Host Response to Infection by Direct Analysis of Leukocyte Single Cell-type Gene Expression/transcript Abundance, Direct LS-TA

NCT06838780 | Active Not Recruiting

• 1 other identifier: Direct LS-TA retrospective
• Study Type: observational
• Target: 192
• Locations: 1 country
• Sites: 1

Brief Summary

Febrile illness is a common condition, particularly among young patients and it is crucial to have an early triage of patients according to various aetiologies to enable appropriate treatment. Most diagnostic tests are targeted towards the detection of pathogens while other assays are mostly related to serum proteins. Blood cells transcriptome has been explored to differentiate bacterial and viral infections. Here, we propose to develop a rapid test using the host responses in terms of gene expressions of single-cell populations of peripheral leukocytes (monocytes and granulocytes) to differentiate three major categories of infections that are bacterial, viral, and tuberculosis. The assay is called Direct leukocyte single cell-type transcript abundance (TA) assay (DIRECT LS-TA) as it can directly determine the gene expression of a specified single cell-type (e.g. monocytes and granulocytes) among various leukocyte cell populations directly in a peripheral blood sample. Such results signify the nature of host response and can be used to indicate the type of infection (viral, bacterial or active tuberculosis).

Conditions

Gene Expression; Gene Expression Profiling; Infection; Viral Diseases; Bacterial Infections; Active Tuberculosis

Keywords

host response; transcriptome; Single cell-type gene expression; triage; fever; febrile patients

Outcome Measures

Primary Outcomes (6)

• Viral host response Direct LS-TA in monocytes (Type I interferon response)

  Direct LS-TA is a kind of RBB that can be readily quantified by qPCR or dPCR of a pair of genes, the RBB numerator gene and the RBB denominator gene. The biomarker is the ratio of the 2 genes. Single cell-type: Monocyte. RBB numerator gene: IFI27 or IFI44L. RBB denominator gene: PSAP, CTSS or CPVL. The various RBB (e.g. IFI27/PSAP and IFI44L/PSAP ratios) will be compared in terms of their sensitivity/specificity of diagnostic performance in the vaccination control samples and samples from infection groups. AUC of ROC analysis will be performed where appropriate.

  1 day (first collected sample after admission)

• Viral host response Direct LS-TA in granulocytes (Type I interferon response)

  Direct LS-TA is a kind of RBB that can be readily quantified by qPCR or dPCR of a pair of genes, the RBB numerator gene and the RBB denominator gene. The biomarker is the ratio of the 2 genes. Single cell-type: Granulocyte. RBB numerator gene: RSAD2 or IFIT1. RBB denominator gene: SAT1 or SRGN. The various RBB will be compared in terms of their sensitivity/specificity of diagnostic performance in the vaccination control samples and samples from infection groups. AUC of ROC analysis will be performed where appropriate.

  1 day (first collected sample after admission)

• Bacterial infection host response Direct LS-TA in monocytes (pro-inflammatory response)

  Direct LS-TA is a kind of RBB that can be readily quantified by qPCR or dPCR of a pair of genes, the RBB numerator gene and the RBB denominator gene. The biomarker is the ratio of the 2 genes. Single cell-type: Monocyte. RBB numerator gene: VNN1, or NLRC4. RBB denominator gene: PSAP, CTSS or CPVL. The various RBBs will be compared in terms of their sensitivity/specificity of diagnostic performance in the vaccination control samples and samples from infection groups. AUC of ROC analysis will be performed where appropriate.

  1 day (first collected sample after admission)

• Bacterial infection host response Direct LS-TA in granulocytes (pro-inflammatory response)

  Direct LS-TA is a kind of RBB that can be readily quantified by qPCR or dPCR of a pair of genes, the RBB numerator gene and the RBB denominator gene. The biomarker is the ratio of the 2 genes. Single cell-type: Granulocyte. RBB numerator gene: ALPL, ARG1, or ANXA3. RBB denominator gene: SAT1 or SRGN. The various RBB will be compared in terms of their sensitivity/specificity of diagnostic performance in the vaccination control samples and samples from infection groups. AUC of ROC analysis will be performed where appropriate.

  1 day (first collected sample after admission)

• Active TB host response Direct LS-TA in monocytes (Type II interferon response)

  Direct LS-TA is a kind of RBB that can be readily quantified by qPCR or dPCR of a pair of genes, the RBB numerator gene and the RBB denominator gene. The biomarker is the ratio of the 2 genes. Single cell-type: Monocyte. RBB numerator gene: WARS1, ATF3 or CALHM6. RBB denominator gene: PSAP, CTSS or CPVL. The various RBB will be compared in terms of their sensitivity/specificity of diagnostic performance in the vaccination control samples and samples from infection groups. AUC of ROC analysis will be performed where appropriate.

  1 day (first collected sample after admission)

• Active TB host response Direct LS-TA in granulocytes (Type II interferon response)

  Direct LS-TA is a kind of RBB that can be readily quantified by qPCR or dPCR of a pair of genes, the RBB numerator gene and the RBB denominator gene. The biomarker is the ratio of the 2 genes. Single cell-type: granulocyte. RBB numerator gene: ANKRD22, BATF2, CD274, FCGR1A or ETV7. RBB denominator gene: SAT1 or SRGN. The various RBB will be compared in terms of their sensitivity/specificity of diagnostic performance in the vaccination control samples and samples from infection groups. AUC of ROC analysis will be performed where appropriate.

  1 day (first collected sample after admission)

Secondary Outcomes (1)

• Reference intervals and median of these DIRECT LS-TA RBB in the control group

  1 day (first collected sample after admission)

Study Arms (3)

Vaccination Controls

Up to 200 adult samples collected as the baseline of this study will be used to establish the reference ranges of the ratio-based biomarkers by quantitative PCR or digital PCR.

Other: No intervention

Bacterial infection samples

A retrospective sample of adult patients with positive bacterial blood culture.

Other: No intervention

Tuberculosis samples

A retrospective sample of adult patients who were diagnosed to have active tuberculosis disease.

Other: No intervention

Interventions

No intervention OTHER

No intervention for this retrospective study

Bacterial infection samples; Tuberculosis samples; Vaccination Controls

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients with Infections were patients admitted to ward for treatment of infection.

You may qualify if:

• Bacterial infection sample: positive isolation of organism in blood culture (Bacterial infection sample group)
• Clinical diagnosed active TB (Tuberculosis infection group)

You may not qualify if:

• End stage renal failure
• Pregnancy
• Infections for which long term antibiotic treatment is strongly recommended (including infective endocarditis, osteoarticular infections, cerebral or hepatic or lung abscesses, tuberculosis or nontuberculous mycobacterial infections)

Sponsors & Collaborators

• Chinese University of Hong Kong: lead

Study Sites (1)

Dept of Chemical Pathology, Chinese University of Hong Kong

Hong Kong, Hong Kong

Location

Related Publications (3)

• Tang NLS, Kwan TK, Huang D, Ma SL, Leung KS. Direct single cell-type gene expression analysis in peripheral blood: novel ratio-based gene expression biomarkers using 2 novel monocyte reference genes (PSAP and CTSS) for detection of bacterial infection. Hum Mol Genet. 2025 Aug 21;34(17):1458-1470. doi: 10.1093/hmg/ddaf103.

  PMID: 40581066 BACKGROUND

• Huang D, Liu AYN, Leung KS, Tang NLS. Direct Measurement of B Lymphocyte Gene Expression Biomarkers in Peripheral Blood Transcriptomics Enables Early Prediction of Vaccine Seroconversion. Genes (Basel). 2021 Jun 25;12(7):971. doi: 10.3390/genes12070971.

  PMID: 34202032 BACKGROUND

• Huang B, Huang J, Chiang NH, Chen Z, Lui G, Ling L, Kwan MYW, Wong JSC, Mak PQ, Ling JWH, Lam ICS, Ng RWY, Wang X, Gao R, Hui DS, Ma SL, Chan PKS, Tang NLS. Interferon response and profiling of interferon response genes in peripheral blood of vaccine-naive COVID-19 patients. Front Immunol. 2024 Jan 10;14:1315602. doi: 10.3389/fimmu.2023.1315602. eCollection 2023.

  PMID: 38268924 BACKGROUND

Related Links

• Patent about the model to obtain single cell-type gene expression in peripheral blood
• Patent about the model to obtain single cell-type gene expression in peripheral blood

Biospecimen

Retention: SAMPLES WITH DNA

Blood are collected into EDTA or citrate tubes. An aliquot of whole blood (WB) will be processed for RNA fixation by addition of Trizol solution and stored in -70C before total RNA extraction. Another aliquot of WB are separated into granulocytes and PBMC by the Ficoll gradient method. Granulocytes and a portion of PBMC will be fixed by trizol.

MeSH Terms

Conditions

Infections; Virus Diseases; Bacterial Infections; Latent Tuberculosis; Fever

Condition Hierarchy (Ancestors)

Bacterial Infections and Mycoses; Tuberculosis; Mycobacterium Infections; Actinomycetales Infections; Gram-Positive Bacterial Infections; Latent Infection; Body Temperature Changes; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principle investigator

Study Record Dates

• First Submitted: February 17, 2025
• First Posted: February 21, 2025
• Study Start: January 1, 2018
• Primary Completion: January 1, 2026
• Study Completion: January 1, 2026
• Last Updated: March 3, 2025

Record last verified: 2025-02

Locations

HK (1)