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Abstract Background The tumor draining lymph node concept was first described in penile cancer for staging. Immunohistochemistry and histopathology evaluations are routinely used in clinical practice to examine lymph nodes for metastasis. However, these methods are time-consuming with low diagnostic accuracy and micro-metastases might be missed. In this study, we aim to evaluate detection of metastatic cells in draining lymph nodes by flow cytometry. Methods To assess the sensitivity of micro-metastasis detection by FACS (Fluorescence-activated cell sorting), HeLa cells were titrated into Peripheral blood mononuclear cells (PBMCs) and expression of pan-cytokeratin AE1/AE3 was analyzed. Single cell suspensions were separately prepared from 10 regional lymph nodes obtained from 5 patients with invasive penile cancer undergoing radical surgery and lymph node dissection. Lymph node dereived cells were examined for cell surface expression of EpCAM, E-cadherin and intracellular expression of pan-cytokeratin AE1/AE3 by FACS. Results Ten lymph nodes from 5 penile cancer patients were investigated in a head-to-head comparison between FACS and pathology examination of sections. All metastatic lymph nodes verified by pathology examination were also identified by FACS. Two additional lymph nodes with micro-metastases were diagnosed by FACS only. Conclusions FACS analyses of pan-cytokeratin AE1/AE3 stained single cells from tumor draining lymph nodes can be used to detect micro-metastases in patients with penile cancer patients.

Microbial products are sensed through Toll-like receptors (TLRs) and trigger a program of dendritic cell (DO maturation that enables DCs to activate T cells. Although an accepted hallmark of this response is eventual down-regulation of DC endocytic capacity, we show that TLR ligands first acutely stimulate antigen macropinocytosis, leading to enhanced presentation on class I and class II major histocompatibility complex molecules. Simultaneously, actin-rich podosomes disappear, which suggests a coordinated redeployment of actin to fuel endocytosis. These reciprocal changes are transient and require p38 and extracellular signal-regulated kinase activation. Thus, the DC actin cytoskeleton can be rapidly mobilized in response to innate immune stimuli to enhance antigen capture and presentation., Immature DCs respond to pathogen-derived products (1, 2) by initiating a program of maturation that induces their migration to lymphoid organs and culminates in the enhanced expression of major histocompatibility [...]

NF-[kappa]B signaling plays an important role in skin development and epidermal growth control. Moreover, inhibition of NF-[kappa]B signaling in murine epidermal keratinocytes in vivo, by expression of a keratin 5 (K5)-directed superrepressor form of inhibitor of NF-[kappa]B (I[kappa]B[alpha]), results in an inflammatory response characterized by a massive dermal infiltration of neutrophils, epidermal hyperplasia, and a rapid development of aneuploid squamous cell carcinomas (SCC). We now show that by crossing KS-I[kappa]B[alpha] mice onto a tumor necrosis factor receptor 1(Tnfr1)-null background, both the inflammatory and the tumorigenic responses are blocked. The specificity of the block is illustrated by the fact that KS-I[kappa]B[alpha] mice lacking the IL-1 receptor type 1 (II1r1) develop inflammation and squamous ceil carcinomas. Reconstitution of lethally irradiated K5-I[kappa]B[alpha]/Tnfr[1.sup.-/-] mice with Tnfr[1.sup.+/-] bone marrow does not induce the inflammatory or the tumorigenic phenotype, indicating a critical dependence on Tnfr1-mediated signaling in skin cells or nonimmune cells. Our results suggest a critical role of local Tnfr1-mediated signaling and associated inflammatory response cooperating with repressed keratinocyte NF-[kappa]B signaling in driving skin cancer development.

B cells and dendritic cells, lacking functional Wiskott-Aldrich syndrome protein (WASP), have aberrant formation of membrane protrusions. We hypothesized that protrusions may play a role in antigen presentation, and consequently, that impaired antigen presentation may be an underlying factor of the immune deficiency in patients with Wiskott-Aldrich syndrome. In this paper, we investigated the antigen presentation capacity of B cells and dendritic cells from WASP knockout mice, using soluble and particulate antigen, to CD4[SUP+] T cells from T-cell receptor transgenic DO11.10 mice. As antigen we used soluble ovalbumin (OVA), a peptide thereof (amino acids 323-339) or bacteria expressing OVA. We tound that WASP-deficient B cells and dendritic cells efficiently processed and presented soluble OVA protein as well as its peptide in vitro, inducing proliferation and cytokine production from CD4[SUP+] T cells. Antigen presentation of soluble protein was efficient also in vivo, because immunization of WASP-deficient mice with OVA elicited proliferation of transferred, fluorescent-labelled, CD4[SUP+] T cells. Although we could detect uptake of bacteria in dendritic cells, processing and presentation of bacterial-expressed OVA was impaired in WASP-deficient dendritic cells. In conclusion, our data suggest that WASP is not needed for processing and presentation of soluble antigen, but that efficient presentation of particulate antigen require WASP. [ABSTRACT FROM AUTHOR]