The Official Patient's Sourcebook on Lupus (11 page)

Principal Investigator & Institution: Holers, Michael; University of

Colorado Hlth Sciences Ctr 4200 E 9Th Ave Denver, Co 80262

Timing: Fiscal Year 2000

Summary: This is an investigator-initiated collaborative Phase II

treatment study in which we will examine the hypothesis that treatment

of patients with systemic lupus erythematosus (SLE) and active lupus

nephritis with a blocking anti-human complement C5 monoclonal

antibody will lead to objective improvement in renal disease parameters.

The anti-C5 monoclonal antibody will lead to objective improvement in

renal disease parameters. The anti-G5 monoclonal antibody will be

provided by Alexion Pharmaceuticals. Several lines of investigation have

supported the concept that C5 plays a central role in renal injury in

antibody- mediated diseases such as SLE. While short term studies using

a similar inhibitor have shown efficacy in patients with inflammatory

complications of coronary artery bypass surgery, the proposed study

54 Lupus Nephritis

represents the first application of this therapeutic strategy, chronic

inhibition of complement C5 activation, to patients with autoimmune

diseases. Patients enrolled in this double blinded, placebo controlled

Phase II study will be those who have active but clinically stable nephritis

and, thus, do not require immediate introduction of high dose

cyclophosphamide or other cytotoxic drug therapy. Two patient groups,

treated and untreated (vehicle control only as a placebo), will be studied.

The primary outcome variable will be proteinuria. Secondary outcomes

will include other measures of renal disease activity, other measures of

lupus activity and measure of complement activation. Three Specific

Aims will be pursued. Specific Aim #1. Determine the changes in renal

disease activity that accompany short term treatment with an anti-C5

monoclonal antibody in patients with active lupus nephritis. Specific Aim

#2. Identify changes in levels of complement activation fragments that

accompany treatment with anti-c5 monoclonal antibody in patients with

active lupus nephritis. Specific Aim #3. Assess these patients treated with

an inhibitory anti-C5 monoclonal antibody for evidence of toxicity. This

study is integrated into other components and goals of the Denver

Autoimmunity Center itself in several ways. First, it utilizes a population

of patients drawn from several sources in the Denver Autoimmunity

Center. Second, it meets the goal of extending the use of complement

inhibitors from animal models, which are being extensively studied here

in the laboratory of the P.I. and others, into clinical trials in patients.

Third, the analysis of the role of complement inhibitors as compared to

cytokine inhibitors is a major component of the Basic Science Project #2

headed by Dr. William P. Arend.

Website: http://commons.cit.nih.gov/crisp3/CRISP.Generate_Ticket

·
Project Title: Immune Mechanisms in Pristane Induced Lupus

Nephritis

Principal Investigator & Institution: Reeves, Westley H.; Professor;

Medicine; University of Florida Gainesville, Fl 32611

Timing: Fiscal Year 2000; Project Start 1-JAN-1999; Project End 1-DEC-

2003

Summary: Intraperitoneal injection of pristane (2,6, 10, 14-

tetramethylpentadecane) induces a lupus-like syndrome in nearly all

"normal" strains of inbred mice. This syndrome is characterized by

disease-specific autoantibody production (anti-Sm, RNP, Su, ribosomal P,

double stranded DNA), hypergammaglobulinemia, and severe immune

complex-mediated glomerulonephritis closely resembling lupus

nephritis. In preliminary studies, it was shown that the disease develops

in two phases, each with characteristic types of autoantibodies. cytokines,

Studies 55

and renal involvement. Microbial stimulation was found to be an

important co-factor in progression to the second. more severe, phase.

This project will examine the hypothesis that immune complex

deposition is necessary, but not sufficient, for the development of

nephritis in pristane-induced lupus. Further, it is hypothesized that a

systemic abnormality in macrophage or monocyte phenotype resulting

from pristane and/or microbial stimulation leads to the production of

proinflammatory cytokines and disease progression. The goal of this

project is to define pathways leading to glomerulonephritis in pristane-

treated mice and ultimately to relate them to human lupus nephritis.

Three specific aims are proposed. The pathology of the renal lesions will

be defined in Aim 1. Mesangial and mesangiocapillary lesions will be

studied by immunohistochemical techniques to determine whether

hypercellularity reflects proliferation of endogenous (mesangial or

endothelial) cells vs. influx of exogenous macrophages, lymphocytes or

neutrophils. In addition, mesangial matrix deposition will be evaluated,

and the time course of the renal changes will be studied. The roles of pro-

vs. anti- inflammatory cytokines will be evaluated in Aim 2. Cytokine

production in the glomerulus will be compared with that by phagocytes

in the peritoneal exudate, spleen and liver to see if systemic abnormalities

are present. Expression of cytokine-inducible markers will be studied as a

means to evaluate whether the effects of pro-or anti-inflammatory

cytokines predominate. The contribution of microbial stimulation to the

development of nephritis in pristane-induced lupus will be examined in

Aim 3. It is hypothesized that enhanced intestinal permeability resulting

from pristane injection increases the translocation of microbial products,

such as lipopolysaccharide, into the bloodstream. This may cause

systemic activation of monocytes and macrophages, which then are

recruited to the glomerulus in response to immune complex deposition,

causing progression instead of resolution of the renal lesion. In view of

the widespread susceptibility among "normal" mice to pristane-induced lupus, it seems likely that pristane causes lupus- like disease by its effects on a common, distal, part of a lupus pathway, largely bypassing the

genetic abnormalities that predispose to spontaneous forms of the

disease. The mechanisms involved in this new inducible model of SLE

may, therefore, be common to other forms of lupus, including human

SLE. Future studies will address the question of whether renal

abnormalities similar to those induced by pristane are involved in the

pathogenesis of human lupus nephritis.

Website: http://commons.cit.nih.gov/crisp3/CRISP.Generate_Ticket

56 Lupus Nephritis

·
Project Title: Immunologic Mechanism in Lupus Nephritis

Principal Investigator & Institution: Madaio, Michael P.; Associate

Professor; Medicine; University of Pennsylvania 1 College Hall

Philadelphia, Pa 19104

Timing: Fiscal Year 2000; Project Start 1-JAN-1985; Project End 0-JUN-

2002

Summary: (Adapted from Investigator's Abstract): The overall aim of this

project is to develop a better understanding of the immunologic events

leading to glomerular immune deposit formation in individuals with

Systemic Lupus Erythematosus. In previous studies, murine and human

monoclonal anti-DNA antibodies (Ab) were identified that produced

glomerulonephritis following transfer to normal mice. Of particular

relevance, the location of immune deposit formation and disease

phenotype varied with the mAb. Furthermore, these individual

pathogenic Ab bound directly to glomerular cell surface antigens,

however each monoclonal anti-DNA Ab recognized a different cell

surface proteins. Based on these observations, it was postulated that

different autoantibody-glomerular antigen interactions, in vivo,

contributes to the phenotypic diversity observed both among the

monoclonal Ab and among individuals with lupus. A primary goal of

this project is to fully identify the glomerular cell surface antigens for

three nephritogenic lupus autoantibodies: anti-DNA MES and anti-DNA

SE, derived from MRL-lpr/lpr mice; and RH-14, a human anti-DNA Ab.

Anti-DNA MES produces mesangial deposits and binds to mesangial

cells, whereas anti-DNA SE produces subendothelial deposits and binds

to glomerular endothelial cells. RH14 produces massive subendothelial

deposits on transfer to SCID mice, and it binds to glomerular endothelial

cells. Candidate cell surface protein antigens were isolated for the

autoantibodies. Peptides derived from the isolated proteins will be

sequenced and then used to generate both degenerate oligonucleotides

and anti-peptide antibodies to screen cDNA libraries, in order to define

the full sequence and identity of the immunoreactive proteins. Another

primary goal of the project is to further determine the pathogenic

relevance of these autoantibody-glomerular cell interactions by

examining: i) the immune response to the purified cell surface proteins,

ii) other spontaneously produced autoantibodies with anti-cell surface

protein activity; and iii) the cellular and functional consequences of Ab

ligation of the cell surface proteins. Studies will be performed to begin to

determine the overall relevance of direct binding of human lupus

autoantibodies to glomerular antigens, in general, using: human lupus

sera from the Lupus Collaborative Study and controls, the purified cell

surface antigens, and individual glomerular cells. Collectively, the results

Studies 57

should identify disease-relevant glomerular antigens for pathogenic

lupus autoantibodies and provide insights into the overall pathogenic

relevance of autoantibody-glomerular cell surface antigen interactions in

lupus nephritis.

Website: http://commons.cit.nih.gov/crisp3/CRISP.Generate_Ticket

·
Project Title: Cell Mediated Renal Injury in Lupus

Principal Investigator & Institution: Kelley, Vicki R.; Associate Professor; Brigham and Women's Hospital 75 Francis St Boston, Ma 02115

Timing: Fiscal Year 2000; Project Start 1-FEB-1985; Project End 0-NOV-

2002

Summary: The broad objective of this proposal is to test the hypothesis

that increased intrarenal macrophage colony stimulating factor (CSF-1)

expression is central to the pathogenesis of autoimmune renal disease in

MRL-lpr/lpr mice. Using the MRL-lpr/lpr mouse with rapid, uniform,

severe and predictable renal disease regulated by the lpr gene we will

investigate the importance of CSF-1 in the pathogenesis of lupus

nephritis. We propose to test whether the increase in circulating CSF-1

detected in neonatal MRL-lpr/lpr mice is contributed by the kidney alone

or if other tissues are responsible for elevating serum levels. We will

establish whether a molecule(s) in the circulation of MRL-lpr/lpr mice

induces intrarenal CSF-1. We will determine whether increased renal

expression of CSF-1 recruits macrophages. We will then investigate

whether an increased expression of CSF-1 can induce renal disease in

mice with normal kidneys including another strain with the lpr gene

(C3H- lpr/lpr) and C3H-++ mice or accelerate an indolent, mild nephritis

in congenic MRL-++, lacking the lpr gene. We will eliminate CSF-1 by

creating a cytokine deficient MRL-lpr/lpr mouse and evaluate the impact

on the development of lupus nephritis. In the event that the CSF-1

deficient MRL-lpr/lpr strain does not develop lupus nephritis we will

determine if the inability of renal cells to express CSF-1 is responsible for

preventing kidney disease. Through the advent of cellular and molecular

techniques we now have the capacity to transfer a cytokine gene using a

retroviral vector and establish tubular epithelial (TEC) and mesangial cell

lines which can constitutively secrete high levels of a stable cytokine. By

implanting these cells under the renal capsule we have created a system

to introduce the continuing presence of CSF-1 (or other cytokines) into

the kidney. We can then establish if CSF-1 recruits macrophages and

determine whether CSF-1 will induce or accelerate renal injury in the

MRL-++, C3H-lpr/lpr strains. To definitely establish whether CSF-1 or

other cytokines have an enhanced glomerular expression prior to the

influx of macrophages, we will isolate and pool individual glomeruli

58 Lupus Nephritis

(glom) from MRL-lpr/lpr, congenic, and normal mice at varying ages

and quantitate the level of cytokine and macrophages specific marker

mRNA using the competitive template polymerase chain reaction.

Finally, we will cross the MRL-++ or the C3H- lpr/lpr mice with CSF-1

transgenic mice and select for hybrids with these backgrounds

overexpressing macrophage growth factors. In addition, we will

eliminate CSF-1 from MRL-lpr/lpr mice by crossing them with the op/+

strain and select for a strain with op/op (producing a non-functional

CSF-1) and lpr genes. By increasing or eliminating CSF-1, we will test the

impact of this cytokine in promoting renal disease. In addition, we will

use the approach of transplanting a kidney into a bilaterally

nephrectomized recipient to determine when the MRL-lpr/lpr kidney is