Correlation between serum alpha-globulin and plasma inhibitory effect on PHA-stimulated lymphocytes in colon cancer patients

Serum immunomodulatory factors in gastrointestinal diseases. A 30-50-kD serum fraction in Crohn's disease capable of modulating lymphocyte activation

We tested the hypothesis that serum factors present in Crohn's disease interfere with the process of lymphocyte activation. The mitogen-induced proliferation and the expression of early activation antigens by normal lymphocytes cultured in the presence of either Crohn's disease sera or sera from different controls were evaluated. The mitogen-induced proliferation was significantly impaired in the presence of Crohn's disease sera. These sera markedly inhibited the mitogen-induced interleukin-2 receptor (IL-2R) expression (48% inhibition), while the effect of sera on the expression of the transferrin receptor and the 4F2 antigen was much less pronounced. Diafiltration experiments showed that the inhibitory effect was confined to a 30-50-kD serum fraction. Such a serum property was not related to the patients' disease activity and disappeared after surgical removal of the affected bowel. The capability of inhibiting the mitogen-induced IL-2R expression was not restricted to Crohn's disease and was observed with sera from other inflammatory and neoplastic gastrointestinal disorders. This study indicates that a marked inhibition of the IL-2R is a mechanism underlying the immunosuppressive property of the serum in Crohn's disease and in other gastrointestinal conditions.

Reversal of defective lymphoproliferation in postoperative patients with colon cancer

To establish a method for evaluation of immunological parameters in small blood samples, a whole blood technique was developed for the estimation of mitogen- or antigen-induced proliferation. Studies regarding cellular immunity in patients with colon cancer were done with 108 patients in all tumor stages, aged 32 to 80 years. They were studied before surgery and 10 days after operation. A group of 35 patients were further tested 3 months after surgical treatment. In patients with colon cancer the proliferative responses of peripheral blood lymphocytes to mitogens were significantly lower in comparison to healthy controls. These results were found when the response to concanavalin A, phytohemagglutinin, OKT 3, and pokeweed mitogen were analyzed preoperatively and 10 days postoperatively. There was no relation to the stage of disease. The marked reduction of mitogen responses was followed by a gradual return toward normal values 3 months after surgical resection of neoplastic growth in 80% of the patients. Our studies indicate that the defects were largely restored when testing was performed 3 months after operation. Using this result, it will be possible to perform long-term studies in order to establish if there is a correlation between the return to normal immune reactivity and the survival of individual patients.

Hypothesis: blocking factors and human pregnancy: an alternative explanation for the success of lymphocyte transfusion therapy in abortion-prone women

Recent evidence has demonstrated that the non-specific immunosuppression that develops during pregnancy is not due to the de novo synthesis of immunosuppressive factors (ISF) but is a result of the activation of pre-existing molecules. The latter are present in normal sera as inactive complexes with a molecule which is specifically depleted following conception resulting in the activation of the ISF; the depleted molecule is termed the pregnancy-depleted immunoregulatory factor (pdIRF). Since non-specific ISF are detected in various diseases, it is proposed that the ISF-pdIRF relationship observed in pregnancy is a universal phenomenon and that the depletion of pdIRF and the activation of ISF can be achieved by a variety of stimuli. It is further proposed that abortion-prone women fail to adequately deplete their pdIRF levels so that the ISF are not activated. However, owing to the universal nature of the system, lymphocyte transfusion therapy supplies the necessary stimuli so that the pdIRF levels are depleted and the ISF activated which ensures a successful outcome to the pregnancy.

Pregnancy-associated nonspecific immunosuppression: kinetics of the generation and identification of the active factors

The effect of gestational age and maternal parity on the development of nonspecific immunosuppressive activity in the sera of pregnant women, which inhibited the in vitro transformation of unrelated lymphocytes by phytohemagglutinin, was examined. Quantitative demonstration of this activity was dependent, in part, on the source of the lymphocytes and on the serum concentration in culture. The immunosuppressive activity became evident as the pregnancy progressed, and in late-pregnancy sera it was mediated by two factors, immunosuppressive factors (ISF) I and II with apparent Mr of 2 X 10(6) and 150,000 daltons. By analysis and comparison of different types of sera fractionated by gel filtration on Sephacryl S-300, it was evident that ISF-I and ISF-II were also present in male and nulliparous nonpregnant female sera, but in inactive forms. Hence the immunosuppressive factors did not appear to be "produced" in pregnancy, but the observed activity was a reflection of the "activation" of preexisting molecules in the serum. An accompanying report (Am J Reprod Immunol Microbiol. 1985; 9:84-90) describes the regulation of the activation event.

Immunosuppressive factor from the spleen in gastric cancer patients

The spleens of gastric cancer patients were examined to determine whether this organ releases an immunosuppressive factor. Compared to serum from peripheral blood, serum from splenic venous blood of advanced gastric cancer patients had greater suppressive activity to normal lymphocyte responses to phytohemagglutinin (PHA); it also contained significantly more immune complexes. Furthermore, the supernatant from spleen cell cultures from advanced gastric cancer patients significantly suppressed normal lymphocyte responses to PHA. This immunosuppressive activity was enhanced when the supernatant was from cultures of separated nonadherent subpopulations. These observations were not detected in patients with early gastric cancer. The blastogenic response to PHA and the percentage of T-cells among spleen cells was not affected by the cancer stage. These results suggest that the spleen of patients with advanced gastric cancer participates in the induction of serum immunosuppressive factors, possibly due to a change in splenic lymphocyte subsets.

Monocyte and lymphocyte interaction in patients with advanced cancer. Evidence for deficient IL-1 production

Patients with advanced neoplasms have a variety of immunologic abnormalities, including the impaired responsiveness of peripheral blood lymphocytes to mitogen and alloantigen. In the current study it was observed that cancer patients have increased monocyte suppressor cell activity that is mediated by prostaglandins and contributes to the depressed proliferative response of the patients' T-cells. This monocyte suppression, however, is not the major cause of the depressed proliferative response. The study also demonstrated that levels of interleukin 1 (IL-1) produced by lypopolysacharide-activated monocytes from cancer patients are significantly lower than they are in normal subjects.

Immunosuppressive acidic protein (IAP) in gastric cancer patients

Immunosuppressive acidic protein (IAP) in the serum from peripheral, splenic and regional venous blood of gastric cancer patients was assayed. Peripheral venous blood was collected before, and for several months after the surgery. The IAP values of peripheral venous blood, increased with advancing cancer stage; in patients at the same cancer stage, the IAP values of venous blood draining from the cancer lesion were the highest. In curatively operated patients, the IAP values increased during the first postoperative month and decreased thereafter. In patients with non-resectable cancer and in patients subjected to palliative surgery, these values remained high; they increased sharply just before death. Determination of the serum IAP values in gastric cancer patients may be useful in estimating the immunological state of gastric cancer patients and for monitoring the postoperative immunological status.

Depressed in vitro peripheral blood lymphocyte response to mitogens in cancer patients: the role of suppressor cells

The reactivity of peripheral blood lymphocytes from patients with advanced malignancy was assessed by mitogen-induced stimulation of protein synthesis as measured by 3H-leucine incorporation. It was confirmed that the lymphocyte response of patients was depressed. Furthermore, the lymphocytes of 15 out of 27 cancer patients, selected because of their low responses, inhibited the reactivity of normal lymphocytes in co-cultures. The lymphocytes from one patient with Hodgkin's disease were also inhibitory. In contrast, lymphocytes from healthy subjects, patients with chronic lymphocytic leukaemia, lymphosarcoma or multiple myeloma caused no suppression. Experiments with purified cell populations from patients with carcinoma indicated that purified T cells responded to mitogens while unseparated lymphocytes failed to respond and that the inhibitory activity was due to adherent cells, presumably monocytes. There was no evidence for B-cell-mediated suppression. However, in two cases inhibition was caused by isolated T cells of the patients and not by adherent cells. These experiments suggested that one mechanism for the depression of cell-mediated immunity seen in patients with advanced cancer may be the nonspecific suppresssion of certain T-cell functions by circulating monocytes.

The prognostic significance of peripheral lymphocyte counts in patients with breast carcinoma

A retrospective study evaluating five-year survival rates in relation to pretreatment lymphocyte counts was undertaken in 453 patients with breast carcinoma. Patients with early tumor stages had higher pretreatment lymphocyte counts than those with advanced tumors: five-year survival in patients with pretreatment counts above 2000 per mm3 was 87% in Stage I, 67% in Stage II, and 57% in Stage III, while the comparable figures in patients with lower counts were 82%, 51%, and 29%. The differences in five-year survival rates for Stage II and III were significant: z equals 1.6955, p equals 0.046 and z equals 1.8841, p equals 0.03. Similar differences were noted in the disease-free, five-year survival rates. The corresponding figures in the three tumor stages for patients with counts above 2000/mm3 were 80%, 63%, and 53%, while those for patients with lower counts were 74%, 44%, and 18%. The differences in Stage II and III were also statistically significant: z equals 1.8430, p equals 0.33 and z equals 2.592, p equals 0.005 respectively. The possibility that the presence of suppressant factors related to the thymus may influence levels of lymphocytes was evaluated. Comparison of pre-thymectomy and postthymectomy lymphocyte counts in a control group of patients who had thymectomy for myasthenia gravis revealed a gradual increase of lymphocytes following thymectomy. The increase was significant at the second year following thymectomy. These observations indicate that lymphocyte counts may serve as prognostic indicators in patients with breast cancer. Low lymphocyte counts may be related to the presence of suppressor substances.

[Carcinofetal antigens. III. Further carcinofetal antigens (author's transl)]

The occurrance and significance of important carcinofetal antigens other than AFP and CEA are reported. These included the alpha 2 H-protein which is produced in the liver and increases in serum of patients with various tumors, the fetal sulphoglycoprotein antigen FSA from the gastric juice of patients with gastric cancer, the carcinoplacental alkaline phosphatase (REGAN-isoenzyme)which is found in the serum of patients suffering from e.g. bronchogenic, mammary, urogenital and gastrointestinal carcinomas, the beta-S-fetoprotein which is most likely to be identical with C-reactive protein, gamma-fetoprotein, the carcinofetal antigen in glial tumors (CFGA); ectopic production of placental hormones like human gonadotropin, placental lactogen, plasminogen-activators; leukemia-associated antigens. Furthermore, some other less known carcinofetal antigens are mentioned.

Depressed cell-mediated immunity in patients with primary intracranial tumors. Characterization of a humoral immunosuppressive factor

Tumor immunity in patients with primary intracranial tumors was assessed in relation to the general status of host immunocompetence. Lymphocyte sensitization to tumor-specific membrane antigens was demonstrated by the proliferative response of lymphocytes in the presence of autochthonous tumor cells. Paradoxically, one-half of the patients could not be sensitized to a primary antigen, dinitrochlorobenzene; existing delayed hypersensitivity was also depressed, as measured by skin tests and lymphocyte transformation in response to common antigens. A heat-stable factor in patients' sera blocked cell-mediated tumor immunity. In addition, these "enhancing" sera consistently suppressed the blastogenic response of autologous and homologous lymphocytes to phytohemagglutinin and to membrane antigens on allogeneic cells in the one-way mixed lymphocyte culture. When patients' leukocytes were washed and autologous plasma replaced with normal plasma, reactivity in the mixed lymphocyte culture increased to normal values. In vitro immunosuppressive activity in patients' plasma or sera correlated with depressed delayed hypersensitivity. After removal of the tumor, suppressor activity disappeared. IgG fractions of patient sera contained strong immunosuppressive activity. These data suggest that the suppressor factor may be an isoantibody elicited by the tumor that also binds to receptors on the lymphocyte membrane. In addition to specifically blocking cell-mediated tumor immunity, enhancing sera may broadly depress host immunocompetence.