Targeted photodynamic therapy of established soft-tissue infections in mice.

The worldwide rise in antibiotic resistance necessitates the development of novel antimicrobial strategies. Although many workers have used photodynamic therapy (PDT) to kill bacteria in vitro, the use of this approach has seldom been reported in vivo in animal models of infection. We have previously described the first use of PDT to treat excisional wound infections by Gram-(-) bacteria in living mice. However, these infected wound models involved a short timespan between infection (30 min) and treatment by PDT. We now report on the use of PDT to treat an established soft-tissue infection in mice. We used Staphylococcus aureus stably transformed with a Photorhabdus luminescenslux operon (luxABCDE) that was genetically modified to be functional in Gram-(+) bacteria. These engineered bacteria emitted bioluminescence, allowing the progress of the infection to be monitored in both space and time with a low light imaging charge-coupled device (CCD) camera. One million cells were injected into one or both thigh muscles of mice that had previously been rendered neutropenic by cyclophosphamide administration. Twenty-four hours later, the bacteria had multiplied more than one hundredfold; poly-L-lysine chlorin e6 conjugate or free chlorin e6 was injected into one area of infected muscle and imaged with the CCD camera. Thirty minutes later, red light from a diode laser was delivered as a surface spot or by interstitial fiber into the infection. There was a light dose dependent loss of bioluminescence (to <5% of that seen in control infections) not seen in untreated infections or those treated with light alone, but in some cases, the infection recurred. Treatment with conjugate alone led to a lesser reduction in bioluminescence. Infections treated with free chlorin e6 responded less well and the infection subsequently increased over the succeeding days, probably due to PDT-mediated tissue damage. PDT-treated infected legs healed better than legs with untreated infections. This data shows that PDT may have applications in drug-resistant soft-tissue infections.     

Severe teratozoospermia and its influence on pronuclear morphology,embryonic cleavage and compaction

Background  

Fertilization, cell division and embryo development depend on genomic contributions from male and female gametes. We hypothesize that teratozoospermic sperm influences early embryo development and embryo compaction.     

Syndecan-1 and syndecan-4 are involved in RANTES/CCL5-induced migration and invasion of human hepatoma cells

Background

We previously demonstrated that the CC-chemokine Regulated upon Activation, Normal T cell Expressed and Secreted (RANTES)/CCL5 exerts pro-tumoral effects on human hepatoma Huh7 cells through its G protein-coupled receptor, CCR1. Glycosaminoglycans play major roles in these biological events.

Methods

In the present study, we explored 1/ the signalling pathways underlying RANTES/CCL5-mediated hepatoma cell migration or invasion by the use of specific pharmacological inhibitors, 2/ the role of RANTES/CCL5 oligomerization in these effects by using a dimeric RANTES/CCL5, 3/ the possible involvement of two membrane heparan sulfate proteoglycans, syndecan-1 (SDC-1) and syndecan-4 (SDC-4) in RANTES/CCL5-induced cell chemotaxis and spreading by pre-incubating cells with specific antibodies or by reducing SDC-1 or -4 expression by RNA interference.

Results and conclusion

The present data suggest that focal adhesion kinase phosphorylation, phosphoinositide 3-kinase-, mitogen-activated protein kinase- and Rho kinase activations are involved in RANTES/CCL5 pro-tumoral effects on Huh7 cells. Interference with oligomerization of the chemokine reduced RANTES/CCL5-mediated cell chemotaxis. This study also indicates that SDC-1 and -4 may be required for HepG2, Hep3B and Huh7 human hepatoma cell migration, invasion or spreading induced by the chemokine. These results also further demonstrate the involvement of glycosaminoglycans as the glycosaminoglycan-binding deficient RANTES/CCL5 variant, in which arginine 47 was replaced by lysine, was devoid of effect.

General significance

The modulation of RANTES/CCL5-mediated cellular effects by targeting the chemokine-syndecan interaction could represent a new therapeutic approach for hepatocellular carcinoma.     

Unrestricted somatic stem cells from human umbilical cord blood grow in serum-free medium as spheres

Background  

Human umbilical cord blood-derived unrestricted somatic stem cells (USSCs), which are capable of multilineage differentiation, are currently under investigation for a number of therapeutic applications. A major obstacle to their clinical use is the fact that in vitro expansion is still dependent upon fetal calf serum, which could be a source of pathogens. In this study, we investigate the capacity of three different stem cell culture media to support USSCs in serum-free conditions; HEScGRO™, PSM and USSC growth medium^ACF. Our findings demonstrate that USSCs do not grow in HEScGRO™ or PSM, but we were able to isolate, proliferate and maintain multipotency of three USSC lines in USSC growth medium^ACF.     

Immunotherapy of cancer: promise and reality

The notion that the immune system regulates cancer development is now well established. An overwhelming amount of data from animal models, together with compelling data from human patients, indicate that the immune system is instrumental in scanning and irradicating tumors. Analysis of individuals with congenital or acquired immunodeficiencies or patients undergoing immunosuppressive therapy has documented a highly elevated incidence of virally induced malignancies and cancers compared with immunocompetent individuals [1-3]. During the last decade, thanks to the breakthoughts in understanding the molecular mechanisms responsible for immune activation, the tumor antigen identification, the dendritic cell biology, the immunogenecity of tumors, the immune escape mechanisms, the host-tumor relationship, we are facing a new area of tumor immunotherapy. The basic advances were translated in therapeutical applications and have changed the view of immunotherapy from "a dream scenario" to a clinical fourth modality to cancer treatments. Multiple cancer trials using active immunization with vaccines or adoptive immunotherapy have been conducted with only very limited success. There are still a number of issues that still need to be resolved including a better understanding of immune escape mechanisms. Cancer vaccines continue to be evaluated and may lead to the emergence of clinically useful new treatments. A comprehensive approach to define the intricate molecular program initiated by tumor cells to resist to escape and the immune system of the host may help in breaking down the barriers to a more adapted cancer immunotherapy.     

Phylogenetic evaluation of anamorphic species of <Emphasis Type="Italic">Cirrenalia</Emphasis> and <Emphasis Type="Italic">Cumulospora</Emphasis> with the description of eight new genera and four new species

Four new helicoid anamorphic fungi collected from marine habitats in Egypt and Japan are described. Three marine and one terrestrial Cirrenalia species along with two Cumulospora species and the four new fungi were sequenced for LSU and SSU rDNA. Phylogenetic analyses of the generated sequences, along with those from GenBank, confirmed the polyphyly of the genera Cirrenalia and Cumulospora, and new genera are erected to accommodate the displaced species. Eight new genera, four new species and six new combinations are made: 1. Halazoon anam.-gen. nov. (Halazoon melhae sp. nov., H. fuscus for Cirrenalia fusca), 2. Moheitospora anam.-gen. nov. (Moheitospora fruticosae sp. nov., M. adarca for Cirrenalia adarca), 3. Moleospora anam.-gen nov. (Moleospora maritima sp. nov.), and 4. Glomerulispora anam.-gen. nov. (Glomerulispora mangrovis sp. nov); Cirrenalia pygmea, Cirrenalia tropicale and Cumulospora varius are transferred to the new genera, 5. Hydea anam.-gen. nov, 6. Matsusporium anam.-gen. nov., and 7. Moromyces anam.-gen. nov., respectively. These genera can be assigned to the order Lulworthiales, TBM (Torpedospora/Bertia/Melanospora) clade, while Cirrenalia macrocephala is nested within the order Halosphaeriales. Few morphological characters delineate the genera and species assigned to the Lulworthiales and this aspect is discussed in relation to the molecular data. The phylogenetic position of the terrestrial species, Cirrenalia japonica, shows that it is a member of the order Pleosporales, and a new genus, 8. Hiogispora anam.-gen. nov. is proposed for the fungus.     

Evidence of Cannibalism in Macrolophus pygmaeus, a Natural Enemy of Whiteflies

Cannibalism and the effects of host plant, sex, time and food resources on its expression were studied for the zoophagous mirid Macrolophus pygmaeus Wagner (Hemiptera: Miridae). Cannibalistic behaviour was studied by offering 5 conspecific larvae (first instar) to newly emerging adults. Four treatments were studied: without water, with water only, with a host plant (tobacco) and with both a host plant and prey (eggs of Ephestia kuehniella). Cannibalism was observed in all treatments. In the “host plant + eggs of E. kuehniella” treatment, very few individuals displayed cannibalistic behaviour. The proportion of cannibalism was only reduced when eggs of E. kuehniella were offered. Water (free or via a host plant) was very important for both survival and feeding. The cannibalistic behaviour of M. pygmaeus should be taken into account when planning a release strategy in the context of biological control.