Cytotoxic T-lymphocyte response to autologous human squamous cell cancer of the lung: epitope reconstitution with peptides extracted from HLA-Aw68.

Cytotoxic T-lymphocytes (CTLs) specific for autologous human squamous cell cancer of the lung were generated by stimulation of peripheral blood lymphocytes with autologous tumor cells in vitro. The CTL line was >97% CD3+, CD8+, CD16- and produced tumor necrosis factor-alpha, gamma-interferon, and granulocyte-macrophage colony-stimulating factor after stimulation with autologous tumor. The CTLs lysed autologous tumor but failed to recognize autologous or histocompatibility leukocyte antigen-matched lymphoid cells, K562, or allogeneic tumor cells of several histological types. Antibody-blocking studies suggested that the CTLs recognized one or more antigens presented by the class I major histocompatibility complex molecule Aw68. To characterize these antigens further, histocompatibility leukocyte antigen Aw68 molecules were extracted from the squamous cell cancer of the lung tumor line by immunoaffinity chromatography, and the associated peptides were eluted in acid and separated by reversed-phase high-performance liquid chromatography. Reconstitution of the CTL epitope was evaluated by adding these peptides to autologous Epstein-Barr virus-transformed B-cells. Two peaks of reconstituting activity were observed, suggesting that these CTLs recognize at least two Aw68-associated peptides. This study confirms the existence of a CTL response against autologous human squamous cell cancer of the lung and suggests that this CTL response is directed against peptide epitopes presented by the class I major histocompatibility complex molecules. It is anticipated that this approach will permit identification of peptide epitopes for lung cancer-specific CTLs.

Delayed developmental sequences in rodent diabetic embryopathy.

Diabetes induced by alloxan at day 6 of gestation in Wistar rats produced decreased fetal growth, delayed skeletal ossification, decreased fetal kidney beta-glucuronidase, and an increased frequency of fetal birth defects which correlated with the degree of diabetic control. Offspring of severely diabetic mothers (mean blood glucose greater than 501 mg/dl) sacrificed at 20 days had a mean weight of 2.12 +/- 0.16 g, a mean of 1.8 +/- 0.46 caudal ossification centers, and a 28% incidence of birth defects as compared to 3.70 +/- 0.22 g, 5.9 +/- 0.42 caudal centers, and 1.1% defects for controls. Offspring of severely diabetic mothers sacrificed at 21 days had mean numbers of caudal and sternal ossification centers which did not significantly differ from controls, indicating that decreased ossification observed at 20 days of gestation is a delayed developmental sequence which is mostly corrected by 21 days. Offspring of moderately diabetic (mean blood glucose 300-500 mg/dl) and insulin-treated dams (mean blood glucose 152-168 mg/dl) had intermediate degrees of growth or ossification delay and birth defect frequency at both the 20- and 21-day sacrifices. Maternal diabetes also retards the developmental increase in fetal kidney beta-glucuronidase such than 20-day offspring of severely diabetic mothers had a mean specific activity of 1.1 nmol/min/mg compared to 3.0 nmol/min/mg for controls. The results support prior studies in rodents suggesting a progression of early growth delay, altered developmental sequences, and birth defects in diabetic pregnancy. This progression is suggested as a common teratogenic mechanism which has implications for evaluating analogous pregnancies in man.