Serodiagnosis of Lyme borreliosis with bead based immunoassays using multiplex technology

Borrelia multiplex: a bead-based multiplex assay for the simultaneous detection of Borrelia specific IgG/IgM class antibodies

Background

Lyme borreliosis (LB) is the most common tick-borne infectious disease in the northern hemisphere. The diagnosis of LB is usually made by clinical symptoms and subsequently supported by serology. In Europe, a two-step testing consisting of an enzyme-linked immunosorbent assay (ELISA) and an immunoblot is recommended. However, due to the low sensitivity of the currently available tests, antibody detection is sometimes inaccurate, especially in the early phase of infection, leading to underdiagnoses.

Methods

To improve upon Borrelia diagnostics, we developed a multiplex Borrelia immunoassay (Borrelia multiplex), which utilizes the new INTELLIFLEX platform, enabling the simultaneous dual detection of IgG and IgM antibodies, saving further time and reducing the biosample material requirement. In order to enable correct classification, the Borrelia multiplex contains eight antigens from the five human pathogenic Borrelia species known in Europe. Six antigens are known to mainly induce an IgG response and two antigens are predominant for an IgM response.

Results

To validate the assay, we compared the Borrelia multiplex to a commercial bead-based immunoassay resulting in an overall assay sensitivity of 93.7% (95% CI 84.8–97.5%) and a specificity of 96.5% (95%CI 93.5–98.1%). To confirm the calculated sensitivity and specificity, a comparison with a conventional 2-step diagnostics was performed. With this comparison, we obtained a sensitivity of 95.2% (95% CI 84.2–99.2%) and a specificity of 93.0% (95% CI 90.6–94.7%).

Conclusion

Borrelia multiplex is a highly reproducible cost- and time-effective assay that enables the profiling of antibodies against several individual antigens simultaneously.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07863-9.

Tick-borne zoonoses and commonly used diagnostic methods in human and veterinary medicine

Around the world, human health and animal health are closely linked in terms of the One Health concept by ticks acting as vectors for zoonotic pathogens. Animals do not only maintain tick cycles but can either be clinically affected by the same tick-borne pathogens as humans and/or play a role as reservoirs or sentinel pathogen hosts. However, the relevance of different tick-borne diseases (TBDs) may vary in human vs. veterinary medicine, which is consequently reflected by the availability of human vs. veterinary diagnostic tests. Yet, as TBDs gain importance in both fields and rare zoonotic pathogens, such as Babesia spp., are increasingly identified as causes of human disease, a One Health approach regarding development of new diagnostic tools may lead to synergistic benefits. This review gives an overview on zoonotic protozoan, bacterial and viral tick-borne pathogens worldwide, discusses commonly used diagnostic techniques for TBDs, and compares commercial availability of diagnostic tests for humans vs. domestic animals, using Germany as an example, with the aim of highlighting existing gaps and opportunities for collaboration in a One Health framework.

Modified interpretation criteria significantly improve performance of commercially available confirmatory assays for the serodiagnosis of Lyme borreliosis: a case-control study with clinically defined serum samples

Case-control study for the evaluation of innovative test formats for second-tier testing for the serodiagnosis of Lyme borreliosis (LB). A head-to-head comparison was performed with the test systems ViraStripe, SeraSpot, ViraChip, and recomBead. Serum samples from 62 patients (21 erythema migrans, 33 Lyme neuroborreliosis, 8 late LB) and 91 controls (including 29 potentially cross-reacting sera) were tested. For ViraChip and recomBead, optimised interpretation criteria were developed for both IgG and IgM. The most important modification for the proposed interpretation criteria for ViraChip is the interpretation of strong (> 2.5-fold above cutoff) singular IgG reactions against VlsE as positive. This significantly improves sensitivity (32 to 85%, p < 0.0001) without significant changes in specificity (borderline reactions interpreted as negative). By application of our modified rules, specificity of ViraChip IgM is significantly increased (89 to 97%, p < 0.05; borderline results included to negatives), and sensitivities of recomBead IgG and IgM are also significantly improved (69 to 87%, p < 0.01, and 57 to 74%, p < 0.01, respectively; borderline results included to positives). Further improvement of sensitivity by the rating of strong singular IgG reactions against VlsE as positive can also be shown for recomBead. IgG/IgM result combinations must be interpreted as a function of the assumed disease stage, and the best combinations differ for the various assays. Application of our proposed interpretation criteria significantly improve the discriminatory abilities of two assays; however, this must be confirmed with other data sets. Recommendations from Scientific Societies should be updated as may be necessary.

A multiplex serologic platform for diagnosis of tick-borne diseases

Tick-borne diseases are the most common vector-borne diseases in the United States, with serology being the primary method of diagnosis. We developed the first multiplex, array-based assay for serodiagnosis of tick-borne diseases called the TBD-Serochip. The TBD-Serochip was designed to discriminate antibody responses to 8 major tick-borne pathogens present in the United States, including Anaplasma phagocytophilum, Babesia microti, Borrelia burgdorferi, Borrelia miyamotoi, Ehrlichia chaffeensis, Rickettsia rickettsii, Heartland virus and Powassan virus. Each assay contains approximately 170,000 12-mer linear peptides that tile along the protein sequence of the major antigens from each agent with 11 amino acid overlap. This permits accurate identification of a wide range of specific immunodominant IgG and IgM epitopes that can then be used to enhance diagnostic accuracy and integrate differential diagnosis into a single assay. To test the performance of the TBD-Serochip, we examined sera from patients with confirmed Lyme disease, babesiosis, anaplasmosis, and Powassan virus disease. We identified a wide range of specific discriminatory epitopes that facilitated accurate diagnosis of each disease. We also identified previously undiagnosed infections. Our results indicate that the TBD-Serochip is a promising tool for a differential diagnosis not available with currently employed serologic assays for TBDs.

Promising alternatives for one-tier testing of Lyme borreliosis

A main focus of human health studies is the early detection of infectious diseases to enable more rapid treatment and prevent disease transmission. Diagnosis of Lyme borreliosis has been always challenging because of the lack of specific, but simple assay formats. Two-tiered testing has been recommended by US Centers for Disease Control and Prevention to provide more specific results for diagnosis of Lyme disease. However, such a technique is time consuming and is not well suited for early stage detection. Therefore, many tests were proposed as alternatives to overcome these drawbacks. Simple assays, which are mainly performed in one-tier manner, could be conducted with better performance than the two-tiered testing. Proposed assays utilize both newly identified antigens and new platforms to improve detection performance. These assays can be classified into those based on employing a single antigen and assays based on using multiple antigens. In addition to assays to this type of assays, immunoassays on borreliosis-related biomarkers are available. We report here the most recent assays developed over the last 10 years, for detection of Lyme borreliosis in body fluids.

Performance of a multiplexed serological microarray for the detection of antibodies against central nervous system pathogens

Central nervous system (CNS) infections have multiple potential causative agents for which simultaneous pathogen screening can provide a useful tool. This study evaluated a multiplexed microarray for the simultaneous detection of antibodies against CNS pathogens. The performance of selected microarray antigens for the detection of IgG antibodies against herpes simplex virus 1 and 2 (HSV-1 and HSV-2), varicella-zoster virus (VZV), adenovirus, Mycoplasma pneumoniae and Borrelia burgdorferi sensu lato, was evaluated using serum sample panels tested with reference assays used in a routine diagnostic laboratory. The microarray sensitivity for HSV-1, HSV-2, VZV, adenovirus and M. pneumonia ranged from 77% to 100%, and the specificity ranged from 74% to 97%. Very variable sensitivities and specificities were found for borrelial antigens of three different VlsE protein IR(6) peptide variants (IR6p1, IR6p2, IR6p4) and three recombinant decorin binding proteins A (DbpA; DbpAIa, DbpA91, DbpAG40). For single antigens, good specificity was shown for antigens of IR6p4 and DbpAIa (96%), while DbpA91, IR6p1 and IR6p2 were moderately specific (88–92%). The analytical sensitivity of the microarray was dependent on the borrelial IgG concentration of the specimen. The overall performance and technical features of the platform showed that the platform supports both recombinant proteins, whole viruses and peptides as antigens. This study showed diagnostic potential for all six CNS pathogens, including Borrelia burgdorferi sensu lato, using glutaraldehyde based microarray, and further highlighted the importance of careful antigen selection and the requirement for the use of multiple borrelial antigens in order to increase specificity without a major lack of sensitivity.

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To find a suitable microarray platform that supports different kinds of antigens

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To evaluate the feasibility of a multiplexed glutaraldehyde based microarray

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To detect simultaneously different viral and bacterial antibodies

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Performance of the platform proved promising