Immunological and histopathological characterization of cutaneous candidiasis.

Chronic mucocutaneous candidiasis constitutes a heterogeneous group of syndromes, characterized by non-invasive infection of the skin, nails and mucosal membranes by the fungus Candida spp. Although symptoms are heterogeneous, in all cases there is a reduction in protective cytokines, favouring the development of disease. The normal role of cytokines in skin lesions is not well understood. The present study aimed to investigate the progression of disease, understand specific cellular and molecular components involved in immunity to Candida albicans and determine the balance between pro- and anti-inflammatory cytokines over the course of cutaneous infection in immunocompetent mice. BALB/c mice (five per group) were inoculated with 5 × 10(6)C. albicans pseudohyphae in the deep dermis of the paw and analysed over 1-14  days post-infection. The contralateral paws were used for negative controls. Haematoxylin and eosin staining of skin sections during C. albicans infection was performed to analyse structural modifications to the epidermis such as hyperplasia, and infiltration of neutrophils and fibroblasts in the dermis. The cytokine populations were determined by capture ELISA using popliteal lymph node tissue. Pro-inflammatory cytokines (IL-6, TNF-α, IL-12, IFN-γ and IL-17) were detected at significant levels during the initial phase of cutaneous infection and correlated with the rapid elimination of C. albicans. Anti-inflammatory cytokines (IL-13, IL-4, IL-10 and transforming growth factor-ß) were detected on day 4 post-infection, and prevented exacerbation of inflammation and participated in healing of lesions. Thus, a balance between pro- and anti-inflammatory cytokines was fundamental for the resolution of infection. Importantly, these findings broaden our understanding of the immune mechanisms involved in chronic cutaneous candidiasis.

Meduloblastoma: aspectos histológicos, moleculares e imunopatológicos / Medulloblastoma: histological, molecular and immunopathological aspects

O meduloblastoma é um tumor cerebelar caracterizado como tumor neuroectodérmico primitivo prevalente em crianças, sendo as do sexo masculinos as mais afetadas. Com relação à classificação histológica,existem cinco variações: clássico, desmoplásico, anaplásico, células gigantes e de extensa nodularidade. Muitos estudos relatam que a patogênese do meduloblastoma está relacionada com mutações em fatores de crescimento do SNC, sendo que as principais vias envolvidas são: Sonic Hedgehog, NOTCH, WNT eOTX. Ainda, com respeito à imunologia, pacientes com meduloblastoma apresentaram alta taxa de IFN-γno soro e células TH17 no sangue periférico, e foi observado que o TGF-β tem sido associado à estimulação mitogênica, o que pode estar relacionado à patogênese da doença. A predominância de uma resposta TH1 relacionada à sobrevivência também foi relatada. O desenvolvimento terapêutico para o meduloblastoma,apesar de limitado, é significativo, uma vez que este vem apresentando melhora na sobrevida de seus pacientes. Entretanto, um maior conhecimento dos mecanismos envolvidos na imunopatogênese é necessário para o desenvolvimento de novos fármacos e formas de tratamento.

Medulloblastoma is a cerebellar tumor classified as primitive neuroectodermal tumor and is prevalent in children, especially male. With regard to histological classification, there are five variations: classical, desmoplastic, anaplastic, large-cell variant and with extensive nodularity. Several studies have reported that medulloblastoma pathogenesis is related to mutations in CNS growth factors, and the main pathways involved are Sonic Hedgehog, NOTCH, WNT, and OTX. Also regarding the immunology, patients with medulloblastoma have a high serum concentration of INF-γ and TH17 cells in peripheral blood, and it was observed that TGF-β has been associated with mitogenic stimulation, and possibly associated to the pathogenesis of this disease. The prevalence of a TH1 response related to the survival was also described. The development of therapies for medulloblastoma treatment, though limited, is significant, as they resultin an improvement in the patient’s survival. However, a better understanding of the mechanism involvedin its immunopathogenesis is still necessary for the development of new drugs and ways of treatment.