Non-Invasive Immunofluorescence Assessment of Lycopene Supplementation Status in Skin Smears.

Circulating lycopene level is negatively associated with the prevalence of cardiovascular disease, cancers (prostate and breast), type 2 diabetes mellitus, and aging. Traditionally, lycopene is measured in biological specimens by a combination of high-performance liquid chromatography (HPLC) and mass spectrometry methods. Moreover, as we recently reported, tissue/cell lycopene depositions can be observed by the immunohistochemistry method with a newly developed monoclonal antibody (mAb) against lycopene. A main objective of this study is to evaluate the performance of a new noninvasive immunofluorescence (IF) lycopene quantification skin test with mAbs against lycopene versus HPLC lycopene assay of serum lycopene in volunteers subjected to lycopene supplementation which represents a novel approach to lycopene measurement methodology. For this purpose, 32 healthy volunteers, 30-40 years old, were supplemented with lycopene (n = 15) or placebo (n = 17) for a period of 4 weeks. It was found that lycopene supplementation leads to a significant increase in serum lycopene concentration after 2 and 4 weeks by 2.6- and 3.4-fold over control, respectively. This was accompanied by a concordant step-wise rise in IF staining of skin corneocytes and sebum, quantifiable by arbitrary IF scores. Placebo supplementation did not affect serum lycopene values or intensity of IF staining of the skin samples. There was 86.6% agreement in paired HPLC/IF variants for the intermediate time point and 80.0% agreement at the end of the study in the lycopene group. Intraclass correlation between paired values in this group was +0.49 for the 2-week time point and +0.63 for the end point. These results indicate that the new antibody-based skin assay can be used for rapid detection of lycopene deficiencies. Moreover, the noninvasive nature of the skin swab test would allow using it to monitor, optimize, and personalize lycopene supplementation protocol of risk groups in the general population.

Identification of chlamydial T3SS inhibitors through virtual screening against T3SS ATPase.

Chlamydia trachomatis is a widespread sexually transmitted pathogen that resides within a special vacuole inside host cells. Although acute infection can be treated with antibiotics, chlamydia can enter persistent state, leading to chronic infection that is difficult to cure. Thus, novel anti-chlamydial compounds active against persistent chlamydia are required. Chlamydiae rely upon type III secretion system (T3SS) to inject effector proteins into host cell cytoplasm, and T3SS inhibitors are viewed as promising compounds for treatment of chlamydial infections. C. trachomatis ATPase SctN is an important T3SS component and has not been targeted before. We thus used virtual screening against homology modeled SctN structure to search for SctN inhibitors. Selected compounds were tested for their ability to inhibit chlamydial survival and development within eukaryotic cells, and for the ability to suppress normal T3SS functioning. We identified two compounds that were able to block normal protein translocation through T3SS and inhibit chlamydial survival within eukaryotic cells in 50-100 µm concentrations. These two novel T3SS inhibitors also possessed relatively low toxicity toward eukaryotic cells. A small series of derivatives was further synthesized for the most active of two inhibitors to probe SAR properties.

Generation and Application of Monoclonal Antibody Against Lycopene.

A monoclonal antibody (Mab) against lycopene was developed from hybridoma clones obtained from BALB/c mice immunized with trans-isomer of lycopene (t-lycopene, t-LC) conjugated with colloidal gold particles. An alternating immunization schedule which included injection of both formulations of immunogen (without and with Freund's adjuvant) was most effective in the elucidation of a measurable immune response to the t-Lycopene conjugate. Selected hybridoma clones were able to produce an Mab positive in competition assay. In particular, preincubation of 6B9 Mabs with t-LC abolished the ability of 6B9 Mabs to bind LC in the competition assay. Mabs produced by other clones (4F10, 4A3, and 3B12) worked similarly. Analysis of antigen specificity showed that 6B9 Mab raised against t-LC did not recognize other carotenoids such as lutein and carotene. Mab 6B9 was shown to recognize lycopene on a glass surface and in the settings of indirect immunofluorescence experiments performed in cultured hepatocytes and alveolar macrophages incubated with and without lycopene, as well as in sebum and corneocyte specimens from the skin of volunteers supplemented with nutraceutical formulation of lycopene. Newly generated Mabs against lycopene may provide a valuable tool for different analytical assays of lycopene content in various biological, agricultural, and food products.