Fast and Accurate Pneumocystis Pneumonia Diagnosis in Human Samples Using a Label-Free Plasmonic Biosensor

Olalla Calvo-Lozano1, Anna Aviñó2, Vicente Friaza3

  • 1Nanobiosensors and Bioanalytical Applications Group (NanoB2A), Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC, CIBER in Bioengineering, Biomaterials and Nanomedicine and BIST, Campus UAB Bellaterra, 08193 Barcelona, Spain.

Insights

A new optical biosensor offers a faster, decentralized method for diagnosing Pneumocystis pneumonia (PCP). This surface plasmon resonance (SPR) technique efficiently detects the fungus in patient samples, improving upon traditional PCR methods.

Area of Science:

  • Biomedical Engineering
  • Infectious Diseases
  • Molecular Diagnostics

Background:

  • Pneumocystis pneumonia (PCP) is a severe opportunistic infection in immunocompromised individuals.
  • Current diagnostic methods like PCR are sensitive but time-consuming and require specialized facilities.
  • Lack of specific symptoms complicates early and accurate PCP diagnosis.

Purpose of the Study:

  • To develop and validate an optical biosensor for rapid, decentralized detection of *Pneumocystis jirovecii*.
  • To utilize surface plasmon resonance (SPR) with specific hairpin probes for efficient fungal detection.
  • To offer an alternative diagnostic approach that overcomes limitations of current methods.

Main Methods:

  • Development of an SPR-based optical biosensor.
  • Design of poly-purine reverse-Hoogsteen hairpin probes for detecting the *P. jirovecii* mitochondrial large subunit ribosomal RNA (mtLSU rRNA) gene.
  • Real-time, label-free detection and analysis of target nucleic acid sequences.
  • Testing with clinical samples including bronchoalveolar lavages and nasopharyngeal aspirates.

Main Results:

  • The biosensor achieved real-time, label-free detection of the *P. jirovecii* mtLSU rRNA gene.
  • Demonstrated excellent selectivity and reproducibility with a limit of detection around 2.11 nM.
  • Successfully identified *P. jirovecii* in preliminary clinical samples from human lung fluids.
  • Preliminary evaluation showed rapid and specific identification in patient samples.

Conclusions:

  • The SPR biosensor provides a sensitive, selective, and rapid diagnostic tool for *Pneumocystis pneumonia*.
  • This technology enables efficient and decentralized diagnostics, overcoming limitations of conventional PCR.
  • The developed biosensor holds potential for fast, direct detection of PCP in clinical settings.