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PubMed1982

Generation of CFUC suppressor T cells in vitro. II. Effect of PHA, PWM, and Con-A on bone marrow and peripheral blood lymphocytes from healthy donors.

T lymphocytes were derived by E-rosetting techniques from the peripheral blood and bone marrow of 12 healthy donors. Following incubation of 18 h with PWM, PHA, Con-A or culture medium (RPMI) alone, the lymphocytes were harvested by centrifugation and washed. Both lymphocytes and culture supernatants were tested for CFUC suppressor activity in semisolid bone marrow cultures. The results of this study indicate that (a) T cells and supernatants from unstimulated cultures contained no CFUC suppressor activity, (b) T cells and supernatants from cultures stimulated with PHA, PWM or Con-A significantly suppressed autologous and allogeneic bone marrow CFUC, (c) there was no significant difference between the ability of bone marrow or peripheral blood T cells to inhibit CFUC, and (d) mitogens alone had either no effect or a moderate enhancing activity on marrow CFUC. These findings suggest that generation of CFUC suppressor T cells occurs normally within a few hours of polyclonal T cell stimulation.

Bone Marrow Cells↗
PubMed1984

Activation of lymphocytes by PPD and PHA is promoted by exudate from BCG-induced pleurisy.

Cell-free pleural exudate (PE) obtained from guinea pigs with BCG-induced pleurisy was tested for influence on in vitro activation of lymphocytes by PHA and PPD. A previous study has shown poor activation of lymphocytes derived from pleural exudate and this was thought possibly to depend on inhibitory activity of the exudate. Instead of the expected suppressive effect, however, PE in the present study promoted activation of lymphocytes from most sample sites in healthy and pleuritic guinea pigs. Thus, in the presence of PE, lymphocytes derived from the pleural exudate were always activated in vitro by PHA and PPD.

Animals↗
PubMed1984

[Sensitization by repeated skin tests with candidin and PHA].

Intra-dermal skin tests (IST) were applied with candidin (1:100) in 37 subjects and repeated 10 days later. The induration diameter of the second injection (read at 48 h) was greater (p less than 10(-8]. A correlation (r = 0.76, p less than 0.001) appears between the first and second induration diameters. In 17 of these patients (randomly distributed) we measured the absolute number of mononuclear cells bearing receptors of Fc IgG (RFc) before the first and before the second injection. The number of RFc was greater (p less than 0.02) after the second injection. It may be possible that candidin testing increase T suppressor cells. In 20 other subjects, we observed an increase of induration diameter (p less than 0.05) after a second IST of PHA (2 micrograms) applied 15 days after the first injection. Repeated IST with candidin and PHA induce a very high level of booster phenomenon. This fact may be kept in mind when interpreting serial IST in immunodeficiencies.

Aged↗
PubMed1983

Age-related changes in PHA and allogeneic reactivity of human T lymphocytes.

In fifty-four healthy individuals aged from 22 to 53 the response of lymphocytes to PHA stimulation and to stimulation with allogeneic lymphocytes were determined. A linear age-related decrease in reactivity to PHA (r = 0.500, P less than 0.01), as well as to allogeneic stimulation (r = 0.351, P less than 0.01) was found. The correlation between these two parameters of T lymphocyte function was weak (r = 0.207, not significant).

Adolescent↗
PubMed1983

Effect of dapsone (DDS) on T-cells and their response to PHA and lepromin in tuberculoid leprosy patients.

T and B cell counts and their response to PHA and lepromin were studied in 46 patients of polar tuberculoid leprosy (TT), divided into two age and sex matched groups. Twenty five normal healthy controls were similarly investigated. While one group consisted of 26 untreated TT patients, the other included 20 individuals who had taken dapsone, 50 mg daily, for 12 to 14 months. There was significant decrease in the number of T-lymphocytes and their response to PHA and lepromin was lower in the treated, as compared to the untreated patients and normal persons. No significant change was found in the number of B-lymphocytes in any of the groups.

B-Lymphocytes↗
PubMed1983

Activity of nonspecific esterases in the marrow of mice following intraperitoneal administration of concanavalin A and PHA.

The activity of nonspecific esterases was studied in the bone marrow cells of mice after single intraperitoneal injections of Con A and PHA-M in the dose of 30 mg per 1 kg of body weight. Samples were collected 24, 72 and 120 hours after the injection of lectins. A cellular reaction to the activity of nonspecific esterases was tested after the method of Heckner using naphthol chloroacetate AS-D as an esterase substrate. In the control group the cells belonging to the granulocytic system except these being in mature forms, showed an apparent activity. A negative esterase reaction was revealed also in megakaryocytes, monocytes and lymphocytes. The administration of Con A intensified the esterase reaction in the cells belonging to the granulocytic series, except the mature forms. The esterase activity appeared in megakaryocytes, monocytes and lymphocytes. Most numerous changes in the activity were noted 72 hours following the injection. PHA-M was found to exert a reverse effect, weakening the esterase reaction in comparison to both the controls and the Con A--group.

Animals↗
PubMed1978

Immuno-suppressive effect of human macrophages. II. Influence of macrophages on the kinetics of DNA, RNA and protein synthesis in PHA-stimulated lymphocytes.

Human macrophages obtained by culturing blood monocytes in vitro for 8 days release a soluble factor(s) inhibiting DNA synthesis and cell proliferation in PHA-stimulated lymphocytes. Synthesis of RNA and protein was strongly inhibited in PHA-stimulated lymphocytes sedimented on macrophages, as well as in lymphocytes separeted from the macrophages by a membrane, thus demomatrating that inhibition of RNA and protein synthesis was also mediated by a soluble factor(s). The kinetics of the factor-mediated inhibition showed that RNA synthesis was readily inhibited, whereas there was a delay in the inhibition of protein synthesis, thus indicating that the inhibition of protein synthesis and cell proliferation is a result of a blocking effect on the nucleic acid synthesis. The kinetics of DNA and protein synthesis in lymphocytes relieved from macrophage-mediated inhibition indicate a cytostatic effect.

Adult↗
PubMed1980

Age-dependent responsiveness of T lymphocytes to allogeneic and PHA stimulation.

In the course of family investigations a linear age-dependent decrease of reactivity against pooled allogeneic lymphocytes was found between 20 and 70 yr of age. This decreasing tendency was ascertained also by the investigation of unrelated people of a more advanced age. In the elderly, maximal transformation values in PHA stimulation investigated at different PHA doses showed a similar degree of reduction as allogeneic reactivity, and a good correlation between the two parameters of T-lymphocyte function has been found.

Adult↗
PubMed1980

Phytohaemagglutinin (PHA)-induced transformation of peripheral blood-lymphocytes in leprosy patients.

101 patients belonging to different types of leprosy were investigated for PHA-induced lymphocyte transformation in peripheral blood. There was a significant depression (P < 0.05) in blastogenesis in borderline (BB), borderline lepromatous (BL) and lepromatous (LL) patients. On the other hand, tuberculoid (TT) and borderline tuberculoid (BT) patients did not show any alteration in PHA-induced blastogenesis (P > 0.05) when compared to normal. The significance of these findings have been discussed.

Dapsone↗
PubMed1982

[Determination of active T lymphocytes in the peripheral blood by the AE rosette test. Correlation of the AE and E rosette tests with lymphocyte reactivity in vitro after PHA stimulation].

AE rosette test (Wybran and Fudenberg) detects T lymphocyte subpopulation and correlates with cellular immunity. In this study we found decreased percentage of active T lymphocytes mainly in peripheral blood of newborns, in children with frequent infections and with malabsorption syndrome. We tried to correlate AE and E rosette tests with PHA lymphocyte reactivity in vitro in 231 patients. We found that decreased PHA lymphocytes reactivity better correlates with decreased percentage of active T lymphocytes than with total number of T lymphocytes. Active rosette test (AE) can be usefull in evaluation of cellular immunity in children.

Adult↗
PubMed1982

The cells involved in the immune response of fish. III. Culture requirements of PHA-stimulated carp (Cyprinus carpio) lymphocytes.

The optimalization of the culture conditions for carp peripheral blood lymphocytes was studied using the thymidine uptake technique. The quantitative and/or qualitative requirements of this culture were determined with respect to the source of serum, the concentrations of 2-ME, glutamine and PHA, and with respect to the initial cell density. High individual variations, shown along the experiments, pointed out the existence of low and high responders to the mitogenic stimulus. These individual variations were considerably reduced and the mitogenic response extremely enhanced by the addition to the culture medium of optimal concentrations of charcoal adsorbed pooled homologous serum (4%), 2-ME (125-250 microM), glutamine (8 mM), PHA (10-40 microliter per ml culture, for the batch used) and by seeding the cells at the optimal density of 2 x 10(5) per microplate well. Finally, the kinetics of cell growth were studied at optimal concentrations of all these factors. The peak response was obtained between days 6 and 7 at 28 degrees C, and the mean doubling time at the exponential phase of the culture, at this temperature, was about 14 hours.

Animals↗
PubMed1981

Sequential activation of human peripheral lymphocytes displaying two distinct euchrysine binding patterns in PHA-stimulated cultures.

The patterns of supravital staining with euchrysine, a fluorescent dye thought to bind preferentially to membranes of lysosomes and other structures involved in endocytosis, were evaluated sequentially in PHA-stimulated cultures of human unseparated, T and non-T lymphocytes under conditions of a reversible, amethopterine-imposed DNA synthesis block. It was found that type I cells (with a single conglomerate of fluorescent granules, constituting approx. 50% of resting T cells) were almost completely replaced by type III cells (with large conglomerates of coarse granules, typical of lymphocytes undergoing blast transformation) up to the end of second day of culture. Type II cells (with very fine fluorescent granules scattered over the cytoplasms, present in about 50% of T and all non-T lymphocytes) did not initially change their number but later were replaced by type III cells, usually starting from the third day of culture. A hypothesis is discussed according to which only type I cells are primarily responsive to PHA, whereas type II cells require "help" from the former, prior to transition into the proliferative stage.

Acridine Orange↗
PubMedDate not supplied

In vitro responses of lymphocytes in juvenile arthritis: effects of time and concentration of PHA-P.

The effects of concentration of PHA-P and time in culture on cells from patients with systemic, polyarticular and pauciarticular juvenile arthritis have been studied. Responses to suboptimal concentrations are depressed at 3 days, particularly of systemic and polyarticular patients, but normal by 5 days and probably prolonged at 7 days. The responses approach normal with 5 micrograms/ml PHA-P. This delay also occurs in cells from children with cystic fibrosis and acute pneumonia and so is not disease specific. Kinetic studies show a slower recruitment of cells. The delay is corrected by 1 microgram/ml indomethacin. After 7 days, cultures from patients with juvenile arthritis have fewer E, heat-stable E, and EAC rosetting cells than do cultures from normal children or children with cystic fibrosis.

Adolescent↗
PubMed1980

Rosette-increasing factor released by PHA-stimulated mononuclear cells in vitro which augments active E and EA rosette formation.

The supernatants of phytohaemagglutinin (PHA) stimulated mononuclear (MN) cells contained a factor that significantly increased active E and EA (IgG) RFC which belonged to T cells and such was termed 'rosette-increasing factor' (RIF). This factor was demonstrated after as early as 2 hr of cluture and remained stable thereafter. The production of the factor seemed to be independent of macrophages and was mainly by nylon wool-adherent T cells. Cycloheximide and cytochalasin B pretreatment of MN cells prior to the addition of PHA abolished the activity of the supernatants in a dose-dependent manner, whereas mitomycin C and colchicine had no effect. As active E-RFC and Fc (IgG) receptor-positive T cells are considered to be closely correlated with cell-mediated immunity, this factor may play an important role in cellular immune response.

Cells, Cultured↗
PubMed1980

Effect of bile acids on E rosette formation and PHA stimulation.

The effect of bile acids on E rosette formation and lymphocyte response to PHA was studied. Pooled conjugated and unconjugated bile acids decreased normal lymphocyte E rosette formation in vitro. This inhibition is related to bile acid concentration. Unconjugated bile acids induced a depression of PHA stimulation in comparison to controls. These findings suggest that bile acids can play a role in the depression of cellular immunity observed in patients with cholestasis.

Animals↗
PubMed1995

Fastigiofugal projection to the brainstem nuclei in the cat: an anterograde PHA-L tracing study.

Fastigial projections to brainstem nuclei were studied using an anterograde neural tracer, Phaseolus vulgaris leucoagglutinin (PHA-L). Microinjections of PHA-L were made into the rostral pole, and middle and caudal parts of the left fastigial nucleus in cat. In addition to fastigioreticular and fastigiovestibular projections, fastigiofugal projections to cranial motor nuclei (IV, VI and VII) and those nuclei involved in autonomic control were identified. At the medullary level, a topographic arrangement of fastigioreticular projection was observed. Rostral and caudal parts of the fastigial nucleus projected to the ventral and dorsal parts of the medial reticular formation, respectively. Fastigiofugal fibers which originated from the rostral part of the fastigial nucleus innervated heavily the nucleus reticularis gigantocellularis (NRGc), nucleus reticularis magnocellularis (NRMc) and the ventral paramedian reticular nucleus (PRN). Those fibers from the middle part innervated heavily the ventrolateral vestibular nucleus (VLV), NRGc, NRMc, ventral and dorsal PRN and parasolitary tract nucleus. From the caudal part of the fastigial nucleus, projections to the cranial motor nuclei (IV, VI and VII), VLV and inferior vestibular nucleus were observed.

Animals↗
PubMed1975

The effect of in vitro irradiation on the responses of human lymphocytes to PHA, PPD and allogeneic cells.

The effect of X-ray, cobalt and 45 MeV electron irradiation on the responses of lymphocytes to PHA, PPD and allogeneic cells was studied using a semimicro lymphocyte culture technique. The responses to PPD and allogeneic cells were found to be more sensitive to irradiation than the response to PHA, even when the time factor was taken into account, i.e. the effect of irradiation was measured on the same day irrespective the type of stimulation. At the doses used, 500, 3000 and 6000 rd, there was no difference between the effects of the three types of radiation used. The possible explanations for the findings are discussed.

Aniline Compounds↗