MALDI-TOF mass spectrometry of saliva samples as a prognostic tool for COVID-19

J Oral Microbiol. 2022 Feb 27;14(1):2043651. doi: 10.1080/20002297.2022.2043651. eCollection 2022.

Abstract

Background: The SARS-CoV-2 infections are still imposing a great public health challenge despite the recent developments in vaccines and therapy. Searching for diagnostic and prognostic methods that are fast, low-cost and accurate are essential for disease control and patient recovery. The MALDI-TOF mass spectrometry technique is rapid, low cost and accurate when compared to other MS methods, thus its use is already reported in the literature for various applications, including microorganism identification, diagnosis and prognosis of diseases.

Methods: Here we developed a prognostic method for COVID-19 using the proteomic profile of saliva samples submitted to MALDI-TOF and machine learning algorithms to train models for COVID-19 severity assessment.

Results: We achieved an accuracy of 88.5%, specificity of 85% and sensitivity of 91.5% for classification between mild/moderate and severe conditions. When we tested the model performance in an independent dataset, we achieved an accuracy, sensitivity and specificity of 67.18, 52.17 and 75.60% respectively.

Conclusion: Saliva is already reported to have high inter-sample variation; however, our results demonstrates that this approach has the potential to be a prognostic method for COVID-19. Additionally, the technology used is already available in several clinics, facilitating the implementation of the method. Further investigation using a larger dataset is necessary to consolidate the technique.

Keywords: SARS-CoV-2; Saliva; biomarkers; prognosis; proteomics.

Grants and funding

This work was supported by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP), GP (2018/18257-1, 2018/15549-1, 2020/04923-0), CW (2015/26722-8, 2017/03966-4), CRFM (2018/20468-0), PHB (2021/07490-0), ELD (2020/06409-1), and by Pró-Reitoria de Pesquisa da Universidade de São Paulo, PHB (2021.1.10424.1.9). GP (307854/2018-3), CW, and CRFM (302917/2019-5) were supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). L Rosa-Fernandes, LC Lazari, RM Zerbinati and VF Santiago were supported by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), financial code 001. M Palmieri was supported by Pró-Reitoria de Pesquisa da Universidade de São Paulo (2021.1.10424.1.9). The funders had no role in the study design.