Chemokine Receptors on CD8+ T Cells in Patients With Bipolar Disorder

NCT07785167 | Not Yet Recruiting DMC

• 1 other identifier: 09/2026/CL-PAR
• Study Type: observational
• Target: 172
• Locations: 1 country
• Sites: 1

Brief Summary

This observational study investigates the expression profile of chemokine receptors and adhesion molecules in CD8+ T lymphocytes from individuals with Bipolar Disorder compared with healthy controls. The study focuses on CCR5 and CXCR3, which are involved in CD8+ T-cell migration toward the central nervous system, as well as the adhesion-related molecules PSGL-1, VLA-4, and LFA-1. Participants with Bipolar I or Bipolar II Disorder will be drug-naive or drug-free for at least 6 months and will be compared with healthy controls. Differences in molecular expression will also be explored according to the current mood episode, including depressive and manic/hypomanic phases. Gene expression will be assessed by real-time PCR in purified CD8+ T lymphocytes obtained from peripheral blood samples.

Conditions

Bipolar Affective Disorders

Outcome Measures

Primary Outcomes (2)

• Relative mRNA Expression of CCR5 in CD8+ T Lymphocytes

  Relative CCR5 mRNA expression in purified peripheral blood CD8+ T lymphocytes will be quantified by SYBR-based one-step real-time PCR. Gene expression will be normalized to the reference gene and expressed as relative fold change using the 2\^-ΔΔCt method. CCR5 expression will be compared between participants with Bipolar Disorder and healthy controls.

  At baseline (single study visit)

• Relative mRNA Expression of CXCR3 in CD8+ T Lymphocytes

  Relative CXCR3 mRNA expression in purified peripheral blood CD8+ T lymphocytes will be quantified by SYBR-based one-step real-time PCR. Gene expression will be normalized to the reference gene and expressed as relative fold change using the 2\^-ΔΔCt method. CXCR3 expression will be compared between participants with Bipolar Disorder and healthy controls.

  At baseline (single study visit)

Secondary Outcomes (3)

• Relative mRNA Expression of PSGL-1 in CD8+ T Lymphocytes

  At baseline (single study visit)

• Relative mRNA Expression of VLA-4 in CD8+ T Lymphocytes

  At baseline (single study visit)

• Relative mRNA Expression of LFA-1 in CD8+ T Lymphocytes

  At baseline (single study visit)

Other Outcomes (5)

• CCR5 mRNA Expression According to Current Mood Phase

  At baseline (single study visit)

• CXCR3 mRNA Expression According to Current Mood Phase

  At baseline (single study visit)

• PSGL-1 mRNA Expression According to Current Mood Phase

  At baseline (single study visit)

Study Arms (2)

Bipolar Disorder Group

Participants aged 25-35 years with a diagnosis of Bipolar I or Bipolar II Disorder who are either drug-naive or have been free from psychopharmacological treatment for at least 6 months. Participants will be characterized according to the current mood phase, including depressive and manic/hypomanic episodes.

Other: CD8+ T-Cell Gene Expression Analysis

Healthy Control Group

Healthy volunteers aged 25-35 years without clinical evidence of Bipolar I or Bipolar II Disorder and not receiving psychotropic medications. Eligible controls must have a Hamilton Depression Rating Scale score \<8 and a Mania Rating Scale score \<11.

Other: CD8+ T-Cell Gene Expression Analysis

Interventions

CD8+ T-Cell Gene Expression Analysis OTHER

Peripheral blood mononuclear cells will be isolated from peripheral blood by density-gradient centrifugation, followed by purification of CD8+ T lymphocytes using magnetic cell separation. Total RNA will be extracted from purified CD8+ T cells. Relative mRNA expression of CCR5, CXCR3, PSGL-1, VLA-4, and LFA-1 will be assessed using SYBR-based one-step real-time PCR.

Bipolar Disorder Group; Healthy Control Group

Eligibility Criteria

• Age: 25 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

The study population will include adults aged 25 to 35 years with Bipolar I or Bipolar II Disorder and healthy controls. Participants with Bipolar Disorder will be recruited among patients receiving inpatient, Day-Service, or Day-Hospital care at the Psychiatry Unit of the University Hospital "G. Rodolico-San Marco" in Catania, Italy, as part of routine clinical practice. Eligible patients must be drug-naive or have been free from psychopharmacological treatment for at least 6 months. Healthy controls will be recruited from volunteers from the university/hospital community or the general community and must have no clinical evidence of Bipolar Disorder and no current psychotropic treatment. All participants will provide written informed consent before enrollment.

You may qualify if:

• Participants with Bipolar Disorder:
• Age 25 to 35 years.
• Male or female; female participants must be in the mid-luteal phase of the menstrual cycle.
• Clinical presentation consistent with a diagnosis of Bipolar I Disorder or Bipolar II Disorder.
• First diagnosis of Bipolar Disorder with no previous psychopharmacological treatment (drug-naive), or absence of psychopharmacological treatment for at least 6 months (drug-free).
• Ability and willingness to provide written informed consent.
• Healthy Controls Group:
• Age 25 to 35 years.
• Male or female; female participants must be in the mid-luteal phase of the menstrual cycle.
• No current treatment with psychotropic medications.
• No clinical or symptomatic evidence supporting a diagnosis of Bipolar I Disorder or Bipolar II Disorder.
• Hamilton Depression Rating Scale (HAM-D) score \<8.
• Mania Rating Scale (MRS) score \<11.
• No major stressful life events during the previous 6 months, such as bereavement, traumatic events, or divorce.
• Ability and willingness to provide written informed consent.

You may not qualify if:

• Current treatment with corticosteroids, immunosuppressive agents, antibiotics, or hormone replacement therapy.
• Relevant current medical comorbidities, including autoimmune diseases or other clinically significant internal medicine conditions.
• Relevant psychiatric comorbidities.
• Current psychopharmacological treatment or psychopharmacological treatment discontinued less than 6 months before enrollment.

Sponsors & Collaborators

• University of Catania: lead

Study Sites (1)

Psychiatry Unit, Policlinico "G.Rodolico" Hospital, Via Santa Sofia 78

Catania, Sicily, 95123, Italy

Location

Related Publications (4)

• Magioncalda P, Martino M. A unified model of the pathophysiology of bipolar disorder. Mol Psychiatry. 2022 Jan;27(1):202-211. doi: 10.1038/s41380-021-01091-4. Epub 2021 Apr 15.

  PMID: 33859358 BACKGROUND

• Magioncalda P, Martino M, Tardito S, Sterlini B, Conio B, Marozzi V, Adavastro G, Capobianco L, Russo D, Parodi A, Kalli F, Nasi G, Altosole T, Piaggio N, Northoff G, Fenoglio D, Inglese M, Filaci G, Amore M. White matter microstructure alterations correlate with terminally differentiated CD8+ effector T cell depletion in the peripheral blood in mania: Combined DTI and immunological investigation in the different phases of bipolar disorder. Brain Behav Immun. 2018 Oct;73:192-204. doi: 10.1016/j.bbi.2018.04.017. Epub 2018 May 1.

  PMID: 29723656 BACKGROUND

• Barbosa IG, Rocha NP, Assis F, Vieira EL, Soares JC, Bauer ME, Teixeira AL. Monocyte and lymphocyte activation in bipolar disorder: a new piece in the puzzle of immune dysfunction in mood disorders. Int J Neuropsychopharmacol. 2014 Oct 31;18(1):pyu021. doi: 10.1093/ijnp/pyu021.

  PMID: 25539506 BACKGROUND

• Harrison PJ, Geddes JR, Tunbridge EM. The Emerging Neurobiology of Bipolar Disorder. Trends Neurosci. 2018 Jan;41(1):18-30. doi: 10.1016/j.tins.2017.10.006. Epub 2017 Nov 20.

  PMID: 29169634 BACKGROUND

Central Study Contacts

Professor Maria Salvina Signorelli, PhD, MD

CONTACT

+39 095 3782791; maria.signorelli@unict.it

Professor Carmen Concerto, PhD, MD

CONTACT

carmen.concerto@unict.it

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Clinical Professor

Study Record Dates

• First Submitted: August 20, 2026
• First Posted: August 25, 2026
• Study Start (Estimated): September 7, 2026
• Primary Completion (Estimated): September 7, 2028
• Study Completion (Estimated): September 7, 2028
• Last Updated: August 25, 2026

Record last verified: 2026-08

Data Sharing

• IPD Sharing: Will not share

Locations

IT (1)