Mycobacterium Avium Clinical Trial
Official title:
The Pathogenic Role and Diagnostic Implication of Program Cell Death Receptor 1 Expressed on T Cells in Mycobacterium Avium Complex Lung Disease
1. To understand the components of PBMC in MAC-LD patients, including T cells, B cells,
nature killer cells, and monocyte.
2. To confirm the phenomenon of reduced PBMC response in MAC-LD patients
3. To study the proportion of apoptosis and PD-1 expression in T cells among MAC-LD
patients, MAC colonizers, patients with tuberculosis, and healthy controls.
4. To study the apoptosis and PD-1/PD-L1 expression in T cells/macrophage from bronchial
lavage among MAC-LD patients, MAC colonizers, patients with tuberculosis,
5. To examine the PD-1 gene polymorphism and the correlation with MAC-LD.
Background: Nontuberculous mycobacteria Lung disease (NTM-LD) becomes an important clinical
concern, because its incidence has increased over the last decade. Mycobacterium avium
complex (MAC) is the most common responsible species for NTM-LD in Taiwan. The clinical
relevance of MAC in sputum is, however, only 35~42% because it exists in the environment
ubiquitously. According to the guideline of the American Thoracic Society, the diagnosis of
MAC-LD is based on clinical, radiographic, and mycobacteriology criteria which require two
or more positive sputum cultures for MAC. The major limitation of mycobacterial culture is
the long turn-around-time, usually 2-4 weeks. In addition, both mycobacterial culture and
nucleic acid amplification test cannot discriminate true MAC infection and colonization
because airway colonization of MAC is not uncommon. Therefore, diagnosis of MAC-LD remains a
big challenge in clinical practice, and rapid and accurate diagnostic test should be
developed.
Beyond the contemporary diagnostic criteria, the host immune response in NTM disease has
recently been proposed to help diagnosis. Inflammatory markers may represent host response
and discriminate MAC infection from colonization. But inflammatory markers can be influenced
by infection other than MAC infection. By contrast, lymphocyte response to antigen
stimulation may be more specific in diagnosis. In our preliminary results, in-vitro response
of peripheral blood mononuclear cell (PBMC) is lower in MAC-LD than healthy controls. The
underlying mechanism responsible for the reduced PBMC response in MAC-LD is not fully
understood. In previous studies conducted in tuberculosis patients, interaction between
programmed cell death ligand-1 (PD-L1) from dendritic cells and programmed cell death-1
(PD-1) in T cells leads to apoptosis or anergy of T lymphocyte and thus suppresses cellular
immunity. Therefore, it is possible that similar alteration in immune response also occurs
in patients with MAC-LD and correlates with the PBMC response as well as disease severity.
;
Observational Model: Cohort, Time Perspective: Prospective
| Status | Clinical Trial | Phase | |
|---|---|---|---|
| Recruiting |
NCT06266442 -
M. Avium WGS During Mav-PD Treatment
|