Intraperitoneal Administration of Adjuvant Inhibits the Development of Adjuvant Arthritis in Rats

In recent years, considerable efforts have been made to develop effective therapy for autoimmune diseases by specific suppression of the autoreactive immune process without affecting the remainder of the immune system. In our study we evaluated the protective effects and therapeutic potential of Mycobacterium butyricum (Mb), the causative antigen inducing adjuvant arthritis (AA), an experimental model of autoimmune disease in the rat. The antigen was administered to rats by a different route and at concentrations 10 and 100 times lower than the inducing one. Arthritis was induced by injection of 0.6 mg of Mb in paraffin oil into the hindpaw, and the severity of disease was assessed by measurement of contralateral paw swelling every three days and primary and secondary lesions were scored on an arbitrary scale after 14, 21, and 28 days. Animals were assigned to different groups and treated intraperitoneally with different doses and schedules of Mb. The administration of 60 μg of Mb every two days, starting 6 days before arthritogenic injection until the second day after, led to a significant inhibition of the arthritic process (p< 0.001 of the arthritic index). Treatment of animals with 60 μg of Mb every two days, from day 2 to day 21 after arthritis induction caused almost total suppression of lesions. However, in both treatment schedules, animals showed important signs of peritoneal inflammation. The administration of single injection of 60 or 6 μg of Mb 10 days after arthritis induction led to an inhibition of arthritic index reaching the maximum percentage on day 14 (26% and 24% with 60 and 6 μg respectively) and was able to delay the development of oedema foot volume, without signs of local inflammation. These results confirm the ability to modulate the autoimmune process even when the immunological response is far advanced, suggesting new strategies in the therapy of human autoimmune diseases.

Stimulus-specific regulation of CD63 and CD203c membrane expression in human basophils by the flavonoid quercetin

BACKGROUND

Flavonoids, such as quercetin, were reported to inhibit histamine release and cytokine production by basophils, but there is no evidence describing their action on membrane markers and intracellular biochemical pathways.

OBJECTIVE

The aim of the study was to examine the effect of several quercetin doses on an in vitro human basophil activation system that evaluates up-regulation of membrane markers in response to agonists.

METHODS

Leukocyte buffy coats from K(2)-EDTA anti-coagulated blood were treated with different concentrations of quercetin and triggered with anti-IgE ("allergy model") and with N-formyl-Met-Leu-Phe (fMLP) ("inflammation model"). Basophils were captured as CD123(bright)/HLA-DR(non-expressing) cells in a flow cytometry analysis and fluorescence values of CD63-FITC, CD203c-PE and CD123-PECy5 were used to produce dose response curves.

RESULTS

Quercetin at a dose of 10 microg/ml strongly inhibited CD63 and CD203c membrane up-regulation triggered by both agonists, but it neither affected cell viability nor changed the expression of the phenotypic marker CD123. The anti-IgE model appeared highly sensitive to the effect of quercetin: a dose as low as 0.01 microg/ml was able to significantly decrease CD63 and CD203c membrane expression. In the fMLP model the dose response was different: quercetin doses from 0.01 to 0.1 microg/ml significantly increased up-regulation of membrane markers, achieving the highest effect with CD63.

CONCLUSION

Very low doses of quercetin, within the pharmacological range, inhibit IgE-mediated membrane marker's up-regulation but prime the response to the chemotactic peptide fMLP; this stimulus specificity may have implications on the possible therapeutic action of the flavonoid in different pathologies.

Cell contact-dependent PMN HLA-DR and CD69 membrane expression induced by autologous mono-lymphocytes and cell lines

Polymorphonuclear granulocytes (PMN) are commonly considered short-lived cells playing an efficient role in primary host defense via phagocytosis and release of cytotoxic compounds and inflammatory cytokines. Purified PMN do not express HLA-DR and CD69 molecules on cell surface, but they can be induced to do so by co-culture with peripheral blood derived mono-lymphocytes. De novo cell-surface expression of HLA-DR was also induced in PMN by co-culture with cell lines of lymphoid phenotype, but not with cell lines of myeloid phenotype. CD69 expression was not induced by co-culture with any of the cell lines used in the present study. In addition, we have observed induction of HLA-DR surface expression on PMN by culture in presence of culture supernatant of one of the cell lines of lymphoid origin, RPMI-8866. Quantitative analysis of HLA-DR and CD69 expression in stimulated PMN allowed us to divide PMN donors in two main groups, one with low expression and the other with high expression of the two molecules. HLA-DR surface expression was not altered by treatment with CHX and BFA, and RT-PCR analysis of total RNA from resting and stimulated PMN with RPMI-8866 supernatant did not detect the presence of any specific HLA-DR and CIITA transcript. Flow-cytometry and fluorescence microscopy analysis of resting PMN revealed the presence of HLA-DR molecules localized in intracellular vesicular-tubular structures. These data show that a reservoir of HLA-DR molecules is stored in the cytoplasm of human resting PMN and can be released to reach cell surface by a mobilization mechanism induced by cell surface interactions with selected cell types and sometimes with molecules released in culture supernatants.

CD23 and CD69 expression on human neutrophils of healthy subjects and patients with peripheral arterial occlusive disease

In this work we studied, on human neutrophils from healthy donors and patients with peripheral arterial occlusive disease, the expression of CD23 and CD69 and the modulatory effects of IFN-gamma, GM-CSF and IL-4. Neutrophils were isolated from 9 patients and 9 healthy subjects and cultured for 24 h in absence or presence of IFN-gamma (1000 U/ml), GM-CSF (10 U/ml) and IL-4 (10 ng/ml). Expression of CD23 and CD69 was analyzed by FACScan cytofluorimeter. Neutrophils of both patients and healthy donors resulted negative for CD23 and CD69 expression immediately after isolation. After 24 h without stimuli, neutrophils from some patients and healthy donors expressed CD23 and CD69. IFN-gamma and GM-CSF had opposite effects on these two antigens, down-regulating CD23 and up-regulating CD69. IFN-gamma, GM-CSF and IL-4 were not able to induce CD23 expression, while CD69 expression was induced in some negative healthy donors and patients by IFN-gamma, GM-CSF and IL-4 respectively. From our data, we identified two subpopulations of neutrophils that, independently from the vascular pathology, showed a different behaviour towards temperature and some cytokines.

Cytokine and nitric oxide levels in a rat model of immunologic protection from adjuvant-induced arthritis

In the present study we investigated the correlation between the progression of adjuvant arthritis induced by Mycobacterium butyricum and the production of nitric oxide and some pro- and anti-inflammatory cytokines in arthritic rats and in rats treated with low intra-peritoneal doses of Mycobacterium 3 and 10 days after arthritis induction. The intra-peritoneal administration of Mycobacterium antigen significantly inhibited disease development. Compared to healthy rats, a rise in serum and peritoneal pro-inflammatory cytokines was observed in all arthritic rats already from the 14 day. The treatment with intra-peritoneal Mycobacterium was associated with a significant reduction in IL-6 serum concentrations and a slight decrease of IFN-gamma production by peritoneal macrophages. Nitrite/nitrate plasma and peritoneal levels were significantly higher in all arthritic rats. Intra-peritoneal administration of Mycobacterium caused a further increase in nitrite/nitrate plasma concentrations, while no differences were evident in nitric oxide production by peritoneal macrophages. From our data it is evident that among the variables here investigated, IL-6 seems to be the more representative marker of the disease and of the treatment effect. A possible role of nitric oxide as a modulator rather than a direct mediator in this model of inflammation is discussed.

Defective platelet response to arachidonic acid and thromboxane A(2) in subjects with Pl(A2) polymorphism of beta(3) subunit (glycoprotein IIIa)

The membrane complex alpha(IIb)beta(3) is the major receptor for fibrinogen and is involved in platelet adhesion and aggregation. Evidence has been presented that the Pl(A2) allele of the beta(3) Pl(A1/A2) gene polymorphism might be an independent risk factor for coronary thrombosis, but the matter is still controversial. We investigated the relationship between this polymorphism and possible alterations of platelet functions in vitro. The platelet adhesion to fibrinogen-coated microplate wells and the aggregation induced by several different agonists were tested in 63 healthy volunteers, among them, 49 subjects with Pl(A1/A1) polymorphism, 12 subjects with Pl(A1/A2) polymorphism and two subjects with (PlA2/A2) polymorphism. Subjects with PlA1/A2 polymorphism or with Pl(A2/A2) polymorphism showed significantly lower platelet responses as compared with Pl(A1/A1) subjects when either arachidonic acid or the thromboxane A(2) analogue, U46619, were used as agonists. In resting condition and after thrombin or ADP stimulation, platelet function was normal in all the subjects. An increased sensitivity to the anti-aggregatory effect of acetylsalicylic acid was observed in platelets from subjects with the Pl(A2) allele. Finally, using a flow-cytometric evaluation and determining the beta-thromboglobulin plasma levels, we did not find any evidence of a Pl(A2) platelet hyper-reactivity ex vivo. Our findings are not consistent with the hypothesis that the purported increase of cardiovascular risk in these subjects may be as a result of platelet hyperactivation. On the contrary, the Pl(A2) allele is associated with a platelet functional deficiency, specifically linked to the activation of the fibrinogen receptor by thromboxane A(2).

Expression of FCepsilonII/CD23 on human neutrophils isolated from rheumatoid arthritis patients

CD23, the low affinity receptor for IgE, is a 45 kilodalton molecule belonging to the C-type lectin family, some members of which have been identified as adhesion molecules. Since it has been described upregulated in different cells in chronic inflammatory diseases and in rheumatoid arthritis in particular, where neutrophils are directly involved in tissue damage, our interest, in this work, has been focused on the expression and regulation of this antigen on neutrophil membrane. We studied 22 patients suffering from rheumatoid arthritis and 22 healthy control subjects. CD23 expression on neutrophil membrane was analyzed by immunofluorescence. Neutrophils of 9 out of 22 patients expressed CD23 molecules, neutrophils of 11 out of 22 patients expressed CD23 only after 24 h of incubation in RPMI; only 2 out of 22 patients did not express the CD23 antigen on neutrophil membrane either after isolation or after a 24 h incubation. On the contrary neutrophils isolated from healthy subjects did not express CD23 molecules upon isolation. Only in 7/22 control subjects neutrophils resulted positive after 24 h of incubation in RPMI. Moreover, we found that in our experimental conditions the presence of IFN-g or GM-CSF alone or in combination with IL-4 inhibited CD23 expression during the 24 h incubation. Our results show that there is a strong association between neutrophil ability to express CD23 and rheumatoid arthritis, and that such expression may be regulated by GM-CSF, IFN-gamma and IL-4.

The F2-isoprostane 8-epiprostaglandin F2alpha increases platelet adhesion and reduces the antiadhesive and antiaggregatory effects of NO

F2-isoprostanes are prostaglandin (PG) isomers produced in vivo through free radical-catalyzed peroxidation of arachidonic acid, which may affect platelet function. The current study investigated the effects of 8-epiprostaglandin F2alpha (8-epi-PGF2alpha) on critical events of platelet activation. A dose-dependent increase in platelet adhesion to fibrinogen- and plasma-coated microwells by 8-epi-PGF2alpha (1 to 1000 nmol/L) was observed when resting platelets (plasma from 1.3+/-0.2% to 5.5+/-0.2%, EC50 of 48 nmol/L; fibrinogen from 3.3+/-0.3% to 6.4+/-0.2%, EC50 of 35 nmol/L; mean+/-SEM, n=8, P<0.001) and thrombin-stimulated human platelets were used. The expression of the adhesion molecule glycoprotein IIb/IIIa was increased by 10 to 1000 nmol/L 8-epi-PGF2alpha in resting platelets (from 64.8+/-2.1% to 83.9+/-1.3%; n=5, P<0.01) and in stimulated platelets. The secretion of the glycoprotein GMP-140 increased only in the presence of both thrombin and 10 to 1000 nmol/L 8-epi-PGF2alpha (from 48.5+/-3.1% to 63.1+/-2.0%, P<0.05). The antiaggregatory effects of both the NO donor NOR-3 (basal, 21.4+/-4.6%; with 8-epi-PGF2alpha, 30.8+/-6.9%; n=14, P<0.05) and endothelial cells that release NO (basal, 18.5+/-4.6%; with 8-epi-PGF2alpha, 30.7+/-5.3%; n=15, P<0.001) were also reduced. All of these effects were prevented by the thromboxane receptor antagonist GR32191 but not affected by acetylsalicylic acid. An increase in free intracellular calcium concentration, measured with the use of fura 2, was observed with 8-epi-PGF2alpha. In conclusion, F2-isoprostanes may participate in oxidative injury by inducing platelet activation and by reducing the antiplatelet activity of NO: increased platelet adhesiveness and expression of the fibrinogen receptor are induced by nanomolar amounts of 8-epi-PG-F2alpha. Platelet secretion and aggregation can also be induced in the presence of platelet agonists.

Phase-II randomized study of pre-operative IL-2 administration in operable NSCLC

Lymphocytopenia is a prognostic factor for shorter survival in advanced lung cancer and it is likely related to an interleukin-2 (IL-2) deficiency occurring during cancer progression. Major surgery itself for cancer is known to induce lymphocytopenia in the postoperative period. Postoperative lymphocyte decrease in colorectal cancer can be prevented by preoperative administration of recombinant human (rhIL-2), indicating that it is possible to drive appropriately important host defence agents during critical events, such as major surgery. The aim of this study is to verify if recombinant human interleukin-2 (rhIL-2) administered preoperatively is able to prevent the lymphocyte decrease occurring after radical surgery in operable lung cancer. This phase II study included 40 patients with operable NSCLC screened as stage II or IIIA, randomized to receive rhIL-2, 9000000 IU subcutaneously twice daily for 3 days before surgery (treated group, 20 patients) or not (control group, 20 patients). At baseline, there were no significant differences in total lymphocyte number and lymphocyte subsets (T-cell, T-helper, CD8+, natural killer, CD4/CD8 ratio) between groups. Postoperatively the control group showed a decrease in total lymphocyte count, T-lymphocyte count, T-helper cell number and CD4/CD8 ratio, significant at the 14th postoperative day relative to baseline values. In contrast, in the rhIL-2 treated group, at the 3rd and at the 14th postoperative days, a significant increase was observed over both baseline and control group values of total lymphocyte count, T-cells and T-helper cells. NK cell number increased significantly only over the control group. CD4/CD8 ratio was increased at the 14th postoperative day significantly over both baseline and control values. At pathological staging after surgery, four patients in the rhIL-2 group and four in the control group resulted in stage pIIIB; one patient in the rhIL-2 group resulted in stage IV (contralateral metastasis). Indeed, 15/20 rhIL-2 treated patients and 16/20 control patients were radically operated. After a 24-month follow-up, 12/20 rhIL-2 treated patients were alive and 8/15 radically operated were disease-free; 8/20 control patients were alive and 4/16 radically operated were disease-free. Toxicity was mild to moderate and easy manageable; treatment was suspended in one patient due to skin rash with hypotension grade II. The preoperative administration of rhIL-2 is feasible and prevents lymphocyte decrease occurring postoperatively after surgery for lung cancer. Further studies are required to assess the impact on survival.

A scientific reappraisal of the 'principle of similarity'

In the history of therapeutics, the 'principle of similarity'--the treatment of 'same by same' or of 'like by like'--may be traced back to a number of medical traditions, including the systems of Hippocrates, Paracelsus and Hahnemann. Although in recent years we have witnessed a renaissance of interest in traditional medicines and 'holistic' medical practices, the reliability of the principle of similarity has still to be demonstrated on experimental grounds, and very few studies have been conducted to understand the underlying mechanism(s). Acceptance of this phenomenon requires supporting evidence of possible mechanisms and high-quality studies exploring its effectiveness in clinical medicine. The aim of this work is to provide a rational approach to the analysis of the various aspects of this historical yet also modern medical principle, in order to construct a plausible framework of ideas capable of facilitating further basic and clinical research into this field.

Specific and long-lasting suppression of rat adjuvant arthritis by low-dose Mycobacterium butyricum

We have tested the therapeutic effect of intraperitoneal injections of Mycobacterium butyricum on the development of adjuvant arthritis in rats and we have explored the specificity and the duration of effectivity of this treatment. Rats with induced arthritis were injected intraperitoneally with the causative antigen, Mycobacterium butyricum, at concentrations 10 times lower than the inducing one, on the 3rd and 10th day after arthritis induction. The severity of the disease was assessed on the basis of physical (arthritis index, paw swelling) and biochemical (serum interleukin-6) parameters. The treatment with Mycobacterium butyricum led to a significant suppression of adjuvant-induced arthritis. This therapeutic effect was both antigen-specific, because intraperitoneal aspecific inflammation did not prevent the disease, and long-lasting. The results obtained in this model confirm the possibility of modulating the autoimmune process even when the immunological response is already triggered, suggesting new therapeutic strategies, more suitable than preventive vaccination, in human autoimmune diseases.

The antiplatelet effects of a new nitroderivative of acetylsalicylic acid--an in vitro study of inhibition on the early phase of platelet activation and on TXA2 production

We studied in vitro the antiplatelet activity of a new nitroderivative chemically related to acetylsalicylic acid: 2 acetoxybenzoate 2-[1-nitroxy-methyl]-phenyl ester (NCX 4016), in order to identify any effects due to the release of nitric oxide and the blockade of cyclo-oxygenase. The effects of scalar doses of NCX 4016 on the early phase of platelet activation, platelet aggregation and thromboxane A2 production were investigated. We observed inhibitory effects of NCX 4016 on platelet adhesion (IC50 = 7.3 x 10(-5) M), platelet cytosolic calcium concentration, assayed by fluorescent probe Fura 2, and the expression of glycoprotein IIb/IIIa (CD41/alpha IIb beta 3) (IC50 = 3.4 x 10(-5) M) and P-selectin (CD62/GMP-140) (IC50 = 4.9 x 10(-5) M) measured by flow cytometry. NCX 4016 also prevented thrombin-induced platelet aggregation (IC50 = 3.9 x 10(-5) M). None of these parameters were affected by acetylsalicylic acid. These inhibitory activities of NCX 4016 were abolished by oxyhaemoglobin and methylene blue. Intracellular cyclic GMP observed during thrombin-induced aggregation was increased by incubation with NCX 4016. These results appear to be attributable to the release of nitric oxide, which activates soluble platelet guanylylcyclase and promotes intracellular cyclic GMP increase. NCX 4016 almost completely inhibited platelet thromboxane A2 production and arachidonic acid-induced platelet aggregation. This also occurred in the presence of oxyhaemoglobin and methylene blue, indicating that its antiplatelet activity can be attributed not only to nitric oxide release but also to cyclo-oxygenase inhibition.

Study of platelet adhesion in patients with uncomplicated hypertension

OBJECTIVE

To evaluate platelet function in patients with essential hypertension by sensitive methods investigating platelet adhesion and expression of some platelet glycoproteins (GP), namely GPIIb/IIIa (CD41/alpha 2 beta 3) and GMP-140 (CD62/P-selectin/PADGEM). Other markers of platelet (beta-thromboglobulin) and endothelium activation (von Willebrand factor) were also measured.

METHODS

We studied 21 uncomplicated essential hypertensive patients and 20 healthy normotensive control subjects, non-smokers, matched for age and sex. Resting and stimulated platelet adhesion was performed with a colorimetric method using the activity of platelet acid phosphatase for the determination of the number of platelets adhering to human plasma- or fibrinogen-coated microwells. Platelet activation was characterized by flow cytometric measurement of GPIIb/IIIa and GMP-140 in whole blood and washed platelets suspensions, with antihuman fluorescent monoclonal antibodies.

RESULTS

Thrombin-stimulated platelet adhesion to human plasma-coated microwells was significantly higher in hypertensive patients than in control subjects (0.05 U/ml thrombin: 13.4 +/- 1.0 versus 7.7 +/- 0.6% adhesion; 0.1 U/ml thrombin: 19.4 +/- 2.3 versus 12.6 +/- 1.8%; means +/- SEM), whereas platelet adhesion to fibrinogen-coated wells did not differ in the two groups. Flow-cytometry analysis of whole blood demonstrated a significantly increased expression of GMP-140 in hypertensive patients compared with normal subjects (percentage of CD62+ platelets: 7.3 +/- 1.2 versus 3.7 +/- 1; means +/- SEM), whereas the expression of GPIIb/IIIa did not differ in the two groups (percentage of CD41a+ platelets: 72.5 +/- 4.5 versus 70.4 +/- 3.9). Moreover, flow cytometry showed an increased size of platelets in hypertensive patients compared with that in control subjects (forwards scattering: 46.5 +/- 1.5 versus 38.9 +/- 1.1; means +/- SEM). Flow-cytometric evaluation of washed platelet suspensions showed no statistically significant differences between the expression of GMP-140 and GPIIb/IIIa in the two groups. beta-Thrombo-globulin plasma levels were higher in hypertensive patients than they were in normal subjects (36.3 +/- 2.0 versus 28.2 +/- 1.3 ng/ml; means +/- SEM). Von Willebrand factor plasma levels were not significantly different in the two groups (101.2 +/- 10.3 versus 86.3 +/- 5.6 U/dl).

CONCLUSIONS

These findings provide further evidence that there is a significant, albeit weak, platelet activation in hypertensive patients compared with normal subjects.

Dual effects of diclofenac on human platelet adhesion in vitro

The effect of two non-steroidal anti-inflammatory drugs on the adhesion function of human platelets was evaluated. Platelets isolated from healthy human subjects were treated for 10 min with the indicated drugs and then incubated in fibrinogen-coated microwell plates in the absence or in the presence of ADP (10 microM) and thrombin (0.05 U/ml). After 1 h of incubation, adherent platelets were measured using an enzymatic assay. ADP- and thrombin-stimulated adhesion was significantly inhibited by high doses ( > 500 microM) of diclofenac, while doses ranging from 50 to 300 microM stimulated adhesion in the absence of agonists (resting platelets). A similar stimulatory effect on platelet adhesion was observed also with 200-500 microM flurbiprofen. Moreover, immunocytofluorimetry demonstrated that diclofenac dose-dependently (100-500 microM) induced the expression of GMP-140 and increased the expression of GPIIb/IIIa on the membrane of unstimulated platelets. High doses ( > 500 microM) of this drug inhibited thrombin-stimulated expression of GPIIb/IIIa and GMP-140.

Increased in vitro neutrophil adherence in a case of chronic idiopathic neutropenia

In this report we describe a patient with persistent neutropenia whose neutrophils showed increased adhesion in a microplate assay. In three separate assays, from 12.5% to 13.7% of the patient's blood neutrophils exhibited spontaneous (unstimulated) adhesion to fetal bovine serum-coated microplate wells, much higher than adhesion of cells from healthy controls (1.9% +/- 2.5 SD, n = 20). The difference of spontaneous adhesion between the patient's and control neutrophils was even higher when cells from a skin-window exudate were examined (patient: 42.1-100% adhesion; control: 3.6% +/- 3.5 SD, n = 20). Over 80% inhibition of the increased adhesion was produced by the 60.3 anti-CD 18 monoclonal antibody, suggesting an involvement of beta 2-integrins.

Susceptibility of human-mouse T cell hybrids to HIV-productive infection

Interspecies human x mouse cell hybrids were used to investigate the genetic basis of human permissivity to HTLV-IIIB infection. T cell hybrids between the mouse BW 51.47 T lymphoma line and normal, PHA-IL-2 activated, human peripheral mononuclear cells (PBMCs) were generated. These hybrids preferentially segregated human chromosomes, as assessed by phenotype and karyotype analysis. Viral integration occurred only in those hybrids expressing CD4+ at the cell surface. However, infectious progeny production was demonstrated only in two of the three CD4+ hybrids tested. By segregation analysis, we could correlate the absence of human chromosomes 1, 3, and 9 with the lack of infectious viral progeny.

Hypothalamic-pituitary-gonadotropic function in girls with premature thelarche

Hypothalamic-pituitary-gonadotropic activity was investigated in 9 girls with premature thelarche, and compared with that in 9 healthy girls and 6 girls with true precocious puberty. The gonadotropin stimulation test with luteinising hormone-releasing hormone was used. Girls with premature thelarche showed luteinising hormone response resembling that of normal girls, and follicle-stimulating hormone (FSH) response quite similar to that of girls with precocious puberty. This suggests that in premature thelarche there is a partial activation of the diencephalic-hypophyseal-gonadal axis, which affects FSH only. Premature thelarche therefore, should be considered as one of the disorders due to altered sensitivity of the hypothalamic receptors which regulate sex maturation.