Quantification of mycobacterial proteins in extrapulmonary tuberculosis cases by nano-based real-time immuno-PCR

Enhanced detection of Mycobacterium Tuberculosis using nanogold-based silver staining enhancement

BackgroundTuberculosis (TB) is a global health challenge from a single infectious agent, Mycobacterium tuberculosis (MTB), and it demands improved diagnostics and therapies.ObjectiveThis work explored a novel method for detecting MTB by combining nanogold labeling (NGL) technology with silver staining to enhance sensitivity and specificity.MethodsNanogold particles (NGPs) were characterized using ultraviolet absorption spectroscopy (UVAS), and their morphology was observed via transmission electron microscopy (TEM). The silver staining enhancement (SSE) system was optimized for a reaction time of 11 min. Fifty drug-resistant tuberculosis (DRT) patients were randomly assigned to a control (Ctrl) group receiving conventional nursing and an experimental (Exp) group treated with continuous nursing intervention (CNI). Quality of Life Instrument for Tuberculosis Patients (QLI-TB) scores were compared over 6 months.ResultsUnmarked NGPs were evenly distributed, while labeled NGPs maintained complete morphology with a gray halo. The detection limit was established at 0.582, reaching as low as 1 pmol/L. For sputum specimens, detection rates were 38.7% for culture, 41.94% for PCR, and 43.54% for nanogold SSE, with no significant differences (P > 0.05). However, patients in the Exp group exhibited significant improvements in physical, psychological, and social functions, as well as the tuberculosis-specific module (TSM) compared to the Ctrl group (P < 0.05).ConclusionsWe demonstrated an innovative method for detecting MTB, demonstrating promising results through method optimization and analysis.

Recent advances in nanomaterials for the detection of mycobacterium tuberculosis (Review)

The world's leading infectious disease killer tuberculosis (TB) has >10 million new cases and ~1.5 million mortalities yearly. Effective TB control and management depends on accurate and timely diagnosis to improve treatment, curb transmission and reduce the burden on the medical system. Current clinical diagnostic methods for tuberculosis face the shortcomings of limited accuracy and sensitivity, time consumption and high cost of equipment and reagents. Nanomaterials have markedly enhanced the sensitivity, specificity and speed of TB detection in recent years, owing to their distinctive physical and chemical features. They offer several biomolecular binding sites, enabling the simultaneous identification of multiple TB biomarkers. Biosensors utilizing nanomaterials are often compact, user‑friendly and well‑suited for detecting TB on location and in settings with limited resources. The present review aimed to review the advances that have occurred during the last five years in the application of nanomaterials for TB diagnostics, focusing on their detection capabilities, structures, working principles and the significance of key nanomaterials. The current review addressed the limitations and challenges of nanomaterials‑based TB diagnostics, along with potential solutions.

Detection of MPT-64 protein in pleural tuberculosis cases by magnetic bead-gold nanoparticle-PCR amplified immunoassay

AIM

Diagnosis of pleural tuberculosis (TB) is challenging; thus, an efficient method is urgently needed.

METHODS

We developed a magnetic-bead-gold nanoparticle-PCR amplified immunoassay (MB-AuNP-I-PCR, liquid system) to detect the Mycobacterium tuberculosis MPT-64 protein in pleural TB patients. AuNPs functionalized with detection antibodies/oligonucleotides were characterized by UV-vis spectroscopy, Transmission/Scanning electron microscopy, Fourier-transform infrared spectrometer, ELISA, and PCR, whereas MBs conjugated with detection antibodies were validated by magneto-ELISA/UV-vis spectroscopy.

RESULTS

We utilized the MB-AuNP-I-PCR for MPT-64 detection in 99 clinical specimens which displayed 85.2% sensitivity and 97.8% specificity to diagnose pleural TB cases. Markedly, the sensitivity achieved by MB-AuNP-I-PCR was noticeably higher (p < 0.01) than magneto-ELISA and GeneXpert.

CONCLUSION

This is a preliminary report to diagnose pleural TB cases by MB-AuNP-I-PCR with promising results that require further corroboration in a higher number of specimens.

Constructions, Purifications and Applications of DNA-Antibody Conjugates: A Review

A DNA-antibody conjugate is a synthetic molecule that combines the unique functions of both an antibody and DNA. With the increased accessibility of commercialized kits, the procedure for constructing conjugates is simplified and the requirement for chemistry background is reduced. As a result, the difficulty of preparing a DNA-antibody conjugate has been significantly lowered. Therefore, the application of DNA-antibody conjugates has attracted more interest in recent years. The most common application of DNA-antibody conjugates is based on the amplifiable property of DNA through PCR. This includes single-conjugate-based immuno-PCR, paired-conjugates-based proximity ligation assay, and proximity extension assay. These methods achieve highly sensitive or specific detection of target proteins. The conjugated single stranded DNA molecules can also specifically hybridize with another strand containing its complementary sequence. This property can be used to selectively bind fluorophore labeled DNA strands, which plays an important role in tissue imaging and spatial omics. All these factors make DNA-antibody conjugates have a broad range of applications in research, diagnosis, and potentially therapy.

Can immuno-PCR (IPCR) transform bacterial disease diagnostics?

INTRODUCTION

Approximately 15 million deaths occur globally each year due to infectious diseases. Timely diagnosis is crucial in promoting cure and preventing disease transmission. Currently, molecular diagnostics have replaced many conventional diagnostic tools due to their inherent limitations. However, the full potential of Immuno Polymerase Chain Reaction (IPCR) remains largely untapped.

AREAS COVERED

This review focuses on the use of IPCR in the diagnosis of different bacterial diseases, highlighting its advantages over traditional methods.

EXPERT OPINION

Early and accurate diagnosis of infectious diseases is crucial because it enhances treatment effectiveness, reduces morbidity and mortality, helps identify potential causes of sepsis earlier, and reduces the risk of unknowingly spreading the disease to others. IPCR in turn has shown promise for the early diagnosis of bacterial diseases as an alternative to conventional culture-based or serological diagnostic assays leading to delayed diagnosis and treatment. IPCR has the potential to revolutionize the diagnostic field due to its increased sensitivity and specificity. Although efforts are needed to reduce the time of the assay and to reduce background noise, IPCR can be combined with other platforms like lateral flow assay/biosensors/automation to improve its use as a point-of-care assay, especially in resource-limited settings.

Diagnosis of abdominal tuberculosis: Detection of mycobacterial CFP-10 and HspX proteins by gold nanoparticle-PCR amplified immunoassay

Attempts were made to improve the efficacy of PCR amplified immunoassay (I-PCR) for diagnosing abdominal TB cases by utilizing the gold nanoparticle (AuNP)-based I-PCR, where AuNPs were functionalized with detection antibodies/oligonucleotides that exhibited 84.3% sensitivity and 95.1% specificity. This assay would improve the ongoing algorithms used in abdominal TB diagnosis.