LyP: lymphomatoid papulosis INTRODUCTION Lymphomatoid papulosis (LyP) is an indolent skin disease characterized by chronic, recurrent, selfhealing papules and nodules with histologic findings suggestive of malignant lymphoma. LyP is classified as a CD301 cutaneous lymphoproliferative disorder according to the 2005 World Health Organization/ European Organisation for Research and Treatment of Ca...

The ability to selectively deliver compounds into atherosclerotic plaques would greatly benefit the detection and treatment of atherosclerotic disease. We describe such a delivery system based on a 9-amino acid cyclic peptide, LyP-1. LyP-1 was originally identified as a tumor-homing peptide that specifically recognizes tumor cells, tumor lymphatics, and tumor-associated macrophages. As the rece...

The protein tyrosine phosphatase LYP, a key regulator of TCR signaling, presents a single nucleotide polymorphism, C1858T, associated with several autoimmune diseases such as type I diabetes, rheumatoid arthritis, and lupus. This polymorphism changes an R by a W in the P1 Pro rich motif of LYP, which binds to CSK SH3 domain, another negative regulator of TCR signaling. Based on the analysis of ...

The lymphoid-specific tyrosine phosphatase (Lyp) has generated enormous interest because a single-nucleotide polymorphism in the gene (PTPN22) encoding Lyp produces a gain-of-function mutant phosphatase that is associated with several autoimmune diseases, including type I diabetes, rheumatoid arthritis, Graves disease, and systemic lupus erythematosus. Thus, Lyp represents a potential target fo...

Lymphoid tyrosine phosphatase (LYP) and C-terminal Src kinase (CSK) are negative regulators of signaling mediated through the T-cell antigen receptor (TCR) and are thought to act in a cooperative manner when forming a complex. Here we studied the spatiotemporal dynamics of the LYP-CSK complex in T cells. We demonstrate that dissociation of this complex is necessary for recruitment of LYP to the...

A C1858T (R620W) variation in the PTPN22 gene encoding the tyrosine phosphatase LYP is a major risk factor for human autoimmunity. LYP is a known negative regulator of signaling through the T cell receptor (TCR), and murine Ptpn22 plays a role in thymic selection. However, the mechanism of action of the R620W variant in autoimmunity remains unclear. One model holds that LYP-W620 is a gain-of-fu...

Positional cloning of lymphopenia (lyp) in the BB rat revealed a frameshift mutation in Gimap5, a member of at least seven related GTPase Immune Associated Protein genes located on rat chromosome 4q24. Our aim was to clone and sequence the cDNA of the BB diabetes prone (DP) and diabetes resistant (DR) alleles of all seven Gimap genes in the congenic DR.lyp rat line with 2 Mb of BB DP DNA introg...

Lyp-1 is a nine amino acid cyclic peptide, which has specificity of tumor cells especially on breast cancer cells1-4. LyP-1 is not only a special marker for the tumor endothelial cells but also specific to the tumor lymphatic endothelia to which vascular peptides (F3, CREKA peptide, RGD peptides) are not specific5. It has been shown that following iv administration of LyP-1, the peptide accumul...

The ability to detect and quantify macrophage accumulation can provide important diagnostic and prognostic information for atherosclerotic plaque. We have previously shown that LyP-1, a cyclic 9-amino acid peptide, binds to p32 proteins on activated macrophages, facilitating the visualization of atherosclerotic plaque with PET. Yet, the in vivo plaque accumulation of monomeric [(18)F]FBA-LyP-1 ...

LyP-1 is a peptide selected from a phage-displayed peptide library that specifically binds to tumor and endothelial cells of tumor lymphatics in certain tumors. Fluorescein-conjugated LyP-1 and a related peptide, LyP-1b, strongly accumulated in primary MDA-MB-435 breast cancer xenografts and their metastases from i.v. peptide injections, allowing visualization of orthotopic tumors in intact mic...