Antigen Distribution in Mucocutaneous Biopsies of Human Paracoccidiomycosis

Abstract

The authors studied the distribution of Paracoccidioides brasiliensis antigen(s) in human skin and oral mucosa. In biopsies obtained from untreated patients showing the chronic form of the disease, the authors demonstrated the P. brasiliensis antigen using two polyclonal immune sera raised in rabbits, one against the exoantigens of P. brasiliensis and the other against a 43-kDa glycoprotein. Langerhans' cells were detected through double immunolabeling using an anti-S 100 protein monoclonal antibody. Double labeling immunohistochemistry showed that both of the immune sera labeled the yeast cells in the center of the granuloma and those transmigrating through the epithelial layer equally well. Granulomas exhibited the P. brasiliensis antigen permeating cells, mainly at the periphery of the granulomatous inflammation. The P. brasiliensis antigen(s) accumulated in the macrophages but not in the Langerhans' cells. P. brasiliensis antigens, detected by antiserum against parasite exoantigens, were also deposited between basal keratinocytes, but not in the granular cells, in 47% of the biopsies. P. brasiliensis antigens, as assessed by immunoelectron microscopic techniques, are present in the cytoplasm of the yeast cells in the host tissues. Antigens are transported to the cell membrane and later excreted through the cell wall. Antigenic deposits are also seen at the fungus-host interface. Int J Surg Pathol 3(3):181-188, 1996

Characterization of inflammatory cells in oral paracoccidioidomycosis

“…Studies have also reported a reduced number of epidermal Langerhans cells (LCs) with short and irregular dendrites when compared with the normal skin (Gimenez et al , 1987; Pagliari and Sotto, 2003). In addition, Sandoval et al (1996) did not detect Pb antigens in the cytoplasm of LCs, suggesting that they would not be capable of presenting fungal antigens efficiently. Conversely, the yeast has been described inside FXIIIa+ dermal dendrocytes, another group of dendritic cells with characteristics similar to LCs (Pagliari and Sotto, 2002).…”

Antigen distribution and antigen‐presenting cells in skin biopsies of human chromoblastomycosis

“…Antigen(s) were also observed in the cytoplasm of proliferated and hypertrophic FXIIIa + DD. Similar to paracoccidiodomycosis 11,16 both probably function as antigen‐ presenting cells (APCs) in chromoblastomycosis. Langerhans' cells in the dermis appeared to be conspicuous and occasionally were part of the granulomatous inflammation.…”

An overview of the immunopathology of human paracoccidioidomycosis

“…In fact, macrophages are considered central to the anti-Pb immunity [36]. Neutrophil accumulation has been described in the early phase of the immune response, either permeating the granulomatous reaction or forming microabscesses within them [37][38][39][40]. These cells have been shown to also exert in vitro anti-Pb activity [41][42][43][44], but their in vivo role in the host defense against the fungus remains to be determined.…”