CXCL14‐like immunoreactivity in somatostatin‐producing cells of the Japanese quail (Coturnix japonica) pancreas

Abstract

This study examines chemokine CXCL14‐like peptide distribution in the Japanese quail (Coturnix japonica) pancreas using a specific anti‐human CXCL14 antibody. CXCL14‐immunoreactive cells were observed in the pancreatic islet peripheral region. The staining was abolished after pre‐absorbing the antibody with recombinant human CXCL14. CXCL14‐immunoreactive cells were immuno‐positive for somatostatin, but not glucagon and insulin. CXCL14 secreted from somatostatin‐producing cells might participate in insulin secretion modulation together with somatostatin. In addition, CXCL14 might participate in glucose homeostasis in co‐operation with somatostatin and growth hormone.

CXCL14 immunoreactivity is localized in pituitary GH‐producing cells and in median eminence somatostatin‐containing fibres of the Japanese quail (Coturnix japonica)

“…In addition, CXCL14 is also co‐localized with somatostatin in the axolotl brain (unpublished data). On the other hand, CXCL14‐immunoreactive cells correspond to somatostatin‐producing cells in mouse (Atanes et al, 2019; Suzuki & Yamamoto, 2015) and quail (Suzuki & Yamamoto, 2023) pancreatic islets. The co‐localization of CXCL14 and somatostatin in the nervous system and pancreatic islets may be a widely conserved phenomenon in vertebrates.…”

“…Immunostaining was performed as previously described (Suzuki & Yamamoto, 2023). Briefly, sections were washed overnight in 0.1 M PB (pH 7.4) containing 0.9% saline (PBS) and incubated with rabbit anti‐human CXCL14 antibody (No.…”

“…500‐P237; PeproTech Inc., Rocky Hill, NJ, USA) diluted to 0.5 μg/mL in PBS containing 1% bovine serum albumin and 0.3% Triton X‐100 (PBS‐BSAT) for 24 h at 4°C. This antibody has been used in a previous study that described the CXCL14 distribution in quail pancreatic islets (Suzuki & Yamamoto, 2023). After washing in PBS, sections were incubated with biotinylated goat anti‐rabbit IgG antibody (BA‐1000; Vector Laboratories, Burlingame, CA, USA) diluted 1:100 in PBS‐BSAT for 1 h at room temperature.…”

“…C-X-C motif chemokine ligand 14 (CXCL14) was originally isolated from human tumour cells such as BRAK (Hromas et al, 1999), BMAC (Sleeman et al, 2000) and MIP-2γ (Cao et al, 2000). CXCL14 is a unique 77 amino acid peptide that plays an important function not only in the immune system but also in the nervous and endocrine systems (Atanes et al, 2019;Nara et al, 2007;Suzuki et al, 2017Suzuki et al, , 2022Suzuki & Yamamoto, 2015, 2023Yamamoto et al, 2011Yamamoto et al, , 2020. A previous molecular biological study demonstrated a high degree of conservation of CXCL14 in vertebrates (Hara & Nakayama, 2009), suggesting that CXCL14 is an essential bioactive peptide for vertebrates.…”

Amylin‐like immunoreactivity in the extra‐islet peptide YY‐producing and glucagon‐immunoreactive cells in Japanese quail pancreas

“…We performed the immunostaining as described previously (Suzuki & Yamamoto, 2023). Briefly, we washed the sections overnight in 0.1 M PB (pH 7.4) containing 0.9% saline (PBS) and incubated them with the primary antibody, that is, rabbit anti‐rat amylin serum (Table 1), diluted in PBS containing 1% bovine serum albumin (A 7906; Sigma‐Aldrich, Saint Louis, MO, USA) and 0.3% Triton X‐100 (PBS‐BSAT), for 24 h at 4°C.…”