Candida glabrata’s recurrent infections: biofilm formation during Amphotericin B treatment

Candida species are responsible for recurrent human infections, mostly in immunocompromised patients, due to their high vulnerability. Candida glabrata has a major role in systemic candidiasis and Amphotericin B (AmB), a hospital environment exclusive polyene, is frequently used to treat this disease. Lately, however, clinical evidences of Candida recurrent infections during these treatments are being described, probably due to biofilms (re)formation during this therapy. Thus, this work aims at inferring if C. glabrata biofilms are still being formed during AmB treatment. For that, C. glabrata biofilms were formed in the presence of AmB and analysed by dry weight. Matrix composition was analysed quantifying carbohydrates and, specifically, -1,3 glucans. Results demonstrated that, although in a lesser extent, C. glabrata is able to develop biofilms in the presence of AmB, with a thick extracellular matrix, with an increase on carbohydrates, especially -1,3 glucans. Therefore, it is confirmed that complex biofilms of C. glabrata can be formed during an AmB treatment. This work was supported by the Programa Operacional, Fatores de competitividade – COMPETE and by national funds through FCT – Fundação para a Ciência e a Tecnologia on the scope of the projects FCT PTDC/SAUMIC/119069/2010, RECI/EBB-EBI/0179/2012, PEst-OE/ EQB/LA0023/2013 and C elia F. Rodrigues’ SFRH/BD/ 93078/2013 PhD grant. The authors thank the Project ‘BioHealth - Biotechnology and Bioengineering approaches to improve health quality’, Ref. NORTE-07-0124-FEDER- 000027, co-funded by the Programa Operacional Regional do Norte (ON.2 – O Novo Norte), QREN, FEDER.