Cyclosporine treatment of glomerular diseases

Metformin ameliorates the severity of experimental Alport syndrome

Metformin is widely used for the treatment of type 2 diabetes, and increasing numbers of studies have shown that metformin also ameliorates tumor progression, inflammatory disease, and fibrosis. However, the ability of metformin to improve non-diabetic glomerular disease and chronic kidney disease (CKD) has not been explored. To investigate the effect of metformin on non-diabetic glomerular disease, we used a mouse model of Alport syndrome (Col4a5 G5X) which were treated with metformin or losartan, used as a control treatment. We also investigated the effect of metformin on adriamycin-induced glomerulosclerosis model. Pathological and biochemical analysis showed that metformin or losartan suppressed proteinuria, renal inflammation, fibrosis, and glomerular injury and extended the lifespan in Alport syndrome mice. Transcriptome analysis showed that metformin and losartan influenced molecular pathways-related to metabolism and inflammation. Metformin altered multiple genes including metabolic genes not affected by losartan. Metformin also suppressed proteinuria and glomerular injury in the adriamycin-induced glomerulosclerosis mouse model. Our results showed that metformin ameliorates the glomerular sclerosis and CKD phenotype in non-diabetic chronic glomerular diseases. Metformin may have therapeutic potential for not only diabetic nephropathy but also non-diabetic glomerular disease including Alport syndrome.

Influence of cyclosporine A on glomerular growth and the effect of mizoribine and losartan on cyclosporine nephrotoxicity in young rats

The aim of this study was to evaluate the influence of cyclosporine A (CsA) on glomerular growth and the effect of mizoribine (MZR) and losartan (LSAR) on CsA-induced nephropathy in young rats. Six-week-old male Sprague-Dawley rats maintained on a low salt diet were given CsA (15 mg/kg), CsA and LSRT (30 mg/kg/day), CsA and MZR (5 mg/kg), or a combination of CsA, LSRT, and MZR for 4 and 7 weeks (two experiments) and compared with control group (olive oil-treated). Histopathology and glomerular size, inflammatory and fibrotic factors were studied. The score of acute CsA toxicity significantly decreased in the CsA + MZR group compared to the CsA group (p < 0.01). MZR and MZR + LSRT reduced tubulointerstitial fibrosis and TGF-β1 mRNA expression at 7 weeks. Osteopontin (OPN) mRNA expression was decreased at 7 weeks in MZR + LSRT (p < 0.01). Glomerular area decreased CsA group and recovered in MZR (p < 0.01) and MZR + LSRT (p < 0.01) at 7weeks. This study demonstrated that MZR and LSRT had suppressive effects on inflammatory process in chronic CsA nephropathy and led to improvement of tubular damage, tubulointerstitial fibrosis and arteriolopathy by down regulation of OPN and TGF-β1 and glomerular size contraction.

Gq signaling causes glomerular injury by activating TRPC6

Familial forms of focal segmental glomerulosclerosis (FSGS) have been linked to gain-of-function mutations in the gene encoding the transient receptor potential channel C6 (TRPC6). GPCRs coupled to Gq signaling activate TRPC6, suggesting that Gq-dependent TRPC6 activation underlies glomerular diseases. Here, we developed a murine model in which a constitutively active Gq α subunit (Gq(Q209L), referred to herein as GqQ>L) is specifically expressed in podocytes and examined the effects of this mutation in response to puromycin aminonucleoside (PAN) nephrosis. We found that compared with control animals, animals expressing GqQ>L exhibited robust albuminuria, structural features of FSGS, and reduced numbers of glomerular podocytes. Gq activation stimulated calcineurin (CN) activity, resulting in CN-dependent upregulation of TRPC6 in murine kidneys. Deletion of TRPC6 in GqQ>L-expressing mice prevented FSGS development and inhibited both tubular damage and podocyte loss induced by PAN nephrosis. Similarly, administration of the CN inhibitor FK506 reduced proteinuria and tubular injury but had more modest effects on glomerular pathology and podocyte numbers in animals with constitutive Gq activation. Moreover, these Gq-dependent effects on podocyte injury were generalizable to diabetic kidney disease, as expression of GqQ>L promoted albuminuria, mesangial expansion, and increased glomerular basement membrane width in diabetic mice. Together, these results suggest that targeting Gq/TRPC6 signaling may have therapeutic benefits for the treatment of glomerular diseases.

Calcineurin inhibitors: 40 years later, can't live without

Calcineurin inhibitors (CNIs) revolutionized the field of organ transplantation and remain the standard of care 40 years after the discovery of cyclosporine. The early impressive results of cyclosporine in kidney transplant recipients led to its subsequent use in other organ transplant recipients and for treatment of a variety of autoimmune diseases as well. In this review, we examine the discovery of CNIs, their mechanism of action, preclinical and clinical studies with CNIs, and the usage of CNIs in nontransplant recipients. We review the mechanisms of renal toxicity associated with CNIs and the recent efforts to avoid or reduce usage of these drugs. Although minimization strategies are possible, safe, and of potential long-term benefit, complete avoidance of CNIs has proven to be more challenging than initially thought.

Predictive factors for ciclosporin-associated nephrotoxicity in children with minimal change nephrotic syndrome

Aims

To identify the predictive factors for ciclosporin A (CyA)-associated nephrotoxicity (CAN) in children with minimal change nephrotic syndrome (MCNS).

Methods

The clinical and laboratory findings of 58 children (median age 3.2 years, range 1.1–13.1 years, male:female 48:10) with MCNS who were treated with CyA from 1992 to 2002 were analysed retrospectively. Forty-eight (83%) of them were steroid dependent and 10 (17%) were steroid resistant. The starting dose of CyA was 5 mg/kg per day, and the desired drug level was kept at 100–200 ng/ml. Serial renal biopsies were performed before and after CyA therapy.

Results

Twenty-two patients (38%) had CAN (group I) and 36 (62%) did not (group II). There were no differences in the age at onset, sex, initial response to steroids, duration of CyA therapy and relapse rates. However, the median CyA trough levels were significantly higher in group I than in group II (218.0±15.2 vs 171.8±6.7 ng/ml, p=0.01). Changes in creatinine clearance were more decreased in group I than in group II (−39.4±8.2 vs 2.7±4.3 ml/min per 1.73 m2, p<0.0001). Multiple logistic regression analysis also revealed the median CyA trough level was an independent risk factor for the development of CAN (OR 1.025, 95% CI 1.007 to 1.044, p=0.007).

Conclusions

The median CyA trough level was an independent and significant risk factor for the development of CAN in children with MCNS receiving moderate-dose CyA.

Effects of cyclosporin A therapy combined with steroids and angiotensin converting enzyme inhibitors on childhood IgA nephropathy

To evaluate the effects of cyclosporin A (CyA) on clinical outcome and pathologic changes in children with IgA nephropathy (IgAN), we retrospectively evaluated 14 children (mean age 8.9+/-2.9 yr; eight males, six females) who were treated with CyA and steroids. The starting dose of CyA was 5 mg/kg per day, and the drug level was maintained at 100-200 ng/mL. The mean CyA level was 183.8+/-48.3 ng/mL (range 120.7-276.0 ng/mL) and the mean duration of CyA therapy was 10.9+/-1.9 months (range 8-12 months). After CyA therapy the mean 24 hr urinary protein excretion declined from 107.1+/-35.1 mg/m(2)/hr to 7.4+/-2.4 mg/m(2)/hr (P<0.001) and serum albumin increased from 3.3+/-0.6 g/dL to 4.3+/-0.3 g/dL (P<0.001). At a follow-up biopsy the histological grade of IgAN was improved in seven (50%) of the 14 patients, remained the same in three (21%), and was aggravated in four (29%). Serum creatinine, creatinine clearance, and blood pressure did not differ before and after CyA therapy. Two patients (14%) showed CyA-induced nephrotoxicity at the second biopsy. Our findings indicate that CyA therapy may be effective in reducing proteinuria and regressing renal pathology in a subset of children with IgAN.

[Focal segmental glomerulosclerosis]

Focal segmental glomerulosclerosis is a glomerular injury with typical morphology detectable by light microscopy. It has different histological subtypes and clinical symptoms. These different subtypes were recently systematized (Columbia classification). Focal segmental glomerulosclerosis is considered as the major type of podocytopathies, because podocytes are affected at each type of glomerular injury. Besides the primary forms of focal segmental glomerulosclerosis, an increased number of the secondary types are recognized. The wide use of drugs for renal protection in general and the long term administration of steroid therapy in some primary (idiopathic) cases are new elements among the therapeutic possibilities.

A Potential Side Effect of Cyclosporin A: Inhibition of CD4+CD25+ Regulatory T Cells in Mice

BACKGROUND

CD4CD25 regulatory T (Treg) cells are essential for the induction and maintenance of immunologic self-tolerance as well as transplant tolerance. The effects of cyclosporin A (CsA), a widely used immunosuppressive agent, on CD4CD25Treg cells in mice were investigated.

METHODS

Balb/c mice were injected with CsA or control solution for one month. The levels, phenotype, and function of CD4CD25Treg cells in these mice were then assayed.

RESULTS

The percentages and total cell numbers of CD4CD25Treg cells in the peripheral blood and spleen were significantly reduced after the treatment with CsA. The total numbers of CD4CD25Treg cells in the thymus of CsA-treated mice were markedly reduced as compared to the control mice. However, the percentage of CD4CD25Treg cells in the thymus of CsA-treated mice was markedly enhanced. More CD4CD25Treg cells expressing high levels of CD44 and CD45RB, and less CD4CD25Treg cells expressing CD62L were observed in CsA-treated mice, compared with the control mice. CD4CD25Treg cells expressed slightly lower levels of Foxp3 in CsA-treated mice. Furthermore, CsA markedly impaired the immunosuppressive function of CD4CD25Treg cells.

CONCLUSIONS

CsA significantly impaired the development and function of CD4CD25Treg cells. The present studies suggest that CsA may block the potential induction of immune tolerance and increase the susceptibility to develop autoimmune diseases while preventing graft rejection.

Henoch-Schönlein purpura nephritis with nephrotic-range proteinuria: histological regression possibly associated with cyclosporin A and steroid treatment

OBJECTIVE

To clarify the therapeutic role of cyclosporin A (CyA) for patients with Henoch-Schönlein purpura nephritis (HSPN) showing nephrotic-range proteinuria.

METHODS

The clinical and histological findings of eight children (7.7+/-3.8 years), who were treated with CyA and prednisolone, were evaluated retrospectively. All underwent a renal biopsy before therapy, and six of the eight patients received a follow-up biopsy after therapy.

RESULTS

The histological grade of the International Study of Kidney Disease in Children (ISKDC) was improved in all six patients who received a follow-up biopsy (pre-therapy, four grade IIIa and two grade IIIb; post-therapy, one grade I and five grade II) and it was statistically significant (p = 0.031). The activity index was significantly decreased after therapy (8.3+/-1.6 vs. 3.5+/-1.5, p = 0.031), and the chronicity index (0.5+/-0.5 vs. 0.7+/-1.0) and tubulointerstitial (TI) scores (1.5+/-1.3 vs. 0.8+/-1.6) did not change. There was a reduction in proteinuria from 3.2+/-2.3 to 0.1+/-0.1 g/m2/day (p = 0.008) and renal function remained normal in all patients after therapy. However, one patient showed CyA-induced nephrotoxicity at a second biopsy. After an average follow-up period of 3.8 years, six patients showed normal urine and renal function, and two showed minor urinary abnormalities.

CONCLUSION

This study suggests that CyA therapy is effective in reducing proteinuria, which is a known risk factor for the development of renal insufficiency in HSPN and may regress the renal pathology in patients with nephrotic-range proteinuria.

Long-term effects of cyclosporine in children with idiopathic nephrotic syndrome: a single-centre experience

BACKGROUND

Because of its potential nephrotoxicity, the long-term use of cyclosporine (CsA) as treatment for nephrotic syndrome (NS) is controversial. The clinical outcome of the patients with NS treated with CsA is unclear.

METHODS

This study reports the results of long-term CsA treatment in 117 children with idiopathic NS, who received CsA therapy for more than 2 years (median, 34 months). The mean age of children at initiation of CsA therapy was 11+/-4 years. The starting dose of CsA was 5 mg/kg/day, adjusted to maintain a trough level of 100-150 ng/ml in the first 2 months, 50-100 ng/ml thereafter. Later, a level as low as 30 ng/ml was accepted so long as it maintained remission. All patients received CsA between 1993 and 2003. Indications for treatment included steroid-dependent nephrotic syndrome (SDNS) in 74 patients and steroid-resistant nephrotic syndrome (SRNS) in 43 patients. Initial renal histology showed minimal change disease (MCD) in 38 patients and focal segmental glomerulosclerosis (FSGS) in 79 patients. Most patients were receiving moderate doses of prednisone. Sixty patients received cyclophosphamide prior to CsA. The observation periods were 5.8+/-3 years and 6.1+/-1.9 years before and after CsA treatment, respectively.

RESULTS

Complete remission [proteinuria <4 mg/h/m2/body surface area (BSA)], partial remission (proteinuria between 4.1 and 40 mg/h/m2/BSA) and resistance to CsA (proteinuria > or = 45 mg/h/m2/BSA) were observed in 82.1, 5.1 and 12.8%, respectively. Hypertension, renal impairment (>30% rise of serum creatinine), gingival hyperplasia and hypertrichosis occurred in 10.3, 6.0, 32.5 and 70.1%, respectively. Steroids were stopped in 102 patients, of which 31 relapsed. Out of 29 patients for whom CsA was intentionally discontinued while in remission, 22 relapsed. Of these, six patients were resistant to a second course of CsA. Post-therapy biopsies, performed in 45 patients (33 with SDNS and 12 with SRNS), showed mild stripped interstitial fibrosis and tubular atrophy in two SDNS patients (4.4%). At the last follow-up, one child had developed end-stage renal failure and two had chronic renal insufficiency.

CONCLUSIONS

Long-term CsA therapy in low doses is effective in the treatment of children with idiopathic NS, but the rate of relapse is high after drug withdrawal. Hypertension developed in 10% of patients and renal insufficiency in 6% (most patients with FSGS).

Cyclosporin A therapy for severe Henoch-Schönlein nephritis with nephrotic syndrome

To evaluate the efficacy of cyclosporin A (CyA) for treating severe Henoch-Schönlein nephritis (HSN), seven patients with nephrotic syndrome, aged 3.9-13.8 years (mean 6.5 years), were analyzed retrospectively. Mean follow-up times were 5.5 years (range 2-9 years). All underwent renal biopsy before treatment, and follow-up renal biopsy was performed in six of the seven patients. All patients improved, with 24-h protein declining from a mean of 9.2 g/m(2)/day (range 1.5-16 g/m(2)/day) to 0.3 g/m(2)/day (range 0.03-1.2 g/m(2)/day) (p=0.016) and serum albumin increasing from a mean of 2.1 g/dl (range 1.5-2.4 g/dl) to 4.6 g/dl (range 3.5-5.3 g/dl) (p=0.016) after CyA therapy. The activity index decreased significantly at the second renal biopsies obtained at a mean interval of 11.7 months after the first (6.4+/-3.3 vs 3.5+/-1.2, p=0.042, respectively), while the chronicity index and the tubulointerstitial scores did not change. On the immunofluorescent findings at the second biopsies, the degree of deposits of immunoglobulins such as IgA, IgM, C3, and fibrinogen decreased in five of the six patients. Although this case series is without controls, our study suggests that CyA may be beneficial to a subset of HSN patients with nephrotic syndrome.

Anti-fungal Activity of Sulfamethoxazole toward Aspergillus Species

Invasive mycosis has significantly increased in frequency among immunocompromised hosts leading to excessive morbidity and mortality. The combination of sulfamethoxazole (SMX) and trimethoprim (TMP) has been used extensively for the treatment and prophylaxis of infections by various microbes. The purpose of this study is to estimate the anti-fungal activity of SMX-TMP and examine the mechanism of activity. To investigate the antimicrobial activity of SMX-TMP in vitro, a mixture of SMX and TMP at 5:1 was serially diluted and added to potato dextrose agar medium or C-limiting agar medium. Aspergillus species were inoculated on the medium plate with SMX-TMP. The growth of A. fumigatus and A. oryzae was inhibited by addition of SMX-TMP. The anti-Aspergillus effect depended on not TMP but SMX and that was inhibited by p-aminobenzoic acid (PABA). A. niger was not sensitive against SMX-TMP in PDA medium, but sensitive in C-limiting medium. Those results showed that the activity depends on culture medium. Furthermore, addition of human serum did not influence the activity of SMX. The finding in this study suggested that SMX might be effective against Aspergillus species in clinical practice and prophylaxis treatment.

Egress: a receptor-regulated step in lymphocyte trafficking

Blood lymphocyte numbers, which are maintained by recirculation through secondary lymphoid organs, are essential for the efficient development of immune responses. Recirculating populations of B and T lymphocytes are regulated by the sphingosine-1-phosphate (S1P) receptor-dependent control of lymphocyte egress. T-cell egress from thymus into blood, egress from lymph node and Peyer's patch into lymph, and B-cell egress into lymph are rapidly and completely inhibited by agonism of S1P receptors. Mesenteric lymph nodes show log-jamming of lymphocytes subjacent to sinus-lining endothelium. Agonism of S1P receptors produces rapid peripheral blood lymphopenia, which is maintained in the presence of receptor agonist. Effector CD4+ and CD8+ T cells, produced by clonal expansion in draining lymph node in response to antigen, are sequestered in lymph node and fail to reach the peripheral blood. The S1P receptor system may represent an early physiological link between the non-specific inflammatory response and the alteration of lymphocyte traffic through draining lymph nodes. Pharmacological subversion of the S1P receptor system, through systemic S1P agonist-induced inhibition of lymphocyte egress, suppresses antigenic responses to peripheral, but not to systemically, delivered antigen. This inhibition induces significant immunosuppression in models of transplantation and autoimmune tissue damage that may prove to be of clinical benefit.

Cerebral lupus in patients whilst on treatment for lupus nephritis with cyclosporine

Two young female patients who were treated for severe lupus nephritis with cyclosporine, developed, while the renal parameters remained stable, signs of cerebral lupus (bilateral papiloedema and cranial nerve palsy in one patient and grand mal seizures in the second). The first patient responded to plasmapheresis and i.v. cyclophosphamide, and the second to temporary increase in prednisone with anti-convulsant medication. Both case histories suggest that cyclosporine, whilst controlling lupus nephritis, was not able to prevent serious attacks of cerebral lupus. This discrepancy might be related to relative inability of the drug to reduce antibody production or to the existence of heterogeneous pathogenetic mechanisms of lupus in different organ systems.

Expression of matrix metalloproteinases in cyclosporin-treated gingival fibroblasts is regulated by transforming growth factor (TGF)-beta1 autocrine stimulation

BACKGROUND

Gingival overgrowth is a common side effect following the administration of cyclosporin A (CsA). The pathogenesis of this condition is not fully understood; however, recent studies show that CsA regulates the transcription of several cytokines including transforming growth factor-beta1 (TGF-beta1). The aim of this study was to investigate the potential role of TGF-beta1 in the pathogenesis of CsA-induced gingival overgrowth, exploring a possible autocrine stimulation of TGF-beta1 as a cellular regulator of synthesis of matrix metalloproteinases (MMPs) and its tissue inhibitors (TIMPs).

METHODS

Gingival fibroblasts from human normal gingiva were incubated with increasing concentrations of CsA, cultured for 24 hours, and the expression and production of TGF-beta1 determined by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. MMP and TIMP mRNA expression levels were also analyzed by RT-PCR. To determine the effect of TGF-beta1 on the expression of MMP and TIMP by human gingival fibroblasts under CsA treatment, human gingival fibroblast cultures were treated with sense oligonucleotides (SON) or antisense oligonucleotides (AON).

RESULTS

CsA simultaneously stimulated TGF-beta1 expression and production and inhibited expression of MMP-1 and MMP-2 by human gingival fibroblasts, whereas CsA has a slight effect on TIMP-1 and TIMP-2 expression. AON reduced TGF-beta1 production as demonstrated by ELISA, whereas TGF-beta1 mRNA expression levels were not significantly modified. The inhibition of TGF-beta1 production by AON modulated MMP expression, demonstrating the autocrine inhibitory effect of TGF-beta1 in CsA-treated human gingival fibroblasts.

CONCLUSIONS

The data presented here suggest that TGF-beta1 in an autocrine fashion may contribute to a reduction of proteolytic activity of human gingival fibroblasts in CsA-induced gingival overgrowth, which favors the accumulation of extracellular matrix.

Ovariectomy aggravates convulsions and hippocampal gamma-aminobutyric acid inhibition induced by cyclosporin A in rats

The possible cyclosporin A application for rheumatoid arthritis that develops preferentially in middle-aged women raises concerns about adverse effects of cyclosporin A, including neurotoxicity in patients with climacterium. The present study was aimed at elucidating the effect of cyclosporin A on the convulsive activity and gamma-aminobutyric acid (GABA) neural activity of the hippocampus in ovariectomized rats, as a menopause/climacterium model. Ovariectomy markedly aggravated the effect of repeated administration of cyclosporin A (40 mg/kg, once a day for 5 or 6 days), convulsions and reduction of the basal GABA levels and aminooxyacetic acid-evoked GABA accumulation. These aggravations were blocked by estradiol replacement. The present findings demonstrated that ovariectomy increased the susceptibility to cyclosporin A-induced convulsions by accelerating an inhibitory action of cyclosporin A on GABA neural activity in the hippocampus, this being blocked by estrogen replacement. Menopause/climacterium is, therefore, included in the risk factors for cyclosporin A-induced neurotoxicity and this risk is lowered by estrogen replacement therapy.

Advances in the treatment of lupus nephritis

Systemic lupus erythematosus (SLE) is an autoimmune disease that leads to the formation and deposition of immune complexes throughout the body, which are pathogenic for the disease. Different forms of glomerulonephritis can occur in patients with SLE and can contribute significantly to the associated morbidity and, ultimately, mortality from the disease. Over the past two decades, there have been significant strides in our understanding of the disease and in treatments that attempt to control the formation and deposition of anti-DNA auto-antibodies and immune complexes, as well as the subsequent inflammatory cascade mediated through various cellular and humoral pathways leading to progressive renal damage and end-stage renal disease. In this chapter, we review the current understanding of the pathogenesis and treatment of lupus nephritis in its various stages and discuss the experimental and human data regarding some of the potential newer forms of therapy. We discuss data regarding the use of steroids, azathioprine, cyclophosphamide, cyclosporine A, mycophenolate mofetil, gammaglobulin, plasmapheresis, LJP 394, flaxseed oil, bindarit, anti-CD40 ligand, and CTLA4Ig.

Hepatocyte growth factor, but not insulin-like growth factor I, protects podocytes against cyclosporin A-induced apoptosis

Cyclosporin A (CsA) nephropathy is associated with altered expression of apoptosis regulatory genes such as Fas-ligand and Bcl-2 family members in the glomerular, tubulointerstitial, and vascular compartments. Both hepatocyte growth factor (HGF) and insulin-like growth factor (IGF-I) protect against apoptosis, and HGF specifically up-regulates Bcl-xL, a protein that regulates apoptosis. We investigated whether Bcl-xL and Fas/Fas-ligand were regulated by CsA in cultured podocytes and whether CsA-induced apoptosis was prevented by HGF or IGF-I. A murine podocyte cell line was treated with CsA in the presence or absence of HGF or IGF-I. Apoptosis was quantitated by ELISA and by flow cytometry; Bcl-xL, Fas, and Fas-ligand were measured by Western blotting. Inhibitors of MAP kinase/ERK kinase (MEK)-1 and of phosphatidylinositol 3'-kinase (PI3'-K) were used to determine the signaling pathways involved in Bcl-xL regulation. Apoptosis was induced by CsA in a dose- and time-dependent fashion. CsA also decreased Bcl-xL levels. HGF, but not IGF-I, prevented apoptosis and restored Bcl-xL levels. The regulation of Bcl-xL by HGF was mediated by the PI3'-K but not by the MEK-1 pathway. In summary, we showed that CsA induces apoptosis in podocytes. Apoptosis was prevented by pretreatment with HGF but not IGF-I. Decreased apoptosis appeared to be mediated by regulation of Bcl-xL via the PI3'-K pathway. Our data suggest that the effect of CsA on podocytes may contribute to the glomerular damage and that HGF could provide protection.

Progress in the treatment of proliferative lupus nephritis

Lupus nephritis is often well developed at the time of diagnosis. High-dose corticosteroids are universally accepted as the initial approach to the control of severe inflammation in the kidney. Long-term disease control and the minimization of iatrogenic risk usually require adjunctive therapies that target the more fundamental immunoregulatory disturbances of lymphoid cells. Of the available cytotoxic drugs, cyclophosphamide is currently among the most effective, although it cannot be considered ideal in terms of efficacy or toxicity. New prospects for the treatment of proliferative lupus nephritis include novel immunosuppressive agents (e.g. mycophenolate, cyclosporine, fludarabine), combination chemotherapy (e.g. cyclophosphamide plus fludarabine), and sequential chemotherapy (e.g. cyclophosphamide-azathioprine), immunological reconstitution using intensive cytoreductive chemotherapy (with or without stem cell rescue), co-stimulatory molecule inhibition (e.g. humanized anti-CD154 monoclonal antibody, CTLA4-Ig). Gene therapy remains an attractive prospect, but its feasibility clearly depends on the further definition of lupus-promoting genes and the availability of methods to establish stable expression of disease-corrective genes in the appropriate lymphoid cells.