Interleukin 10 induced augmentation of delayed-type hypersensitivity (DTH) enhances Mycobacterium bovis bacillus Calmette-Guérin (BCG) mediated antitumour activity

The role of interleukin 10 in the pathogenesis and potential treatment of skin diseases

Interleukin 10 (IL-10) is a key cytokine produced by a multitude of immune effector cells and possesses distinct regulatory effects on immune functioning in the skin. In this article we report the current understanding of the immunobiology of IL-10 and identify the role of IL-10 in cutaneous infection as well as in autoimmune and neoplastic processes. We reviewed the literature to examine the function of IL-10 in different cutaneous disorders. IL-10 can influence and potentially treat T1/T2 differentiation, antigen-presenting cell functioning, antigen-presenting cell-mediated T-cell activation, and T-cell, B-cell, and mast cell growth and differentiation that is aberrant in various disease processes. The literature consensus is that the multitude of effects of IL-10 contribute to the pathogenesis of different skin disorders. In certain circumstances IL-10 could represent novel therapeutic approaches to treating cutaneous diseases.

LEARNING OBJECTIVE

At the conclusion of this learning activity, participants should be acquainted with the role of IL-10 in many infectious diseases, autoimmune skin disease, inflammatory processes, and malignancy. Its possible role in the resolution of various skin diseases should be better understood.

Polarisation of a T-helper cell immune response by activation of dendritic cells with CpG-containing oligonucleotides: a potential therapeutic regime for bladder cancer immunotherapy

Intravesical bacillus Calmette–Guerin (BCG) is a treatment for transitional cell carcinoma (TCC) and carcinoma in situ (cis) of the urinary bladder, but some patients remain refractory. The mechanism of cancer clearance is not known, but T cells are thought to play a contributory role. Tissue dendritic cells (DCs) are known to initiate antigen-specific immune responses following activation of receptors, which recognise molecular patterns on the surface of microorganisms. A family of these receptors, the toll-like receptors (TLRs), are also crucial for activating DC to produce cytokines that polarise the T-cell response towards a T helper (Th)1 or Th2 phenotype. This study compared the potential of intact BCG to activate DC with that of the defined TLR4 ligand lipopolysaccharide (LPS) and the TLR9 ligand CpG-oligonucleotide. It was found that all three stimuli efficiently activated normal DC, but cells expressing a mutant TLR4 responded poorly to stimulation with LPS. Importantly, stimulation with BCG induced both IL-12 and IL-10, suggesting subsequent development of a poorly focused T-cell immune response containing both Th1 and Th2 immune function. By contrast, LPS- and CpG-oligonucleotides induced only IL-12, indicating the potential to produce a Th1 response, which is likely to clear cancer most efficiently. Given the toxicity of LPS, our data suggest that CpG-oligonucleotides may be beneficial for intravesical therapy of bladder cancer.

The current status of intravesical therapy for superficial bladder cancer

PURPOSE OF REVIEW

To analyse recent advances in intravesical instillation therapy for superficial bladder cancer.

RECENT FINDINGS

Although intravesical bacillus Calmette-Guérin has been used for many years in the treatment of superficial bladder cancer, its mechanism of action remains unclear, its poor tolerance remains a problem, the prediction of its efficacy has still to be validated, and its long-term effects on progression and survival are controversial. The exact timing and place of intravesical chemotherapy needs to be better defined, as well as the place of some new molecules. Finally, new approaches need to be explored for overcoming the limitations of the usual intravesical agents.

SUMMARY

No dramatic advances have been made in understanding the mechanisms of action of bacillus Calmette-Guérin during the past year. However, a careful dissection of this complex immunological pathway continues and immunological criteria are promising for predicting the response to bacillus Calmette-Guérin. Evidence has been accumulating to suggest that a dose reduction during the initial treatment remains effective and reduces side-effects. In addition, bacillus Calmette-Guérin maintenance therapy is useful for high-risk patients. However, long-term tolerance remains an important issue, and the optimal protocol has not yet been defined. On the other hand, it has been proved that intravesical chemotherapy, when administered early after transurethral resection, is effective in preventing frequent recurrences, whereas maintenance chemotherapy is ineffective. Finally, new approaches, including instillations of activated immune cells or targeted gene therapy, are being explored.