TY - JOUR
T1 - Fecal indole as a biomarker of susceptibility to cryptosporidium infection
AU - Chappell, Cynthia L.
AU - Darkoh, Charles
AU - Shimmin, Lawrence
AU - Farhana, Naveed
AU - Kim, Do Kyun
AU - Okhuysen, Pablo C.
AU - Hixson, James
N1 - Publisher Copyright:
© 2016, American Society for Microbiology.
PY - 2016
Y1 - 2016
N2 - Cryptosporidium causes significant diarrhea worldwide, especially among children and immunocompromised individuals, and no effective drug treatment is currently available for those who need it most. In this report, previous volunteer infectivity studies have been extended to examine the association between fecal indole and indole-producing (IP) gut microbiota on the outcome of a Cryptosporidium infection. Fecal indole concentrations (FICs) of 50 subjects and 19 taxa of common gut microbiota, including six IP taxa (11 subjects) were determined in stool samples collected before and after a challenge with Cryptosporidium oocysts. At the baseline, the mean FIC ( ± the standard deviation) was 1.66 ± 0.80mMin those who became infected after a challenge versus 3.20±1.23mMin those who remained uninfected (P = 0.0001). Only 11.1% of the subjects with a FIC of>2.5mMbecame infected after a challenge versus 65.2% of the subjects with a FIC of < 2.5 mM. In contrast, the FICs of infected subjects at the baseline or during diarrhea were not correlated with infection intensity or disease severity. The relative abundances (percent) of Escherichia coli, Bacillus spp., and Clostridium spp. were greater ≥ 2.5-fold in volunteers with a baseline FIC of 2.5 mM, while those of Bacteroides pyogenes, B. fragilis, and Akkermansia muciniphila were greater in those with a baseline FIC of < 2.5 mM. These data indicate that some IP bacteria, or perhaps indole alone, can influence the ability of Cryptosporidium to establish an infection. Thus, preexisting indole levels in the gut join the oocyst dose and immune status as important factors that determine the outcome of Cryptosporidium exposure.
AB - Cryptosporidium causes significant diarrhea worldwide, especially among children and immunocompromised individuals, and no effective drug treatment is currently available for those who need it most. In this report, previous volunteer infectivity studies have been extended to examine the association between fecal indole and indole-producing (IP) gut microbiota on the outcome of a Cryptosporidium infection. Fecal indole concentrations (FICs) of 50 subjects and 19 taxa of common gut microbiota, including six IP taxa (11 subjects) were determined in stool samples collected before and after a challenge with Cryptosporidium oocysts. At the baseline, the mean FIC ( ± the standard deviation) was 1.66 ± 0.80mMin those who became infected after a challenge versus 3.20±1.23mMin those who remained uninfected (P = 0.0001). Only 11.1% of the subjects with a FIC of>2.5mMbecame infected after a challenge versus 65.2% of the subjects with a FIC of < 2.5 mM. In contrast, the FICs of infected subjects at the baseline or during diarrhea were not correlated with infection intensity or disease severity. The relative abundances (percent) of Escherichia coli, Bacillus spp., and Clostridium spp. were greater ≥ 2.5-fold in volunteers with a baseline FIC of 2.5 mM, while those of Bacteroides pyogenes, B. fragilis, and Akkermansia muciniphila were greater in those with a baseline FIC of < 2.5 mM. These data indicate that some IP bacteria, or perhaps indole alone, can influence the ability of Cryptosporidium to establish an infection. Thus, preexisting indole levels in the gut join the oocyst dose and immune status as important factors that determine the outcome of Cryptosporidium exposure.
UR - http://www.scopus.com/inward/record.url?scp=84979729316&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84979729316&partnerID=8YFLogxK
U2 - 10.1128/IAI.00336-16
DO - 10.1128/IAI.00336-16
M3 - Article
C2 - 27245413
AN - SCOPUS:84979729316
SN - 0019-9567
VL - 84
SP - 2299
EP - 2306
JO - Infection and Immunity
JF - Infection and Immunity
IS - 8
ER -