Retinal dystrophy in Bardet-Biedl syndrome and related syndromic ciliopathies.

Primary cilia are almost ubiquitously expressed in eukaryotic cells where they function as sensors relaying information either from the extracellular environment or between two compartments of the same cell, such as in the photoreceptor cell. In ciliopathies, a continuously growing class of genetic disorders related to ciliary defects, the modified primary cilium of the photoreceptor, also known as the connecting cilium, is frequently defective. Ciliary dysfunction involves disturbances in the trafficking and docking of specific proteins involved in its biogenesis or maintenance. The main well-conserved ciliary process, intraflagellar transport (IFT), is a complex process carried out by multimeric ciliary particles and molecular motors of major importance in the photoreceptor cell. It is defective in a growing number of ciliopathies leading to retinal degeneration. Retinitis pigmentosa related to ciliary dysfunction can be an isolated feature or a part of a syndrome such as Bardet-Biedl syndrome (BBS). Research on ciliopathies and BBS has led to the discovery of several major cellular processes carried out by the primary cilium structure and has highlighted their genetic heterogeneity.

In vitro antibody synthesis by peripheral blood mononuclear cells from patients with sickle cell disease.

To study the capacity of peripheral blood mononuclear cells (PBMC) from patients with sickle cell disease to synthesize antibodies in vitro, the levels of IgM, IgG, and IgA were quantitated in supernatants of cultured PBMC from a group of asymptomatic adults with sickle cell disease and from normal controls. The rates of spontaneous synthesis of IgM were similar in nonstimulated cultures of PBMC from patients and controls, whereas the amounts of IgG and IgA produced spontaneously by nonstimulated lymphocytes from the patients were significantly greater than those from controls. Similar levels of IgM, IgG, and IgA were detected in the supernatants of cultures stimulated with pokeweed mitogen from patients and controls. Thus, the capacity of PBMC to respond in vitro to pokeweed mitogen was preserved in the patients. The enhanced spontaneous synthesis of IgG and IgA suggests the presence of chronic polyclonal activation of B cells and/or defective regulation of the production of antibodies.

Levels of tumor necrosis factor alpha/cachectin (TNF alpha) in sera from patients with sickle cell disease.

Serum levels of tumor necrosis factor alpha/cachectin (TNF alpha) were studied in a group of adult patients with sickle cell disease (SCD), which include 31 patients with homozygous SS hemoglobinopathy and 10 patients bearing double heterozygous SC hemoglobinopathy and in their matched normal controls. All patients tested did not show any form of crisis for at least 4 weeks prior to the extraction of the sample. The amount of TNF alpha in serum was quantitated by means of an immunoenzymatic assay with a lower limit of detection of 25 pg/ml. The percentage of sera with detectable levels of TNF alpha was significantly increased in SCD patients as compared with the normal controls. Mean TNF alpha values in individuals with detectable levels of the cytokine were also significantly higher in the whole group of SCD patients and in patients bearing either SS or SC hemoglobinopathies than in the control group. An inverse correlation was observed between the percentages of Hb F and the levels of TNF alpha found in the sera from the patients.

Mitogen induced lymphoproliferative responses and lymphocyte sub-populations in patients with sickle cell disease.

Mitogen induced lymphoproliferative responses and lymphocyte sub-populations were studied in a group of sickle cell disease (SCD) patients with homozygous SS hemoglobinopathy. Even though the response to a sub-optimal dose of Con A (0.5 microgram/ml of culture) was significantly decreased in patients with SCD, the proliferative responses to optimal doses of Con A, to PHA and to PWM were preserved in the patients. Addition of indomethacin to the cultures increased to a more significant degree the response to Con A of lymphocytes from patients than from the normal controls. Study of the mononuclear cell subsets indicated that the relative and absolute numbers of B lymphocytes as well as those of monocytes were significantly increased in the patients' group. The percentage of T3+ lymphocytes was found decreased in SCD. However, a rise in the number of T11+ and T4+ lymphocytes as well as in the helper/suppressor cell ratio was observed in the patients as compared to controls.

Antibodies to dietary antigen in serum from patients with sickle cell anemia.

The levels of antibodies of the IgG, IgA and IgM isotypes reacting against ovoalbumin (OVA), gliadin (GL) and cow's milk proteins (CMP), were determined by ELISA in sera from a group of adult patients with sickle cell anemia (SCA) bearing homozygous Ss hemoglobinopathy and from matched health donors. Only patients with steady-state disease were included in the study. Increased amounts of IgG and IgA reacting with OVA, GL and CMP were observed in the group of patients as compared with the controls. In contrast, the levels of IgM antibodies against each of the three dietary antigens were similar in patients and controls. Increased levels of IgG and IgA antibodies against dietary antigens in SCA may result from enhanced permeability of the gut mucosa to macromolecules of dietary origin as a consequence of microinfarctions, chronic polyclonal B cell activation and/or diminished inhibitory control of antibody synthesis.

Amplified ELISA to detect autoantibodies to N-glycolyl-GM3 ganglioside.

Numerous immunochemical methods are now available for the detection of antibodies to gangliosides. An amplified ELISA method for detection of autoantibodies to NGcGM3 ganglioside in the sera of patients with various type of renal diseases was developed. IgM antibodies were found in 39 out of 53 sera of patients using 30 normal healthy blood donor as a negative control. For human IgG conjugate no reactivity to NGcGM3 was seen in the sera. Positive ELISA results were confirmed by TLC-immunostaining using GM3, NGcGM3, NGcGM2 and Standard bovine gangliosides (GM1, GD1a, GD1b and GT1b). All sera were also assayed for reactivity with GM3 in ELISA to determine the line specificity of these antibodies. Based on these results, a protocol for a sensitive and reproducible amplification ELISA system for serum anti-NGcGM3 antibodies in patients with renal or other diseases is presented. The ELISA method described here in appear to be useful adjunt to measure antiNGcGM3 antibodies in sera of patients with various type of renal or other diseases.