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Vibrio parahaemolyticus Disruption of Epithelial Cell Tight Junctions Occurs Independently of Toxin Production. Tarah Lynch, Scott Livingstone, Enrico Buenaventura, Erika Lutter, Jason Fedwick, Andre G. Buret, David Graham, and Rebekah DeVinney INFECTION AND IMMUNITY, Mar. 2005, p. 1275–1283. - PowerPoint PPT Presentation
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Vibrio parahaemolyticus Disruption of Epithelial Cell Tight JunctionsOccurs Independently of Toxin Production
Tarah Lynch, Scott Livingstone, Enrico Buenaventura, Erika Lutter, Jason Fedwick,Andre G. Buret, David Graham, and Rebekah DeVinney
INFECTION AND IMMUNITY, Mar. 2005, p. 1275–1283
Background
• Vibrio parahaemolyticus
• Toxin production: TDH(thermostable direct hemolysin) & TRH(TDH-related hemolysin)
• Barrier function is maintained by tight junction
• Tight junction comprise of transmembrane proteins (ex: actin 、 occludin 、 ZO-1)
• Cytoskeletal components are anchored to tight junction
Background
• Latex agglutination test
Background
• Lactate dehydrogenase (LDH)
Background
• TER ( transepithelial resistance ) & paracellular permeability
Background
• Southern confirmation
-/+ +/- -/- +/+
PCR Southern confirmation
TLH
TRH
TDH
TDH / TRH
+/++/-
+/-
-/+
-/-
Purified TDH
Uninfected
Uninfected
TDH(-) / TRH(-)
toxigenic
nontoxigenic
-/++/-+/++/-
-/-
V. parahaemolyticus disrupts TER and that this disruption occurs independently of toxin production.
+/+
+/-
-/+
-/-
-/-
-/- -/-
TER ↓ paracellular permeability ↑
V. parahaemolyticus disrupts TER and that this disruption occurs independently of toxin production.
-/-
+/+
-/-
-/-
red/green red/green
V. parahaemolyticus disrupts TER and that this disruption occurs independently of toxin production.
+/+
+/- +/- -/+
-/-
-/--/-
-/-
White : 3 hrBlack : 6 hr
Disruption of epithelial barrier function does not correlate with cytotoxicity
V. parahaemolyticus disrupts TER and that this disruption occurs independently of toxin production.
Discussion
• 破壞上皮的 barrier function 產物 TDH & TRH 不是主要的腳色,可能有其他未知物質
TDH/TRH
TDH
TRH
+
+
+
TDH purify
TER ↓
TER ↓
TER ↓
TER ↓
TER ↓
Discussion
• 高濃度 TDH(> 5 HU/ml) 一樣會造成 TER↓,並增加 LDH release ,所以並不排除 TDH and/or TRH 的毒性,只是作用較晚
• 非 TDH and/or TRH 的毒素,影響上皮的 barrier function 作用較早 (1.5 ~ 3 hr postinfection)
Discussion
• 不同的 toxin genotypes 腸炎弧菌,在上皮的 barrier function 有相同的反應,說明可能是由其他物質造成的
• 當測 LDH release 指出破壞上皮的 barrier function 跟 cytotoxicity 無關, LDH release 測得於 cell lysis ,但不能決定 cell 開始 apoptosis
TDH/TRH
TDH
TRH
+
+
+
TDH purify
TER ↓
TER ↓
TER ↓
TER ↓
TER ↓
V. parahaemolyticus disrupts TER and that this disruption occurs independently of toxin production.
Summary
TER ↓ TDH purify LDH release
Disruption of epithelial barrier function does not correlate with cytotoxicity
Summary