Studies in the past quarter of century have established a role for lymphocytes in the pathogenesis of immune-mediated glomerular diseases. CD4- expressing T helper cells are a subgroup of T lymphocytes that provide help for immunoglobulin production and direct cellular immune mechanisms through activation of effector cells, such as macrophages. The role of T helper cells is variable depending on the nature of disease, and differential activation of T helper cell subsets has been proposed as one of the plausible explanations for the diversity of injury in glomerular diseases
