Clinical trial NCT06838780: Host Response to Infection by Direct Analysis of Leukocyte Single Cell-type Gene Expression/transcript Abundance, Direct LS-TA
Official title: Peripheral Blood Single Cell-type Expression Profile of Interferon-stimulated and Other Biomarker Genes for Triage of Febrile Patients
Study type: OBSERVATIONAL
Overall status: ACTIVE_NOT_RECRUITING
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
Lead sponsor: Chinese University of Hong Kong
Sponsor class: OTHER
First posted: 2025-02-21
Enrollment: 192
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Time perspective: RETROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients with Infections were patients admitted to ward for treatment of infection.

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).

Detailed description: DIRECT LS-TA is a ratio-based biomarker (RBB) for blood gene expression analysis which can be performed in commonly available equipments (e.g. qPCR or digital PCR machines). Using the ratio of TA of prior defined numerator gene and denominator gene, this RBB can quantify gene expression of the specified constitutional single cell-type (e.g. monocytes and granulocytes) inside a cell-mixture sample of Whole blood.

DIRECT LS-TA was a method pioneered by the PI \[Tang 2017, https://patents.google.com/patent/US9589099B2/\]. And it has been developed for quantification of early B cell response after vaccination \[DOI: 10.3390/genes12070971\].

Recently, the method is used to develop host response biomarkers after infection to differentiate the type of pathogens (such as viral, bacterial or active tuberculosis). Numerator and denominator genes have been identified by using public gene expression datasets for monocytes and granulocytes. Diagnostic performance was good using these public data.

Therefore, these RBBs will be applied in these retrospective samples to evaluate and compare their diagnostic (triage) performance of febrile patients into different pathogen etiologies.

Eligibility criteria: Inclusion Criteria:

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

Exclusion Criteria:

* 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)

Primary outcomes:
measure: Viral host response Direct LS-TA in monocytes (Type I interferon response)
timeFrame: 1 day (first collected sample after admission)
measure: Viral host response Direct LS-TA in granulocytes (Type I interferon response)
timeFrame: 1 day (first collected sample after admission)
measure: Bacterial infection host response Direct LS-TA in monocytes (pro-inflammatory response)
timeFrame: 1 day (first collected sample after admission)
measure: Bacterial infection host response Direct LS-TA in granulocytes (pro-inflammatory response)
timeFrame: 1 day (first collected sample after admission)
measure: Active TB host response Direct LS-TA in monocytes (Type II interferon response)
timeFrame: 1 day (first collected sample after admission)
measure: Active TB host response Direct LS-TA in granulocytes (Type II interferon response)
timeFrame: 1 day (first collected sample after admission)
Secondary outcomes:
measure: Reference intervals and median of these DIRECT LS-TA RBB in the control group
timeFrame: 1 day (first collected sample after admission)
Other outcomes:
Locations:
city: Hong Kong
country: Hong Kong
facility: Dept of Chemical Pathology, Chinese University of Hong Kong
Study officials:
References:
citation: Direct single cell-type gene expression analysis in Whole blood: Novel ratio-based gene expression biomarkers using 2 novel monocyte reference genes (PSAP and CTSS) for monitoring bacterial infection Nelson LS Tang, Tsz-Ki Kwan, Dan Huang, Suk Ling Ma, K.S. Leung bioRxiv 2025.01.27.634977; doi: https://doi.org/10.1101/2025.01.27.634977
citation: 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.
citation: 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.