Chemistry Reference
In-Depth Information
27.10
Conclusions
In this chapter we have described distinct interactions of lectins and carbohydrates
expressed on surfaces of host cells and pathogens. We have restricted ourselves
to some of the many structures that are involved in the complicated network and
cross-talk between the immune and vascular systems during infl ammatory reac-
tions as well as during pathogen recognition by immune cells. Although still at
an early stage, glycoimmunology has already contributed many exciting new con-
cepts to all sectors of immunology and provides explanations for mechanisms
involved in early steps of the immune response, especially those of complex adap-
tive immune responses. Carbohydrate-lectin interactions also bridge innate and
adaptive immunity, since many of the lectin reactivities fulfi ll tasks in both
systems.
Summary Box
Infl ammation is the response of the immune and the vascular system to inju-
ries caused by pathogens, damaged cells or irritating agents. Communication
of immune cells and vascular endothelial cells with infl ammatory reagents is
to a large extent mediated by carbohydrate-lectin interactions. These interac-
tions regulate adhesion processes and organ- specifi c homing of immune cells,
and also infl uence intracellular signaling. On the carbohydrate side, predomi-
nant structures comprise those of histo-blood groups or related sequences such
as Le
x
, Le
a
and Le
y
(CD15, CD173 and, CD174) carried by distinct glycoproteins.
On the lectin side, three major families are involved: selectins, siglecs and
galectins.
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