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1.
AIDS Patient Care STDS ; 15(7): 363-71, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11483163

ABSTRACT

HIV-associated nephropathy (HIVAN) is the most common cause of renal failure in patients infected with type 1 human immunodeficiency virus (HIV-1). The renal prognosis for HIVAN is poor and is typically associated with rapid progression to renal death. We report a patient with biopsy-proven HIVAN who was successfully treated with corticosteroids and review the currently available evidence supporting the specific treatments of this condition. A 34-year-old African-American male with a 2-year history of uncomplicated HIV disease developed progressive azotemia despite treatment with highly active antiretroviral therapy (HAART). He was treated with an uncomplicated 4-month course of prednisone, which improved his serum creatinine from 2.9 to 1.9 mg/dl and decreased his degree of proteinuria from 8 to 2.1 g/day. Two years post-steroid treatment his renal function remains stable. Increasing evidence supports that both ACE inhibitors and HAART are effective in preventing and in some cases of reversing HIVAN induced renal failure. In selected patients who progress despite these measures, a limited course of corticosteroid may achieve long-standing disease remissions. In general, with adequate supervision, corticosteroid therapy appears to be well tolerated and has an acceptable side effect profile. Although persuasive in view of the abysmal natural history of HIVAN, the currently available studies are subject to major methodological limitations. Appropriate randomized controlled trials are urgently required in order to further examine the efficacy, optimal timing, and potential side effects of these treatments.


Subject(s)
AIDS-Associated Nephropathy/drug therapy , Antiretroviral Therapy, Highly Active , Glucocorticoids/therapeutic use , Prednisone/therapeutic use , AIDS-Associated Nephropathy/pathology , Adult , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , HIV-1 , Humans , Male
2.
Kidney Int ; 58(3): 1253-60, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10972688

ABSTRACT

BACKGROUND: Human immunodeficiency virus-associated nephropathy (HIVAN) results in rapidly progressive azotemia. The effectiveness and safety of corticosteroids in the treatment of HIVAN, however, remains controversial. METHODS: We conducted a retrospective cohort study of patients with biopsy-proven HIVAN and progressive azotemia who were eligible for corticosteroid treatment and who had no clinical or histologic evidence of an alternative cause of acute renal failure. Selected patients were treated with 60 mg of prednisone for one month, followed by a several-month taper. RESULTS: Twenty-one eligible patients were identified. Thirteen subjects had received corticosteroid treatment, whereas eight had not. The mean serum creatinine was 6.2 and 6.8 mg/dL, respectively (P > 0.05). The relative risk (95% CI) for progressive azotemia with corticosteroid treatment at three months was 0.20 (0.05, 0.76, P < 0.05). This association remained significant despite adjustment in separate logistical regression analyses for baseline creatinine, 24-hour proteinuria, CD4 count, history of intravenous drug use, hepatitis B, and hepatitis C. In an additional logistic regression model, using backward stepwise selection of the previously mentioned covariates, only corticosteroid treatment (P = 0.02) and baseline serum creatinine (P = 0.10) were retained within the model. In the corticosteroid-treated group, the mean level of proteinuria decreased by 5.5 g/24 hour (P = 0.01). On long-term follow-up, there was no significant difference in the incidence of hospitalizations (1 per 2.1 vs. 1 per 2.3 patient months) or of serious infections (1 per 2.6 vs. 1 per 2.3 patient months), but there was a significantly longer duration of hospitalization in the corticosteroid-treated group (3.2 vs. 2 days per patient month). At six months, only one of the non-corticosteroid-treated patients but seven of the corticosteroid-treated group continued to have independent renal function (P = 0.06). Three of the corticosteroid-treated group continued to have independent function at two years of follow-up. CONCLUSION: A limited course of corticosteroid therapy in selected patients was beneficial and safe. Further research is required for the role of corticosteroids in the treatment of HIVAN.


Subject(s)
AIDS-Associated Nephropathy/drug therapy , Adrenal Cortex Hormones/therapeutic use , Kidney Failure, Chronic/drug therapy , Kidney Failure, Chronic/virology , AIDS-Related Opportunistic Infections/epidemiology , Adult , Cohort Studies , Disease Progression , Female , Follow-Up Studies , Humans , Incidence , Kidney/physiology , Length of Stay/statistics & numerical data , Male , Middle Aged , Proteinuria/drug therapy , Proteinuria/virology , Renal Dialysis , Retrospective Studies , Treatment Outcome , Uremia/drug therapy , Uremia/virology
3.
J Clin Pharmacol ; 40(2): 115-23, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10664916

ABSTRACT

A remission in nephrotic proteinuria with steroid treatment appears to favorably alter the natural history of focal segmental glomerulosclerosis (FSGS). It is not known why some patients have a favorable response to steroid treatment whereas others do not. Considering the possibility that differences in the pharmacodynamic responsiveness to steroids among patients might be one factor, the authors examined the relationship between the pretreatment suppressive effect of steroids on lymphocyte proliferation (% inhibition) in vitro and the short- and intermediate-term responses of creatinine clearance (Clcr) and/or nephrotic proteinuria (urine protein/creatinine ratio = Up/c) in 13 patients with FSGS. There were significant correlations between % inhibition and the changes in Clcr at 3 (r = 0.92, p < 0.001) and 6 (r = 0.86, p < 0.01) months and the changes in Up/c at 3 months (r = -0.74, p = 0.02). Thus, the greater the pretreatment lymphocyte steroid sensitivity, the greater the increase in Clcr or decrease in Up/c. The changes in these parameters could not be accounted for on the basis of steroid dose or histopathology. The in vitro sensitivity of FSGS patients' lymphocytes to steroids may be of value in anticipating their clinical response to treatment.


Subject(s)
Glomerulosclerosis, Focal Segmental/drug therapy , Glucocorticoids/therapeutic use , Lymphocyte Activation/drug effects , Adult , Aged , Creatinine/pharmacokinetics , Female , Glomerulosclerosis, Focal Segmental/immunology , Humans , Male , Middle Aged , Proteinuria/drug therapy
4.
J Clin Pharmacol ; 39(8): 794-9, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10434230

ABSTRACT

Pentoxifylline, a nonselective phosphodiesterase inhibitor, has immunomodulatory activity in vitro and in vivo and potentiates the suppressive effects of glucocorticoids and cyclosporine on lymphocyte proliferation in vitro. Since phosphodiesterase isotypes 3 and 4 predominate in lymphocytes, the authors measured the suppressive effect of rolipram alone and in combination with low concentrations of methylprednisolone and calcineurin enzyme inhibitors, compared to that of pentoxifylline on mitogen-stimulated lymphocyte proliferation. The percent inhibition of 3H-thymidine incorporation by both 10(-5) and 10(-8) mol/L concentrations of rolipram were significantly greater than that by both 10(-4) mol/L pentoxifylline and 10(-8) mol/L methylprednisolone. The percent inhibition by the combination of 10(-5), but not 10(-6), mol/L rolipram and methylprednisolone was significantly greater than that by 10(-4) mol/L pentoxifylline and methylprednisolone. Potentiation of the suppressive effects of cyclosporine and tacrolimus by rolipram was less consistent. Measurement of cell culture supernatant concentrations of interferon gamma and interleukin-10 indicate that one of the mechanisms underlying the immunosuppressive activity of rolipram is a significantly disproportionate inhibition of the proinflammatory cytokine, interferon gamma.


Subject(s)
Immunosuppressive Agents/pharmacology , Lymphocytes/drug effects , Phosphodiesterase Inhibitors/pharmacology , Pyrrolidinones/pharmacology , Adult , Aged , Cell Division/drug effects , Cohort Studies , Cyclosporine/pharmacology , Dose-Response Relationship, Drug , Female , Humans , Interferon-gamma/biosynthesis , Interferon-gamma/drug effects , Interleukin-10/biosynthesis , Leukocytes, Mononuclear/cytology , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Lymphocytes/cytology , Lymphocytes/metabolism , Male , Methylprednisolone/pharmacology , Middle Aged , Pentoxifylline/pharmacology , Rolipram , Tacrolimus/pharmacology , Thymidine/metabolism , Tritium
6.
J Clin Pharmacol ; 39(2): 119-24, 1999 Feb.
Article in English | MEDLINE | ID: mdl-11563402

ABSTRACT

To evaluate molecular mechanisms that might account for the heterogeneity in the in vitro responsiveness of individual subjects' peripheral blood mononuclear cells (PBMC) to immunosuppressive drugs, the authors quantitated in normal human cells the suppressive effects of the glucocorticoids prednisolone and methylprednisolone and of cyclosporine on interleukin-2 (IL-2) mRNA expression and IL-2 production, as well as the stimulatory effect of these drugs on IkappaBalpha mRNA expression. As expected, cyclosporine was significantly more suppressive than either glucocorticoid of IL-2 mRNA expression and IL-2 production by mitogen-stimulated PBMC, with variable degrees of inhibition in cells from individual subjects. The authors confirmed in human PBMC the stimulation of IkappaBalphamRNA expression by the glucocorticoid reported by others in HeLa and transfected Jurkat cell lines. In addition, the authors observed a stimulatory effect on IkappaBalpha mRNA expression by cyclosporine as well in 8 of 10 PBMC preparations studied, suggesting a possible role of calcineurin in the regulation of IkappaBalpha production. Interindividual variability in the intracellular mechanisms of action, possibly based on molecular polymorphisms, might be one factor contributing to differences among patients in their clinical responses to treatment with such drugs.


Subject(s)
Cyclosporine/pharmacology , DNA-Binding Proteins/biosynthesis , Glucocorticoids/pharmacology , I-kappa B Proteins , Immunosuppressive Agents/pharmacology , Interleukin-2/biosynthesis , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , RNA, Messenger/biosynthesis , Cells, Cultured , DNA-Binding Proteins/genetics , Humans , Interleukin-2/genetics , NF-KappaB Inhibitor alpha
7.
J Clin Pharmacol ; 39(2): 125-30, 1999 Feb.
Article in English | MEDLINE | ID: mdl-11563403

ABSTRACT

Methylprednisolone has been found to be significantly more suppressive than prednisolone (the pharmacologically active metabolite of prednisone) of mitogen-stimulated human lymphocyte proliferation. In this study, peripheral blood mononuclear cells (PBMC) from end stage renal disease patients were cultured with phytohemagglutinin (PHA) alone and with methylprednisolone and prednisolone individually, as well as each glucocorticoid (10(-7) mol/L) in combination with 300 ng/ml cyclosporine, 10 ng/ml tacrolimus, 25 microg/ml pentoxifylline, and 10(-7) mol/L mycophenolic acid. Under each experimental condition, the mean +/- SD % inhibition of PHA-stimulated 3H-thymidine incorporation was significantly greater with methylprednisolone than with prednisolone: methylprednisolone 55 +/- 17 versus prednisolone 28 +/- 14, p < 0.001; methylprednisolone + cyclosporine 76 +/- 18 versus prednisolone + cyclosporine 52 +/- 18, p < 0.001; methylprednisolone + tacrolimus 74 +/- 18 versus prednisolone + tacrolimus 50 +/- 20, p = 0.001; methylprednisolone + mycophenolic acid 69 +/- 14 versus prednisolone + mycophenolic acid 46 +/- 15, p < 0.001. These results confirm and extend previous observations and suggest that methylprednisolone might be more effective than prednisone in treatment protocols used to suppress allograft rejection.


Subject(s)
Glucocorticoids/pharmacology , Immunosuppressive Agents/pharmacology , Lymphocytes/drug effects , Methylprednisolone/pharmacology , Prednisolone/pharmacology , Cells, Cultured , Cyclosporine/pharmacology , Cyclosporine/therapeutic use , Drug Combinations , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/therapeutic use , Glucocorticoids/therapeutic use , Humans , Immunosuppressive Agents/therapeutic use , Kidney Failure, Chronic/blood , Kidney Failure, Chronic/drug therapy , Lymphocytes/metabolism , Methylprednisolone/therapeutic use , Mycophenolic Acid/pharmacology , Mycophenolic Acid/therapeutic use , Pentoxifylline/pharmacology , Pentoxifylline/therapeutic use , Prednisolone/therapeutic use , Tacrolimus/pharmacology , Tacrolimus/therapeutic use
8.
J Immunoassay ; 19(2-3): 129-43, 1998.
Article in English | MEDLINE | ID: mdl-9682128

ABSTRACT

The proliferative response of human lymphocytes to stimuli such as foreign histocompatibility antigens or mitogens is generally assessed by measuring the amount of tritiated thymidine which the cells incorporated in culture. In this paper, the possibility of assessing lymphocyte proliferation and viability by an empirical assay, using measurement of light absorbance on a ELISA reader in the yellow wave length (450 nm/air-550 nm/air), has been studied. The correlation of these measurements with a colormetric viability assay using MTS/PMS, with tritiated thymidine incorporation and with trypan blue exclusion viability counting, was determined. The results showed that the light absorbance assay correlated well with cell proliferation during 48-120 hours culture period and with cell viability after a 72 hour period. The MTS/PMS colormetric assay as well as trypan blue exclusion cell counting confirmed that the light absorbance assay was not merely caused by dead cells. This data confirm that the light absorbance assay is sufficiently sensitive to low levels of proliferation to allow detection of such responses at least as effectively as thymidine incorporation. The light absorbance assay procedure avoids the expense, time and hazards associated with scintillation counting, and is simple to perform without the necessity for reagents and preparative steps required by other assays.


Subject(s)
Lymphocyte Activation , Adolescent , Adult , Cell Division , Cell Survival , Colorimetry , Enzyme-Linked Immunosorbent Assay , Female , Humans , Hydrogen-Ion Concentration , Indicators and Reagents , Light , Lymphocyte Culture Test, Mixed , Male , Middle Aged , Spectrophotometry , Thymidine/metabolism
9.
J Clin Pharmacol ; 38(6): 561-6, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9650547

ABSTRACT

Pentoxifylline, which has immunomodulatory effects in addition to its better known rheologic effects, might potentiate the effectiveness of traditional immunosuppressive drugs. We therefore studied the suppressive effect of pentoxifylline in combination with clinically relevant concentrations of prednisolone, methylprednisolone, cyclosporine, tacrolimus, rapamycin, and mycophenolic acid on mitogen-stimulated lymphocytes from 29 patients with glomerular diseases. Inhibition of lymphocyte proliferation obtained with 10(-7) and 10(-8) mol/L concentrations of the glucocorticoids and with 300 ng/mL cyclosporine was significantly increased when each was combined with 5, 25, or 50 microg/mL of pentoxifylline. The additive inhibitory effect of pentoxifylline in combination with 10(-7) mol/L glucocorticoids was inversely proportional to the inhibitory effect of the 10(-7) mol/L concentration of glucocorticoid alone, suggesting that the less sensitive the patient's cells, the greater the potentiation by pentoxifylline. The greatest degree of potentiation by pentoxifylline occurred when combined with the lower (10(-8) mol/L) concentration of glucocorticoids. Pentoxifylline also significantly increased lymphocyte suppression in combination with 150 and 300 ng/mL concentrations of cyclosporine, 5 ng/mL of tacrolimus, 2.5 x 10(-7) mol/L mycophenolic acid, and 10 ng/mL of rapamycin. These in vitro results suggest that pentoxifylline might have steroid-sparing effects and contribute to improved clinical outcomes from immunosuppressive treatment of renal diseases.


Subject(s)
Glucocorticoids/pharmacology , Immunosuppressive Agents/pharmacology , Lymphocytes/drug effects , Pentoxifylline/pharmacology , Adult , Aged , Analysis of Variance , Cyclosporine/pharmacology , Drug Synergism , Female , Humans , Lymphocytes/immunology , Male , Methylprednisolone/pharmacology , Middle Aged , Prednisolone/pharmacology
11.
Am J Kidney Dis ; 31(2): 213-7, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9469489

ABSTRACT

Eight patients with resistant and/or relapsing nephrotic syndrome or renal insufficiency were empirically treated with mycophenolate mofetil (MMF). The underlying glomerular diseases were membranous nephropathy (N = 3), minimal change disease (n = 2), focal segmental glomerulosclerosis (n = 1), and lupus nephritis (N = 2). Treatment with MMF 0.75 to 1.0 g twice daily, either as monotherapy or in combination with low-dose steroid treatment, resulted in substantial reductions in proteinuria or stabilization of serum creatinine. In relapsing patients following withdrawal from cyclosporin A, MMF achieved suppression of proteinuria equivalent to or better than that which occurred during cyclosporin A treatment. Steroids were successfully withdrawn in each of the non-lupus patients. MMF was well tolerated with no evidence of hematologic, hepatic, or other toxicity. These clinical anecdotes demonstrate the short-term clinical efficacy of MMF treatment. In addition, they suggest that MMF may have major steroid-sparing effects and might represent an alternative to cyclosporin A in appropriate patients.


Subject(s)
Glomerulonephritis/drug therapy , Immunosuppressive Agents/therapeutic use , Mycophenolic Acid/analogs & derivatives , Nephrosis/drug therapy , Adult , Aged , Female , Glomerulonephritis, Membranous/drug therapy , Glomerulosclerosis, Focal Segmental/drug therapy , Humans , Lupus Nephritis/drug therapy , Male , Mycophenolic Acid/therapeutic use , Nephrosis, Lipoid/drug therapy
12.
Cytokine ; 9(8): 624-8, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9245491

ABSTRACT

Previous studies have shown interindividual heterogeneity in the suppressive effects of glucocorticoids and cyclosporine (CsA) on the proliferation responses of dialysis patients' peripheral blood mononuclear cells (PBMC). In addition, methylprednisolone (MP) was shown to be significantly more suppressive than prednisolone (P), and PBMC from patients on peritoneal dialysis (PD) were found to be more sensitive to both glucocorticoids than those from patients on haemodialysis (HD). In order to begin to explore the cellular mechanism(s) underlying these observations, the differential suppressive effects of these drugs on lymphocyte interleukin 2 receptor (IL-2R) expression by mitogen-stimulated PBMC from 23 PD and 30 HD were determined. The mean+/-SD concentrations (ng/ml) of steroid causing 50% inhibition (IC50) of cell proliferation was significantly lower for PD than HD PBMC with both P (94+/-93 vs 148+/-105, P<0.05) and MP (21+/-25 vs 35+/-31, P<0.05). MP was significantly (P<0.001) more suppressive than P of IL-2R expression in both PD and HD. PD IL-2R expression was significantly (P<0.05) more suppressed by CsA alone and by 400 ng/ml CsA+10(-7) MP than was HD IL-2R expression. CsA+10(-7) M MP was significantly (P<0.001) more suppressive of IL-2R expression than the other drugs, alone or in combination, in both groups of patients. In conclusion, these results support the notion that at least one mechanism underlying the significantly greater efficacy of MP compared to P in suppressing PBMC proliferation is its significantly greater suppression of lymphocyte IL-2R expression, either alone or in combination with CsA. Thus, use of MP following allograft transplantation may result in more effective immunosuppression for many recipients.


Subject(s)
Cyclosporine/pharmacology , Glucocorticoids/pharmacology , Immunosuppressive Agents/pharmacology , Lymphocytes/drug effects , Methylprednisolone/pharmacology , Prednisolone/pharmacology , Receptors, Interleukin-2/biosynthesis , Renal Dialysis , Cells, Cultured , Humans , Leukocytes, Mononuclear/cytology , Leukocytes, Mononuclear/drug effects , Lymphocytes/cytology , Lymphocytes/metabolism , Mitogens/pharmacology , Phytohemagglutinins/pharmacology
13.
ASAIO J ; 43(1): 31-4, 1997.
Article in English | MEDLINE | ID: mdl-9116350

ABSTRACT

Acute allograft rejection remains a problem after renal transplantation, even in the cyclosporine era. Interindividual differences in the pharmacodynamic responses of the immune system to immunosuppressive agents might contribute to the vulnerability of some patients to rejection. Having previously demonstrated decreased sensitivity of hemodialysis patients' lymphocytes to glucocorticoid suppression of mitogen induced proliferation, the authors undertook a separate study to assess the suppressive effect of glucocorticoids on lymphocyte responsiveness to allogeneic cells and mitogenic stimulation. Lymphocytes were isolated from 32 hemodialysis patients in clinically stable condition for studies in both phytohemagglutinin (PHA) stimulated cultures and in one-way mixed lymphocyte (MLR) cultures. From the concentration-response relationships derived from stimulated cultures with 10 (-6), 10(-7), and 10(-8) M concentrations of prednisolone and methylprednisolone, the concentration of steroid required to achieve 50% inhibition (IC50) of lymphocyte proliferation was determined. A broad range of IC50 values was found in both PHA and MLR cultures, but within individual patients, the IC50 values for both steroids correlated significantly between PHA and MLR cultures. The inhibitory effect of methylprednisolone was significantly greater than that of prednisolone in both PHA and MLR cultures. These results demonstrate a heterogeneity of pharmacodynamic responsiveness to prednisolone and methylprednisolone that is consistent with individuals in two in vitro models of cellular immune response. Pretransplant evaluation by these methods may help identify patients at risk of suboptimal immunosuppression and assist in selecting the steroid component of the immunosuppressive regimen.


Subject(s)
Glucocorticoids/pharmacology , Immunosuppressive Agents/pharmacology , Lymphocyte Activation/drug effects , Renal Dialysis , Adult , Aged , Aged, 80 and over , Cells, Cultured , Female , Humans , Lymphocyte Culture Test, Mixed , Male , Middle Aged
14.
Am J Kidney Dis ; 28(4): 618-21, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8840956

ABSTRACT

A 43-year-old man with rapidly evolving renal failure from biopsy-proven human immunodeficiency virus (HIV)-associated nephropathy (HIVAN) and superimposed thrombotic microangiopathic changes was treated with prednisone. His serum creatinine decreased from 7.5 to 3.9 mg/dL, and the 24-hour protein excretion decreased from 15.7 to 6.1 g over 6 to 8 weeks. As the prednisone was tapered, however, the creatinine began to increase, and a repeat biopsy was done to assist with therapeutic decisions. The major differences from the pretreatment biopsy were marked reductions in interstitial lymphocytes and macrophages and absence of thrombotic microangiopathic lesions. This is the first report comparing pretreatment and posttreatment renal biopsy specimens and the findings provide some insight into the means by which prednisone exerts its beneficial clinical effects acutely on this disease.


Subject(s)
AIDS-Associated Nephropathy/drug therapy , Glucocorticoids/therapeutic use , Prednisone/therapeutic use , AIDS-Associated Nephropathy/blood , AIDS-Associated Nephropathy/pathology , Adult , Biopsy , Creatinine/blood , Humans , Kidney/pathology , Male
15.
Cytokine ; 8(10): 804-8, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8980883

ABSTRACT

IFN-gamma is a potent pro-inflammatory cytokine involved in the immunologic rejection of transplanted organs. Having previously demonstrated differential suppressive effects of methylprednisolone (MP), prednisolone (P) and cyclosporine (CsA) on dialysis patients' lymphocyte proliferative responses to phytohaemagglutinin (PHA), we studied the effects of these drugs on dialysis patients' lymphocyte IFN-gamma production during mitogenic and allogeneic (MLR) stimulation. The mean +/- SEM 50% inhibitory concentration (ng/ml) on cell proliferation was significantly lower for MP than P in PHA-stimulated haemodialysis (HD) patients' (35 +/- 7 vs 152 +/- 25, P < 0.001) and peritoneal dialysis (PD) patients' (35 +/- 11 vs 134 +/- 33, P = 0.001) cultures and in HD patients' MLR cultures (15 +/- 3 vs 48 +/- 9, P < 0.001). The mean +/- SEM fractional responses (PHA or MLR + drug/PHA or MLR) in culture supernatant IFN-gamma concentrations were significantly lower with 10(-7) M concentrations of MP than P in HD (0.19 +/- 0.05 vs 0.31 +/- 0.06, P = 0.01) and PD (0.30 +/- 0.11 vs 0.46 +/- 0.11, P < 0.05) PHA cultures and in HD MLR cultures (0.15 +/- 0.04 vs 0.28 +/- 0.07, P = 0.01). CsA (400 ng/ml) alone not only caused less than 50% inhibition of IFN-gamma production in 15/27 HD PHA, 6/14 PD PHA and 4/13 HD MLR cultures, but actually stimulated it in 9 HD and 5 PD PHA cultures. The results suggest that: (1) MP has greater immunosuppressive potential than P for renal transplant recipients; (2) the stimulation of IFN-gamma by CsA in some patients could be harmful in patients with initial allograft dysfunction; and (3) pre-transplant in-vitro assessment of recipients' PBMC responsiveness to glucocorticoids and CsA may help individualize the post-transplant immunosuppressive regimen.


Subject(s)
Cyclosporine/pharmacology , Interferon-gamma/biosynthesis , Methylprednisolone/pharmacology , Prednisolone/pharmacology , Renal Dialysis , Enzyme-Linked Immunosorbent Assay , Humans , Interferon-gamma/blood , Kidney Failure, Chronic/blood , Kidney Failure, Chronic/therapy , Lymphocytes/drug effects , Lymphocytes/metabolism , Phytohemagglutinins/pharmacology , Transplantation, Homologous
16.
J Clin Pharmacol ; 36(10): 931-7, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8930780

ABSTRACT

Although glucocorticoids and cyclosporine are frequently used to treat patients with various types of glomerulopathy, clinical responses to treatment vary considerably. Considerable interindividual heterogeneity in the suppressive effects of glucocorticoids on lymphocyte proliferation in vitro has been previously reported, suggesting that differences in the pharmacodynamic responsiveness of the immune system to these agents might be an important determinant of how well an individual patient responds to treatment. It also has been shown that methylprednisolone is significantly more suppressive than prednisolone. To identify cellular mechanisms by which these drugs act, a study of the suppressive effects of prednisolone, methylprednisolone, and cyclosporine on lymphocyte proliferation and the expression of the cell surface receptor for interleukin-2 (IL-2R) was conducted using phytohemagglutin-stimulated peripheral blood mononuclear cells (PBMCs) from 13 patients with glomerulopathy and 12 control subjects. Heterogeneity among individuals in both parameters of lymphocyte responsiveness to these drugs was again found, and the significantly greater suppressive effect of methylprednisolone was confirmed for both proliferation and IL-2R expression in patients and control subjects. Cyclosporine alone was moderately suppressive. For most individuals, the greatest degree of suppression occurred when cells were exposed to both cyclosporine and glucocorticoid. Further studies are being conducted to determine whether pretreatment assessment of in vitro lymphocyte responsiveness has any predictive value regarding therapeutic efficacy of each drug in individual patients and to identify of those patients likely to require a more intensive or multidrug immunosuppressive regimen.


Subject(s)
Cyclosporine/pharmacology , Glucocorticoids/pharmacology , Lymphocyte Activation/drug effects , Receptors, Interleukin-2/drug effects , Adult , Aged , Case-Control Studies , Cells, Cultured , Female , Glomerulonephritis/immunology , Humans , Male , Middle Aged
17.
J Clin Pharmacol ; 36(8): 707-14, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8877674

ABSTRACT

The reason why some patients with glomerular diseases respond to steroid treatment and others do not remains obscure, and it is not possible to prospectively evaluate the probability of response in individual patients. One factor that might contribute to the clinical response to treatment could be the relative sensitivity of a patient's immune system to the suppressive effects of steroids or other immunosuppressive agents. To evaluate this possibility, phytohemagglutinin (PHA)-stimulated peripheral blood mononuclear cells (PBMC) from 16 patients with various biopsy-proven glomerulopathies were cultured with prednisolone or methylprednisolone in final concentrations of 10(-5) to 10(-8) mol/L. From the dose-response curves, the concentration of steroid required to cause 50% inhibition (IC50) of the PHA-induced proliferative response was determined. The PBMC from 10 patients also were cultured with 400 ng/mL cyclosporine both alone and with 10(-7) mol/L steroid, and the inhibitory effects were calculated. There was considerable heterogeneity in the sensitivities of individual patients to steroid inhibition, and the mean +/- SEM IC50 was significantly lower for methylprednisolone than for prednisolone. Cyclosporine caused 50% or greater inhibition in 6 of the 10 patients but had < 10% inhibitory effect in 2 patients. In most patients studied, cyclosporine plus steroid was significantly more inhibitory than cyclosporine alone, but the combination was usually no more effective than 10(-7) mol/L methylprednisolone alone. These results are consistent with the hypothesis that differences in the sensitivity of individual patient's immune systems to the immunosuppressive effects of steroids and cyclosporine might contribute to differences in their clinical responsiveness to treatment.


Subject(s)
Cyclosporine/pharmacology , Glomerulonephritis/blood , Glucocorticoids/pharmacology , Immunosuppressive Agents/pharmacology , Lymphocytes/drug effects , Adult , Aged , Cells, Cultured , Drug Interactions , Female , Glomerulonephritis/drug therapy , Glomerulonephritis/immunology , Humans , Lymphocyte Activation/drug effects , Male , Methylprednisolone/pharmacology , Middle Aged , Prednisolone/pharmacology
19.
Perit Dial Int ; 16(4): 406-11, 1996.
Article in English | MEDLINE | ID: mdl-8863335

ABSTRACT

OBJECTIVES: To evaluate in vitro glucocorticoid responsiveness of phytohemagglutinin (PHA)-stimulated lymphocytes from peritoneal dialysis (PD) patients compared to hemodialysis (HD) patients. DESIGN: Cross-sectional study of prevalent PD and HD patients and concurrent control subjects. SETTING: Urban outpatient dialysis unit. PATIENTS: 20 HD, 14 PD, and 20 control subjects. MEASUREMENTS: Using standard lymphocyte culture techniques, the concentration of prednisolone (P) and methylprednisolone (MP) required to cause 50% inhibition (IC50) of the proliferative response to phytohemagglutinin (PHA) was determined from dose-response curves. RESULTS: There was considerable heterogeneity in the sensitivities of individual patients' PBMC to glucocorticoid inhibition, especially those of HD patients' cells to P. The mean +/- SD IC50 for MP was significantly (p < or = 0.001) lower than that for P in each cohort: PD 11 +/- 5 vs. 34 +/- 18 ng/mL; HD 22 +/- 14 vs. 89 +/- 43 ng/mL; control subjects 14 +/- 11 vs. 55 +/- 56 ng/mL. Interestingly, the IC50 for both P and MP was significantly higher in HD than in either PD or controls (ANOVA, P: F = 6.56, p = 0.003; MP: F = 3.77, p = 0.03), indicating decreased sensitivity of HD lymphocytes to both drugs. There were no significant differences in mean IC50 values for either P or MP between PD and controls. No correlations were found between IC50 for either P or MP and patient age, gender, duration of dialysis, serum creatinine, serum albumin, or parathyroid hormone level. CONCLUSIONS: In vitro glucocorticoid responsiveness of dialysis patients' lymphocytes appears to be influenced by dialysis modality, but the factor(s) involved remains to be determined. The greater sensitivity of PD lymphocytes to both P and MP might result in better immunosuppression and less severe rejection after renal transplantation. MP may be particularly advantageous following renal transplantation for any patient manifesting relative or absolute in vitro resistance to P.


Subject(s)
Glucocorticoids/pharmacology , Lymphocyte Activation/drug effects , Methylprednisolone/pharmacology , Peritoneal Dialysis , Prednisolone/pharmacology , Cross-Sectional Studies , Dose-Response Relationship, Drug , Female , Humans , In Vitro Techniques , Male , Middle Aged , Phytohemagglutinins/pharmacology , Renal Dialysis
20.
Acta Cytol ; 38(6): 939-44, 1994.
Article in English | MEDLINE | ID: mdl-7992583

ABSTRACT

The Cytospin method of fine needle aspiration cytology includes flushing the aspirate into 10 mL of Cytospin fluid; the cytocentrifuge preparations are then safely and conveniently prepared in the laboratory. Slides are stained with Papanicolaou stain and hematoxylin and eosin. From November 1989 through October 1992, 1,868 breast aspirates from palpable lumps were examined by this method at our institution. The method detected 398 of 441 cancers (90.2%); of the 43 that were undetected, 16 had inadequate aspirates, and 27 were falsely reported as negative (for a false-negative rate of 6.0%). There were no false positives; the positive predictive value for malignancy was 100%. The inadequacy rate was 14.8%. Excluding inadequate samples, the complete sensitivity was 95.2%, with 96.5% specificity. The Cytospin method of processing breast aspirates from palpable breast lumps is an acceptable alternative to conventional fine needle aspiration using direct smears. It is also highly convenient as an outpatient procedure, obviating the need for skillful preparation of direct smears.


Subject(s)
Biopsy, Needle/methods , Breast Diseases/diagnosis , Breast Neoplasms/diagnosis , Carcinoma/diagnosis , Breast Diseases/pathology , Breast Neoplasms/pathology , Carcinoma/pathology , Centrifugation , Female , Fixatives , Humans
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