Stimulation Of Lymphocyte Transformation Research Articles

Investigations into lymphocyte transformation and histamine release by basophils in sheep repeatedly infested with Rhipicephalus evertsi evertsi ticks

The immune response of a natural host of Rhipicephalus evertsi evertsi to feeding by this tick species was investigated with respect to the effects of tick salivary gland extracts on the transformation of peripheral blood lymphocytes and the release of histamine by basophils obtained from repeatedly infested sheep. The results indicated that there was no stimulation of lymphocyte transformation but that histamine release was elevated 10 fold after four infestations. Although this suggests a hypersensitivity reaction, believed to be a major factor in resistance to tick feeding, it was observed that ticks fed normally even after four infestations with 28 day intervals in between. These results emphasize the adaptation of ticks to feeding on their natural hosts.

Evaluation of relationship between plasma fibrinogen concentration and tuberculin testing in red deer

Summary After intradermal injection of bovine purified derivative (ppd), increases in plasma fibrinogen concentration and plasma viscosity developed in red deer (Cervus elaphus) with a history of tuberculosis caused by Mycobacterium bovis. Serum haptoglobin concentrations were also found to increase under similar circumstances. The increases were reproducible and did not appear to be related to mustering, stress, or the handling associated with injection of ppd. A significant (P < 0.05) direct relationship was found between the increase in plasma fibrinogen concentration and various markers of bovine tuberculosis infection, such as stimulation of lymphocyte transformation in response to bovine ppd and the diameter of intradermal tuberculin skin test reactions. A stronger correlation (P < 0.01) was found with the volume of intradermal tuberculin skin test reactivity, and the strongest correlation (P < 0.001) was with the presence of circulating antibovine ppd antibody.

Effect of zinc on the immune status of zinc-depleted AIDS related complex patients

Zinc deficiency has been recently reported in AIDS patients to be associated with a decrease in T helper cells. The effect of zinc supplementation was evaluated in 5 ARC patients and 5 control subjects using lymphocyte subset counts, blast transformation and chemiluminescence of polymorphonuclear leukocytes. Zinc was analysed by atomic absorption spectrophotometry. T-cell subsets were quantified by cytofluorometry. Chemiluminescence of PMN was measured by phagocytosis of opsonized zymosan. The ARC patients had significantly lower zinc concentrations in the RBC prior to supplementation (p < 0.05). This level increased following the administration of zinc gluconate. This increase was accompanied by (i) an increase in HLA.Dr + cells with no CD4 CD8 ratio alteration; (ii) a stimulation of lymphocyte transformation and PMN chemiluminescence particularly after 15 days' high zinc supplementation. Such a reconstitution in specific and non specific immune functions in ARC patients may warrant further investigation.

IMMUNOLOGIC EFFECTS OF VINYL CHLORIDE IN MICE

Male CD-1 mice were exposed to 10, 100 or 1000 ppm vinyl chloride (VC) for 2--8 weeks at 6 hr/day, 5 days/week. A slight increase in the spleen weight of mice was noted at the highest exposure level. Spleens were obtained from these animals (4 mice/group after 2, 4, and 8 weeks of exposure) and their lymphocytes cultured in vitro with or without the presence of phytomitogens, phytohemagglutinin (PHA) and pokeweed mitogen (PWM). Relative blast formation and the DNA synthesis was measured by the incorporation of 3H-thymidine in the cultured cells. The response of splenic lymphocytes to the phytomitogens was increased several-fold by VC exposure. The effects were apparent at 1000 ppm VC after 2 weeks of exposure and at all levels of VC exposure after 4--8 weeks. The effects were generally more pronounced at 100 ppm VC exposure than those at 1000 ppm. In vitro culture of splenic lymphocytes from control or VC-exposed mice in the VC atmosphere did not show an enhancement of blast formation. Alteration of VC metabolism during the VC exposure in vivo yielded results that indicated that metabolites of VC may be responsible for the stimulation of lymphocyte transformation observed in splenic cultures.

Immunological aspects of juvenile periodontitis (periodontosis).

Cell‐mediated and humoral immunological investigations were carried out in 34 patients with advanced destructive periodontal disease. In 23 of these patients, 14 to 21 years old, juvenile periodontitis was diagnosed by clinical and radiological criteria. Stimulation of lymphocyte transformation by autologous plaque, Veillonella alcalescens, Fusobacterium fusiforme and Bacteroides melaninogenicus was impaired, the response to Actinomyces viscosus was intact, but those to unrelated antigens, such as purified protein derivative (PPD) or Herpes simplex virus type 1 (HSV1) and to phytohaemagglutinin (PHA), were enhanced. However, lymphocytes stimulated by these antigens relased a factor causing macrophage migration inhibition in up to 65 % of patients. Substititution of autologous serum by homologous or fetal calf serum did not increase lymphocyte transformation, but was associated with conversion of the negative to positive macrophage migration inhibition activity, so that the latter was found in 80 % to 100 % of patients. Serum IgM, IgG and IgA concentrations were significantly increased and the haemagglutinating titres to related bacteria were higher than those found in controls.Comparable cell‐mediated and humoral immune responses were found in 11 patients, 22 to 29 years old, whose clinical and radiological features were similar to those in patients with juvenile periodontitis; the disease in these patients can be referred to as ‘post‐juvenile periodontitis’. The results suggest that in juvenile periodontitis a selective impairment of antigen induced DNA synthesis of lymphocytes to plaque and some Gramnegative organisms, is associated with release of macrophage migration inhibition factor.

Stimulation of Lymphocyte Transformation by Streptococcal Type M1 Protein: Relationship to HL-A Antigens

Abstract M1 protein isolated from group A streptococci, type 1, stimulates human peripheral blood lymphocytes in short-term tissue culture to undergo a dose-dependent increase in DNA synthesis. The degree of this lymphocyte stimulation is not related either to HL-A phenotype, the serum anti-M1 titer of the lymphocyte donor, or the effectiveness of M1 antigen in blocking the cytotoxic activity of HL-A alloantisera. However, both HL-A allo- and heteroantisera are highly effective in specifically inhibiting M1 mitogenic activity. This inhibitory effect clearly depends on anti-HL-A antibody since HL-A alloantisera are rendered ineffective when specifically absorbed with cultured human lymphoid cells. The mechanism by which anti-HL-A antibodies suppress the M1-induced lymphocyte transformation is thought to involve a masking of the M1 protein's mitogenic site such as to prevent interactions with specific lymphocyte receptors required for induction of the proliferative response.

Cell-mediated immunity in Herpesvirus hominis infections.

The cell-mediated and antibody responses to Herpesvirus hominis type 1 were investigated in patients with primary and recurrent herpetic infections. Stimulation of lymphocyte transformation with the virus and the complement fixing antibody titre did not differ significantly between patients and controls. However, macrophage migration inhibition and lymphocyte cytotoxicity were impaired in patients. The defects were specific to H. hominis, as Candida oblicans, which was used as an unrelated antigen, failed to show a similar abnormality. These results and preliminary sequential studies suggest that the susceptibility to recurrent herpesvirus infection may be due to an impaired production of macrophage migration inhibition factor and lymphocyte cytotoxicity in the presence of intact lymphocyte sensitization and antibody formation.

Cross-linkage in lymphocyte transformation.

A polymerized fraction of the non-stimulatory univalent Fab' fragment of goat antibody directed to rabbit Fab was as effective as the parent antibody in stimulating transformation of rabbit peripheral lymphocytes. The specificity of the stimulation initiated by the polymerized Fab' was shown by the ability of rabbit IgG to completely block its stirnulatory capacity and by the inability of polymerized non-specific goat IgG or its Fab' fragment to effect transformation. Polymerization of the IgG fraction of goat anti-rabbit Fab resulted in a fraction which was more stimulatory, at low concentrations, than the IgG from which it was derived. The data suggest that bivalence is a requirement for initiation of transformation by antiglobulin reagents. Further, the data suggest that, at low concentrations, the extent of DNA synthesis stimulated by a mitogen may to a large extent be directly related to the valence of the mitogen. It is suggested that stimulation of lymphocyte transformation by antigen is also a fun...

“Nonspecific” Stimulation of Lymphocyte Transformation by Cellular Fractions and Acid Extracts of Group a Streptococci

Abstract Hot hydrochloric acid extracts of group A streptococcal cells of types 5, 12 and 19 induced “nonspecific” blast-transformation and increased thymidine-14C incorporation by adult and cord blood lymphocytes of normal human donors. A similar degree of transformation was induced by preparations of streptococcal cell walls and cell membranes and by hot acid extracts of these cell components. Streptococcal cytoplasm was found to contain an inhibitor of phytohemagglutinin-induced transformation and of spontaneous transformation of cord blood lymphocytes. Treatment of streptococcal cytoplasm with hot hydrochloric acid resulted in the appearance or release of lymphocyte transforming activity in such preparations. The lymphocyte transforming activity of streptococcal acid extracts was unaffected by digestion with ribonuclease, trypsin, chymotrypsin, and pepsin. After gel filtration on Sephadex G-75, acid extracts of streptococcal cell membranes, cell walls and cytoplasm all exhibited their major transforming activity in a peak with maximum at Kd 0.36, suggesting a similar average molecular size for the transforming agent or agents derived from these components. The “nonspecific” mitogenic activity of acid extracts of streptococcal cells resembled that of streptolysin S preparations with respect to enzyme susceptibility and dose-response. Hot acid-treated streptolysin S preparations retained most of their transforming activity, while their hemolytic activity was completely destroyed. These data raise the possibility that the transforming activities of streptococcal cell acid extracts and of streptolysin S preparations are attributable to a similar or identical constituent.

Stimulation of lymphocyte transformation by bacterial antigens in patients with periodontal disease

Leucocytes were cultured from patients with chronic gingivitis or periodontitis and from matched healthy subjects. Lymphocyte transformation, induced by ultrasonicates of oral bacteria, was measured by 14C thymidine uptake. Odontomyces viscosus, Veillonella alcalescens, Bacteroides melaninogenicus and Fusobacterium fusiforme induced specific stimulation of lymphocytes in patients with gingivitis or mild or moderate periodontitis. However, in patients with severe periodontitis, lymphocyte transformation was significantly depressed when compared with mild or moderate periodontitis. Lactobacillus acidophilus and Proteus mirabilis failed to stimulate lymphocyte transformation. The cell-mediated immune response to some oral microorganisms may play a protective or aggressive part in the pathogenesis of periodontal disease.

Stimulation of lymphocyte transformation by 1-fluoro-2,4-dinitrobenzene.

Les lymphocytes du sang peripherique des cobayes sensibilises au 1-chloro-2,4-dinitrobenzene ont ete conjugues avec 1-fluoro-2,4-dinitrobenzene et ensuite cultives in vitro pendant 5 jours, a partir du moment ou on a observe en culture de 8–22% de cellules transformees.