Autosomal recessive Bardet-Biedl syndrome: first-degree relatives have no predisposition to metabolic and renal disorders.

Bardet-Biedl Syndrome (BBS) is an autosomal recessive, multisystem, genetically heterogeneous, ciliopathic condition caused by mutations in multiple genes. Here we sought to determine if inheritance of a single BBS mutation increased the risks of frequent disorders of this syndrome such as obesity, hypertension, and diabetes. Various metabolic and renal diseases in a cohort of 46 patients with BBS, prospectively followed for up to 28 years, were compared to recent assessments of these factors in 96 relatives with a heterozygote mutation (carriers) and 37 relatives without a contributing mutation (non-carriers).

Circulating CD14-CD36+ peripheral blood mononuclear cells constitutively produce interleukin-10.

The impact of immune regulatory imbalance covers surprising physiological breadth. Although dominance of anti-inflammatory cytokines such as IL-10 is associated with reduced immune responsiveness and susceptibility to persistent infection, conditions such as cardiovascular disease and diabetes are linked to chronic inflammation and lower IL-10 levels. An appropriate threshold for immune activation is critical for optimal protection from infection and conversely, from short- and long-term side-effects of immune effector mechanisms.

Factors related to loss of HIV-specific cytotoxic T lymphocyte activity.

Objective: To identify factors associated with loss of in vitro stimulated anti-HIV cytotoxic T lymphocyte (CTL) activity.

Methods: Immunological, virological and other characteristics of individuals who sustained anti-HIV CTL activity for prolonged periods with viral replication suppressed below detectable levels were compared with those that lost anti-HIV CTL activity under the same circumstances. Forty-four individuals, all but one receiving highly active antiretroviral therapy or combination therapy, were followed for 56 months.

Immune reconstitution and viral stimulation are required to restore HIV-specific CD8 T cell responses following advanced infection.

The extent to which highly active antiretroviral therapy (HAART) restores human immunodeficiency virus (HIV)-specific immunity in advanced infection is unknown. Therefore, we studied how effective therapy affected HIV-specific CD8(+) T cell responses in 4 individuals who had progressed to advanced infection. CD8(+) T cell responses were assessed by cytotoxicity and interferon-gamma (IFN-gamma) production.

Lack of CD28 expression on HIV-specific cytotoxic T lymphocytes is associated with disease progression.

During HIV infection, CD8+ T cells lacking the costimulatory molecule CD28 increase in number and proportion. This accumulation is associated with disease activity and possibly with CD8+ T-cell dysfunction. In this study, CD8+CD28+ and CD8+CD28- T cells from 41 HIV-infected individuals at various stages of disease were compared in terms of HIV-specific cytotoxicity, TCR beta V repertoire diversity, and cytokine production.

Fas/FasL-independent activation-induced cell death of T lymphocytes from HIV-infected individuals occurs without DNA fragmentation.

We assessed the effects of activation with phorbol myrystic acetate (PMA) and ionomycin on peripheral blood mononuclear cells (PBMC) from HIV-infected individuals by (51)Cr release, propidium iodide (PI) uptake, electron microscopy, and DNA analysis. Up to 70% (51)Cr release was induced from PBMC of HIV-infected individuals, versus up to 26% (51)Cr release from PBMC of non-HIV-infected volunteers. Flow cytometry identified mostly T cells undergoing activation-induced cell death (AICD).

Human immunodeficiency virus type 1 replication, immune activation, and circulating cytotoxic T cells against uninfected CD4+ T cells.

Cytotoxic T lymphocytes (CTL) that kill uninfected activated CD4+ T cells can be induced in vitro by stimulating CD8+ T cells with activated autologous CD4+ T cells. Similar CTL have been detected in circulating T cells from human immunodeficiency virus type I (HIV)-infected individuals. To define the in vivo correlates of this CTL activity, we studied plasma beta-2 microglobulin and HIV RNA levels, T-lymphocyte subset counts, and expression of CD28 on CD8+ T cells concurrently with circulating CTL activity against uninfected CD4+ T cells in 75 HIV-infected individuals at different stages of disease progression.

Functional and genetic integrity of the CD8 T-cell repertoire in advanced HIV infection.

Background: HIV-specific cytotoxic T lymphocytes (CTL) can restrict HIV replication in acute and chronic infection, but disease progression occurs in parallel with declining CTL activity. An understanding of why CTL fail to control HIV replication might reveal important mechanisms of disease progression and enhance prospects for developing effective CTL-based immunotherapies.

Objectives: To investigate the functional integrity, T-cell repertoire diversity, and HIV reactivity of CD8 T lymphocytes in individuals with advanced HIV infection.

HLA-DP epitope typing using monoclonal antibodies.

We have made a panel of murine anti-DP monoclonal antibodies for serological typing of HLA-DP polymorphisms; they can be used in microcytotoxicity (for 7 epitopes) and binding assays (for 8 epitopes). The antibodies detect polymorphic differences in both alpha and beta chains. As immunogens we sometimes used B-lymphoblastoid lines or purified DP molecules but mostly used mouse fibroblast transfectants expressing DP molecules.