CXC chemokine ligand (CXCL)9, CXCL10 and CXCL11 direct chemotaxis of mainly T cells and NK cells through activation of their common CXC chemokine receptor (CXCR)3. They are inactivated upon NH₂-terminal cleavage by dipeptidyl peptidase IV/CD26. In the present study, we found that different glycosaminoglycans (GAGs) protect the CXCR3 ligands against proteolytic processing by CD26 without directl...

The serine protease CD26/dipeptidyl-peptidase IV (CD26/DPP IV) and chemokines are known key players in immunological processes. Surprisingly, CD26/DPP IV not only removed the expected Gly1-Pro2 dipeptide from the NH2 terminus of macrophage-derived chemokine (MDC) but subsequently also the Tyr3-Gly4 dipeptide, generating MDC(5-69). This second cleavage after a Gly residue demonstrated that the s...

BACKGROUND Psoriasis is known to affect 2-3% of the population and can be considered an organ-specific autoimmune disease. CD26/dipeptidyl-peptidase IV (DPP-IV) is a membrane-bound protease with diverse properties. In theory, the expression of CD26/DPP-IV has common grounds with three principal key players of the psoriatic pathogenesis: keratinocytes, T cells and cytokines. OBJECTIVES To asse...

CD26, a 110 kDa cell surface glycoprotein, exhibits dipeptidyl peptidase IV (DPPIV; EC 3.4.14.5) enzyme activity and plays an important role in T cell co-stimulation. In the present study, the function of CD26/DPPIV in transendothelial migration was examined using beta-chemokines as chemoattractants. When soluble recombinant CD26 (sCD26/DPPIV+) was added to the transendothelial chemotaxis syste...

BACKGROUND Chronic Fatigue Syndrome (CFS) studies from our laboratory and others described decreased natural killer cell cytotoxicity (NKCC) and elevated proportion of lymphocytes expressing the activation marker, dipeptidyl peptidase IV (DPPIV) also known as CD26. However, neither these assays nor other laboratory tests are widely accepted for the diagnosis or prognosis of CFS. This study soug...

CD26 and CD40 ligand (CD40L) are surface molecules on human activated T lymphocytes that play a critical role in the regulation of lymphopoiesis. Both molecules are expressed on a restricted fraction of human T-cell non-Hodgkin's lymphomas (NHL)/leukemias; however, little is known about their functional and/or clinical significance in these disorders. In this study, the pattern of expression of...

CD26 is a 110 kDa surface glycoprotein with intrinsic dipeptidyl peptidase IV (DPPIV, EC 3.4.14.5) activity that is expressed on numerous cell types and has a multitude of biological functions. CD26 role in immune regulation has been extensively characterized, with recent findings elucidating its linkage with signaling pathways and structures involved in T-lymphocyte activation as well as antig...

We studied dipeptidyl peptidase IV (DPP-IV, CD26) expression in different T helper cells and serum soluble DPP-IV/sCD26 levels in rheumatoid arthritis (RA) patients, correlated these with disease activity score (DAS), and examined how they were affected by different therapies, conventional or biological (anti-TNF, anti-CD20 and anti-IL6R or Ig-CTLA4). The percentage of CD4+CD45R0+CD26- cells wa...

A neural cell detection system (NCDS) for the automatic quantitation of fluorescent lymphocytes in tissue sections was used to analyze CD26 expression in muscle-invasive T-cells. CD26 is a cell surface dipeptidyl-peptidase IV (DPP IV) involved in co-stimulatory activation of T-cells and also in adhesive events. The NCDS system acquires visual knowledge from a set of training cell image patches ...

Chemokines are proinflammatory cytokines that play a role in leukocyte migration and activation. Recent reports showed that RANTES (regulated on activation normal T-cell expressed and secreted chemokine), eotaxin, macrophagederived chemokine (MDC), and stromal cell–derived factor-1 (SDF-1) are NH2terminally truncated by the lymphocyte surface glycoprotein and protease CD26/ dipeptidyl peptidase...