Comparison between the Manual Method of Indirect Coombs via Gel Technology and Solid Phase Red Cell Adherence

Evaluation of different methods for antibody titre determination in ABO-incompatible kidney transplantation

Background

Blood type antibody-mediated rejection is considered the main obstacle to ABO blood type-incompatible kidney transplantation. Choosing an appropriate antibody-level determining method and setting a rational baseline are critical for safely conducting ABO-incompatible kidney allografts. However, due to the differences in antibody detection methods between laboratories, there is no unified baseline to confirm the true titer. Therefore, a generally applicable method must be selected to determine the level of anti-ABO antibodies before surgery, and the actual critical titer level should be set accordingly. This study aims to guide the selection of appropriate antibody titer detection methods for ABO-incompatible kidney transplant recipients by comparing the differences in titer results obtained through various detection methods.

Methods

A total of 210 ethylene diamine tetraacetic acid (EDTA)-anticoagulated samples were obtained from patients before or after ABO-I kidney transplantation in our centre. In this study, we tested immunoglobulin M (IgM) and immunoglobulin G (IgG) ABO antibody titres using different detection methods, i.e., a tube test (TT), a microcolumn gel card test (MGT), and a glass bead card test (GBT), to evaluate deviations in antibody levels.

Results

According to our results, the IgM titre presented by the TT varied less than one standard dilution from that of the MGT; while the TT resulted in a 2 to 4 titre deviation from that determined by the GBT. For IgG, the titres obtained by the MGT were always one standard dilution higher than those obtained by the TT, and the TT-based and GBT-based titres differed by 2-3 serial dilution steps.

Conclusions

It is important that clinical laboratories employ a consistent method of sample testing for a particular patient, and indicate the approach used when reporting results. A further clinical retrospective study revealed that the MGT could effectively monitor titre changes following surgery.

Convolutional neural network-based automatic classification for incomplete antibody reaction intensity in solid phase anti-human globulin test image

The precise classification of incomplete antibody reaction intensity (IARI) in hydrogel chromatography medium high density medium solid-phase Coombs test is essential for haemolytic disease screening. However, an automatic and contactless method is required for accurate classification of IARI. Here, we present a deep ensemble learning model that integrates five different convolutional neural networks into a single model for IARI classification. A dataset, including 1628 IARI images and corresponding labels of IARI categories ((-), (1 +), (2 +), (3 +), and (4 +)), was used. We trained our model using 1302 IARIs and validated its performance using 326 IARIs. The proposed model achieved 100%, 99.4%, 99.4%, 100%, and 100% accuracies in the ( −), (1 +), (2 +), (3 +), and (4 +) categories, respectively. The results were compared with those of manual classification by immunologists (average accuracy: 99.8% vs. 88.3%, p < 0.01). Following model assistance, all three immunologists achieved increased accuracy (average accuracy: + 6.1%), with the average accuracy of junior immunologists maximum increasing by 11.3%. The time required for model classification was 0.094 s·image^–1, whereas that required manually was 5.528 s·image^–1. The proposed model can thus substantially improve the accuracy and efficiency of IARI classification and facilitate the automation of haemolytic disease screening equipment.