Lymphocyte T helpers (Th) play a key role in cell mediated Immune response
both as regulators and effector cells. The activation of Th cells and regul
ation of their activity are under the control of the mononuclear phagocytes
system (MPS). The basic markers of T cell and MPS activation are changes i
n the expression and affinity of their membrane receptors and the serum lev
el of secreted cytokines. Pteridins as biochemical markers immune system ac
tivation - mainly the markers of early activation and development of cell m
ediated immune response - are used in the diagnostics of allograft rejectio
n, viral, bacterial and parasitic infections, autoimmune diseases and tumor
s. In clinical laboratory examinations, the simultaneous determination of a
cute phase proteins and pteridins is often used for the evaluation of patho
logical disturbances. It can be assumed that determining these parameters i
n veterinary medicine will facilitate monitoring and prognosis of the cours
e of diseases and assessment of the value of the implemented therapeutic me
thods.