Effect of Media and Estrogen on Morphological Change in Candida albicans

Introduction: Candida albicans (C. albicans), an opportunistic pathogen, lives symbiotically within the intestine of its human host. Temperature and chemical factors have been shown to induce a morphological change in C. albicans from yeast to filamentous form turning C. albicans pathogenic. In this study, we investigated the intestinal cues that might be responsible for the change. We found that different solid media impact the morphological phenotype so we focused on characterizing these before further testing. We tested Estradiol (E2) because of its known linkage to sepsis and higher levels during infections. Experiments were conducted to compare solid agar plates of YEPD, Minimal Media (MM), and Spider Media (SP) for C. albicans growth to choose the best one for further testing with E2 and other factors that could be prone to causing morphological changes. Methods: C. albicans was inoculated through streak method on different solid media (YEPD, MM, SP) and incubated at 30℃. The effect of 0.1nM E2 on C. albicans morphology was also tested. Morphological changes were assayed through bright-field microscopy. Results: Using the three different medias, we found three distinctive phenotypes: A, B, and C. Out of 6 experiments of 14 MM plates, the expressed phenotype was 86% A and 14% inconclusive of the time. 8 experiments of 17 SP plates showed 100% of phenotype B. 6 experiments of 14 YEPD plates presented phenotype C 92% of the time and 8% inconclusive. For E2 trials, 2 experiments, 6 MM plates showed 50% phenotype A and 50% inconclusive. 4 experiments, 10 SP plates had phenotype B 100%. YEPD 2 experiments, 2 plates had phenotype C at 100%. Conclusion: We have established experimental conditions of media controls for further testing whether E2 and other cues, such as inflammatory cytokines, have inhibitory or positive effects on the growth of C. albicans

Testing Environmental Cues on Candida albicans Morphology

Introduction C. albicans is a commensal fungus which under certain environmental cues (e.g., pH, oxidative stress) shifts morphology from spores to filamentous and becomes invasive within the human body. This work aims to identify the environmental gut cues responsible for this morphological shift. Estrogen (E2) becomes elevated during sepsis, thus the guiding hypothesis states that E2 may represent a factor responsible for the morphological change in C. albicans. Methods A calibration curve of growth of C. albicans in liquid minimal media (MM) was established using a spectrophotometer and correlating optical density with cell counts measured with a hematocyter. Liquid MM was inoculated in quadruplets of three different amounts of C. albicans. To test the effect of estrogen at 1nM concentration, E2 was added at the time of inoculation to one of each tube set, and fetal bovine serum was the positive control in another tube. All tubes were anaerobically grown over 3 nights in a shaking incubator at 30℃. Morphological changes were assayed using bright-field microscopy. Results C. albicans was inoculated in amounts of 1, 2, and 4 million cells into sets of 4 tubes each based on the established growth curve. The MM relationship between OD and number of cells is described by the following equation: 1.06×106 + 1.83×10 7x + 1.68×10 7x 2 , R 2= 0.867. Adding E2 at 1 nM to the liquid media appeared to induce filamentous growth and budding, as with positive control 10% FBS. Conclusion Our preliminary experiments indicate that regardless of initial cell amount, tubes containing E2 seem to induce more filamentous growth in MM, as observed with FBS (positive control). Further experiments to determine effects of E2 at other concentrations would bring more insight, as well as trials combining E2 and FBS to explore if there is an additive or inhibitory effect on filamentation

Effect of Media and Estrogen on Morphological Change in Candida albicans

Introduction: Candida albicans (C. albicans), an opportunistic pathogen, lives symbiotically within the intestine of its human host. Temperature and chemical factors have been shown to induce a morphological change in C. albicans from yeast to filamentous form turning C. albicans pathogenic. In this study, we investigated the intestinal cues that might be responsible for the change. We found that different solid media impact the morphological phenotype so we focused on characterizing these before further testing. We tested Estradiol (E2) because of its known linkage to sepsis and higher levels during infections. Experiments were conducted to compare solid agar plates of YEPD, Minimal Media (MM), and Spider Media (SP) for C. albicans growth to choose the best one for further testing with E2 and other factors that could be prone to causing morphological changes. Methods: C. albicans was inoculated through streak method on different solid media (YEPD, MM, SP) and incubated at 30℃. The effect of 0.1nM E2 on C. albicans morphology was also tested. Morphological changes were assayed through bright-field microscopy. Results: Using the three different medias, we found three distinctive phenotypes: A, B, and C. Out of 6 experiments of 14 MM plates, the expressed phenotype was 86% A and 14% inconclusive of the time. 8 experiments of 17 SP plates showed 100% of phenotype B. 6 experiments of 14 YEPD plates presented phenotype C 92% of the time and 8% inconclusive. For E2 trials, 2 experiments, 6 MM plates showed 50% phenotype A and 50% inconclusive. 4 experiments, 10 SP plates had phenotype B 100%. YEPD 2 experiments, 2 plates had phenotype C at 100%. Conclusion: We have established experimental conditions of media controls for further testing whether E2 and other cues, such as inflammatory cytokines, have inhibitory or positive effects on the growth of C. albicans