Variation in hemolysin A expression between uropathogenic Escherichia coli isolates determines NLRP3-dependent vs. -independent macrophage cell death and host colonization

Ambika M V Murthy; Matthew J Sullivan; Nguyen Thi Khanh Nhu; Alvin W Lo; Minh-Duy Phan; Kate M Peters; Dave Boucher; Kate Schroder; Scott A Beatson; Glen C Ulett; Mark A Schembri; Matthew J Sweet

doi:10.1096/fj.201802100R

Variation in hemolysin A expression between uropathogenic Escherichia coli isolates determines NLRP3-dependent vs. -independent macrophage cell death and host colonization

Ambika M V Murthy, Matthew J Sullivan, Nguyen Thi Khanh Nhu, Alvin W Lo, Minh-Duy Phan, Kate M Peters, Dave Boucher, Kate Schroder, Scott A Beatson, Glen C Ulett, Mark A Schembri, Matthew J Sweet

Biology

Research output: Contribution to journal › Article › peer-review

Abstract

Uropathogenic Escherichia coli (UPEC) is the major cause of urinary tract infections (UTIs). The multidrug-resistant E. coli sequence type 131 (ST131) clone is a serious threat to human health, yet its effects on immune responses are not well understood. Here we screened a panel of ST131 isolates, finding that only strains expressing the toxin hemolysin A (HlyA) killed primary human macrophages and triggered maturation of the inflammasome-dependent cytokine IL-1β. Using a representative strain, the requirement for the hlyA gene in these responses was confirmed. We also observed considerable heterogeneity in levels of cell death initiated by different HlyA+ve ST131 isolates, and this correlated with secreted HlyA levels. Investigation into the biological significance of this variation revealed that an ST131 strain producing low levels of HlyA initiated cell death that was partly dependent on the nod-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, with this response being associated with a host-protective role in a mouse UTI model. When the same ST131 strain was engineered to overexpress high HlyA levels, macrophage cell death occurred even when NLRP3 function was abrogated, and bladder colonization was significantly increased. Thus, variation in HlyA expression in UPEC affects mechanisms by which macrophages die, as well as host susceptibility vs. resistance to colonization.-Murthy, A. M. V., Sullivan, M. J., Nhu, N. T. K., Lo, A. W., Phan, M.-D., Peters, K. M., Boucher, D., Schroder, K., Beatson, S. A., Ulett, G. C., Schembri, M. A., Sweet, M. J. Variation in hemolysin A expression between uropathogenic Escherichia coli isolates determines NLRP3-dependent vs. -independent macrophage cell death and host colonization.

Original language	English
Pages (from-to)	7437-7450
Number of pages	14
Journal	The FASEB Journal
Volume	33
Issue number	6
DOIs	https://doi.org/10.1096/fj.201802100R
Publication status	E-pub ahead of print - 14 Mar 2019

Access to Document

10.1096/fj.201802100R

https://espace.library.uq.edu.au/view/UQ:1b11600

Cite this

Murthy, A. M. V., Sullivan, M. J., Nhu, N. T. K., Lo, A. W., Phan, M.-D., Peters, K. M., Boucher, D., Schroder, K., Beatson, S. A., Ulett, G. C., Schembri, M. A., & Sweet, M. J. (2019). Variation in hemolysin A expression between uropathogenic Escherichia coli isolates determines NLRP3-dependent vs. -independent macrophage cell death and host colonization. The FASEB Journal, 33(6), 7437-7450. Advance online publication. https://doi.org/10.1096/fj.201802100R

@article{7d6cdfe33c834b6b818ed1f376bfd0d3,

title = "Variation in hemolysin A expression between uropathogenic Escherichia coli isolates determines NLRP3-dependent vs. -independent macrophage cell death and host colonization",

abstract = "Uropathogenic Escherichia coli (UPEC) is the major cause of urinary tract infections (UTIs). The multidrug-resistant E. coli sequence type 131 (ST131) clone is a serious threat to human health, yet its effects on immune responses are not well understood. Here we screened a panel of ST131 isolates, finding that only strains expressing the toxin hemolysin A (HlyA) killed primary human macrophages and triggered maturation of the inflammasome-dependent cytokine IL-1β. Using a representative strain, the requirement for the hlyA gene in these responses was confirmed. We also observed considerable heterogeneity in levels of cell death initiated by different HlyA+ve ST131 isolates, and this correlated with secreted HlyA levels. Investigation into the biological significance of this variation revealed that an ST131 strain producing low levels of HlyA initiated cell death that was partly dependent on the nod-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, with this response being associated with a host-protective role in a mouse UTI model. When the same ST131 strain was engineered to overexpress high HlyA levels, macrophage cell death occurred even when NLRP3 function was abrogated, and bladder colonization was significantly increased. Thus, variation in HlyA expression in UPEC affects mechanisms by which macrophages die, as well as host susceptibility vs. resistance to colonization.-Murthy, A. M. V., Sullivan, M. J., Nhu, N. T. K., Lo, A. W., Phan, M.-D., Peters, K. M., Boucher, D., Schroder, K., Beatson, S. A., Ulett, G. C., Schembri, M. A., Sweet, M. J. Variation in hemolysin A expression between uropathogenic Escherichia coli isolates determines NLRP3-dependent vs. -independent macrophage cell death and host colonization.",

author = "Murthy, {Ambika M V} and Sullivan, {Matthew J} and Nhu, {Nguyen Thi Khanh} and Lo, {Alvin W} and Minh-Duy Phan and Peters, {Kate M} and Dave Boucher and Kate Schroder and Beatson, {Scott A} and Ulett, {Glen C} and Schembri, {Mark A} and Sweet, {Matthew J}",

year = "2019",

month = mar,

day = "14",

doi = "10.1096/fj.201802100R",

language = "English",

volume = "33",

pages = "7437--7450",

journal = "The FASEB Journal",

issn = "0892-6638",

publisher = "FASEB",

number = "6",

}

Murthy, AMV, Sullivan, MJ, Nhu, NTK, Lo, AW, Phan, M-D, Peters, KM, Boucher, D, Schroder, K, Beatson, SA, Ulett, GC, Schembri, MA & Sweet, MJ 2019, 'Variation in hemolysin A expression between uropathogenic Escherichia coli isolates determines NLRP3-dependent vs. -independent macrophage cell death and host colonization', The FASEB Journal, vol. 33, no. 6, pp. 7437-7450. https://doi.org/10.1096/fj.201802100R

Variation in hemolysin A expression between uropathogenic Escherichia coli isolates determines NLRP3-dependent vs. -independent macrophage cell death and host colonization. / Murthy, Ambika M V; Sullivan, Matthew J; Nhu, Nguyen Thi Khanh et al.
In: The FASEB Journal, Vol. 33, No. 6, 14.03.2019, p. 7437-7450.

Research output: Contribution to journal › Article › peer-review

TY - JOUR

T1 - Variation in hemolysin A expression between uropathogenic Escherichia coli isolates determines NLRP3-dependent vs. -independent macrophage cell death and host colonization

AU - Murthy, Ambika M V

AU - Sullivan, Matthew J

AU - Nhu, Nguyen Thi Khanh

AU - Lo, Alvin W

AU - Phan, Minh-Duy

AU - Peters, Kate M

AU - Boucher, Dave

AU - Schroder, Kate

AU - Beatson, Scott A

AU - Ulett, Glen C

AU - Schembri, Mark A

AU - Sweet, Matthew J

PY - 2019/3/14

Y1 - 2019/3/14

N2 - Uropathogenic Escherichia coli (UPEC) is the major cause of urinary tract infections (UTIs). The multidrug-resistant E. coli sequence type 131 (ST131) clone is a serious threat to human health, yet its effects on immune responses are not well understood. Here we screened a panel of ST131 isolates, finding that only strains expressing the toxin hemolysin A (HlyA) killed primary human macrophages and triggered maturation of the inflammasome-dependent cytokine IL-1β. Using a representative strain, the requirement for the hlyA gene in these responses was confirmed. We also observed considerable heterogeneity in levels of cell death initiated by different HlyA+ve ST131 isolates, and this correlated with secreted HlyA levels. Investigation into the biological significance of this variation revealed that an ST131 strain producing low levels of HlyA initiated cell death that was partly dependent on the nod-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, with this response being associated with a host-protective role in a mouse UTI model. When the same ST131 strain was engineered to overexpress high HlyA levels, macrophage cell death occurred even when NLRP3 function was abrogated, and bladder colonization was significantly increased. Thus, variation in HlyA expression in UPEC affects mechanisms by which macrophages die, as well as host susceptibility vs. resistance to colonization.-Murthy, A. M. V., Sullivan, M. J., Nhu, N. T. K., Lo, A. W., Phan, M.-D., Peters, K. M., Boucher, D., Schroder, K., Beatson, S. A., Ulett, G. C., Schembri, M. A., Sweet, M. J. Variation in hemolysin A expression between uropathogenic Escherichia coli isolates determines NLRP3-dependent vs. -independent macrophage cell death and host colonization.

AB - Uropathogenic Escherichia coli (UPEC) is the major cause of urinary tract infections (UTIs). The multidrug-resistant E. coli sequence type 131 (ST131) clone is a serious threat to human health, yet its effects on immune responses are not well understood. Here we screened a panel of ST131 isolates, finding that only strains expressing the toxin hemolysin A (HlyA) killed primary human macrophages and triggered maturation of the inflammasome-dependent cytokine IL-1β. Using a representative strain, the requirement for the hlyA gene in these responses was confirmed. We also observed considerable heterogeneity in levels of cell death initiated by different HlyA+ve ST131 isolates, and this correlated with secreted HlyA levels. Investigation into the biological significance of this variation revealed that an ST131 strain producing low levels of HlyA initiated cell death that was partly dependent on the nod-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, with this response being associated with a host-protective role in a mouse UTI model. When the same ST131 strain was engineered to overexpress high HlyA levels, macrophage cell death occurred even when NLRP3 function was abrogated, and bladder colonization was significantly increased. Thus, variation in HlyA expression in UPEC affects mechanisms by which macrophages die, as well as host susceptibility vs. resistance to colonization.-Murthy, A. M. V., Sullivan, M. J., Nhu, N. T. K., Lo, A. W., Phan, M.-D., Peters, K. M., Boucher, D., Schroder, K., Beatson, S. A., Ulett, G. C., Schembri, M. A., Sweet, M. J. Variation in hemolysin A expression between uropathogenic Escherichia coli isolates determines NLRP3-dependent vs. -independent macrophage cell death and host colonization.

U2 - 10.1096/fj.201802100R

DO - 10.1096/fj.201802100R

M3 - Article

C2 - 30869997

SN - 0892-6638

VL - 33

SP - 7437

EP - 7450

JO - The FASEB Journal

JF - The FASEB Journal

IS - 6

ER -