression or units showing dosage can come compatible despite being antigen positive and lead to a hemolytic reaction. We report two cases where antibody screening by pooled O-cells was negative; still, cross-match was incompatible. Antibody screening with a three-cell panel was positive. Antibody identification with 11-cell panels confirmed the alloantibody to be anti-E. The present cases emphasize the importance of three-cell panels over pooled O-cells.

CONTEXT: Alloimmunization by foreign red cell antigens is a matter of concern as it may lead to hemolysis in transfused patients as well as fetus of pregnant females. AIMS: This study aimed to perform a comparative analysis of prevalence and type of irregular antibodies in healthy donors, vis-a-vis blood transfusion recipients. SETTINGS AND DESIGN: Blood samples of 4000 individuals comprising healthy donors, exposed patients, and nonexposed patients were collected and were analyzed for irregular antibodies. MATERIALS AND METHODS: Commercially available three-cell antigen panel was used for the antibody screening. The samples positive in antibody screen were further subjected to an extended 11-cell panel for antibody identification in low-ionic strength saline with and without enzyme. STATISTICAL ANALYSIS: Statistical analysis was done using SPSS for Windows 15.0 program. Chi-square test was used for detecting statistical significance of exposure to red blood cell antigens in the formation of alloantibodies. RESULTS: Of the 4000 samples, antibodies were identified in 105 (2.6%) samples. Overall, nonexposed group showed a seropositivity of 0.36%, while the exposed group showed a seropositivity of 9.4%. Anti-D was the most common antibody found in 38 patients (33.3%). Anti-E was the most common antibody in males, while anti-D was the most common antibody in females. CONCLUSIONS: Since the risk of alloimmunization is more common in multitransfused patients, it is advisable to screen at least those cases for irregular antibodies.

Introduction: Anti-Cw is a low-frequency antibody against Cw (Rh8) antigen, a low incidence antigen of the Rh system. Anti-Cw antibody may cause mild to moderate hemolytic disease of the fetus and newborn (HDFN) and mild to severe immediate or delayed hemolytic transfusion reactions (HTR). The antigenic frequency of Cw in the Indian population is 1.25%. Two cases of Anti-Cw antibody are being reported which were detected during routine antibody screening, one an oncology patient and the other a healthy blood donor. Case 1: A 30-year-old male, known case of acute myeloid leukemia, with previous history of induction chemotherapy and blood transfusion was admitted for further management and chemotherapy. When three cell antibody screening was performed using an automated platform, the screen was positive with +2 reactions. Antibody identification using 14 cells suggested the presence of an Anti-Cw antibody. On further testing, the patient red blood cell (RBCs) were negative for Cw antigen. Case 2: A 20-year-old male, first-time, voluntary blood donor, with no history of blood transfusion donated whole blood. On performing three cell antibody screening using automated platform, screen was found to be positive with +3 reactions. Antibody identification performed using 14 cell panel suggested the presence of Anti-Cw antibody. On further testing, the donor RBCs were negative for Cw antigen. Conclusion: Antibody screening and identification is recommended in pretransfusion testing, especially in multi-transfused patients and patients belonging to the reproductive age group, so that antibody to low-frequency antigen can be detected and its potential to cause HTR and HDFN can be assessed.

Background and Objectives: Although unexpected antibody screening is mandatory according to the Food and Drug Administration and National Blood Policy, the prevalence of irregular red cell antibody and its specificities are not much reported in the donor population of western India. The objective of this study is to find the prevalence of unexpected antibodies in healthy blood donor population of western India. Methods: This is a retrospective study conducted in one of the largest stand-alone blood centers in western India. Data were retrieved from the Integrated Blood Bank Management System (powered by the blood center located in Ahmedabad) software. The data were analyzed for a period of 24 months, from March 1, 2019, to March 31, 2021. Unexpected antibody screening of all voluntary healthy blood donors was performed with fully automated blood grouping equipment Immucor NEO and Diagast EVO using commercial Capture-R Ready Indicator Red Cells (Immucor, USA) and Hemascreen Pool (Diagast, France). Further antibody identification was performed with 11 cell panels. Results: A total of 53,724 volunteer blood donors donated at our blood center during the study period comprised 51,185 (95.27%) male donors and 2539 (4.72%) female donors. A total of 25 (0.046%) donors showed the presence of unexpected antibodies. Most frequent alloantibodies were anti-M (n = 4, 16%) and multiple antibody (n = 4, 16%). Conclusion: Implementation of unexpected antibody screening in all the healthy blood donors routinely and identification of antibodies in antibody screen-positive donors helped us to understand the prevalence of antibodies in our region and its importance in providing compatible blood components which are devoid of irregular antibodies and to avoid delayed transfusion reactions.

Objective To analyze the safety of homotypic transfusion in military donors with negative unexpected antibody. Methods Blood samples (4 mL/person)of eligible military blood donors from November 2018 to October 2019 in our hospital (also working as forces blood station) were conducted for RBC antigen typing, unexpected antibody screening, direct antiglobulin test and cross-match test using microcolumn gel technology, and the compatibility of homotype blood samples was statistical analyzed. Results A total of 1 577 samples from eligible military blood donors were collected, including A RhD (+ ), B RhD (+ ), O RhD (+ ) and AB RhD (+ ), accounting for 31.39% (495/1 577), 34.37% (542/1 577), 24.10% (380/1 577) and 10.15% (160/1 577), respectively. Six samples presenting positive unexpected antibodies (0.38%, 6/1 577) were screened out, and a total of 7 141 cross-matching tests were performed on 1 571 unexpected antibody negative samples, including A RhD (+ ) [37.36% (2 668/7 141)], B RhD (+ ) [34.81% (2 486/7 141)], O RhD (+ ) [17.71% (1265/7 141)] and AB RhD (+ ) [10.11% (722/7 141)]. There was only 1 case of incompatible cross-matching presented between other donors and clinical patients, and the direct antiglobulin test was 1+ , therefore suspended red blood cells of the donor were scrapped. Conclusion There was high compatibility and good security of homotype transfusion of military blood donors with negative unexpected antibody.

Red blood cell (RBC) alloimmunization which is the production of antibodies in response to foreign red cell antigen(s) may occur through exposure to cells or tissues from a genetically different member of same species via transfusion, transplantation or pregnancy. It may cause hemolytic disease of fetus and newborn (HDFN). Usually the incidence of HDFN due to irregular erythrocyte antibody is rare in primigravida. Here we report a primigravida pregnant woman who developed multiple alloantibodies and the neonate developed severe HDFN. A 36-year-old primigravida pregnant woman who had no history of significant medical issues except surgery done for severe endometriosis 1 year back and she had no history of previous blood transfusion presented to us for delivery. The antibody screening came out to be positive with a reaction in cell I and cell II of the antibody screening panel. Further, a mixture of anti D + anti C + anti E alloantibodies were identified using 16 cells panel, select cells and red cell phenotyping. The neonate developed severe HDFN which was managed with phototherapy, exchange transfusion and IvIg. There was no exposure history for sensitization except bleeding in early 2nd trimester. There was a significant discrepancy among mother, father and neonate Rh phenotype which was resolved with clinical history of Invitro fertilization (IVF) with sperm donation. This index case illustrates the need of antibody screening in primigravida antenatal women specially for Rh D negative high risk cases. It also shows importance of Rh Kell typing in sperm donors for future transfusion support of the child. [ABSTRACT FROM AUTHOR]

Objective The development of antibodies against red blood cell (RBC) antigens is one of the most significant adverse effects of chronic blood transfusions. This study aimed to estimate the frequency and causes of RBC immunization in patients with major thalassemia. Methods The findings could help determine the limitation of current practices and help future developments in the selection of suitable blood units for the transfusion support of patients with thalassemia. Results The alloimmunization rate was detected in 52 of 650 patients with major thalassemia (8%). The most frequent antibodies were against K (50%), D (26%), and E (15.4%). Sex, age, and splenectomy did not have any impact on the immunization rate. Immunization was lower in patients who had received only leuko-reduced blood units. Conclusion It is recommended that antibody screening before the first transfusion and extended RBC matching particularly for the most frequent antigens (ABO/Rh/Kell) should be performed for patients with thalassemia. [ABSTRACT FROM AUTHOR]

The ideal way to screen for the presence of alloantibodies is by antibody screening panels which represent all clinically significant antigens in appropriate dosage. Most centers use pooled O-cells for antibody screening as it has antigens of non-ABO blood group systems that are prevalent in a representative population. Pooled O-cells sometimes fail to detect antibodies to less prevalent red blood cell antigens with reduced expression or show a dosage phenomenon. Despite pooling 4 to 5, O‑donor segments, sometimes, it is difficult to detect clinically significant antibodies. False-negative indirect Coombs test by pooled O-cells may delay getting a compatible unit for elective cases where type and screen policy is used. Donor units with weak antigenic expression or units showing dosage can come compatible despite being antigen positive and lead to a hemolytic reaction. We report two cases where antibody screening by pooled O-cells was negative; still, cross-match was incompatible. Antibody screening with a three-cell panel was positive. Antibody identification with 11‑cell panels confirmed the alloantibody to be anti-E. The present cases emphasize the importance of three-cell panels over pooled O-cells. [ABSTRACT FROM AUTHOR]

CONTEXT: Alloimmunization by foreign red cell antigens is a matter of concern as it may lead to hemolysis in transfused patients as well as fetus of pregnant females. AIMS: This study aimed to perform a comparative analysis of prevalence and type of irregular antibodies in healthy donors, vis-a-vis blood transfusion recipients. SETTINGS AND DESIGN: Blood samples of 4000 individuals comprising healthy donors, exposed patients, and nonexposed patients were collected and were analyzed for irregular antibodies. MATERIALS AND METHODS: Commercially available three-cell antigen panel was used for the antibody screening. The samples positive in antibody screen were further subjected to an extended 11-cell panel for antibody identification in low-ionic strength saline with and without enzyme. STATISTICAL ANALYSIS: Statistical analysis was done using SPSS for Windows 15.0 program. Chi-square test was used for detecting statistical significance of exposure to red blood cell antigens in the formation of alloantibodies. RESULTS: Of the 4000 samples, antibodies were identified in 105 (2.6%) samples. Overall, nonexposed group showed a seropositivity of 0.36%, while the exposed group showed a seropositivity of 9.4%. Anti-D was the most common antibody found in 38 patients (33.3%). Anti-E was the most common antibody in males, while anti-D was the most common antibody in females. CONCLUSIONS: Since the risk of alloimmunization is more common in multitransfused patients, it is advisable to screen at least those cases for irregular antibodies. [ABSTRACT FROM AUTHOR]

Introduction: Anti-Cw is a low-frequency antibody against Cw (Rh8) antigen, a low incidence antigen of the Rh system. Anti-Cw antibody may cause mild to moderate hemolytic disease of the fetus and newborn (HDFN) and mild to severe immediate or delayed hemolytic transfusion reactions (HTR). The antigenic frequency of Cw in the Indian population is 1.25%. Two cases of Anti-Cw antibody are being reported which were detected during routine antibody screening, one an oncology patient and the other a healthy blood donor. Case 1: A 30-year-old male, known case of acute myeloid leukemia, with previous history of induction chemotherapy and blood transfusion was admitted for further management and chemotherapy. When three cell antibody screening was performed using an automated platform, the screen was positive with +2 reactions. Antibody identification using 14 cells suggested the presence of an Anti-Cw antibody. On further testing, the patient red blood cell (RBCs) were negative for Cw antigen. Case 2: A 20-year-old male, first-time, voluntary blood donor, with no history of blood transfusion donated whole blood. On performing three cell antibody screening using automated platform, screen was found to be positive with +3 reactions. Antibody identification performed using 14 cell panel suggested the presence of Anti-Cw antibody. On further testing, the donor RBCs were negative for Cw antigen. Conclusion: Antibody screening and identification is recommended in pretransfusion testing, especially in multi-transfused patients and patients belonging to the reproductive age group, so that antibody to low-frequency antigen can be detected and its potential to cause HTR and HDFN can be assessed. [ABSTRACT FROM AUTHOR]

Background and Objectives: Although unexpected antibody screening is mandatory according to the Food and Drug Administration and National Blood Policy, the prevalence of irregular red cell antibody and its specificities are not much reported in the donor population of western India. The objective of this study is to find the prevalence of unexpected antibodies in healthy blood donor population of western India. Methods: This is a retrospective study conducted in one of the largest stand-alone blood centers in western India. Data were retrieved from the Integrated Blood Bank Management System (powered by the blood center located in Ahmedabad) software. The data were analyzed for a period of 24 months, from March 1, 2019, to March 31, 2021. Unexpected antibody screening of all voluntary healthy blood donors was performed with fully automated blood grouping equipment Immucor NEO and Diagast EVO using commercial Capture-R Ready Indicator Red Cells (Immucor, USA) and Hemascreen Pool (Diagast, France). Further antibody identification was performed with 11 cell panels. Results: A total of 53,724 volunteer blood donors donated at our blood center during the study period comprised 51,185 (95.27%) male donors and 2539 (4.72%) female donors. A total of 25 (0.046%) donors showed the presence of unexpected antibodies. Most frequent alloantibodies were anti-M (n = 4, 16%) and multiple antibody (n = 4, 16%). Conclusion: Implementation of unexpected antibody screening in all the healthy blood donors routinely and identification of antibodies in antibody screen-positive donors helped us to understand the prevalence of antibodies in our region and its importance in providing compatible blood components which are devoid of irregular antibodies and to avoid delayed transfusion reactions. [ABSTRACT FROM AUTHOR]

Background. The detection of clinically significant antibodies to red blood cell antigens is important for the selection of compatible blood for patients. The conventional test tube technique (CTT) is commonly used as the gold standard test, but manual testing and visual detection of hemagglutination may produce errors. A more recently developed method, the column agglutination technique (CAT), facilitates ease of testing. Objectives. To investigate the specificity and sensitivity of the CAT compared to the CTT for the screening of clinically significant antibodies from the Rh blood group. Materials and methods. Standard antibodies to the Rh blood group, anti-D, -C and -E, were used as examples of clinically significant antibodies in transfusion science. The antibodies were serially diluted by twofold, then reacted with screening cells with different antigen expression. The hemagglutination reaction was investigated using both techniques, and the grades and scores of the reactions were used to analyze the sensitivity and specificity of the CTT and CAT. Results. The CAT had a better sensitivity than the CTT. The lowest antibody dilution of 1:8192 could be detected using CAT, while a dilution of only 1:2048 could be detected with CTT. However, the CTT and CAT were equal in specificity. The 2 techniques specifically detected all antibodies to the screening cells. Conclusions. Both the CAT and CTT showed 100% specificity. However, the CAT exhibited more sensitivity than the CTT, and can be used in substitution of, or in parallel with, the CTT technique for red blood cell phenotyping, antibody screening, identification, and crossmatching. [ABSTRACT FROM AUTHOR]

The D-/-phenotype is a rare variant of the Rh system, in which red blood cells express only D antigen. Sensitized D-/-women carry a risk of hemolytic disease of fetus and newborn (HDFN) and pose a challenge in management due to nonavailability of antigen negative blood for intra-uterine/exchange-transfusion. A 23y old G2P1L1A0, blood group “A” Rh D+C-c-E-e- presented at 20 weeks' period of gestation (POG) with a positive indirect antiglobulin test. Cordocentesis at 23 weeks' POG revealed fetal's blood group as “B” Rh D+, Direct Coombs Test 4+, Hemoglobin 2.8 g/dL. USG with MCA-PSV indicated rapid development of fetal anemia and hydrops. Patient's sibling had D-/-phenotype, but was ABO-incompatible with the fetus. Rapidity of progression of case resulted in intrauterine fetal demise at 27 weeks' POG. HDFN, in rare blood groups, leads to problems in arranging compatible units in developing countries due to lack of centralized rare donor registries.

Objectives: Detection of maternal irregular antibodies against red blood cell antigen is vital in the management of hemolytic disease of fetus and newborn. There are no uniform guidelines related to antenatal antibody screening and identification in the developing Country like India. This study was aimed to identify such alloimmunization and its associations. Materials and Methods: This prospective study was conducted on antenatal mothers at a tertiary care center. The mothers having a history of anti-D administration, blood transfusion, and autoimmune disorders were excluded from the study. Initial indirect antiglobulin test (IAT) was performed in all blood samples by conventional tube technique (CTT) to identify alloimmunization. IAT-positive samples were screened for irregular antibody by column agglutination technology (CAT). Antibody screen-positive samples were further analyzed in 11-cell panel by CAT. Antibody strength was measured by serial double dilution by CTT. The source of isoimmunization was identified by extended Rh phenotype of women, husband, and newborn. Results: A total of 12 (2.3%) women out of 530 were positive for IAT and antibody screen. Antibody could be identified in 11 women, of which anti-D (5) was the most common, followed by anti-C + anti-D (4), anti-C + anti-E (1), and anti-C (1). All four cases of anti-D + anti-C were distinguished from anti-G by differential adsorption and elution. There was a significant association with alloimmunization versus increased gravid status, antepartum hemorrhage, and past history of newborns with neonatal jaundice. Conclusion: All pregnant women with history of antepartum haemorrhage, newborn with neonatal jundice should be screened for alloantibody for early detection and better management of HDFN.

Background and Objectives: Crossmatching is one of the bases of pretransfusion testing. Resolving problems in crossmatching should be carried out after proper planning and following departmental guidelines, and hence that time is not wasted, or blood withheld from patient unnecessarily. The aim of this study was to find the prevalence and cause of incompatible crossmatch and to formulate root cause analysis to help ensure safe transfusion. Materials and Methods: This was a prospective study conducted at a tertiary care hospital in North India, from December 2018 to November 2019. Request for blood components was received along with 2 ml labeled sample in ethylenediaminetetraacetic acid and plain tube. Crossmatching was done by column agglutination method in polyspecific (IgG + C3d) bead cards by ortho clinical diagnostic using semi-automated biovue. In case of any incompatible result, it was resolved using appropriate steps. Results: During the study period from December 2018 to November 2019, only 67 (0.65%) of the 10,320 samples received were found to be crossmatch incompatible and evaluated and appropriate donor units issued. The crossmatch incompatibility was much higher in the females (46, 68.7%) than the males (21, 31.3%). The direct antiglobulin test (DAT) was positive in nine patient samples, and the indirect antiglobulin test was found positive in 37 incompatible crossmatch units. Eleven cases of incompatible crossmatch were due to wrong blood in tube, seven due to contamination of reagents, and three due to DAT-positive donor units. Conclusion: In this study, alloimmunization (55.2%) was the most prevalent cause of incompatible crossmatch, and the most common alloantibody identified was anti-E. Incompatible crossmatch poses a challenge in the field of transfusion medicine. Root cause analysis is a systemic method for identifying all the contributing factors to a problem, so that the corrective action can be taken. A logical stepwise approach will enable the provision of safe transfusion.

A positive direct antiglobulin test is a criterion for the diagnosis of systemic lupus erythematosus (SLE). In general, severe hemolysis is absent in SLE. Sometimes, these patients may show hemolysis when presenting with antiphospholipid syndrome (APS). It is essential to exclude an underlying alloantibody along with autoantibody. We had reported a case of a 24-year-old female SLE along with an APS patient requiring transfusion support with underlying allo-anti-S antibody. We provided two units of S antigen-negative best-matched units to the patient who tolerated it well and showed improvement.

Introduction: Daratumumab, a monoclonal antibody targeting CD38, is approved to treat multiple myeloma. Red blood cells express low levels of CD38, which can result in a false-positive antibody screen in daratumumab-treated patients. Educational materials were developed to inform healthcare professionals (HCPs) and blood transfusion management department personnel (BTMDP) about this risk and recommended measures to mitigate that risk. Materials were distributed in European countries where daratumumab was commercially available. This post-authorization safety study was designed to evaluate whether HCPs and BTMDP understood the materials.Methods: An anonymous, cross-sectional, non-interventional, web-based survey was distributed in 12 European countries. Four key questions were identified, for which a correct answer from at least 80% of respondents was considered indicative of satisfactory effectiveness.Results: A total of 408 participants completed the questionnaires (62.3% (n = 254) HCPs and 37.7% (n = 154) BTMDP). Responses were consistent between groups. All respondents were aware of the educational materials (the first key question) and at least 80% correctly answered three of the four key questions. A key question regarding which blood typing test(s) daratumumab interferes with did not achieve satisfactory effectiveness (60% correct responses). In a weighted analysis, 79% of respondents correctly identified the recommended measures for daratumumab-treated patients requiring transfusion. This was attributed to an error in the survey's German translation; in a sensitivity analysis, 90% of participants correctly responded to this question.Conclusions: Results suggest that participants were aware of the educational materials, the risk of daratumumab interference with blood testing, and recommended measures to mitigate that risk. [ABSTRACT FROM AUTHOR]

Background: Although antibody screening is mandatory according to the National Blood Policy of India, the prevalence of irregular red cell antibody and its specificities are not much reported in South Indian population. Aims and Objectives: The objective of this study is to find the prevalence of irregular red cell antibodies and positive direct antiglobulin test (DAT) in healthy blood donors in South India population. Materials and Methods: This is a retrospective observational study conducted in the department of transfusion medicine from April 2011 to March 2018 (7 years) at a tertiary care referral center, Chennai, Tamil Nadu. Red cell antibody screening of all voluntary blood donors was performed using commercial O cells (ID DiaCell Pool, DiaMed, Cressier sur Morat, Switzerland). Positive sera were further investigated to identify the irregular erythrocyte antibody by commercially available red cell panel (ID-DiaPanel, Diamed-ID Microtyping System). Results: A total of 40,629 donors were screened for the presence of irregular erythrocyte antibodies. A total of 57 (0.14%) donors showed the presence of irregular antibodies, in which 41 (71.9%) were alloantibodies. Most frequent alloantibodies identified were of MNS blood group system with anti-M being the highest (n = 15, 36.58%), followed by Rh blood group system. Sixteen (0.039%) donors were DAT positive, which were detected during routine crossmatching. Conclusion: Implementation of red cell antibody screening in all the blood donors routinely helped us understand the prevalence of antibodies in our region and its importance in providing compatible blood products and to avoid transfusion reactions.

In human lupus nephritis, tubulointerstitial inflammation (TII) is associated with in situ expansion of B cells expressing anti-vimentin antibodies (AVAs). The mechanism by which AVAs are selected is unclear. Herein, we demonstrate that AVA somatic hypermutation (SHM) and selection increase affinity for vimentin. Indeed, germline reversion of several antibodies demonstrated that higher affinity AVAs can be selected from both low affinity B cell germline clones and even those that are strongly reactive with other autoantigens. While we demonstrated affinity maturation, enzyme-linked immunosorbent assays (ELISAs) suggested that affinity maturation might be a consequence of increasing polyreactivity or even non-specific binding. Therefore, it was unclear if there was also selection for increased specificity. Subsequent multi-color confocal microscopy studies indicated that while TII AVAs often appeared polyreactive by ELISA, they bound selectively to vimentin fibrils in whole cells or inflamed renal tissue. Using a novel machine learning pipeline (CytoSkaler) to quantify the cellular distribution of antibody staining, we demonstrated that TII AVAs were selected for both enhanced binding and specificity in situ. Furthermore, reversion of single predicted amino acids in antibody variable regions indicated that we could use CytoSkaler to capture both negative and positive selection events. More broadly, our data suggest a new approach to assess and define antibody polyreactivity based on quantifying the distribution of binding to native and contextually relevant antigens. [ABSTRACT FROM AUTHOR]

Summary: Monoclonal antibodies are a main player in modern drug discovery. Many antibody screening formats exist, each with specific advantages and limitations. Nonetheless, it remains challenging to screen antibodies for the binding of cell-surface receptors (the most important class of all drug targets) or for the binding to target cells rather than purified proteins. Here, we present a high-throughput droplet microfluidics approach employing dual-color normalized fluorescence readout to detect antibody binding. This enables us to obtain quantitative data on target cell recognition, using as little as 33 fg of IgG per assay. Starting with an excess of hybridoma cells releasing unspecific antibodies, individual clones secreting specific binders (of target cells co-encapsulated into droplets) could be enriched 220-fold after sorting 80,000 clones in a single experiment. This opens the way for therapeutic antibody discovery, especially since the single-cell approach is in principle also applicable to primary human plasma cells.

Introduction: With the increased utilization of immunohematology (IH) analyzers in the transfusion medicine, type, and screen policy is the method of choice. Still, the importance of routine crossmatching could not be overruled. Here, we tried to understand the clinical conditions and safety of red cell transfusion and their outcomes. Materials And Methods: This prospective study was conducted by IH laboratory, Medical College Kolkata, Blood Bank from October 1, 2015 to March 31, 2016. A set of 3cc ethylenediaminetetraacetic acid and clotted blood samples of the patients were received according to sample acceptance criteria. Blood grouping by conventional tube technique followed by crossmatching was performed by column agglutination technology (CAT) in polyspecific (IgG + C3d) gel media. Any positive result was rechecked in duplicate with additional two group-specific donor units. The persistent incompatibility was further evaluated using direct anti-human globulin test, auto control, antibody screening, and antibody identification by CAT. Results: On the evaluation of 14,387 sets of patients' sample, only 100 were found to be incompatible (0.69%). Incompatibility rate is higher in females (59%). Eighty-five of these patients were repeatedly transfused. Only 38% of incompatible crossmatch were positive on indirect anti-human globulin test/antibody screening. Antibody could be identified in 16 of them. Seventeen of 100 incompatible samples (17%) presented with panagglutination, were managed with Rh, Kell phenotype/best-matched red cell units. In these 16 patients, 23 alloantibodies were identified; allo anti-E was the most common. Conclusion: This study showed antibody against the Rh system as the most common cause of incompatibility.

Transfusion support remains the mainstay of supportive treatment for thalassemia patients in spite of recent advances such as stem cell transplantation and gene therapy. Thalassemia intermedia (TI) patients generally do not require regular transfusion support but can develop severe anemia, requiring frequent transfusion during the period of stress such as infection and pregnancy. The genetic disparity of red blood cell antigens between donor and recipient leads to sensitization and resulting development of alloantibodies. Red cell alloimmunization leads to incompatiblity and delays in issue of compatible units. Majority of these alloantibodies were against Rh and Kell blood group. Here we report a case of 28 years old TI who developed anti-c following multiple transfusions since the age of 18 years. The patient was transfused with c antigen-negative, A positive anti-human globulin cross-matched blood unit. Thus, we emphasize to include antibody screening routinely in multi-transfused patients and provision of at least Rh phenotype-matched blood to prevent further alloimmunization.

Background & objectives: Blood transfusion therapy involves multiple steps to ensure selection of safe blood component for transfusion. This includes testing for infectious markers, full ABO compatibility, free from any clinically significant red cell antibodies and acceptable donor's red cell survival rates without destruction of recipient's red cells. The red cell antibodies present in healthy blood donors can cause severe haemolytic transfusion reaction, especially in massive blood transfusion recipients and paediatric patients. Hence, screening of red cell antibodies in donor blood is important to provide compatible blood products and to avoid haemolytic transfusion reactions in susceptible patient population. This study was planned to assess prevalence, aetiology and type of unexpected red cell antibodies in a large number of whole blood donor population in north India. Methods: This three-year prospective observational study included blood donor samples for antibody screening from January 2015 to December 2017. A total of 166,803 healthy blood donors including 156,128 (93.6%) males and 10,675 (6.4%) females were screened. Results: The prevalence of red cell antibodies was 0.17 per cent in our donor population. Of the total 286 donors with red cell antibodies, 248 (86.7%) had alloantibodies, 30 (10.5%) had autoantibodies and eight donors (2.8%) showed positive antibody screening with inconclusive results. Interpretation & conclusions: Alloimmunization to red cell antigens is a challenging task for current transfusion practices. The antibody screening in blood donors may improve the quality and safety of blood transfusion in the recipients. It also reduces the risk of complications from incompatible blood transfusions. [ABSTRACT FROM AUTHOR]

Objectives: Detection of maternal irregular antibodies against red blood cell antigen is vital in the management of hemolytic disease of fetus and newborn. There are no uniform guidelines related to antenatal antibody screening and identification in the developing Country like India. This study was aimed to identify such alloimmunization and its associations. Materials and Methods: This prospective study was conducted on antenatal mothers at a tertiary care center. The mothers having a history of anti-D administration, blood transfusion, and autoimmune disorders were excluded from the study. Initial indirect antiglobulin test (IAT) was performed in all blood samples by conventional tube technique (CTT) to identify alloimmunization. IAT-positive samples were screened for irregular antibody by column agglutination technology (CAT). Antibody screen-positive samples were further analyzed in 11-cell panel by CAT. Antibody strength was measured by serial double dilution by CTT. The source of isoimmunization was identified by extended Rh phenotype of women, husband, and newborn. Results: A total of 12 (2.3%) women out of 530 were positive for IAT and antibody screen. Antibody could be identified in 11 women, of which anti-D (5) was the most common, followed by anti-C + anti-D (4), anti-C + anti-E (1), and anti-C (1). All four cases of anti-D + anti-C were distinguished from anti-G by differential adsorption and elution. There was a significant association with alloimmunization versus increased gravid status, antepartum hemorrhage, and past history of newborns with neonatal jaundice. Conclusion: All pregnant women with history of antepartum haemorrhage, newborn with neonatal jundice should be screened for alloantibody for early detection and better management of HDFN. [ABSTRACT FROM AUTHOR]

Toward the goal of increasing the throughput of high-resolution mass characterization of intact antibodies, we developed a RapidFire-mass spectrometry (MS) assay using electrospray ionization. We achieved unprecedented screening throughput as fast as 15 s/sample, which is an order of magnitude improvement over conventional liquid chromatography (LC)-MS approaches. The screening enabled intact mass determination as accurate as 7 ppm with baseline resolution at the glycoform level for intact antibodies. We utilized this assay to characterize and perform relative quantitation of antibody species from 248 samples of 62 different cell line clones at four time points in 2 h using RapidFire-time-of-flight MS screening. The screening enabled selection of clones with the highest purity of bispecific antibody production and the results significantly correlated with conventional LC-MS results. In addition, analyzing antibodies from a complex plasma sample using affinity-RapidFire-MS was also demonstrated and qualified. In summary, the platform affords high-throughput analyses of antibodies, including bispecific antibodies and potential mispaired side products, in cell culture media, or other complex matrices. [ABSTRACT FROM AUTHOR]