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M Cassin

Publications and source records attributed to M Cassin.

At least 19 recordsLinked to original sources
PubMed2001

Increased interleukin 5 production in eosinophilic Sézary syndrome: regulation by interferon alfa and interleukin 12.

BACKGROUND: Peripheral eosinophilia occurs in a small subpopulation of patients with cutaneous T-cell lymphoma (CTCL) and denotes a poor prognosis. Clinical studies have suggested that the Sézary cell is a T(H)2 type helper T cell that produces cytokines that enhance the differentiation and activation of eosinophils. Interferon alfa (IFN-alpha) and interleukin 12 are effective therapeutic agents for CTCL and other hematologic disorders. OBJECTIVE: Our purpose was to determine the inhibitory activity of IFN-alpha and IL-12 on IL-5 production in vitro by peripheral blood mononuclear cells (PBMCs) obtained from patients with CTCL and eosinophilia. METHODS: Suppression of IL-5 production by IFN-alpha and IL-12 was assessed by comparing IL-5 production by PBMCs from patients with Sézary syndrome and eosinophilia when cultured alone or in the presence of either IFN-alpha or IL-12. RESULTS: A marked increase in IL-5 production by PBMCs from patients with Sézary syndrome and eosinophilia was observed. IL-5 production was markedly reduced when PBMCs were exposed to IFN-alpha or IL-12. CONCLUSION: These results suggest that IFN-alpha and perhaps IL-12 may produce a therapeutic response in patients with CTCL and eosinophilia through direct suppression of IL-5 production by malignant Sézary cells.

Cells, Cultured↗
PubMed2001

Complete molecular remission during biologic response modifier therapy for Sézary syndrome is associated with enhanced helper T type 1 cytokine production and natural killer cell activity.

BACKGROUND: Cutaneous T-cell lymphoma (CTCL) is a clonally derived, skin-invasive malignancy of CD4(+) T lymphocytes with the phenotype of mature helper T cells. Advancing stages of CTCL are associated with depressed cell-mediated immunity, increased production of T helper type 2 cytokines and decreased levels of T helper type 1 cytokines. OBJECTIVE: Our purpose was to evaluate the cytokine secretion pattern and cell-mediated cytotoxicity in peripheral blood mononuclear cells of patients with Sézary syndrome in relation to the presence of the malignant clone. METHODS: Serial polymerase chain reaction for the T-cell receptor-beta or T-cell receptor-gamma gene rearrangement was used to determine the presence of the malignant clone. Enzyme-linked immunosorbent assays were used to determine the levels of interleukin 4 and interferon gamma produced by the peripheral blood mononuclear cells from the patients with Sézary syndrome. RESULTS: We demonstrate 3 cases of Sézary syndrome with typically suppressed cell-mediated cytotoxicity, elevated production of interleukin 4, and depressed production of interferon gamma by their peripheral blood mononuclear cells before institution of therapy with biologic response modifier therapy. In all 3 cases after clinical and molecular remission, we observed striking immunologic changes, including an increase in levels of natural killer cell activity and interferon gamma production and decreased production of interleukin 4. CONCLUSIONS: The observation that the cytokine secretion pattern by peripheral blood mononuclear cells from 3 patients with Sézary syndrome normalized with the disappearance of the malignant clone from the peripheral blood suggests that the malignant T cells account for the aberrant cytokine production. Moreover, the aberrant cytokine production may be the cause for suppression of cell-mediated immunity seen in advancing stages of CTCL.

Aged↗
PubMed2000

Validation of the ejection fraction-velocity ratio: a new simplified "function-corrected" index for assessing aortic stenosis severity.

A new echocardiographic method for the evaluation of aortic stenosis (AS) severity has recently been introduced: the fractional shortening-velocity ratio (FSVR = fractional shortening/4 Vmax(2)). An important advantage of the method is the possibility of avoiding the difficulties related to the measurement of left ventricular outflow tract in calcific AS for assessing the continuity equation. FSVR, however, also shows some significant limitations especially in patients with regional wall motion abnormalities and conduction defects. To overcome this problem, we developed a new index: the ejection fraction-velocity ratio (EFVR = ejection fraction/4 Vmax(2)), where percent ejection fraction and Vmax have been obtained with an apical echocardiographic approach. In 343 consecutive patients with AS, aortic valve area was measured by cardiac catheterization (Gorlin), whereas FSVR and EFVR were calculated by echo-Doppler examination performed within 24 hours. Mean valve area was 0.70 +/- 0.30 cm(2), mean EFVR was 0.78 +/- 0.41, and mean FSVR was 0.45 +/- 0.26. The linear correlation area-EFVR was highly significant (r = 0.88). Correlation valve area-FSVR was also significant (r = 0.82). EFVR allowed identification of patients with severe AS (area </=0.8 cm(2)) with good sensitivity (88%) and specificity (85%), whereas FSVR demonstrated sensitivity of 88% and specificity of 73%. Thus, the EFVR, a very simple and not time-consuming index, is strongly related to aortic valve area in patients with AS. It allows identification of patients with severe AS with good sensitivity and specificity (better than FSVR). The EFVR, taking into consideration both ejection fraction and transvalvular pressure gradient, may be very useful in the evaluation of patients with AS and left ventricular dysfunction.

Adult↗
PubMed2000

[Is a more efficient operative strategy feasible for the emergency management of the patient with acute chest pain?].

Patients with acute chest pain are a common problem and a difficult challenge for clinicians. In the United States more than 5 million patients are examined in the emergency department on a yearly basis, at a cost of 6 billion dollars. In the CHEPER registry the prevalence of patients with chest pain in the Emergency Department was 5.3%. Similarly, in 1997 at our institution the prevalence was 4.8%. Only 50% of the patients are subsequently found to have cardiac ischemia as the cause of their symptoms and 50-60% of them showed a non-diagnostic electrocardiogram (ECG). Twenty-five-50% of chest pain patients are not appropriately admitted to the hospital and despite this conservative approach, acute myocardial infarction is misdiagnosed up to 8% of patients with acute chest pain who are released from the emergency department without further evaluation, accounting for approximately 20% of emergency department malpractice in the United States. Important diagnostic information is covered by the patient's medical history, physical examination, and ECG, but often this approach is inadequate for a definitive diagnosis. Creatine kinase (CK) and CK isoenzyme--cardiac muscle subunit (CK-MB)--are traditionally obtained in the emergency department in patients admitted for suspected acute coronary syndrome. Mass measurements of CK-MB have improved sensitivity and specificity, and to date this is the gold standard test for diagnosis of acute myocardial infarction. CK-MB, however, is not a perfect marker because it is not totally cardiac specific and does not identify patients with unstable angina and minimal myocardial damage. There are no controlled clinical impact trials showing that these tests are effective in deciding whether to discharge or to appropriately admit the patient with suspected acute coronary syndrome. Relevant investigative interest has recently been focused on new markers for myocardial injury, including myoglobin, cardiac troponins T and I. Myoglobin, a sensitive but not specific marker for cardiac damage, increases earlier than CK-MB and cardiac troponins. It should be used early after symptom onset and in conjunction with a more specific marker of myocardial damage. Cardiac troponins T and I are highly specific markers for cardiac damage, rise parallel to CK-MB and remain elevated longer, up to 5 to 9 days. They are useful for detection of less severe degrees of myocardial injury, which may occur in several patients with unstable angina who are at higher risk of cardiac events. Recent studies suggest that cardiac troponins have good diagnostic performance and prognostic value in the heterogeneous population of patients seen in the Emergency Department with acute chest pain. Despite these promising data, several analytical and interpretative problems in the routine use of cardiac troponins must be solved. Incremental value of echocardiography in acute chest pain patients is still uncertain. Echocardiography can be recommended as an adjunctive test if readily available during acute chest pain or prolonged pain, especially in patients without previous myocardial infarction. Rest myocardial radionuclide imaging has been studied in the emergency department setting and although the overall diagnostic performance and prognostic value of sestamibi has been found to be promising, it is not suitable, in our country, for extensive clinical use. ECG exercise stress test in the emergency department population has been shown to be safe and it has a good negative predictive value for cardiac events. It should be recommended that any institution identify specific and shared protocol and strategies for management of patients with chest pain. These should include basal clinical evaluation, serial ECG and the use of specific and sensitive myocardial markers. Adjunctive tests, such as echocardiography, nuclear studies and stress tests should be employed when indicated taking into account local facilities.

Acute Disease↗
PubMed1999

Extracorporeal photochemotherapy does not suppress T- or B-cell responses to novel or recall antigens.

BACKGROUND: Extracorporeal photopheresis (ExP) is an effective therapy for several conditions including cutaneous T-cell lymphoma, scleroderma, and allograft rejection. Experimental animal models suggest that ExP may induce antigen-specific immunosuppression. OBJECTIVE: Our purpose was to determine the effect of photopheresis on humoral and cell-mediated immunity in human subjects. METHODS: Recall and primary immune responses of patients with scleroderma receiving monthly ExP treatments were assessed by delayed type hypersensitivity skin tests, T-cell proliferative responses after immunizations with tetanus toxoid and keyhole limpet hemocyanin, and serum antibody titers against common viral pathogens. RESULTS: After 6 months of ExP, viral antibody titers and delayed type hypersensitivity responses were not significantly different from baseline values in all 7 patients tested. T-cell responses to tetanus toxoid remained normal in 3 of 3 patients tested for a minimum of 6 months after booster immunization. Immunization with the protein antigen keyhole limpet hemocyanin after initiation of ExP therapy resulted in sustained T-cell proliferative responses up to 6 months in 3 of 3 patients. CONCLUSION: These results, along with the observation of no increased incidence of opportunistic infections or neoplasms, suggest that ExP is not broadly immunosuppressive and does not prevent primary responses to vaccination or other antigenic challenges.

Antibody Formation↗
PubMed1999

Retinoids synergize with interleukin-2 to augment IFN-gamma and interleukin-12 production by human peripheral blood mononuclear cells.

We have demonstrated previously that cells from both the skin and peripheral blood from patients with cutaneous T cell lymphoma (CTCL) have elevated levels of protein and mRNA for Th2 cytokines, interleukin-4 (IL-4) and IL-5, and depressed levels of Thl cytokines, IL-2 and interferon-gamma (IFN-gamma). Furthermore, IL-12 in vitro can restore IFN-gamma production by these patients' cells to near normal levels. Because retinoids exert therapeutic activity in CTCL and are potent modulators of growth and differentiation of hematopoietic cells, we investigated the role of retinoids in modulating Thl cytokine production. Peripheral blood mononuclear cells (PBMC) from normal donors and patients with CTCL were cultured with medium, IL-2, 13-cis-retinoic acid, all-trans-retinoic acid, acetretin or etretinate alone, or IL-2 plus the retinoids for 24 h, and levels of IFN-gamma were determined using ELISA. IL-2 or retinoids alone could induce low but significant levels of IFN-gamma. However, when IL-2 was cultured with each retinoid, a synergistic augmentation of IFN-gamma levels (4-fold to 90-fold) was observed except in the case of etretinate. All-trans-retinoic acid (ATRA) was the most potent IFN-y inducer. Similar studies performed using PBMC from CTCL patients indicated the IFN-gamma augmentation occurred but in a blunted manner. The IFN-y-inducing effect of ATRA and 13-cis-retinoic acid could be abrogated by addition of anti-IL-12 antibodies, suggesting that IL-12 plays a role in the synergistic upregulation of IFN-gamma. Using an IL-12 p40-specific radioimmunoassay (RIA), we confirmed the presence of IL-12 in IL-2 plus retinoid-treated culture supernatants. Purified monocytes cultured with IL-2 plus ATRA did not secrete IL-12. Only when monocytes were cocultured with lymphocytes was there an increase in IL-12 production, suggesting the involvement of a paracrine feedback loop requiring both monocytes and lymphocytes. These data suggest that retinoids can induce Th1 cytokines from normal and CTCL PBMC and that this induction may be mediated through IL-12 production.

Antigen-Antibody Reactions↗
PubMed1999

Clinical impact of local implementation of agreed guidelines for the management of patients with acute myocardial infarction.

OBJECTIVE: This study sought to assess the impact of local implementation of clinical practice guidelines on the pattern of care and outcome in patients admitted to the Coronary Care Unit (CCU) with acute myocardial infarction. BACKGROUND: Development of clinical practice guidelines is among the most popular of the methods intended to promote translation of results from clinical trials into routine care. However, very little is known about the actual impact on routine care of the clinical guidelines for managing patients with acute myocardial infarction. METHODS: We reviewed a prospectively collected cohort of consecutive patients discharged with a diagnosis of acute myocardial infarction from S. Maria degli Angeli, a large community-based hospital in northeast Italy. Eighty-six patients treated in 1996 (before guideline implementation) were compared with 70 patients treated in 1997 (after guideline implementation) with respect to patterns of use of guideline-directed pharmacotherapies for acute myocardial infarction, diagnostic testing, length of CCU stay and clinical outcome. RESULTS: The two groups were similar in male gender, age, infarct location and severity. Patients managed before guideline implementation were less likely to receive thrombolysis (36 vs 50%; p = 0.05), i.v. beta-blockers at admission (13 vs 31%; p = 0.002), oral beta-blockers at CCU discharge (45 vs 74%; p = 0.0003). When these were given, patients managed before guideline implementation received lower dosages of i.v. heparin, as manifested by a lower proportion of patients reaching adequate aPTT levels at 24 hours (14 vs 62%, p < 0.0001), and of oral beta-blockers (-50%, p < 0.0001), and higher dosage of aspirin (+100%, p < 0.0001). The time to mobilization (+1 day) and the length of CCU stay (+0.5 day) were longer in patients managed before guideline implementation (p < 0.0001). Incidence of major complications was similar between the two groups (19 vs 13%, respectively; p = ns). CONCLUSIONS: Patients with myocardial infarction managed after local implementation of clinical practice guidelines were more likely to receive evidence-based effective pharmacotherapies, and to have earlier mobilization and earlier discharge from CCU. This study strongly supports the role of local implementation of clinical practice guidelines to optimize management of patients with acute myocardial infarction.

Adrenergic beta-Antagonists↗
PubMed1997

Calcitonin gene-related peptide inhibits proliferation and antigen presentation by human peripheral blood mononuclear cells: effects on B7, interleukin 10, and interleukin 12.

CGRP is a neuropeptide that has previously been described to possess immunosuppressive activities. CGRP is released from peripheral nerves that, in the skin, are in close physical association with dendritic APC. We sought to investigate the mechanisms by which CGRP can inhibit immune responses by studying its effects on human peripheral blood mononuclear cells (PBMC). Using allogeneic monocytes as stimulator cells, CGRP could inhibit the proliferation of PBMC by 47% when CGRP was present for the duration of culture. Interestingly, when the stimulator monocytes were incubated with CGRP for 2 h prior to irradiation then washed, the observed inhibition increased to 85%, suggesting that CGRP was exerting a direct effect on the monocyte stimulator population. Finally, the recall response to tetanus toxoid (TT) by PBMC from individuals vaccinated with TT 14 d prior was inhibited by 25-50% in the presence of CGRP. Also, CGRP decreased the levels of B7.2 but not B7.1 on treated monocytes, and this inhibition could be abrogated by the addition of anti-IL-10 antibody, suggesting that the inhibition was mediated by an increase in IL-10 production. Moreover, increased IL-10 production was confirmed by ELISA. Both IL-12 p40 and IFN-gamma levels in CGRP-treated cultures were found to be decreased by approximately 30%. The decrease in IL-12 p40 levels could be reversed by addition of anti-IL-10. These data suggest that CGRP inhibits PBMC proliferation, in part, through the release of IL-10, which in turn can downregulate important co-stimulatory molecules and the cytokines IL-12 and IFN-gamma.

Antigen Presentation↗
PubMed1996

The potential therapeutic role of interleukin-12 in cutaneous T-cell lymphoma.

Cutaneous T-cell lymphoma (CTCL) is a lymphoproliferative disorder characterized by skin invasion of clonally derived malignant CD4+ lymphocytes that phenotypically resemble mature T-helper (Th) cells. Sezary syndrome (SzS) represents an advanced form of CTCL associated with generalized erythroderma and involvement of the peripheral blood by the malignant cell population. We have previously demonstrated aberrant cytokine production by peripheral blood mononuclear cells (PBMCs) in SzS characterized by increased IL-4 and deficient IL-2 and IFN-gamma production, as well as increased expression of mRNA for IL-4 and IL-5 within active skin lesions, indicating that the clonal T-cell population is likely derived from the T-helper type 2 (Th2) subset of helper T lymphocytes. Furthermore, a variety of immune abnormalities have been observed in association with SzS that have been attributed to the cytokine abnormalities. Because IL-12 is a potent inducer of IFN-gamma production and causes the activation of cytotoxic lymphocytes, we assessed the production of IL-12 by PBMCs from SzS patients, and whether IL-12 could alter the unfavorable cytokine balance typical of SzS and, thus, possibly lead to correction of immune defects. In this review, we present our data, which indicate that patients with SzS exhibit marked defects in monocyte production of IL-12 p70. Moreover, in vitro culture of PBMC from SzS patients with recombinant IL-12 leads to reconstitution of normal IFN-gamma production and markedly enhances cell-mediated cytotoxicity.

Cells, Cultured↗
PubMed1995

IL-12 reverses cytokine and immune abnormalities in Sezary syndrome.

Cutaneous T cell lymphoma is a lymphoproliferative disorder typically characterized by skin invasion of clonally derived malignant CD4+ lymphocytes that phenotypically resemble mature Th cells. Sezary syndrome (SzS) represents an advanced form of cutaneous T cell lymphoma associated with generalized erythroderma and involvement of the peripheral blood by the malignant cell population. We have previously demonstrated aberrant cytokine production by PBMC in SzS characterized by increased IL-4 and deficient IL-2 and IFN-gamma production, as well as increased expression of mRNA for IL-4 and IL-5 within active skin lesions, suggesting that the clonal T cell population is derived from the Th 2 subset of helper T lymphocytes. These findings have been associated with a constellation of immune abnormalities that have been attributed to the cytokine abnormalities. Because IL-12 is a potent inducer of IFN-gamma production, and causes the activation of cytotoxic lymphocytes, we examined the production of IL-12 by PBMC from SzS patients and whether IL-12 could alter the unfavorable cytokine balance typical of SzS and thus lead to correction of immune defects. Despite normal numbers of peripheral blood monocytes and normal TNF-alpha production, mean Staphyloccus aureus and LPS-induced IL-12 p40 and p70 production by SzS PBMC was significantly decreased compared with PBMC from normal controls. Mean IFN-gamma production by patient PBMC in response to PHA alone was depressed, but increased to levels comparable with normal after addition of 1 ng/ml IL-12. Pretreatment of PBMC for 24 h with IL-12, IFN-alpha, or both together resulted in a decrease in PHA-stimulated IL-4 production from a base line of 1818 pg/ml to 1520, 1350, and 1058 pg/ml, respectively. Lastly, culture of patient PBMC with IL-12 for 24 h also resulted in significant increases in NK activity against K562 cells. These results indicate that PBMC from patients with SzS manifest a defect in IL-12 production and that the cytokine abnormalities associated with SzS can be favorably altered by IL-12.

Cytokines↗
PubMed1995

Expression of interleukin-4 and interleukin-5 mRNA in developing cutaneous late-phase reactions.

The stimuli for the accumulation and activation of eosinophils, which are prominent components of IgE-mediated allergic late-phase reactions (LPRs), are not defined. Messenger RNA for interleukin-5 has been found in lymphocytes present in biopsy specimens of skin obtained during LPR 24 hours after antigen challenge. However, it is not known whether interleukin-5 is present to attract or activate the eosinophils that accumulate during the first 6 hours after antigen challenge when cutaneous LPRs are developing. Using reverse transcription-polymerase chain reaction, we have found mRNA for interleukin-5 in biopsy specimens obtained from control challenge sites nor in specimens from sites of antigen challenge of nonreactive subjects. We also found mRNA for interleukin-4 in these sites developing LPR. This pattern suggests that these cytokines may be important in eosinophil accumulation and activation during developing LPR. These findings are of considerable clinical relevance because the eosinophils in LPR are postulated to play major pathogenic roles in chronic allergic diseases.

Dermatitis, Atopic↗
PubMed1994

Th2 cytokine mRNA expression in skin in cutaneous T-cell lymphoma.

We have previously demonstrated that peripheral blood mononuclear cells from patients with Sézary syndrome, the leukemic form of cutaneous T-cell lymphoma which is accompanied by erythroderma and lymphadenopathy, have a Th2 cell cytokine [interleukin 4 (IL-4) and interleukin 5] production pattern. In this study, we extend these observations to demonstrate a correlation of the presence of a Th2 cytokine pattern with a malignant T-cell clone in different stages of cutaneous involvement among patients with cutaneous T-cell lymphoma (CTCL). Skin biopsies were obtained from 12 CTCL patients with various disease stages (three patch, three plaque, six tumor), three patients with parapsoriasis, four patients with inflammatory dermatoses, including two psoriasis and two lichen planus, and 12 normal controls. Total RNA was extracted, reverse transcribed, and PCR amplified with IL-2, IL-4, IL-5, interferon gamma (IFN-gamma), and beta-actin oligonucleotide primers. Although all skin specimens tested had detectable IL-2 and IFN-gamma mRNA, only specimens from patients with CTCL or parapsoriasis had demonstrable IL-4 and/or IL-5 mRNA. Specifically, IL-5 mRNA was detected in skin biopsies from five of six tumor-stage CTCL, two of three plaque-stage CTCL, one of three patch-stage CTCL, and 1 of 3 parapsoriasis patients, whereas IL-4 mRNA was demonstrated to be present in five of six tumor-stage, one of three plaque stage, none of three patch-stage CTCL, and none of three parapsoriasis patients. These results indicate that in all stages of cutaneous involvement of CTCL, encompassing patch stage through tumor stage, IL-4 and IL-5 mRNA is variably detectable. In tumor-stage skin lesions, typically characterized by a dense dermal infiltrate of malignant T cells, Th2 cytokine mRNA is virtually always detectable. The ability to detect Th2 cytokine mRNA in the skin of patients with CTCL supports our previous findings that the malignant T cells in CTCL possess a Th2-helper cell phenotype.

Base Sequence↗
PubMed1992

Extracorporeal photochemotherapy induces the production of tumor necrosis factor-alpha by monocytes: implications for the treatment of cutaneous T-cell lymphoma and systemic sclerosis.

Extracorporeal photopheresis (ExP) has been shown to be an efficacious and well-tolerated therapy in the treatment of cutaneous T-cell lymphoma (CTCL) and systemic sclerosis. However, the precise mechanisms of its action have not been defined. Because of a correlation between the development of fever in the early phase of treatment of CTCL and subsequent anti-tumor responses, we examined the production of the proinflammatory, pyrogenic cytokines tumor necrosis factor-alpha (TNF), IL-6, IL-1 alpha, and IL-1 beta before and after ExP. Monocytes were purified from peripheral blood specimens of normal volunteers (n = 4) or from peripheral blood specimens of CTCL (n = 6) or systemic sclerosis (n = 3) patients that were obtained immediately prior to ExP and also directly from the photopheresis unit after ExP, just prior to reinfusion into the patient. Monocytes were then cultured under various conditions for 16 h, after which the culture supernatants were collected and assayed for specific cytokine production. ExP induced a significant increase in the production of TNF (p less than 0.008) and IL-6 (p less than 0.05) as compared to non-ExP-treated cells, whereas no significant differences were observed in IL-1 alpha (p less than 0.5) and IL-1 beta (p less than 0.2) production following ExP. Exposure of monocyte cultures to IFN-gamma (100 U/mL) either before or after ExP further enhanced TNF production by 4 to 28 times. In contrast, incubation with IFN-alpha (100 U/mL) had no significant effect on TNF production. Addition of TNF (500 U/ml) to monocyte cultures obtained prior to ExP resulted in a slight but insignificant increase in TNF production in 2 of 10 cases. However, when monocytes obtained prior to ExP were incubated with 8-methoxypsoralen (8-MOP, 100 ng/ml), exposed to ultraviolet light A (UVA, 2J/cm2), washed, and then incubated with TNF, a significant increase (p less than 0.01) in TNF production was observed in 8 of 10 cases, suggesting that the combination of 8-MOP and UVA may sensitize cells to TNF. Based on studies of endotoxin (LPS)-stimulated production of TNF by monocytes, levels of endotoxin in culture reagents or photopheresis equipment could not account for the increased production of TNF following treatment by ExP. Increased TNF production as a result of ExP may have important implications for treating both CTCL and systemic sclerosis because, in the case of CTCL, it could mediate numerous anti-tumor effects, whereas, in the case of systemic sclerosis, it could suppress collagen synthesis and induce collagenase production.

Endotoxins↗
PubMed1992

Aberrant cytokine production by Sezary syndrome patients: cytokine secretion pattern resembles murine Th2 cells.

Sezary syndrome (SzS), the leukemic stage of cutaneous T-cell lymphoma (CTCL), is typically a CD4+ T-cell lympho-proliferative disease characterized by numerous immunologic abnormalities, including decreased T-cell responses to antigens and mitogens, decreased natural killer and lymphocyte-activated killer cell activities, eosinophilia, and increased levels of immunoglobulins, particularly IgE and IgA. Because this constellation of abnormalities is reminiscent of the pleiotropic in vitro activities of IL-4 and IL-5, we examined the possibility that malignant T cells in SzS may be producing increased amounts of IL-4 with a concomitant decrease in IL-2 and IFN-gamma production. Such a cytokine secretion pattern would be similar to that produced by murine Th2 cells. Serum IL-4 enzyme-linked immunosorbent assay measurements revealed that 33% of SzS patients (n = 21) had levels of IL-4 significantly higher (mean, 7.2 pg/ml; range, 0-48, p less than 0.05) than normal controls (mean, 1.59; range, 0-3.1). Although the majority of tested patients had elevated serum IgE, no direct correlation between serum IL-4 levels and serum IgE levels was observed. Peripheral blood mononuclear cells (PBMC) isolated from SzS patients and stimulated with phytohemagglutinin (PHA) produced significantly higher levels of interleukin (IL)-4 and significantly lower levels of IL-2 and interferon (IFN)-gamma than did PBMC from normal controls (p less than 0.02, p less than 0.05, and p less than 0.02, respectively). PBMC from SzS patients in remission produced IL-4 and IL-2 levels similar to that of the normal controls. To determine if IFN-gamma could inhibit the increased IL-4 production by PHA-stimulated PBMC from SzS patients, IFN-gamma was added to culture at 0, 24, or 48 h prior to the addition of PHA. Significant decreases in IL-4 production were seen only in cultures incubated with IFN-gamma for 24 and 48 h prior to the addition of PHA. IL-2 levels were not affected by IFN-gamma incubation. The increased IL-4 and decreased IL-2 and IFN-gamma production by PBMC from SzS patients suggests that Sezary cells have a cytokine profile similar to murine Th2 cells. Moreover, this cytokine secretion pattern may play an integral role in the immunopathogenesis of advanced CTCL. The results also suggest that IFN-gamma be a useful component in the spectrum of therapeutic approaches to SzS.

Animals↗