We report measurements on the aggregation processes in a colloidal suspension of polystyrene particles covered with F(ab')(2) (immunoglobulin IgG fragment) in the presence of CRP antigen (C-reactive protein) performed by static and dynamic light scattering. To study the cluster morphology of aggregates, the fractal dimension is obtained from the dependence of the scattered intensity on the scattering wavenumber. The fractal dimension values so determined were higher than those predicted by irreversible aggregation simulation models and then closer to those obtained by reversible clustering models.