"CATH-2 and LL-37 were synthesized by Fmoc-chemistry at CPC Scientific (Sunnyvale, CA)."
Abstract
Activation of the immune system needs to be tightly regulated to provide protection against infections and, at the same time, to prevent excessive inflammation to limit collateral damage to the host. This tight regulation includes regulating the activation of TLRs, which are key players in the recognition of invading microbes. A group of short cationic antimicrobial peptides, called cathelicidins, have previously been shown to modulate TLR activation by synthetic or purified TLR ligands and may play an important role in the regulation of inflammation during infections. However, little is known about how these cathelicidins affect TLR activation in the context of complete and viable bacteria. In this article, we show that chicken cathelicidin-2 kills Escherichia coli in an immunogenically silent fashion. Our results show that chicken cathelicidin-2 kills E. coli by permeabilizing the bacterial inner membrane and subsequently binds the outer membrane-derived lipoproteins and LPS to inhibit TLR2 and TLR4 activation, respectively. In addition, other cathelicidins, including human, mouse, pig, and dog cathelicidins, which lack antimicrobial activity under cell culture conditions, only inhibit macrophage activation by nonviable E. coli In total, this study shows that cathelicidins do not affect immune activation by viable bacteria and only inhibit inflammation when bacterial viability is lost. Therefore, cathelicidins provide a novel mechanism by which the immune system can discriminate between viable and nonviable Gram-negative bacteria to tune the immune response, thereby limiting collateral damage to the host and the risk for sepsis.
SOCIAL MEDIA
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Development of a selective, sensitive and robust oxyntomodulin dual monoclonal antibody immunoassay.
Umberger, T.S., Ming, W., Cox, J.M., Konrad, R.J. and Siegel, R.W. Bioanalysis 14, no. 18 (2022): 1229-1239.
- Lilly Research Laboratories, Eli Lilly & Company, Indianapolis, IN46285, USA
Human K2 EDTA and P800 plasma (500 μl) was spiked with proglucagon 33–61, 35–61 and 36–61 stable-isotope-labeled internal standard peptides (CPC Scientific, custom order) and diluted with I buffer (25 mmol/l Tris-HCl, 25 mmol/l HEPES, 300 mmol/l NaCl, 0.1% (v/v) octyl β-D-glucopyranoside, pH 7.5).
Line, J.E.; Seal, B.S.; Garrish, J.K. Appl. Microbiol. 2022, 2, 688–700.
Peptides were synthesized using standard solid-phase(Fmoc) chemistry with a peptide synthesizer (CPC Scientific Inc., Sunnyvale, CA 94089,USA, C12K-2β12 [..]
Kirk, N.S., Chen, Q., Wu, Y.G., Asante, A.L., Hu, H., Espinosa, J.F., Martínez-Olid, F., Margetts, M.B., Mohammed, F.A., Kiselyov, V.V. and Barrett, D.G. Nature Communications 13, no. 1 (2022): 5695.
- Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN 46285, USA.
Peptides were synthesized under contract by CPC Scientific, except for the N-terminally acetylated version of IM172N22 and the Glu3Arg, Glu3Ala, Glu4Arg, Glu4Ala, Glu5Ala, Glu5Arg, Trp6Ala, Gln8Ala, Ile9Ala, Glu10Ala, Glu10Arg and Tyr14Ala mutants of IM172N22
Coskun, T., Urva, S., Roell, W.C., Qu, H., Loghin, C., Moyers, J.S., O’Farrell, L.S., Briere, D.A., Sloop, K.W., Thomas, M.K. and Pirro, V. Cell Metabolism 34, no. 9 (2022): 1234-1247.
- Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN 46285, USA
Homologous and heterologous competition experiments were performed with non-radioactive peptide analogues[127I]-Tyr1-GIP(1-42) and [127]-Tyr10-GIP(1-42) to ensure quantification of the high-affinity binding site of the GIPR. Peptide analogues were generated using synthetic [127I]-Tyr amino acid building blocks (CPC Scientific).
Cecil, D.L., Curtis, B., Gad, E., Gormley, M., Timms, A.E., Corulli, L., Bos, R., Damle, R.N., Sepulveda, M.A. and Disis, M.L. Scientific Reports 12, no. 1 (2022): 13618.
- Cancer Vaccine Institute, University of Washington, 850 Republican Street, Brotman Bld., 2nd Floor, Box 358050, Seattle, WA 98195-8050, USA.
- Janssen Research and Development LLC, Spring House, PA, USA.
- Janssen Vaccines and Prevention, Leiden, The Netherlands.
The peptides were constructed and purified by high-performance liquid chromatography (> 90% pure; CPC Scientific).
Zonari, A., Brace, L.E., Alencar-Silva, T., Porto, W.F., Foyt, D., Guiang, M., Cruz, E.A.O., Franco, O.L., Oliveira, C.R., Boroni, M. and Carvalho, J.L. Toxicology Reports 9 (2022): 1632-1638.
Peptide 14 (ETAKHWLKGI) (Sup. Fig. 1) was purchased from CPC Scientific Inc. (USA), which synthesized the peptide by solid phase (Fmoc) on a Rink amide resin, with > 95% purity, in the form of acetate salt.
CPC Scientific Inc., a leading global peptide CRDMO (Contract Research, Development, and Manufacturing Organization) has invested in a new peptide API (Active Pharmaceutical Ingredient) manufacturing site, bringing many new jobs to Rocklin, California. The 41,000 sq ft facility located at 3880 Atherton Rd, Rocklin, CA 95765 will be utilized to manufacture clinical to commercial grade peptide products for increased manufacturing capacity and will diversify CPC Scientific’s supply chain.
CPC Scientific is entering an exciting period of growth and innovation for peptide and oligonucleotide therapeutic development and manufacturing, and we will continue to provide therapeutic APIs to pharmaceutical and biotech companies around the world. We are very pleased to partner with the City of Rocklin, California to bring manufacturing and Life-Science jobs to local American workers,” said Shawn Lee, PhD, CEO.
Ikeda, Z., Kakegawa, K., Kikuchi, F., Itono, S., Oki, H., Yashiro, H., Hiyoshi, H., Tsuchimori, K., Hamagami, K., Watanabe, M. and Sasaki, M. Journal of Medicinal Chemistry 65, no. 12 (2022): 8456-8477.
- Research, Takeda Pharmaceutical Company Limited, 26-1, Muraokahigashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
Subsequently, 5FAM–Abu–Gly–Asp–Asp–Asp–Lys–Ile–Val–Gly–Gly–Lys(CPQ2)–Lys–Lys–NH2 (purity: 97.2%, CPC Scientific, Inc.) was diluted with an assay buffer to prepare a 2.1 μM substrate solution.
The transferred energy from a fluorescent donor is converted into molecular vibrations if the acceptor is a non-fluorescent dye (quencher). When the FRET is terminated (by separating donor and acceptor), an increase of donor fluorescence can be detected. The design and synthesis work at CPC for FRET and TR-FRET peptide substrates include modification of sequences, selection of donor/quencher pairs, improvement of FRET substrate solubility and quenching efficiency.