Utilization of intravenous immunoglobulin therapy to treat recurrent pregnancy loss in the antiphospholipid syndrome: a review

Immune modulation of i.v. immunoglobulin in women with reproductive failure

Background

The mechanism of maternal immune tolerance of the semi‐allogenic fetus has been explored extensively. The immune reaction to defend from invasion by pathogenic microorganisms should be maintained during pregnancy. An imbalance between the immune tolerance to the fetus and immune activation to the pathogenic organisms is associated with poor pregnancy outcomes. This emphasizes that the immune mechanism of successful reproduction is not just immune suppression, but adequate immune modulation.

Methods

In this review, the action of i.v. immunoglobulin G (IVIg) on the immune system and its efficacy in reproductive failure (RF) was summarized. Also suggested is the indication of IVIg therapy for women with RF.

Main findings (Results)

Based on the mechanism of the immune regulation of IVIg and following confirmation of the immune modulation effects of it in various aberrant immune parameters in patients with RF, it is obvious that IVIg is effective in recurrent pregnancy losses and repeated implantation failures with immunologic disturbances.

Conclusion

The authors recommend IVIg therapy in patients with RF with aberrant cellular immunologic parameters, including a high natural killer cell proportion and its cytotoxicity or elevated T helper 1 to T helper 2 ratio, based on each clinic's cut‐off values. Further clinical studies about the safety of IVIg in the fetus and its efficacy in other immunologic abnormalities of RF are needed.

Antiphospholipid antibody profile based obstetric outcomes of primary antiphospholipid syndrome: the PREGNANTS study

BACKGROUND

Antiphospholipid syndrome is an autoimmune, hypercoagulable state that is caused by antiphospholipid antibodies. Anticardiolipin antibodies, anti-β2 glycoprotein-I, and lupus anticoagulant are the main autoantibodies found in antiphospholipid syndrome. Despite the amassed body of clinical knowledge, the risk of obstetric complications that are associated with specific antibody profile has not been well-established.

OBJECTIVE

The purpose of this study was to assess the risk of obstetric complications in women with primary antiphospholipid syndrome that is associated with specific antibody profile.

STUDY DESIGN

The Pregnancy In Women With Antiphospholipid Syndrome study is a multicenter, retrospective, cohort study. Diagnosis and classification of antiphospholipid syndrome were based on the 2006 International revised criteria. All women included in the study had at least 1 clinical criteria for antiphospholipid syndrome, were positive for at least 1 antiphospholipid antibody (anticardiolipin antibodies, anti-β2 glycoprotein-I, and/or lupus anticoagulant), and were treated with low-dose aspirin and prophylactic low molecular weight heparin from the first trimester. Only singleton pregnancies with primary antiphospholipid syndrome were included. The primary outcome was live birth, defined as any delivery of a live infant after 22 weeks gestation. The secondary outcomes were preeclampsia with and without severe features, intrauterine growth restriction, and stillbirth. We planned to assess the outcomes that are associated with the various antibody profile (test result for lupus anticoagulant, anticardiolipin antibodies, and anti-β2 glycoprotein-I).

RESULTS

There were 750 singleton pregnancies with primary antiphospholipid syndrome in the study cohort: 54 (7.2%) were positive for lupus anticoagulant only; 458 (61.0%) were positive for anticardiolipin antibodies only; 128 (17.1%) were positive for anti-β2 glycoprotein-I only; 90 (12.0%) were double positive and lupus anticoagulant negative, and 20 (2.7%) were triple positive. The incidence of live birth in each of these categories was 79.6%, 56.3%, 47.7%, 43.3%, and 30.0%, respectively. Compared with women with only 1 antibody positive test results, women with multiple antibody positive results had a significantly lower live birth rate (40.9% vs 56.6%; adjusted odds ratio, 0.71; 95% confidence interval, 0.51-0.90). Also, they were at increased risk of preeclampsia without (54.5% vs 34.8%; adjusted odds ratio, 1.56; 95% confidence interval, 1.22-1.95) and with severe features (22.7% vs 13.8%, adjusted odds ratio, 1.66; 95% confidence interval, 1.19-2.49), of intrauterine growth restriction (53.6% vs 40.8%; adjusted odds ratio, 2.31; 95% confidence interval, 1.17-2.61) and of stillbirth (36.4% vs 21.7%; adjusted odds ratio, 2.67; 95% confidence interval, 1.22-2.94). In women with only 1 positive test result, women with anti-β2 glycoprotein-I positivity present alone had a significantly lower live birth rate (47.7% vs 56.3% vs 79.6%; P<.01) and a significantly higher incidence of preeclampsia without (47.7% vs 34.1% vs 11.1%; P<.01) and with severe features (17.2% vs 14.4% vs 0%; P=.02), intrauterine growth restriction (48.4% vs 40.1% vs 25.9%; P<.01), and stillbirth (29.7% vs 21.2% vs 7.4%; P<.01) compared with women with anticardiolipin antibodies and with women with lupus anticoagulant present alone, respectively. In the group of women with >1 antibody positivity, triple-positive women had a lower live birth rate (30% vs 43.3%; adjusted odds ratio,0.69; 95% confidence interval, 0.22-0.91) and a higher incidence of intrauterine growth restriction (70.0% vs 50.0%; adjusted odds ratio,2.40; 95% confidence interval, 1.15-2.99) compared with double positive and lupus anticoagulant negative women.

CONCLUSION

In singleton pregnancies with primary antiphospholipid syndrome, anticardiolipin antibody is the most common sole antiphospholipid antibody present, but anti-β2 glycoprotein-I is the one associated with the lowest live birth rate and highest incidence of preeclampsia, intrauterine growth restriction, and stillbirth, compared with the presence of anticardiolipin antibodies or lupus anticoagulant alone. Women with primary antiphospholipid syndrome have an increased risk of obstetric complications and lower live birth rate when <1 antiphospholipid antibody is present. Despite therapy with low-dose aspirin and prophylactic low molecular weight heparin, the chance of a liveborn neonate is only 30% for triple-positive women.

Antiphospholipid syndrome in pregnancy

PURPOSE OF REVIEW

Antiphospholipid syndrome is widely recognized as a risk factor for numerous obstetric complications including miscarriage, intrauterine growth restriction, preeclampsia, fetal death and preterm labour. The many recent changes in concept regarding this syndrome, the role of the relevant antibodies, mechanism of action, diagnosis and treatment are assessed in this review.

RECENT FINDINGS

In recent years, our understanding of antiphospholipid syndrome has grown. The antigen has become better defined and is now thought to be beta2 glycoprotein 1. The 'classical' antibodies, lupus anticoagulant and anticardiolipin antibody are known to be pathogenic even when passively transferred to animal hosts. It seems, however, that the pathogenic antibodies are those directed towards beta2 glycoprotein 1, and that those which are directed to phospholipids without binding to beta2 glycoprotein 1 may not be pathogenic, but merely epiphenomena. The treatment of this condition has also been changed due to the influence of randomized trials in which heparin or low molecular weight heparin has replaced the use of steroids.

SUMMARY

There are numerous pitfalls in managing this condition. As beta2 glycoprotein 1 antibodies are not usually tested, the condition may be over diagnosed or misdiagnosed. Similarly, the results of treatment are not usually corrected for confounding factors such as fetal chromosomal aberrations. In the absence of other confounding factors low molecular weight heparins are probably the treatment of choice.

"Black swan in the kidney": renal involvement in the antiphospholipid antibody syndrome

The antiphosphospholipid antibody syndrome (APS) describes a clinical entity with recurrent thrombosis, fetal loss, thrombocytopenia in the presence of lupus anticoagulant and/or antibodies to cardiolipin. These antibodies may be associated with connective tissue diseases such as systemic lupus erythematosus (secondary APS) or be found in isolation (primary APS). Renal syndromes increasingly being reported in association with these antibodies include thrombotic microangiopathy, renal vein thrombosis, renal infarction, renal artery stenosis and/or malignant hypertension, increased allograft vascular thrombosis, and reduced survival of renal allografts. Although much has been understood concerning the biology of these antibodies and the pathogenesis of thrombosis, the optimal therapy remains to be elucidated. This article presents a historical review of the renal involvement in the antiphospholipid syndrome and discusses therapeutic options. Further research is needed.

The influence of antiphospholipid antibodies on the pregnancy outcome of patients with recurrent spontaneous abortion

Several therapeutic regimens have been proposed for women with recurrent spontaneous abortion (RSA) and antiphospholipid antibodies (APA). Conflicting results have been reported about women with history of RSA, positive APA, and failure of standard therapy. To evaluate the use of intravenous immunoglobulin in RSA patients with APA and history of treatment failure, we initiated a study with standard therapy (aspirin and low-molecular-weight heparin) and intravenous immunoglobulin. We used an enzyme-linked immunosorbent assay (ELISA) test to screen IgG and IgM anticardiolipin antibodies, and a diluted Russel viper venom time assay for the lupus anticoagulant activity. Altogether, 66 pregnant women with positive APAs at the first visit could be included. Patients with hereditable thrombophilic factors were excluded. After confirmation of the pregnancy, women received a basis immunization of 0.3 g/kg immunoglobulin in a 4-week cycle until the 28th to 32nd week of gestation. All patients received 100 mg/d aspirin and 3,000 anti-Xa U/d certoparin. Among the 66 pregnant women, 17 were persistently autoantibody positive (25.8%), of whom 11 (16.7%) were ACA positive alone, 2 (3%) were lupus anticoagulant positive, and 4 (6.4%) had both antibody types. A total of 49 patients had positive APAs at the initial test, but were negative for ACA and lupus anticoagulant at the second test administered approximately 5 weeks after the start of therapy. We described this group in our following observation as "antibody negative." Sixteen of the 17 autoantibody-positive patients (94.1%) were delivered of live infants compared with 40 patients (81.6%) in the antibody-negative group (odds ratio [OR]: 1.2; 95% CI: 0.98 to 1.4). The overall miscarriage rate was 12.1% and the fetal loss rate was 15.2%. Four patients (25%) in the antibody-positive group developed symptoms of preeclampsia and fetal growth retardation compared with four patients (9.8%) in the antibody-negative group. In conclusion, we see a reduction of the fetal loss rate in patients with RSA and positive APA (5.8%) compared with APA-negative (18.4%) women with the same therapy (OR: 0.3; 95% CI: 0.04 to 2.3).

Pregnancy and lupus nephritis

Family planning and pregnancy are important and usually problematic issues for a young woman with lupus nephritis. Moderate renal insufficiency and previous use of alkylating cytotoxic drugs are associated with decreased fertility. Oral contraceptives containing synthetic estrogens are contraindicated in women with active lupus nephritis, uncontrolled hypertension, history of thromboembolic diseases or high levels of antiphospholipid antibodies. Mild flares of systemic lupus erythematosus (SLE) are common during pregnancy, severe renal flares and permanent impairment of renal function are uncommon. The outlook of pregnancy for women with lupus nephritis is usually favourable if the disease (both renal and nonrenal) has been quiescent for at least 6 months before pregnancy, and if, at conception, serum creatinine is less than 140 micromol/l, proteinuria less than 3 g/24 h and blood pressure controlled. The risk of fetal loss is, however, at least 2-3 times higher than in the normal population and pre-eclampsia, prematurity and fetal growth retardation frequently complicate these pregnancies. Especially poor fetal outcome is associated with antiphospholipid antibodies. Pregnancies in women with lupus nephritis require intense fetal and maternal surveillance.

Antiphospholipid syndrome and recurrent miscarriages

Sixty percent of recurrent spontaneous abortions are unexplained. Antiphospholipid syndrome is a multisystem disease with the predominant features of venous and arterial thrombosis, recurrent pregnancy loss, foetal death and the presence of antiphospholipid antibodies. Many epidemiological studies focus on antiphospholipid autoantibodies syndrome (APS) as a cause of recurrent spontaneous abortion (RSA). It is found that 7-25% of RSA would have APS as the main risk factor. 'Association not being synonymous with cause', the proportion of abortions due to the APS is difficult to estimate for several reasons: definition of recurrent abortion is variable, the assays for antiphospholipid antibodies are not well standardised, inclusion of patients in the study group according to the antibodies titre is author dependent. Recent studies suggest association of antiphospholipid antibodies syndrome not only with recurrent abortions but also with infertility. New mechanisms are described by which antiphospholipid antibodies could cause placental thrombosis and infarction, acting directly on the surface anticoagulant expressed on trophoblastic cells. Only lupus anticoagulant (LA) and anticardiolipin antibodies (aCL) assays are sufficiently standardised to be usable in routine. Testing for other antiphospholipid antibodies (aPLs) should remain investigational. Several treatments have been proposed: low doses of aspirin, low or immunosuppressive doses of corticosteroids, and preventive or effective dose of heparin, intravenous immunoglobulin.

Treatment of the antiphospholipid antibody syndrome: progress in the last five years?

The gold standard for treatment of the antiphospholipid antibody syndrome (APS) after thrombosis remains high-intensity warfarin, and, in pregnancy, heparin and aspirin. Exciting developments include the potential role of hydroxychloroquine as a prophylactic drug, stem cell transplantation, and B-cell tolerance. Animal models appear to be a fruitful "proving ground" of new therapies. The introduction of revised classification criteria for APS should aid in appropriate characterization of, and selection of, patients for clinical trials.

Cytomegalovirus immune globulin intravenous (human) administration modulates immune response to alloantigens in sensitized renal transplant candidates

One of the important parameters for prolonged waiting time for potential renal transplant recipients is the presence of preformed antibodies to human leucocyte antigen (HLA) antigens, which is often caused by previous transplants, pregnancy or transfusions. In vivo administration of specific and unselected polyclonal intravenous immunoglobulin (IVIGs) preparations have been shown to inhibit anti-HLA alloantibodies in highly sensitized patients. We sought to determine whether Cytogam (Medimmune Inc., Gaithersburg, MD, USA), a hyperimmune anticytomegalovirus immunoglobulin would (1) effect either in vitro or in vivo alloreactivity, and (2) whether Cytogam therapy could reduce the titre of preformed anti-HLA antibodies in highly sensitized patients. Alloreactivity was assessed by mixed lymphocyte reaction (MLR) and cytotoxic T lymphocyte (CTL) assay. A complement dependent microlymphocytotoxicity assay was done to assess for panel reactive antibody (PRA) status and the presence of anti-idiotypic antibodies in the Cytogam preparation. The MLR was inhibited by Cytogam in vitro in a dose-dependent fashion ranging from 31-92%. Significant inhibition of the MLR responses was not observed in recipients who received Cytogam in vivo (50 mg/kg). This could be a result of adminstration of a low dose of IVIG. However, CTL activity against the alloantigens in all individuals assessed was significantly inhibited after in vivo administration of Cytogam. Three of five individuals experienced a decrease of 5-32% in the PRA status at 4 weeks post administration of Cytogam. Cytogam also blocked the anti-HLA antibody titres in a microlymphocytotoxicity assay, suggesting the presence of anti-idiotypic antibodies. Our study was based on a single prophylactic dose of Cytogam (50 mg/kg), however, higher dose administration could be feasible by removing more fluid at dialysis, but should be given intradialytically to avoid volume overload. Overall, our results suggest that Cytogam can modulate the in vivo and in vitro T cell responses against the alloantigens.

[Polyvalent intravenous immunoglobulins in systemic lupus]

PURPOSE

To evaluate intravenous immunoglobulins (IVIG) treatment, which is immunomodulatory but not immunosuppressive, in SLE.

MAIN ISSUES

IVIG indications in SLE could be categorized as already validated as for chronic polyradiculoneuropathy or thrombocytopenia; failure of classical treatment in threatening active disease; undetermined manifestation as reactive hemophagocytic syndrome which could be both disease-specific or iatrogenic, infection-related. To date, no published study has firmly established the efficacy of IVIG in SLE.

CONCLUSION

IVIG therapy in SLE should be evaluated in prospective trials.

Recurrent pregnancy loss: an update

This review highlights recent studies that investigate causes and treatments for recurrent pregnancy loss. Generally the causes of recurrent pregnancy loss are classified as genetic, endocrinologic, anatomic, immunologic, microbiologic, and environmental. The majority of recent work has focused on potential autoimmune and alloimmune causes; however, controversy still exists over appropriate testing and treatment. Reports have investigated the potential associations between autoimmune factors (antithyroid antibodies and antiphospholipid antibodies) and alloimmune factors (natural killer cells, cytotoxic T cells, and embryotoxic factors) and recurrent pregnancy loss. Increasingly, clinical reports are suggesting intravenous immunoglobulin as a potential treatment for these immunologic problems. Several lines of investigation have suggested certain hypercoagulable states as causative of recurrent pregnancy loss. New studies relating recurrent pregnancy loss to endocrinologic aberrations (hyperprolactinemia and hyperandrogenism) as well as social/environmental factors (stress, caffeine use, tobacco use, human immunodeficiency virus, and history of induced abortion) have been made. A summary of proposed evaluation and treatment options is presented.

Maternal Th1- and Th2-type reactivity to placental antigens in normal human pregnancy and unexplained recurrent spontaneous abortions

Spontaneous abortion is the most common complication of pregnancy, but the etiology of a significant proportion of abortions is still unknown. We have examined the production of Th1- and Th2-type cytokines by women with unexplained recurrent spontaneous abortion (RSA) since it appears that successful murine pregnancy occurs in a Th2-dominant situation and that Th1-type immunity is associated with pregnancy failure. We have compared maternal reactivity toward placental antigens in women with a history of successful pregnancy with that in women with a history of RSA. This was done by coculturing maternal peripheral blood mononuclear cells (PBMC) with autologous placental cells and also by stimulating maternal PBMC with antigens from a choriocarcinoma cell line of trophoblastic origin. We detected significantly greater levels of the Th2 cytokines IL-6 and IL-10 in normal pregnancy compared to unexplained RSA and significantly higher levels of the Th1 cytokine IFN-gamma in RSA compared to normal pregnancy. These results suggest that women with normal pregnancy have a higher Th2 bias, while women with a history of RSA evince a bias toward Th1-type reactivity.