Marked gamma delta T-cell decrease in peripheral blood of patients with primary biliary cirrhosis (PBC)

PBC is a cholestatic liver disease of unknown etiology with autoimmune features that is often associated with other autoimmune diseases. We analyzed peripheral blood T-cell subsets in patients groups with PBC (n = 11), non-PBC hepatobiliary disease (n = 11) and an age and sex matched control group (n = 11) by two color FACS-analysis. Seven out of eleven PBC patients exhibited markedly lowered and nearly undetectable levels of gamma delta T-cells (< 0.8%). None of the individuals in the non-PBC hepatobiliary disease (HBD) group or the normal control group had gamma delta values below 1%. The other four individuals in the PBC group had gamma delta values within the normal range. Overall, the PBC group had a statistically significant, lowered mean percentage of gamma delta T-cells (1.50%) as compared to the hepatobiliary disease group (3.76%) and the control group (4.22%, p = 0.01). The percentages of CD4+ and CD8+ and alpha beta TCR+ CD4-CD8- double negative cells in PBC patients did not differ from the control group. PBC patients with normal gamma delta cell counts did not differ from the PBC group with low gamma delta values in autoantibody titers, liver tests or treatment of the disease. As a possible cause for the observed decrease of gamma delta T-cells three sera of PBC patients with low gamma delta T-cell counts were screened by single color, indirect immunofluorescence for antibodies to gamma delta T-cell enriched lymphocytes, but no differences to control sera were observed.(ABSTRACT TRUNCATED AT 250 WORDS)