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PubMed1978

[Immune profile in melanoma patients. I. PHA--stimulation of circulating lymphocytes and number of T- and B-lymphocytes (author's transl)].

20 patients with malignant melanoma in clinical stage I and II and 10 controls were examined by means of the PHA-lymphocyte-stimulation-test as by the sheep red cell rosette formation for T-cells and by the mouse red cell rosette formation for B-cells at the beginning of a non-specific immunotherapy with BCG. Mean values of both the PHA stimulation indices and the circulating T-cells and B-cells did not show any significant differences in patients with malignant melanoma compared to the control group. The relatively wide range of values was striking, especially in patients with malignant melanoma in clinical stage II. Thus cross-section studies concerning the immunology of patients with malignant melanoma are thought to be less evident for the clinician than immunologic studies of the course of disease in the individual patient.

B-Lymphocytes↗
PubMed1977

II. Mechanism of increased colony formation of CFU-S and CFU-C after in vivo PHA administration in mice.

In vivo administration of 3 mg PHA-M results in an increase in spleen colonies due to an augmented seeding of CFU-S into the spleen. An increase in the number of CFU-S in the developing nine-day spleen colonies also occurred together with a slight increase in the number of CFU-S in DNA-S phase 24 hours after PHA-M administration. The increased colony formation was due to an increased number of CFU-C from the early culture period onwards but could not be explained by an increase in the number of CFU-C in DNA/S phase. The release of colony-stimulating substances was proved but this only partially accounted for the observed rise in bone marrow CFU-C.

Animals↗
PubMed1979

PHA-induced soluble factor(s) can activate B-cells from patients with chronic lymphatic leukaemia.

Blood lymphocytes from eight patients with chronic lymphatic leukaemia (CLL) were stimulated by phytohaemagglutinin (PHA). The effect was defined as a pronounced increase of 3H-thymidine incorporation, and a concomitant blast transformation of a large portion of surface Ig-positive, E-rosette-forming (E-RFC) negative cells. E-RFC depletion reduced these effects to nearly background levels, and the pooled data strongly suggest that malignant B-lymphocytes in CLL are capable of responding to a PHA-induced T cell factor. A possible use for this factor in characterizing different subpopulations of CLL cells is discussed.

B-Lymphocytes↗
PubMed1977

Changes in peripheral blood lymphocyte nucleoli in a follow-up of renal allograft recipients. Correlation with the response to PHA.

Changes in the morphology of nucleoli in peripheral blood lymphocytes and the reactivity to PHA were used in the immunological follow-up of renal allograft recipients. The increased numbers of "active" lymphocytes containing compact nucleoli or nucleoli with nucleolonemas, characteristic for cells actively synthesizing RNA, preceded 21 out of 28 rejection episodes. The results of the nucleolar test mathematically correlated with the results of the test of lymphocyte transformation to PHA. The described testing of lymphocyte activation according to the morphology of the nucleoli may serve as a rapid and economical method for the prediction of impending allograft rejection crises in the clinic.

Azathioprine↗
PubMedDate not supplied

PHA dose dependent defect in lymphocyte stimulation and E-rosette-forming cells in untreated Hodgkin's disease.

14 untreated patients with Hodgkin's disease were tested for lymphocte reactivity in vitro to optimal and suboptimal doses of PHA. A PHA dose-dependent defect in lymphocyte stimulation was demonstrated in patients when compared with a group of normal individuals. No correlation between the in vitro defect and decreased absolute number of E-rosette-forming cells (T-lymphocytes) in peripheral blood was found.

Adolescent↗
PubMed1986

Response to ConA and PHA of host and donor thymic cells in radiation bone marrow chimeras.

The response of thymic cells to ConA and PHA was followed during 49 days in 9 Gy-irradiated C3H mice reconstituted with (C3H X AKR)F1 BM. Thymic suspension were fractionated firstly according to their capacity to bind PNA, and secondly by their Thy-1 surface antigen: Thy-1.1 antiserum was used either to lyse doner-derived cells or to separate them from host cells by panning. From days 14 to 25, when the donor-derived elements expand rapidly, the PNA- fraction remains stable and equal to 6%, suggesting that PNA+ and PNA- cell populations develop independently of each other. On the contrary, the PNA- fraction which initially represents 6% of the surviving cells rises up to 12% after day 20 and remains at this level in the long-lived host population until the end of the experiment (49 days). The response to ConA returns to normal as early as 15 days after X-rays in the PNA- fraction, whereas the response to PHA is still impaired at the end of the experiment. In both cases host cells express a higher level of responsiveness to mitogens than donor cells.

Agglutination↗
PubMed1987

[Lymphocyte subsets and response of breast cancer and benign mammary disease to PHA].

The lymphocyte counts, subsets and response to PHA in the peripheral blood of patients with breast cancer (stage I-III) and with a benign mammary disease have been evaluated. In the breast cancer cases, the lymphocyte counts and stimulation index of PHA increased gradually as the stages advanced but there was no statistical significance. The ratio and number of OKT 4 positive lymphocytes were significantly lower in patients with breast cancer (stage I) between 40 and 59 years old than in patients with benign mammary diseases between the same ages. This impairment of OKT 4 in breast cancer (stage I) cases was considered as either a cause of the carcinoma or as a reflection of the environment of steroid hormones.

Antigens, Surface↗
PubMed1985

[The effect of cefaclor, doxycycline and other oral antibiotics on phagocytosis of polymorphonuclear granulocytes and PHA-induced stimulation of blood lymphocytes in man].

The influence of the orally applicable antibacterial agents, cefaclor (Panoral), doxycycline, erythromycin, and cotrimoxazole on phagocytosis by human neutrophil granulocytes was investigated. Further, the influence of cefaclor, erythromycin, and doxycycline on PHA stimulation of human blood lymphocytes was studied. Doxycycline (1 mg/ml) had strongly suppressive effects on phagocytosis, whereas cefaclor (1 mg/ml cotrimoxazole (0.1 mg/ml), and erythromycin (0.1 mg/ml) did not suppress phagocytosis. PHA-induced lymphocyte stimulation was strongly inhibited by doxycycline (10 micrograms/ml), whereas cefaclor (10 micrograms/ml) did not suppress at all. Erythromycin (10 micrograms/ml) exerted some inhibition (average 12.6%). These results are discussed with respect to immunoneutrality of antibacterial agents.

Anti-Bacterial Agents↗
PubMed1985

[PPD, PHA and Su-PS skin tests in genitourinary malignancies].

PPA, PHA and Su-PS skin tests were performed on 152 urogenital malignancy patients and the results obtained were analysed in terms of clinical course. The survival rate of 86 patients showing a positive response to the PPD skin test was significantly higher (P less than 0.005) than that of 65 patients showing a negative response to the PPD skin test. Among the 33 renal tumor patients, the positive rate of the 10 patients with stage I tumors to PPD skin test was significantly higher (P less than 0.05) than that of the 13 patients with stage IV tumors. In 68 bladder tumor patients, the response rate to PPD skin test in 47 patients with a low stage tumor was significantly high (P less than 0.05) compared with that in 21 patients with a high stage tumor. Out of 47 patients who died during the 84-month observation period, 10 (21.7%) and 3 (13.3%) showed a response change from negative to positive, in the PPD test and Su-PS test, respectively. It was assumed that 32 of the 46 patients (69.6%), 4 of the 6 patients (66.7%) and 17 of the 23 patients (73.9%) submitted to the PPD, PHA and Su-PS tests, respectively, showed a negative response at the time of their death.

Carcinoma, Renal Cell↗
PubMed1985

Amiloride inhibits the PHA-evoked mouse splenic lymphocyte proliferation.

The present study was aimed to ascertain whether Na+ influx can be involved in regulation of blastogenesis and proliferation of PHA stimulated mouse splenic lymphocytes. The cells were cultivated in the presence of different concentrations of amiloride, an inhibitor of passive Na+ influx, and cellular activation was monitored by 3H-thymidine incorporation and blast index determination. The drug was not toxic and inhibited cell growth in concentrations ranging from 1 X 10(-3) to 1 X 10(-5) mmol/ml. The results are in agreement with the hypothesis that Na influx is necessary for PHA evoked mouse splenic lymphocyte activation.

Amiloride↗
PubMedDate not supplied

[Degradation of DNA and chromatin in cells of mouse lymphoid organs after irradiation and PHA administration].

Phytohemagglutinin (PHA) administered to irradiated mice did not influence the postirradiation degradation of DNA and the yield of polydeoxynucleotides (PDN) in cells of thymus, spleen and bone marrow. The degree of degradation of DNA and chromatin was higher in the thymus as compared to other studied organs. A possible mechanism of the radiotherapeutic action of PHA is discussed.

Animals↗
PubMed1979

Effect of levamisole on interferon production by PHA-stimulated human leukocyte cultures.

Mononuclear leukocytes of 10 normal blood donors were cultured in vitro and treated with phytohemagglutinin (PHA-P) and/or levamisole. Interferon-like activity was investigated in the supernatant fluids of the cultures, using VSV as challenge virus. In most of the cases the PHA-stimulated interferon-like activity was slightly but significantly enhanced by levamisole. The antiviral activity produced in the supernatant fluids was characterized as interferon since it was trypsin sensitive, species specific and inhibited by specific antiserum. This interferon has the characteristic sensitivity to PH2 of immune interferon.

Cells, Cultured↗
PubMed1984

Nucleolar silver-staining patterns related to cell cycle phase and cell generation of PHA-stimulated human lymphocytes.

Silver staining (Ag-I) was used to investigate changes in the nucleolar structure of PHA-stimulated human lymphocytes through the phases of the cell cycle, G1, S and G2. Ag-I patterns and cell cycle phases of individual cells were assessed by sequential silver staining, Feulgen staining, DNA microdensitometry and 3H-thymidine autoradiography. The morphology and number of Ag-I nucleoli in a particular cell depended upon the phase of the cell cycle reached and on the number of generations the cell had passed through in culture. Resting, unstimulated cells usually had one small silver positive nucleolus. During blast transformation, the silver stained nucleoli increased in number and size, and then fused to form one very large, rounded or irregular-shaped nucleolus which was present through all cell cycle phases of the first reproductive cycle. Many lymphocytes developed a band-shaped nucleolus during their first S phase in culture. Lymphocytes at all cell cycle stages of the second and third generations after PHA-stimulation had multiple nucleoli whose combined areas approximated that of the single large nucleolus observed in first generation cells.

Cell Cycle↗
PubMed1983

PHA-induced neutrophil-mediated cytotoxicity.

Neutrophils activated by phytohemagglutinin (PHA) were cytotoxic to chicken red blood cells (CRBC), as determined by the 51Cr release assay. High levels of cytotoxicity were obtained when one CRBC was available for each effector cell. Neutrophils from patients with Chronic Granulomatous Disease (CGD), incapable of generating potentially toxic oxygen radicals, had a reduced cytotoxicity activity, suggesting the requirement for an intact oxidative metabolism in the PHA-induced neutrophil-mediated cytotoxicity. However, CGD neutrophils maintained approximately 50% of this activity, compared with normal cells. These findings support the conclusion that both oxygen-dependent and oxygen-independent mechanisms are necessary to achieve an efficient cytotoxicity.

Adolescent↗
PubMed1983

[Studies on the effect of lentinan on human immune system. II. In vivo effect on NK activity, MLR induced killer activity and PHA induced blastic response of lymphocytes in cancer patients].

Immunological activities of lymphocytes were studied in patients with cancer of digestive organs and mamma after administration of lentinan. When 11 cancer patients received lentinan i.v. 2 mg, NK activity of lymphocytes was increased in 4 patients on the following day. With the same condition, MLR induced killer activity against Raji cell of lymphocytes was increased in 3/7 patients and PHA response was also increased in 3/7 patients. These activities were returned to values before the administration of lentinan. Then each activity was examined after administration of lentinan twice a week. NK activity, MLR induced killer activity and PHA response were increased in 4/15, 8/12 and 5/11 patients, respectively.

Cytotoxicity, Immunologic↗
PubMed1984

[A comparative study to detect the HBsAg by the ELISA, RIA and PHA technics in patients with viral hepatitis].

The presence of HBsAg in the serum samples of patients with Acute Viral Hepatitis was detected by various methods, such as ELISA, RIA and PHA in order to determine the most sensitive technic. According to our results ELISA was found to be the most sensitive commercially available test for HBsAg. Among 92 patients with presumptive viral hepatitis HBsAg was detected in 36, 32 and 16 of them by ELISA, RIA and PHA tests respectively.

Enzyme-Linked Immunosorbent Assay↗
PubMed1980

Effect of low molecular factors released during allogeneic interactions of leucocytes or brain cells on PHA- and LPS-induced DNA synthesis in lymphocytes.

Male (A/Ph and C3H/Cbi/BOM) mice were used in our experiments. The cell-free supernatants of spleen mixed leucocyte cultures and allogeneic brain cortex cells were collected upon short-term incubation and tested in a comparative study. Spleen and brain low molecular factors were fractionated (ultrafiltration and gel column chromatography) and assayed for their activity in mitogen-induced 3H-thymidine incorporation into spleen lymphocytes. The specific release of the allogeneic spleen fraction (ASF-2) has been observed. A non-specific stimulating effect of ASF-2 on PHA- and LPS-activated spleen lymphocytes was shown. In contrast, a non-specific suppressive effect of brain fraction on PHA- and LPS-stimulated lymphocytes was demonstrated. The opposite effects of spleen and brain factors can be connected with their different composition. The lymphocyte cultures were not affected by spleen or brain factor, when cultured without the addition of mitogen. Positive and negative regulation or modulation of triggering events in lymphocyte activation by these factors can be suggested.

Animals↗
PubMed1981

On the influence of hydrocortisone on the stimulation of mouse spleen cells by PHA. Evidence for the involvement of suppressor cells.

The stimulation rate with PHA of murine spleen cells increases after removal of glass-adherent cells from the total spleen population. Unfractionated spleen population from HC treated mice suppresses the response to PHA of glass non-adherent cells from untreated animals only 24-48 h after HC treatment. From the third day on after the treatment the suppressive effect disappears.

Animals↗