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Assessment of Cocaine-induced Behavioral Sensitization and Conditioned Place Preference in Mice
Published on: February 18, 2016
Human T lymphocyte subpopulation and NK cell alterations in persons exposed to cocaine
1University of Miami School of Medicine, Department of Pathology, Florida 33101.
Insights
Cocaine use alters immune cell populations, reducing CD4+ T cells and increasing Natural Killer (NK) cells. These changes in T cell subsets may impact the immune system's ability to fight infection and cancer.
Area of Science:
- Immunology
- Toxicology
- Flow Cytometry
Background:
- Cocaine use is prevalent and associated with various health issues.
- Understanding the immunological impact of cocaine is crucial for assessing host defense.
- Previous research suggests potential immune dysregulation in substance users.
Purpose of the Study:
- To investigate immunophenotypic changes in peripheral blood mononuclear cells of cocaine-positive individuals.
- To examine the effects of cocaine on T cell subpopulations, Natural Killer (NK) cells, and B cells.
- To correlate immune cell variations with cocaine levels and serum protein concentrations.
Main Methods:
- Flow cytometry was used to analyze peripheral blood mononuclear cells.
- Single- and dual-color immunofluorescence staining was performed.
- Evaluated NK, T, and B cell populations, T cell coexpression of surface molecules, serum proteins, and demographic variables.
Main Results:
- Cocaine-positive patients showed reduced CD4+ T cells and increased NK cells.
- Significant shifts in T cell subpopulations were observed, including increased activated T cells (CD4+, CD8+, IL2r+ CD4 T cells).
- Reduced "memory" CD8+ T cells (CD45RO+) and increased CD45R+/CD8+ T cells were noted; correlations between T cell percentages and cocaine levels were found in some cases.
Conclusions:
- Cocaine use is associated with significant alterations in T cell subpopulations and NK cell numbers.
- These immunophenotypic changes suggest a disruption of immune cell networks.
- The observed immune dysregulation may compromise host resistance to infections and malignancy.
Abstract:
Immunophenotypic changes in peripheral blood mononuclear cells were analyzed by flow cytometry in several patient groups positive for cocaine in their urine. Single- and dual-color immunofluorescence staining was performed to examine total numbers of NK, T, and B cells, as well as the coexpression of surface molecules on T cells associated with memory function, helper/inducer capacity, and activation status. In addition, levels of several serum proteins (including immunoglobulins) and other demographic variables were evaluated. Our results show that cocaine-intoxicated patients display reductions in the total percentage of CD4+ T cells and increases in the number of NK cells. Dramatic shifts within certain T cell subpopulations were also observed. In particular, there appeared to be a preferential stimulation of "activated" T cells as indicated by increased levels of class II+ CD4 and CD8 T cells and IL2r+ CD4 T cells. "Memory" CD8+ T cell subpopulations (i.e., CD45RO+) were reduced in the cocaine-positive patients, whereas CD45R+/CD8+ T cells were accordingly increased in the same individuals. In some cases, direct correlation could be established between certain T cell percentages and cocaine levels. None of the serum protein levels measured appeared to be influenced by cocaine. These findings demonstrate that cocaine utilization is associated with variations in levels of certain T cell subpopulations and other immune cells. This may represent a disruption of particular immunologic cell networks which could ultimately influence host resistance to infection and malignancy.
