CD26 is expressed on a restricted subpopulation of dendritic cells in vivo

Abstract

Two major sub‐populations of dendritic cells (DC) are present in afferent lymph draining the skin of cattle distinguished by expression of signal regulator protein alpha (SIRPα). The SIRPα– population expresses the uncharacterized bovine WC10 antigen (Ag). Initial N‐terminal sequencing of the WC10 protein purified by affinity chromatography showed significant homology with human CD26. A cDNA encoding bovine CD26 was cloned and the recombinant molecule expressed in COS‐7 cells. Transfectants abrogated the ability of macrophage‐derived chemokine (MDC) to cause a calcium flux in bovine PBMC indicating enzymatic activity characteristic of CD26. They also stained with WC10 monoclonal antibody confirming that the Ag is CD26. This is the first description of CD26 expression by DC in vivo or in vitro. It is expressed on a sub‐population of ex vivo DC in afferent lymph draining the skin and on sub‐populations of DC isolated from prescapular and mesenteric lymph nodes draining the skin or intestine, respectively. CD26 is an exopeptidase with specificity for motifs within the receptor‐binding domain of several chemokines including MDC. CD26 mediated truncation of MDC affects the Th cell response effected by the chemokine and may produce a Th1 bias. Transcripts for MDC were present in both CD26+ and CD26– DC, thus CD26mediated modification of MDC may bias the immune response induced in naive T cells by DC.

Differential Effects of Viral Vectors on Migratory Afferent Lymph Dendritic CellsIn VitroPredict Enhanced ImmunogenicityIn Vivo

“…In cattle, various populations of skin-draining ALDC have been described by their differential expression of SIRP␣ (CD172a), CD11a, CD26, and CD13 (4,19,20,30). These populations have been shown to interact with and stimulate T cells differently and have differential cytokine secretion profiles (25,30,43,54).…”

Antigen presenting cells in mucosal sites of veterinary species

“…The significance of the presence of CD26 in this DC subset was investigated [31]: CD26 is an exopeptidase with specificity for motifs within the receptor-binding domain of several chemokines including monocyte derived chemokine (MDC). CD26 mediated truncation of MDC affects the Th cell response affected by the chemokine and may produce a Th1 bias.…”

“…In cattle, the presence of CD26 on the CD4-SIRPα-subset has also been demonstrated, and a greater proportion of this subset was shown in lymph draining the gut mucosa. in comparison to draining lymph from skin [31]. In addition, the bovine homologue to human CD205 was shown to be present on both DC subsets, thereby confirming their DC nature [32].…”

“…Studies in this species have been helped by the crossreactive CD26 antibody raised to bovine CD26 [31]. Here, a comparison between lymph draining from the head mucosa (cervical DC (CerDC)) versus cutaneous microenvironments on the constitutive DC release was made, again by lymph cannulation [25].…”

Viral Semaphorin Inhibits Dendritic Cell Phagocytosis and Migration but Is Not Essential for Gammaherpesvirus-Induced Lymphoproliferation in Malignant Catarrhal Fever

“…The percentage of migrated cells was calculated by the following formula for each subset: [(number of migrated cells)/(total number of input cells)] ϫ 100. The CD1b ϩ and CD26 ϩ cells subsets were stained with mouse MAbs against CD1b (mouse IgG2a, clone TH97A) and CD26 (mouse IgG1, clone CC69), followed by biotin-labeled rat anti-IgG2a and PE-labeled rat anti-mouse IgG1 and a final incubation with streptavidin-APC (BD Biosciences) (38,39). Histological analysis.…”