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Mucosal immune responses to microbes in genital tract
Published in Phillip D. Smith, Richard S. Blumberg, Thomas T. MacDonald, Principles of Mucosal Immunology, 2020
Carcinoembryonic antigen-related cell adhesion molecule 3 (CEACAM3) mediates the opsonin-independent recognition and elimination of a restricted set of human-specific gram-negative bacterial pathogens including N. gonorrhoeae. CEACAM3 binds to the Opa protein expressed by N. gonorrhoeae and internalizes the bacteria for degradation. N. gonorrhoeae expresses lipooligosaccharide, lacking the O antigen. This structure is recognized by TLR2, TLR4, and triggering receptor expressed on myeloid cells-2A (TREM-2A). In addition, porins and Lip lipoproteins of N. gonorrhoeae are recognized through TLR2.
Fusobacterium spp. target human CEACAM1 via the trimeric autotransporter adhesin CbpF
Published in Journal of Oral Microbiology, 2019
Matthew L. Brewer, David Dymock, R. Leo Brady, Bernhard B. Singer, Mumtaz Virji, Darryl J. Hill
The phenylalanine at position 29 and glutamine at position 44 on the CFG face of CEACAM1 are the only two unique residues shared between CEACAM1 and CEA, F29 is also found in CEACAM3, whilst Q44 is not found in any other CEA-family member. Altering the F29 and Q44 residues to naturally occurring alternatives found within other CEACAMs completely disrupts binding (Figure 11). Additionally, mutants from other areas on the CFG face were shown to negate adhesion, such as Y34, G47, Q89, and I91. Interestingly, Q89N displayed reduced, but higher than background, levels of adhesion to group II CbpF and no binding at all to group I. The higher binding of V96A mutant to CbpFII compared to CbpFI could implicate V96 in the CbpF binding surface on CEACAM1. However, no significant difference was observed between V96A and CC1-Fc in binding to recombinant CbpFI or CbpFII. As the IgV-like N-terminal domain of all CEACAMs is highly conserved, and that CbpFs have only been seen to bind CEACAM1 and CEA, this suggests that these proteins have specifically evolved to target these proteins while avoiding other highly similar receptors such as CEACAM3. This is contrary to UspA1 for example, which has been shown to bind to CEACAM3 and -6 as well as CEACAM1 and -5 [49,50]. This could allow CbpF to avoid activating neutrophils where CEACAM3 is exclusively located, where CEACAM3 induction can lead to a proinflammatory effect via its immunoreceptor tyrosine-based activation motif (ITAM)-like domain [49,51].
T cell-mediated elimination of cancer cells by blocking CEACAM6–CEACAM1 interaction
Published in OncoImmunology, 2022
Jessica Pinkert, Hans-Henning Boehm, Mark Trautwein, Wolf-Dietrich Doecke, Florian Wessel, Yingzi Ge, Eva Maria Gutierrez, Rafael Carretero, Christoph Freiberg, Uwe Gritzan, Merlin Luetke-Eversloh, Sven Golfier, Oliver Von Ahsen, Valentina Volpin, Antonio Sorrentino, Anchana Rathinasamy, Maria Xydia, Robert Lohmayer, Julian Sax, Ayse Nur-Menevse, Abir Hussein, Slava Stamova, Georg Beckmann, Julian Marius Glueck, Dorian Schoenfeld, Joerg Weiske, Dieter Zopf, Rienk Offringa, Bertolt Kreft, Philipp Beckhove, Joerg Willuda
Recombinant human CEACAM1, −5, −6 proteins were purchased from R&D Systems, human CEACAM3 was obtained from Sino Biological. Other recombinant human or cynomolgus CEACAM6 variants including Fc fusions and domain variants were produced as described in the Supplementary Methods.