Adjunctive Thymosin Beta-4 Treatment Influences MΦ Effector Cell Function to Improve Disease Outcome in Pseudomonas aeruginosa-Induced Keratitis.

Wang Y, Carion TW, Ebrahim AS, Sosne G, Berger EA

International journal of molecular sciences13 Oct 2021Cited by 8 (Europe PMC)

PMID34681676PMCIDPMC8537948DOI10.3390/ijms222011016PepBankPUB-34681676

Summary

Our previous work has shown that topical thymosin beta 4 (Tβ4) as an adjunct to ciprofloxacin treatment reduces inflammatory mediators and inflammatory cell infiltrates (neutrophils/PMN and macrophages/MΦ) while enhancing bacterial killing and wound healing pathway activation in an experimental model of P. aeruginosa-induced keratitis. This study aimed to mechanistically examine how Tβ4 influences MΦ function in particular, leading to reduced inflammation and enhanced host defense following P. aeruginosa-induced infection of the cornea. Flow cytometry was conducted to profile the phenotype of infiltrating MΦ after infection, while generation of reactive nitrogen species and markers of efferocytosis were detected to assess functional activity. In vitro studies were performed utilizing RAW 264.7 cells to verify and extend the in vivo findings. Tβ4 treatment decreases MΦ infiltration and regulates the activation state in response to infected corneas. MΦ functional data demonstrated that the adjunctive Tβ4 treatment group significantly downregulated reactive nitrogen species (RNS) production and efferocytotic activity. In addition, the in vitro studies showed that both Tβ4 alone and adjunctive Tβ4 treatment influenced MΦ cellular function following LPS stimulation. Collectively, these data provide further evidence that adjunctive Tβ4 + ciprofloxacin treatment offers a more efficacious option for treating bacterial keratitis. Not only does the adjunctive therapy address both the infectious pathogen and corneal wound healing response, but it also influences MΦ infiltration, activation, and function, as revealed by the current study.

CC BYText from Europe PMC. Highlighted sentences are the source of results.

Results from this study6

1 result from studies that gave the peptide. No result from this study comes from people.

01LabIn vitro (cells)Mechanism
In RAW 264.7 cells, Tβ4 alone influenced macrophage cellular function following LPS stimulation.
In plain wordsIn cells, Tβ4 alone changed macrophage function after an inflammatory trigger.
Peptide
Thymosin beta-4 (human)
Outcome
Direction not reportedMacrophage function with Tβ4 alone
Study
n: not reported in source
RAW 264.7 cells after LPS stimulation
Outcome group
Immune response · Eye
Studied dose
Dose not stated
Source sentences
Summary
In addition, the in vitro studies showed that both Tβ4 alone
1 context sentence(design, population, supporting numbers)
Summary · context
In vitro studies were performed utilizing RAW 264.7 cells to verify and extend the in vivo findings.
Show in the study text Report a problemFND-3468167605

Studies that did not test the peptide alone5

In this study, Thymosin beta-4 (human) was a lab tool or a carrier, part of a mix, or the subject of a lab method. These results are not evidence about taking Thymosin beta-4 (human).

02AnimalNot a test of Thymosin beta-4 (human) aloneAnimal study (in vivo)Efficacy outcome
In an experimental model of P. aeruginosa keratitis, Tβ4 treatment decreased macrophage infiltration.
In plain wordsIn a corneal infection model, Tβ4 treatment, used with an antibiotic, reduced the number of macrophages entering the cornea.
Peptide
Thymosin beta-4 (human)
Outcome
DecreaseMacrophage infiltration of infected cornea
Study
n: not reported in source
Pseudomonas aeruginosa-induced keratitis
Outcome group
Inflammation markers · Eye
Source sentences
Summary
Tβ4 treatment decreases MΦ infiltration
1 context sentence(design, population, supporting numbers)
Summary · context
Our previous work has shown that topical thymosin beta 4 (Tβ4) as an adjunct to ciprofloxacin treatment reduces inflammatory mediators and inflammatory cell infiltrates (neutrophils/PMN and macrophages/MΦ) while enhancing bacterial killing and wound healing pathway activation in an experimental model of P. aeruginosa-induced keratitis.
In this study, Thymosin beta-4 (human) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking Thymosin beta-4 (human).
Show in the study text Report a problemFND-3468167601
03AnimalNot a test of Thymosin beta-4 (human) aloneAnimal study (in vivo)Mechanism
In an experimental model of P. aeruginosa keratitis, Tβ4 treatment regulated the activation state of macrophages in infected corneas.
In plain wordsIn a corneal infection model, Tβ4 treatment, used with an antibiotic, changed how activated the macrophages were.
Peptide
Thymosin beta-4 (human)
Outcome
Direction not reportedMacrophage activation state
Study
n: not reported in source
Pseudomonas aeruginosa-induced keratitis
Outcome group
Immune response · Eye
Source sentences
Summary
Tβ4 treatment decreases MΦ infiltration and regulates the activation state in response to infected corneas.
1 context sentence(design, population, supporting numbers)
Summary · context
Our previous work has shown that topical thymosin beta 4 (Tβ4) as an adjunct to ciprofloxacin treatment reduces inflammatory mediators and inflammatory cell infiltrates (neutrophils/PMN and macrophages/MΦ) while enhancing bacterial killing and wound healing pathway activation in an experimental model of P. aeruginosa-induced keratitis.
In this study, Thymosin beta-4 (human) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking Thymosin beta-4 (human).
Show in the study text Report a problemFND-3468167602
04AnimalNot a test of Thymosin beta-4 (human) aloneAnimal study (in vivo)Mechanism
In an experimental model of P. aeruginosa keratitis, adjunctive Tβ4 treatment significantly downregulated macrophage reactive nitrogen species production.
In plain wordsIn a corneal infection model, Tβ4 used with an antibiotic lowered macrophage production of reactive nitrogen species.
Peptide
Thymosin beta-4 (human)
Outcome
DecreaseReactive nitrogen species production, adjunctive Tβ4
Study
n: not reported in source
Pseudomonas aeruginosa-induced keratitis
Outcome group
Immune response · Eye
Source sentences
Summary
MΦ functional data demonstrated that the adjunctive Tβ4 treatment group significantly downregulated reactive nitrogen species (RNS) production and efferocytotic activity.
1 context sentence(design, population, supporting numbers)
Summary · context
Our previous work has shown that topical thymosin beta 4 (Tβ4) as an adjunct to ciprofloxacin treatment reduces inflammatory mediators and inflammatory cell infiltrates (neutrophils/PMN and macrophages/MΦ) while enhancing bacterial killing and wound healing pathway activation in an experimental model of P. aeruginosa-induced keratitis.
In this study, Thymosin beta-4 (human) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking Thymosin beta-4 (human).
Show in the study text Report a problemFND-3468167603
05AnimalNot a test of Thymosin beta-4 (human) aloneAnimal study (in vivo)Mechanism
In an experimental model of P. aeruginosa keratitis, adjunctive Tβ4 treatment significantly downregulated macrophage efferocytotic activity.
In plain wordsIn a corneal infection model, Tβ4 used with an antibiotic lowered macrophage efferocytosis, the clearing of dying cells.
Peptide
Thymosin beta-4 (human)
Outcome
DecreaseEfferocytotic activity, adjunctive Tβ4
Study
n: not reported in source
Pseudomonas aeruginosa-induced keratitis
Outcome group
Immune response · Eye
Source sentences
Summary
MΦ functional data demonstrated that the adjunctive Tβ4 treatment group significantly downregulated reactive nitrogen species (RNS) production and efferocytotic activity.
1 context sentence(design, population, supporting numbers)
Summary · context
Our previous work has shown that topical thymosin beta 4 (Tβ4) as an adjunct to ciprofloxacin treatment reduces inflammatory mediators and inflammatory cell infiltrates (neutrophils/PMN and macrophages/MΦ) while enhancing bacterial killing and wound healing pathway activation in an experimental model of P. aeruginosa-induced keratitis.
In this study, Thymosin beta-4 (human) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking Thymosin beta-4 (human).
Show in the study text Report a problemFND-3468167604
06LabNot a test of Thymosin beta-4 (human) aloneIn vitro (cells)Mechanism
In RAW 264.7 cells, adjunctive Tβ4 treatment influenced macrophage cellular function following LPS stimulation.
In plain wordsIn cells, Tβ4 used with an antibiotic changed macrophage function after an inflammatory trigger.
Peptide
Thymosin beta-4 (human)
Outcome
Direction not reportedMacrophage function with adjunctive Tβ4
Study
n: not reported in source
RAW 264.7 cells after LPS stimulation
Outcome group
Immune response · Eye
Source sentences
Summary
In addition, the in vitro studies showed that both Tβ4 alone and adjunctive Tβ4 treatment influenced MΦ cellular function following LPS stimulation.
1 context sentence(design, population, supporting numbers)
Summary · context
In vitro studies were performed utilizing RAW 264.7 cells to verify and extend the in vivo findings.
In this study, Thymosin beta-4 (human) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking Thymosin beta-4 (human).
Show in the study text Report a problemFND-3468167606

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

Version 2Current
13 Oct 2026, 01:52 UTC
Study results updated
Version 1
12 Oct 2026, 18:17 UTC
First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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