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Isolation of Exosomes from the Plasma of HIV-1 Positive Individuals
Published on: January 5, 2016
Cognition and immune function in HIV-1 infection
F L Wilkie1, R Morgan, M A Fletcher
1Department of Psychiatry, University of Miami School of Medicine, FL 33136.
Insights
Cognitive impairments, including slower processing and memory deficits, are present in individuals with Human Immunodeficiency Virus type 1 (HIV-1) infection. These changes occur early and are not linked to immune suppression levels.
Area of Science:
- Neuroscience
- Immunology
- Virology
Background:
- Human Immunodeficiency Virus type 1 (HIV-1) infection can impact cognitive function.
- Understanding the early cognitive changes and their relationship with immune status is crucial for patient management.
Purpose of the Study:
- To compare cognitive function between HIV-1-seropositive and HIV-1-seronegative homosexual men.
- To investigate if cognitive differences are explained by the degree of immunosuppression (CD4 cell count and IgA levels).
Main Methods:
- A cross-sectional study compared 66 HIV-1-seropositive and 37 HIV-1-seronegative men.
- Participants were assessed on various cognitive tests including memory, processing speed, and attention.
- HIV-1-seropositive individuals were categorized into immune groups based on CD4 cell count and IgA levels.
Main Results:
- HIV-1-seropositive individuals exhibited slower information-processing speeds and reduced verbal and visual memory compared to seronegatives.
- These cognitive differences were not attributable to varying degrees of immunosuppression or clinical status.
Conclusions:
- Cognitive alterations are evident in HIV-1-infected individuals prior to the development of AIDS.
- Cognitive changes appear independent of clinical status and immune markers like CD4 cell count and IgA levels.
Objectives:
To determine (1) whether there were differences in cognition between HIV-1-seropositive and HIV-1-seronegative homosexual men and (2), if so, whether these differences could be explained by the degree of immunosuppression [i.e., CD4 cell count and immunoglobulin A (IgA) levels].
Design:
A cross-sectional design was used to compare 66 HIV-1-seropositives (Centers for Disease Control stages II and III, n = 56; stages IVA and IVC-2, n = 10) and 37 HIV-1-seronegatives. The HIV-1-seropositives were classified into three immune groups based on their CD4 cell count (x 10(6)/l) and serum IgA level (mg/dl): (1) moderate [(n = 35) CD4 greater than 400, IgA less than 300]; (2) mixed [(n = 22) either CD4 greater than 400 and IgA greater than 300 or CD4 less than 400 and IgA less than 300] and (3) poor [(n = 9) CD4 less than 400, IgA greater than 300]. HIV-1-seronegatives formed the 'good' immune group (CD4 greater than 400 and IgA less than 300).
Methods:
The four groups were compared on tests of verbal and visual memory, information-processing speeds, visuospatial skills, language processes, attention, psychomotor reaction time, and mental status. Factors other than HIV-1 sero-status that can influence cognitive performance were tested as covariates.
Results:
HIV-1-seropositives had slower information-processing speeds and decreased verbal and visual memory, compared with HIV-1-seronegatives. These differences in cognition were not due to differential immunosuppression or to clinical status among the HIV-1-seropositives.
Conclusions:
Cognitive alterations occur in HIV-1-infected individuals before AIDS and appear to be independent of clinical status and degree of immunosuppression as measured by CD4 cell count and IgA levels.
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