Antimicrobial Effects of Thymosin Beta-4 and Ciprofloxacin Adjunctive Therapy in Pseudomonas aeruginosa Induced Keratitis.

Carion TW, Ebrahim AS, Alluri S, Ebrahim T, Parker T, Burns J, Sosne G, Berger EA

International journal of molecular sciences18 Sept 2020Cited by 12 (Europe PMC)

PMID32961846PMCIDPMC7555736DOI10.3390/ijms21186840PepBankPUB-32961846

Summary

Prior work has indicated that thymosin beta 4 (Tβ4) administered with ciprofloxacin markedly improves disease outcome for Pseudomonas aeruginosa (PA)-induced keratitis. As a result, the goal of the current study was to elucidate mechanisms by which Tβ4 mitigates the corneal response; specifically, regarding its bactericidal influence and potential synergy with ciprofloxacin. An in vitro approach was carried out using minimum inhibitory concentration (MIC) assays to assess bactericidal activity against PA. In addition, antimicrobial peptide (AMP) production was evaluated at the mRNA levels using human corneal epithelial cells in response to lipopolysaccharide (LPS) challenge. The results of the MIC assays did not show direct bactericidal activity with Tβ4 alone, although ciprofloxacin exhibited significant killing at concentrations far lower than clinically dosed. Tβ4, however, displayed an indirect effect on bacterial killing, as shown by an upregulation of AMPs and related molecules. The cumulative data from this study indicate an indirect bactericidal role of Tβ4, as well as a synergistic relationship with ciprofloxacin. Furthermore, ciprofloxacin alone was found to influence cellular functions that otherwise have yet to be reported. These results highlight a mechanism of intracellular communication for Tβ4 and further strengthen its development as an adjunct therapy with antibiotics for corneal infections.

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

Results from this study3

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

01LabIn vitro (cells)Activity measurement
In MIC assays, Tβ4 alone showed no direct bactericidal activity against Pseudomonas aeruginosa.
In plain wordsIn lab tests, Tβ4 alone did not kill Pseudomonas aeruginosa bacteria directly.
Peptide
Thymosin beta-4 (human)
Outcome
No significant changeDirect bactericidal activity against P. aeruginosa
Study
bacterian: not reported in source
Pseudomonas aeruginosa MIC assay
Outcome group
Infection and antimicrobial activity · Infection
Studied dose
Dose not stated
Source sentences
Summary
The results of the MIC assays did not show direct bactericidal activity with Tβ4 alone
2 context sentences(design, population, supporting numbers)
Summary · context
An in vitro approach was carried out using minimum inhibitory concentration (MIC) assays to assess bactericidal activity against PA.
Summary · context
In addition, antimicrobial peptide (AMP) production was evaluated at the mRNA levels using human corneal epithelial cells in response to lipopolysaccharide (LPS) challenge.
Show in the study text Report a problemFND-3296184601
02LabIn vitro (cells)Mechanism
In human corneal epithelial cells challenged with LPS, Tβ4 upregulated antimicrobial peptides and related molecules.
In plain wordsIn cells, Tβ4 raised the gene activity of the cornea's own germ-fighting peptides.
Peptide
Thymosin beta-4 (human)
Outcome
IncreaseAntimicrobial peptide mRNA expression
Study
humann: not reported in source
Human corneal epithelial cells with LPS challenge
Outcome group
Infection and antimicrobial activity · Infection
Studied dose
Dose not stated
Source sentences
Summary
Tβ4, however, displayed an indirect effect on bacterial killing, as shown by an upregulation of AMPs and related molecules.
2 context sentences(design, population, supporting numbers)
Summary · context
An in vitro approach was carried out using minimum inhibitory concentration (MIC) assays to assess bactericidal activity against PA.
Summary · context
In addition, antimicrobial peptide (AMP) production was evaluated at the mRNA levels using human corneal epithelial cells in response to lipopolysaccharide (LPS) challenge.
Show in the study text Report a problemFND-3296184602

Studies that did not test the peptide alone1

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).

03LabNot a test of Thymosin beta-4 (human) aloneIn vitro (cells)Activity measurement
The authors report a synergistic relationship between Tβ4 and ciprofloxacin in the in vitro keratitis study.
In plain wordsIn lab tests, the authors report that Tβ4 and ciprofloxacin worked together against bacteria.
Peptide
Thymosin beta-4 (human)
Outcome
Not applicableSynergy of Tβ4 with ciprofloxacin
Study
bacterian: not reported in source
Pseudomonas aeruginosa with Tβ4 and ciprofloxacin
Outcome group
Infection and antimicrobial activity · Infection
Source sentences
Summary
The cumulative data from this study indicate an indirect bactericidal role of Tβ4, as well as a synergistic relationship with ciprofloxacin.
2 context sentences(design, population, supporting numbers)
Summary · context
An in vitro approach was carried out using minimum inhibitory concentration (MIC) assays to assess bactericidal activity against PA.
Summary · context
In addition, antimicrobial peptide (AMP) production was evaluated at the mRNA levels using human corneal epithelial cells in response to lipopolysaccharide (LPS) challenge.
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-3296184603

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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