The proportion of peripheral blood mononuclear cells expressing the T helper cell phenotype and levels of antiendotoxin core antibody, interleukin (IL) 6 and C-reactive protein (CRP) were determined within 48 h of admission in a group of 29 patients with acute pancreatitis (16 mild, 13 severe attacks). There was a significant decrease in the proportion of T helper cells (12.2 versus 34.9 per cent, P < 0.01) and significant increases in levels of IL-6 (69.5 versus < 10 pg/ml, P < 0.01) and CRP (119 versus 30.5 mg/l, P < 0.01) in severe compared with mild attacks. During the convalescent stage at 3 months after admission, severe attacks were characterized by a significant increase in the proportion of T helper cells compared with the acute period (22.4 versus 10.6 per cent, P < 0.01). A persistently low proportion of T helper cells was associated with residual pancreatic necrosis. The presence of circulating endotoxin was demonstrated in two mild and two severe attacks using the Limulus amoebocyte lysate assay, and abnormal levels of antiendotoxin core antibodies were found in 70 and 92 per cent of mild and severe attacks respectively. There was a strong inverse correlation between levels of CRP and the proportion of T helper cells in severe disease (r = -0.76, P = 0.004). Translocation of endotoxin from the gastrointestinal tract may partly explain the abnormal levels of T helper cells, IL-6 and CRP.

Forty-six gallbladders were examined for the number, weight, size and shape of their gallstones, and for the volume of flow, under conditions of constant pressure, that was transmitted by the cystic duct. Eighteen gallbladders were from patients who had previously suffered an attack of acute pancreatitis, and the other 28 were from control patients who had not had a known attack of pancreatitis. Cystic duct flow rates, which we assumed were related to cystic duct calibre, were greater in the pancreatitis group (mean = 282 ml/min) than in the controls (mean = 134 ml/min) (P less than 0.01). There were more stones in the gallbladders of the pancreatitis patients, and the mean stone weight was lower in this group (0.31 g compared with 0.74 g; P less than 0.02). Large stones were more frequently seen in the control gallbladders. Small, irregular or mulberry-shaped stones were the dominant stone type in 78 per cent of the pancreatitis group but in only 43 per cent of the controls (P less than 0.05). Thus a large-calibre cystic duct and numerous small stones with an irregular shape appeared to be more common in patients who had suffered acute pancreatitis, and may be factors in the pathogenesis of the attack.

Analysing the regeneration of T lymphocytes after high-dose chemotherapy with autologous peripheral blood progenitor cell rescue (PBPCR) may help elucidate the mechanisms of immune recovery. The T-cell receptor variable beta chain (TCRBV) repertoire of adult patients undergoing high-dose chemotherapy was analysed by flow cytometry, before and after treatment. Four patients were found to have a stable expansion present (TCRBV3, 17, 21 and 22) ranging from 8% to 42% of the CD4(+) or CD8(+) repertoire. We demonstrated that, in these patients, following high-dose chemotherapy and autologous stem cell transplantation, the clonal expansions reappeared in peripheral blood and returned to pretransplant levels. Three expansions (CD3(+)CD8(+)TCRBV3(+), CD3(+)CD4(+)TCRBV21(+) and CD3(+)CD8(+)TCRBV22(+)) were further defined by sequence analysis of the complementarity-determining region (CDR)3 portion within the TCR rearrangements. These were shown to be predominantly clonal, with the same sequences being identified in peripheral blood before and after PBPCR, providing evidence that the overwhelming majority of T cells in these expansions arise from mature lymphocytes. This study demonstrated that patients undergoing autologous PBPCR for high-dose chemotherapy regenerate clonal expansions, consistent with pretreatment levels. They also regenerate T-cell repertoires with each TCRBV family represented to a similar level as that prior to high-dose chemotherapy.

Summary. Analysing the regeneration of T lymphocytes after high-dose chemotherapy with autologous peripheral blood progenitor cell rescue (PBPCR) may help elucidate the mechanisms of immune recovery. The T-cell receptor variable beta chain (TCRBV) repertoire of adult patients undergoing high-dose chemotherapy was analysed by flow cytometry, before and after treatment. Four patients were found to have a stable expansion present (TCRBV3, 17, 21 and 22) ranging from 8% to 42% of the CD4 1 or CD8 1 repertoire. We demonstrated that, in these patients, following high-dose chemotherapy and autologous stem cell transplantation, the clonal expansions reappeared in peripheral blood and returned to pretransplant levels. Three expansions (CD3) were further defined by sequence analysis of the complementarity-determining region (CDR)3 portion within the TCR rearrangements. These were shown to be predominantly clonal, with the same sequences being identified in peripheral blood before and after PBPCR, providing evidence that the overwhelming majority of T cells in these expansions arise from mature lymphocytes. This study demonstrated that patients undergoing autologous PBPCR for high-dose chemotherapy regenerate clonal expansions, consistent with pretreatment levels. They also regenerate T-cell repertoires with each TCRBV family represented to a similar level as that prior to highdose chemotherapy.

No abstract