Human study PLS-00188

Effect of vitamin A deficiency on thymosin-β4 and CD4 concentrations.

Cross-sectional study · Not reported participants enrolled · not included in the assessments (wrong compound)

Version 1 · published November 8, 2026 · evidence through November 8, 2026 · research snapshot 2026.1.1 · methodology ev-1 · Automated assessment by AI (claude-opus-5-5 and claude-sonnet-5-5), not reviewed by a person.

Only the abstract was available. Essential methods may be missing, which limits what can be judged.

Reports of this study

Every publication, registration and abstract describing this one study. Participants are counted once.

Effect of vitamin A deficiency on thymosin-β4 and CD4 concentrations.primary · Journal, genetic engineering & biotechnology · 2017-10-10 · PMID 30647705 · DOI

Design and participants

Design: Cross-sectional study
Population: Egyptian adults aged 18 to 42 years, both sexes, screened for serum vitamin A. Selected subjects were vitamin A-sufficient or vitamin A-deficient.
Conditions: Vitamin A deficiency
Planned enrollment (registry): Not reported
Enrolled: Not reported
Randomized: Not reported
Completed follow-up: Not reported

Intervention and comparator

What each group received. Related peptides, analogs and combinations are never treated as the compound itself.

What the authors reported

As stated in the sources. This is the authors’ account, not Peptide Library’s assessment.

Adverse events

None reported. That is not evidence of safety, and how safety was monitored isn’t described.

The authors concluded (paraphrased): The authors concluded that vitamin A deficiency may influence serum levels of Tβ4 and CD4. Both were lower in deficient subjects and correlated positively with vitamin A levels.

Peptide Library’s assessment

An automated assessment, made by AI separately from the authors’ conclusions and not reviewed by a person. How risk of bias is assessed.

Limitations

inappropriate endpoint: Tβ4 is measured only as an endogenous serum biomarker. It is not administered, so the study gives no evidence on effects of Tβ4 treatment.
small or imprecise: Only 40 selected subjects were analysed, with just 10 in the vitamin A-sufficient group.
abstract only: Appraisal is based solely on the PubMed abstract, which gives no details on selection criteria or confounders.
no control group: Thymosin β4 was only measured as an endogenous biomarker; no intervention was given, so the study cannot inform treatment effects.

No risk-of-bias assessment has been published for this study’s results.

Claims this study informs

Improves dry eye signs and symptoms: not eligible (not primary study) for “Ocular discomfort and corneal staining”
Is safe for human administration: not eligible (not primary study) for “Adverse events, serious adverse events and discontinuations”

Where each value comes from

author_conclusion: PMID 30647705, abstract (final sentence) · extracted by AI (automated, not verified by a person) · abstract only
design: PMID 30647705, abstract (sentences 4-7) · extracted by AI (automated, not verified by a person) · abstract only
participants: PMID 30647705, abstract (sentences 4-7) · extracted by AI (automated, not verified by a person) · abstract only
population: PMID 30647705, abstract (sentence 4) · extracted by AI (automated, not verified by a person) · abstract only

Version 1 · published November 8, 2026 · evidence through November 8, 2026 · research snapshot 2026.1.1 · methodology ev-1 · Automated assessment by AI (claude-opus-5-5 and claude-sonnet-5-5), not reviewed by a person.

These assessments describe published research. Records marked automated were produced by AI under the published methodology and have not been reviewed by a person; they can contain errors. None of this is medical advice, not a statement about any product’s safety for human use, and not a regulatory approval. Peptide Library’s vendor and partner relationships play no part in them (editorial independence).