A new sensitive molecular marker for Aspergillus’ Calmodulin gene detection in biological samples, used as a supplementary diagnosis for invasive Aspergillosis (IA)/ Um novo marcador molecular sensível para a detecção do gene Calmodulin em amostras biológicas do Aspergillus, utilizado como diagnóstico suplementar para a Aspergilose invasiva (IA)

Abstract

Introduction: Aspergillosis is caused by the fungi of Aspergillus genus. After inhalation, Aspergillus’ conidia can invade the tracheal bronchus and lungs, resulting in airway colonization, inflammatory granuloma and invasive aspergillosis (IA), which is most likely to occur in neutropenic and immunosuppressed patients. Presently, IA has been associated with COVID-19 in patients admitted to intensive care units (ICU) for longer periods of time. Objective: The objective of this is to design a new molecular marker for detection of Aspergillus spp. in biological samples, in order to develop a new technique for IA diagnosis which is faster, more efficient and safer. Methodology: The primer was designed in silico using conserved sequences of the Calmodulin gene. After confirming the results in silico, in vitro evaluation was performed using the PCR technique. Results: The designed primer showed high specificity for the Aspergillus species. Conclusion: In this study the standardized PCR reaction with the designed marker proved to be safely utilized as a diagnostic method for IA.  The development of a test to aid in the diagnosis of IA is of great importance, since traditional methods are in turn time consuming and generally confused with other diseases. Early diagnosis contributes to faster treatment initiation and increasing the patient's chance of survival. We can conclude that the standardized PCR with the designed primer can be used safely in the development of a diagnostic test for IA, being of low cost, and accessible to patients treated by the public health system. A Patent application for this molecular marker has been submitted, with the number BR1020190281294