11

Role of Antibodies to Collagen

Type I and II

Hilde de Roosterand Eithne Comerford

Introduction

One of the major limitations in many inves-
tigations on the etiopathogenesis of cruciate
rupture (CR) in dogs is that most studies have
focused on the affected stifle joint after rupture;
the end-stage of the condition. Only a few
studies have been carried out on humoral and
cellular immunopathological mechanisms in
predisposed dogs before clinical rupture of the
contralateral cranial cruciate ligament (CrCL)
(de Bruinet al. 2007a,b).

Antigenicity of collagen

The CrCL has a microstructure of collagen bun-
dles of multiple types, but mostly type I. The
menisci are also mainly composed of collagen
type I, whereas the articular cartilage is mainly
composed of collagen type II (van Sickleet al.
1993).
The cruciate ligaments are covered by a fold
of synovial membrane and, although they have
an intra-articular position, they are extrasyn-
ovial (Alm & Stromberg 1974; Arnoczky ̈ et al.
1979). Scanning electron microscopy stud-
ies ascertained the presence of many small
holes in the enveloping membrane, allowing

infiltration of the cruciate ligaments by synovial

fluid (Kobayashiet al. 2006). Local inflamma-

tory processes and/or trauma may result in the

exposure of macromolecules, such as collagen,

that trigger immune-mediated inflammatory

responses (Figure 11.1). Once autoantibod-

ies have been produced, newly released

collagen type I can enhance joint inflammation

by forming immune complexes with these anti-

bodies resulting in activation of complement

and phagocytes (Bariet al. 1989; Carteret al.

1999).

Prevalence of antibodies to collagen

types I and II

Anti-collagen type I and II antibodies have been

detected in dogs affected with CR (Niebauer

& Menzel 1982; Niebaueret al. 1987; Bariet al.

1989; de Roosteret al. 2000). Antibodies are

present in both sera and synovial fluid aspi-

rated from the affected stifle joint, with a higher

incidence in the synovial fluid (Niebauer &

Menzel 1982; Niebaueret al. 1987; Bariet al.

1989), thus indicating local antibody produc-

tion. This finding is supported by histologi-

cal studies on synovial tissue from stifle joints

of dogs with CR (Tirgari 1977; Galloway &

Advances in the Canine Cranial Cruciate Ligament, Second Edition. Edited by Peter Muir. © 2018 ACVS Foundation.
This Work is a co-publication between the American College of Veterinary Surgeons Foundation and Wiley-Blackwell.

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