Changes in immune activation markers during pregnancy and postpartum

Modulation of cell-mediated immunity during pregnancy in wild bonobos

During pregnancy, the mammalian immune system must simultaneously protect against pathogens while being accommodating to the foreign fetal tissues. Our current understanding of this immune modulation derives predominantly from industrialized human populations and laboratory animals. However, their environments differ considerably from the pathogen-rich, resource-scarce environments in which pregnancy and the immune system co-evolved. For a better understanding of immune modulation during pregnancy in challenging environments, we measured urinary neopterin, a biomarker of cell-mediated immune responses, in 10 wild female bonobos (Pan paniscus) before, during and after pregnancy. Bonobos, sharing evolutionary roots and pregnancy characteristics with humans, serve as an ideal model for such investigation. Despite distinct environments, we hypothesized that cell-mediated immune modulation during pregnancy is similar between bonobos and humans. As predicted, neopterin levels were higher during than outside of pregnancy, and highest in the third trimester, with a significant decline post-partum. Our findings suggest shared mechanisms of cell-mediated immune modulation during pregnancy in bonobos and humans that are robust despite distinct environmental conditions. We propose that these patterns indicate shared immunological processes during pregnancy among hominins, and possibly other primates. This finding enhances our understanding of reproductive immunology.

Immune checkpoint therapy for solid tumours: clinical dilemmas and future trends

Immune-checkpoint inhibitors (ICBs), in addition to targeting CTLA-4, PD-1, and PD-L1, novel targeting LAG-3 drugs have also been approved in clinical application. With the widespread use of the drug, we must deeply analyze the dilemma of the agents and seek a breakthrough in the treatment prospect. Over the past decades, these agents have demonstrated dramatic efficacy, especially in patients with melanoma and non-small cell lung cancer (NSCLC). Nonetheless, in the field of a broad concept of solid tumours, non-specific indications, inseparable immune response and side effects, unconfirmed progressive disease, and complex regulatory networks of immune resistance are four barriers that limit its widespread application. Fortunately, the successful clinical trials of novel ICB agents and combination therapies, the advent of the era of oncolytic virus gene editing, and the breakthrough of the technical barriers of mRNA vaccines and nano-delivery systems have made remarkable breakthroughs currently. In this review, we enumerate the mechanisms of each immune checkpoint targets, associations between ICB with tumour mutation burden, key immune regulatory or resistance signalling pathways, the specific clinical evidence of the efficacy of classical targets and new targets among different tumour types and put forward dialectical thoughts on drug safety. Finally, we discuss the importance of accurate triage of ICB based on recent advances in predictive biomarkers and diagnostic testing techniques.

Low on-treatment levels of serum soluble CD8 (sCD8) predict better outcomes in advanced non-small cell lung cancer patients treated with atezolizumab

BACKGROUND

Immunotherapy has changed the paradigm of treating non-small cell lung cancer (NSCLC). But, selecting patients who will achieve long-term benefits from treatment remains unsatisfactory. Here, we investigated the possible use of the soluble form of CD8 antigen (sCD8) in predicting durable disease control after PD-1/PD-L1 blockade. CD8 is a marker of the cytotoxic T lymphocytes. Its soluble form (sCD8) is secreted under activation of the immune system but also has immunosuppressive properties. The data about serum sCD8 in patients dosed with anti-PD-1/PD-L1 drugs are lacking.

METHODS AND RESULTS

We included 42 NSCLC patients and collected samples at baseline and for the first 3 months of atezolizumab immunotherapy. The serum sCD8 concentrations were measured with the ELISA kit and correlated with treatment outcomes. Patients with durable (≥ 12 months) disease control presented lower serum sCD8 than those without long-term benefits. The sCD8 levels measured at the end of cycle 2 (sCD8.2) were the earliest time point that successfully differentiated patients (3.76 vs. 9.68 ng/mL, respectively, p < 0.001). Individuals with low sCD8.2 (≤ 4.09 ng/mL) presented longer progression-free survival (HR = 0.061, p < 0.001) and overall survival (HR = 0.104, p < 0.05) compared to individuals with high sCD8.2 (median values unreached vs. 4.4 months and 14.4 months for PFS and OS, respectively).

CONCLUSIONS

Serum sCD8 could be an early biomarker of durable disease control after anti-PD-L1 treatment. Higher sCD8 in patients with worse outcomes could suggest the inhibitory effect of sCD8 on cytotoxic T-cells activation.

Immunotherapy for cancer treatment during pregnancy

Immunotherapy has greatly improved outcomes for subgroups of patients with cancer. As indications keep expanding, there is an unmet need to gain a better understanding of the effect of these therapies on pregnancy and fertility. During pregnancy, substantial adaptations occur in the maternal immune system to maintain protection against pathogens while avoiding detrimental reactions to the semi-allogeneic fetus. The pathways involved in the establishment of this fetomaternal tolerance can be hijacked by cancers. Immunotherapies that target these inhibitory pathways, or that directly interact with the regulatory immune cells involved in tolerance mechanisms, might therefore result in complications during pregnancy. Similarly, by activating the patient's immune system with immunotherapy, a broad range of immune-related adverse events can occur that could negatively affect the fetus or impede a future desired pregnancy. This Review summarises preclinical and clinical data related to the use of immunotherapy during pregnancy, including all approved immune checkpoint inhibitors, recombinant cytokines, cell therapies, vaccines, and immunomodulatory drugs.

The role of CD38 in HIV infection

The widely-expressed molecule CD38 is a single-stranded type II transmembrane glycoprotein that is mainly involved in regulating the differentiation and activation state of the cell. CD38 has broad and complex functions, including enzymatic activity, intercellular signal transduction, cell activation, cytokine production, receptor function and adhesion activity, and it plays an important role in the physiological and pathological processes of many diseases. Many studies have shown that CD38 is related to the occurrence and development of HIV infection, and CD38 may regulate its progression through different mechanisms. Therefore, investigating the role of CD38 in HIV infection and the potential signaling pathways that are involved may provide a new perspective on potential treatments for HIV infection. In the present review, the current understanding of the roles CD38 plays in HIV infection are summarized. In addition, the specific role of CD38 in the process of HIV infection of human CD4⁺ T lymphocytes is also discussed.

Comparison of early pregnancy serum concentration of neopterin, neopterin/creatinine ratio, C-reactive protein, and chitotriosidase, in pregnant women with birth at term and spontaneous preterm birth

Inflammatory mechanisms are involved in achieving a normal pregnancy and in the development of certain pregnancy complications. These changes are more intense in pregnant women that suffer of pregnancy complications, such as spontaneous preterm birth (SPB). This study compared the course of inflammatory markers (IM) [neopterin (Neo), neopterin/creatinine ratio (Neo/Cre), C-reactive protein (CRP), and chitotriosidase (Chito)] serum concentration in the early pregnancy of women with birth at term (BT) and preterm birth (PB). IM concentration was measured in 90 sera sampled from 45 pregnancies with BT and 30 sera from 15 pregnancies with PB. Two sera were sampled from each pregnant woman: one in the first trimester and another one in the second trimester. Early pregnancy IM concentration showed a direct correlation with gestational age: Neo (rho=0.262, P=0.004), Neo/Cre (rho=0.372, P<0.001), CRP (rho=0.187, P=0.041), and Chito (rho=0.039, P=0.66). The correlation was present in both categories of patients with BT and PB. Patients with PB before 34 week of pregnancy (wp) and 32 wp showed higher Neo and Neo/Cre concentration than BT patients. A significant association was found between the risk of PB before 34 wp, PB before 32 wp, and Neo concentration (PB <34 wp: odds ratio (OR) =5.13, P=0.035) (PB <32 wp: OR=8.2, P=0.020) and, respectively, Neo/Cre concentration (PB <34 wp: OR=5.29, P=0.015) (PB <32 wp: OR=9.25, P=0.006). No association between CRP or Chito and PB age was found. IM concentration correlates with the gestational age at the time of blood sampling. Increased Neo and Neo/Cre concentration are associated with PB. Further studies are needed to evaluate the usefulness of these markers in clinical practice.

Postpartum histoplasmosis in an HIV-negative woman: a case report and phylogenetic characterization by internal transcribed spacer region analysis

The present report describes the first case of postpartum disseminated histoplasmosis in a 24-year-old HIV-negative woman. On the tenth day after vaginal delivery, the patient presented with dyspnea, fever, hypotension, tachycardia, and painful hepatomegaly. Yeast-like Histoplasma capsulatum features were isolated in the buffy coat. The phylogenetic analysis demonstrated that the fungal isolate was similar to other H. capsulatum isolates identified in HIV patients from Ceará and Latin America. Thus, histoplasmosis development in individuals with transitory immunosuppression or during the period of immunological recovery should be carefully examined.

Brief Report: Markers of Spontaneous Preterm Delivery in Women Living With HIV: Relationship With Protease Inhibitors and Vitamin D

BACKGROUND

Women living with HIV (WLHIV) have increased risk of spontaneous preterm delivery (SPTD). We sought to identify plasma predictors of SPTD and their correlations with factors that increase the risk of SPTD, such as vitamin D deficiency and use of protease inhibitors.

DESIGN

Plasma was obtained from 103 WLHIV with SPTD (≤35 weeks gestation) and 205 controls with term deliveries (TDs; ≥37 weeds) matched to cases 2:1 by race and gestational age at blood draw. TNFα, IFNγ, IL6, IL8, IL1β, IL18, IL17, granulocyte colony stimulating factor (GCSF), MCP1, IP10, sIL2Rα, sCD14, vascular endothelial factor a, monocyte colony stimulation factor, GROα, MMP9, IL10, TGFβ, sCTLA4, and eicosanoids were compared between cases adjusting for known SPTD risk factors.

RESULTS

Participants had similar demographic characteristics, but cases had higher plasma HIV RNA, lower CD4 cells, and more advanced HIV disease compared with controls. High sIL2Rα was associated with increased risk of SPTD. High sCD14, GCSF, PGF2α, and 5-HEPE were marginally associated with increased risk of SPTD. Women who initiated protease inhibitors-containing antiretroviral treatment before or during the first trimester had higher levels of GCSF and 5-HEPE compared with women without such exposure before plasma collection. Vitamin D insufficiency was associated with higher inflammatory sCD14 and PGF2α, and lower anti-inflammatory 5-HEPE.

CONCLUSIONS

The best plasma predictor of SPTD in WLHIV was sIL2Rα, a marker of T-cell activation. Markers of monocyte activation and eicosanoids were marginally increased in WLHIV and SPTD, suggesting that they may also play a role in the pathogenesis of this disorder.

Microbial Translocation and Immune Activation in HIV-1 Infected Pregnant Women

BACKGROUND

Immune Activation (IA) has been previously documented in both pregnant (PG) and non-PG HIV-1 infected (HIV+) women as well as in HIV- uninfected PG women; the latter as a result of the fetal allograft. To determine whether the combined effects of HIV and pregnancy result in increased IA and whether IA is associated with Microbial Translocation (MT), we performed a prospective, longitudinal, controlled study during pregnancy and the postpartum (PP) period.

METHODS

HIV+ PG women had biomarkers of IA and MT tested at 12-20 weeks (T1), and 24-36 weeks (T2) of pregnancy and at 6-8 weeks Postpartum (T3). HIV+, non-PG women were tested at comparable time points. HIV- PG women were tested at T1 only. HIV+ women were not started on antiretroviral therapy (ART) until T1. Biomarkers of IA assessed included: CD4DR+, CD4CD38+, CD4DR+CD38+, CD8DR+, CD8CD38+, and CD8DR+CD38+. Biomarkers of MT included LPS, sCD14, and 16SrDNA.

RESULTS

30 HIV+PG women, 18 HIV+ non-PG and 10 HIV-PG were enrolled. In the HIV+ women, there were no differences in median age, viral load, % or absolute CD4 at entry. Significant differences between T1 and T2 and between T1 and T3 were noted in CD8DR+CD38+ in HIV+PG women after ART. CD4DR+, CD4DR+CD38+, and CD8DR+ decreased post ART in HIV+PG women but a decline in IA was less evident in HIV+ non-PG. LPS decreased post ART by T3 in both HIV+PG and HIV+ non-PG groups; 16SrDNA was elevated at all time points in both groups when compared to control values, and declined post ART in the HIV+PG group. A subgroup of HIV-PG at T1 had IA and MT as evidenced by several IA markers and increased LPS.

CONCLUSION

The degree of IA and MT was similar among HIV+PG and HIV+ non-PG women followed longitudinally. There was no incremental increase due to the combined effects of HIV and pregnancy. Several markers of IA and MT (LPS, 16SrDNA) decreased post ART. IA and MT occurred in a subgroup of HIV-PG women during the 1st trimester. Further study must be done to confirm whether MT consistently occurs in some healthy women during PG.

The psychoneuroimmunology of pregnancy

Pregnancy is associated with a number of significant changes in maternal physiology. Perhaps one of the more notable changes is the significant alteration in immune function that occurs during pregnancy. This change in immune function is necessary to support a successful pregnancy, but also creates a unique period of life during which a female is susceptible to disease and, as we'll speculate here, may also contribute to mental health disorders associated with pregnancy and the postpartum period. Here, we review the known changes in peripheral immune function that occur during pregnancy and the postpartum period, while highlighting the impact of hormones during these times on immune function, brain or neural function, as well as behavior. We also discuss the known and possible impact of pregnancy-induced immune changes on neural function during this time and briefly discuss how these changes might be a risk factor for perinatal anxiety or mood disorders.

Maternal Zika Virus Disease Severity, Virus Load, Prior Dengue Antibodies, and Their Relationship to Birth Outcomes

Background

Congenital Zika virus (ZIKV) syndrome is a newly identified condition resulting from infection during pregnancy. We analyzed outcome data from a mother-infant cohort in Rio de Janeiro in order to assess whether clinical severity of maternal ZIKV infection was associated with maternal virus load, prior dengue antibodies, or abnormal pregnancy/infant outcomes.

Methods

A clinical severity assessment tool was developed based on duration of fever, severity of rash, multisystem involvement, and duration of symptoms during ZIKV infection. ZIKV-RNA load was quantified by polymerase chain reaction (PCR) cycles in blood/ urine. Dengue immunoglobulin G (IgG) antibodies were measured at baseline. Adverse outcomes were defined as fetal loss or a live infant with grossly abnormal clinical or brain imaging findings. Regression models were used to study potential associations.

Results

131 ZIKV-PCR positive pregnant women were scored for clinical disease severity, 6 (4.6%) had mild disease, 98 (74.8%) had moderate disease, and 27 (20.6%) severe manifestations of ZIKV infection. There were 58 (46.4%) abnormal outcomes with 9 fetal losses (7.2%) in 125 pregnancies. No associations were found between: disease severity and abnormal outcomes (P = .961; odds ratio [OR]: 1.00; 95% confidence interval [CI]: 0.796-1.270); disease severity and viral load (P = .994); viral load and adverse outcomes (P = .667; OR: 1.02; 95% CI: 0.922-1.135); or existence of prior dengue antibodies (88% subjects) with severity score, ZIKV-RNA load or adverse outcomes (P = .667; OR: 0.78; 95% CI: 0.255-2.397).

Conclusions

Congenital ZIKV syndrome does not appear to be associated with maternal disease severity, ZIKV-RNA load at time of infection or existence of prior dengue antibodies.

Hyperthyroidism During Pregnancy: Etiology, Diagnosis and Management

Pregnancy has marked effects on thyroid physiology and autoimmune thyroid disease tends to ameliorate through gestation due to the general immunosuppression seen in pregnancy. There is a need for trimester-specific thyroid hormone reference ranges. Hyperthyroidism in pregnancy – usually due to Graves' disease – is not common but, if the patient is compliant, a good outcome can be expected for both mother and child if treatment with anti-thyroid drugs (propylthiouracil is preferred) is instituted. Thyroid-stimulating hormone receptor antibody should be measured at 36 weeks in such patients in order to predict the possibility of neonatal hyperthyroidism. Transient gestational hyperthyroidism is often associated with hyperemesis gravidarum and thyroid function should be checked in patients severely affected by this condition. Radioiodine therapy is contraindicated in pregnancy but thyroid surgery may be performed safely in the second trimester. Autoimmune thyroiditis and Graves’ hyperthyroidism occur quite commonly in postpartum women.

Early pregnancy serum neopterin concentrations predict spontaneous preterm birth in asymptomatic pregnant women

OBJECTIVE

To investigate if early pregnancy serum neopterin concentrations (EPSN) could predict spontaneous preterm birth (SPB).

METHODS

EPSN was measured in 92 sera collected from 46 pregnant women with birth at term and 40 sera from 20 pregnant women with preterm birth. Two sera were collected for each case: in the first and early second trimester.

RESULTS

EPSN concentrations correlate with gestational age (ρ=0.275, P=0.001), a correlation which was present in both groups: term and preterm birth. EPSN were higher in pregnancies with SPB compared with normal pregnancies (6.27±1.03 vs. 6.04±0.15, P=0.039). Patients with SPB showed a considerable increase of EPSN in the second trimester compared with patients with birth at term (7.30±1.53 vs. 6.16±0.23, P=0.043). A sharper increase was found in the group with SPB before 32 weeks of pregnancy (wp) (9.83±4.36 vs. 6.16±0.23, P=0.016). Pregnant women with an early second trimester serum neopterin value of above 8 nmol/L are associated with a risk of SPB before 32 wp (odds ratio=14.4, P=0.01) and of SPB before 34 wp (odds ratio=3.6, P=0.05), respectively.

CONCLUSIONS

EPSN increases with the gestational age and predicts SPB in asymptomatic pregnant women.

Understanding and Managing Pregnancy in Patients with Lupus

Systemic lupus erythematosus (SLE) is a chronic, multisystemic autoimmune disease that occurs predominantly in women of fertile age. The association of SLE and pregnancy, mainly with active disease and especially with nephritis, has poorer pregnancy outcomes, with increased frequency of preeclampsia, fetal loss, prematurity, growth restriction, and newborns small for gestational age. Therefore, SLE pregnancies are considered high risk condition, should be monitored frequently during pregnancy and delivery should occur in a controlled setting. Pregnancy induces dramatic immune and neuroendocrine changes in the maternal body in order to protect the fetus from immunologic attack and these modifications can be affected by SLE. The risk of flares depends on the level of maternal disease activity in the 6–12 months before conception and is higher in women with repeated flares before conception, in those who discontinue useful medications and in women with active glomerulonephritis at conception. It is a challenge to differentiate lupus nephritis from preeclampsia and, in this context, the angiogenic and antiangiogenic cytokines are promising. Prenatal care of pregnant patients with SLE requires close collaboration between rheumatologist and obstetrician. Planning pregnancy is essential to increase the probability of successful pregnancies.

Human breast milk concentration of neopterin at various stages of lactation and during a single feeding

The aim of this work was to determine the physiological level of neopterin in human breast milk, and to study its variability depending on the duration of a single feeding and the lactation stage. Breast milk samples from 74 women were collected between 2 and 4 days after delivery, and at 15, 30, and 90 days after delivery. Additionally, breast milk samples from eight women were collected before and after 7 and 15 min of breastfeeding. The concentration of neopterin in breast milk was determined by an immunoenzymatic assay. The range of breast milk neopterin concentration at various stages of lactation amounted to 15.4–19.2 nmol/L at 2–4 days after delivery, 20.2–23.0 nmol/L at day 15, 20.8–24.5 nmol/L at day 30, and 16.9–20.4 nmol/L at day 90. The level of neopterin 2–4 days after delivery was significantly lower than that at days 15 and 30; moreover, the concentration of neopterin at day 30 was significantly higher than that at day 90. No significant differences were documented between neopterin concentrations at various phases of a single feeding. While the breast milk concentration of neopterin changes depending on the stage of lactation, it remains stable throughout a single feeding.

Efficacy of screening immune system function in at-risk newborns

This paper explores the introduction of a screening test to highlight impaired immune system status for newborn infants and its efficacy as a preventative clinical measure. Moreover, it is suggested that screening of the infantile immune system has the potential to highlight susceptibility to a range of infant and childhood diseases, bestowing an opportunity to introduce early intervention to reduce the incidence of these diseases. Development of the neonatal immune system is an important health issue, implicated in many childhood problems such as allergies, infection, and autoimmunity. The neonate has a limited immune system and ability to combat bacteria. Depleted levels of the tripeptide reduced glutathione (GSH) have been linked to numerous conditions and its intracellular level is acknowledged as an indicator of immune system function. Introduction of an immune system screening programme for infants is formally reviewed and assessed. Several benefits are reported in the treatment of impaired immune systems, a trial screening programme is proposed for at-risk infants to gather further evidence as to its efficacy. Infants at risk of impaired immune system function include cystic fibrosis, premature infants, and low birth weight infants. The interventions include breastfeeding, milk banks, and appropriate formula to support the immune system.

Immune activation markers in peripartum women in Botswana: association with feeding strategy and maternal morbidity

Hormone levels shift the immune state in HIV-uninfected pregnant and breastfeeding women away from Th₁ responses and toward regulation to permit fetal tolerance. Limited data exist on inflammation during pregnancy or postpartum in HIV-infected women, though certain inflammatory markers are associated with adverse health outcomes among HIV-infected persons.

We measured hsCRP, D-dimer, IFN-γ, IL-6, IL-10 and TNF-α at 34 weeks gestation and six months postpartum in HIV-infected women from the Botswana Mashi PMTCT trial who were randomized to breastfeeding or formula-feeding. Differences in inflammatory markers between gestation and postpartum periods, and by randomized feeding method, were estimated using generalized estimating equations, adjusting for baseline plasma HIV-1 viral load, CD4 count, calendar time, and antiretroviral treatment status. Additionally, we studied the association between marker concentrations at six months postpartum and major adverse clinical events over the following 4.5 years, using case-cohort sampling and adjusted Cox proportional hazards models.

In 86 breastfeeding and 75 formula-feeding women, hsCRP and D-dimer decreased significantly between 34 weeks gestation and six months postpartum, while IFN-γ increased. There was no significant association between inflammatory marker change and randomized feeding method after adjusting for multiple comparisons and removing outliers. In univariate analysis, TNF-α, D-dimer, and IFN-γ concentrations at six months postpartum were significant predictors of subsequent clinical events, and TNF-α remained significant in multivariate analysis (HR = 4.16, p = 0.001).

In young HIV-infected women in Botswana inflammatory marker concentrations did not differ significantly between women who breast- vs. formula-fed. However, postpartum TNF-α level was predictive of subsequent adverse clinical event.

Level of CD8 T Lymphocytes Activation in HIV-Infected Pregnant Women: In the Context of CD38 and HLA-DR Activation Markers

Background. To date the effect of pregnancy on the immune activation of CD8 T cells that may affect HIV disease progression has not been well studied and remains unclear. Objective. To determine the effect of pregnancy on CD8 T lymphocyte activation and its relationship with CD4 count in HIV infected pregnant women. Study Design. Case control. Study Site. AMPATH and MTRH in Eldoret, Kenya. Study Subjects. Newly diagnosed asymptomatic HIV positive pregnant and nonpregnant women with no prior receipt of antiretroviral medications. Study Methods. Blood samples were collected from the study participants and levels of activated CD8 T lymphocytes (CD38 and HLA-DR) were determined using flow cytometer and correlated with CD4 counts of the study participants. The descriptive data focusing on frequencies, correlation, and cross-tabulations was statistically determined. Significance of the results was set at P < 0.05. Results. HIV positive pregnant women had lower activated CD8 T lymphocyte counts than nonpregnant HIV positive women. Activated CD8 T lymphocyte counts were also noted to decrease in the second and third trimesters of pregnancy. Conclusion. Pregnancy has a significant suppression on CD8+ T lymphocyte immune activation during HIV infections. Follow-up studies with more control arms could confirm the present study results.

Hormonal influences on neuroimmune responses in the CNS of females

Particular reproductive stages such as lactation impose demands on the female. To cope with these demands, her physiology goes through numerous adaptations, for example, attenuation of immune and stress responses. Hormonal fluctuation during lactation exerts a strong influence, inducing neuroplasticity in the hypothalamus and extrahypothalamic regions, and diminishing the stress and inflammatory responses. Thus, hormones confer decreased vulnerability to the female brain. This mini-review focuses on the adaptations of the immune and stress response during maternity, and on the neuroprotective actions of progesterone and prolactin and their effects on inflammation. The importance of pregnancy and lactation as experimental models to study immune responses and disease is also highlighted.

Pathogenesis of hepatitis C during pregnancy and childhood

The worldwide prevalence of HCV infection is between 1% and 8% in pregnant women and between 0.05% and 5% in children. Yet the pathogenesis of hepatitis C during pregnancy and in the neonatal period remains poorly understood. Mother-to-child transmission (MTCT), a leading cause of pediatric HCV infection, takes place at a rate of <10%. Factors that increase the risk of MTCT include high maternal HCV viral load and coinfection with HIV-1 but, intriguingly, not breastfeeding and mode of delivery. Pharmacological prevention of MTCT is not possible at the present time because both pegylated interferon alfa and ribavirin are contraindicated for use in pregnancy and during the neonatal period. However, this may change with the recent introduction of direct acting antiviral agents. This review summarizes what is currently known about HCV infection during pregnancy and childhood. Particular emphasis is placed on how pregnancy-associated immune modulation may influence the progression of HCV disease and impact MTCT, and on the differential evolution of perinatally acquired HCV infection in children. Taken together, these developments provide insights into the pathogenesis of hepatitis C and may inform strategies to prevent the transmission of HCV from mother to child.

Hyperthyroidism during pregnancy: etiology, diagnosis and management

Pregnancy has marked effects on thyroid physiology and autoimmune thyroid disease tends to ameliorate through gestation due to the general immunosuppression seen in pregnancy. There is a need for trimester-specific thyroid hormone reference ranges. Hyperthyroidism in pregnancy - usually due to Graves' disease - is not common but, if the patient is compliant, a good outcome can be expected for both mother and child if treatment with anti-thyroid drugs (propylthiouracil is preferred) is instituted. Thyroid-stimulating hormone receptor antibody should be measured at 36 weeks in such patients in order to predict the possibility of neonatal hyperthyroidism. Transient gestational hyperthyroidism is often associated with hyperemesis gravidarum and thyroid function should be checked in patients severely affected by this condition. Radioiodine therapy is contraindicated in pregnancy but thyroid surgery may be performed safely in the second trimester. Autoimmune thyroiditis and Graves' hyperthyroidism occur quite commonly in postpartum women.

Interaction of pregnancy and autoimmune rheumatic disease

During pregnancy, the fetus represents a natural allograft that is not normally rejected. While the maternal immune system retains the ability to respond to foreign antigens, tolerance mechanisms are up-regulated to protect the fetus from immunologic attacks by the mother. The profound immunologic adaptations during and after pregnancy do influence maternal autoimmune rheumatic diseases in several ways. One is triggering the onset of a rheumatic disease in the post partum period, the other influencing disease activity of established rheumatic disease. The review will discuss the mechanisms of increased susceptibility of rheumatoid arthritis (RA) in the first year post partum with a specific emphasis on the role of fetal cells or antigens persisting in the maternal circulation (so called microchimerism). Furthermore, the different influences of pregnancy on established rheumatic diseases will be highlighted. A marked beneficial effect of pregnancy is observed on RA whereas several other rheumatic diseases as ankylosing spondylitis (AS) and systemic lupus erythematosus (SLE) show either no particular effect or an aggravation of symptoms during pregnancy. Differences emerging in regard to modulation of disease symptoms during pregnancy seem related to response to hormones, the type of cytokine profile and immune response prevailing as well as further downstream interactions of molecular pathways that are important in disease pathogenesis.

Dynamics of regulatory T-cells during pregnancy: effect of HIV infection and correlations with other immune parameters

Objectives

Regulatory T cells (Treg) increase in the context of HIV infection and pregnancy. We studied Treg subpopulations in HIV-infected and uninfected women during pregnancy and their relationship with inflammation, activation and cell-mediated immunity (CMI).

Design and Methods

Blood obtained from 20 HIV-infected and 18 uninfected women during early and late gestation was used to measure Treg and activated T cells (Tact) by flow cytometry; plasma cytokines and inflammatory markers by ELISA and chemoluminescence; and CMI against varicella-zoster virus (VZV) by lymphocyte proliferation.

Results and Conclusions

Compared with uninfected women, HIV-infected participants had higher frequencies of Treg subpopulations in early pregnancy, including CD4+CD25+FoxP3+%, CD8+CD25+FoxP3+%, CD4+TGFβ+% and CD4+IL10+%. In contrast, Treg frequencies were lower during late pregnancy in HIV-infected compared with uninfected women, including CD8+TGFβ+%, CD4+CTLA4+% and CD8+CTLA4+%. VZV-CMI, which was lower in HIV-infected compared with uninfected pregnant women, was inversely correlated with CD4+FoxP3+%, CD8+FoxP3+% and CD8+TGFβ+% in HIV-infected, but not in uninfected pregnant women. β_2-microglobulin, neopterin, IL1, IL4, IL8, IL10, IFNγ and TNFα plasma concentrations as well as Tact were higher in HIV-infected compared with uninfected women throughout pregnancy. In HIV-infected, but not in uninfected women, inflammatory, Th1, Th2 and regulatory cytokines increased with higher Treg%, suggesting that inflammation and regulation have a common pathophysiologic origin in the context of HIV infection. In HIV-infected and more commonly in uninfected pregnant women, higher Treg% correlated with lower Tact%. We conclude that Treg have different dynamics during pregnancy in HIV-infected and uninfected women. Higher levels of inflammatory cytokines and lower Treg% during late pregnancy in HIV-infected women may contribute to their increased incidence of maternal-fetal morbidity.

Maternal outcomes after HAART for the prevention of mother-to-child transmission in HIV-infected women in Brazil

BACKGROUND

Information is lacking on outcomes in HIV-infected Brazilian women with CD4(+) T-cell counts >200 cells/mm(3) who initiate HAART for the prevention of mother-to-child transmission, and discontinue after delivery.

METHODS

Clinical event rates after postpartum HAART discontinuation were calculated for all WHO stage 2-3 events, as well as for HIV progression warranting HAART re-initiation, defined by a WHO stage 4 event and/or CD4(+) T-cell decrease to ≤200 cells/mm(3). Predictors of the WHO stage 2-3 events and HIV progression outcomes were evaluated with Cox's proportional hazards models.

RESULTS

A total of 120 women were followed for a mean of 1.5 years after delivery. Overall, 26 women had 30 events as follows: 20 developed WHO stage 2-3 events, yielding an incidence rate of 13/100 person-years (PY; 95% CI 8-20); 10 developed HIV progression requiring HAART re-initiation (incidence ratio 6/100 PY, 95% CI 3-11). Among progressors, a single woman developed a WHO stage 4 clinical event and the remainder had CD4(+) T-cell decreases. Women who had baseline CD4(+) T-cell counts between 200-500 cells/mm(3) had a hazard ratio for WHO stage 2-3 events of 2.5 compared to women with baseline ≥500 cells/mm(3) (95% CI 1.0-6.3; P=0.05). The only significant predictor of HIV progression was baseline CD4(+) T-cell count (hazard ratio 0.99, 95% CI 0.98-0.99; P=0.02).

CONCLUSIONS

In this observational study, a baseline CD4(+) T-cell count <500 cells/mm(3) was associated with an increased risk of postpartum WHO stage 2-3 clinical events and HIV disease progression. Randomized studies are needed to further evaluate the effect of postpartum treatment discontinuation on maternal health.

Correlation of immune activation during late pregnancy and early postpartum with increases in plasma HIV RNA, CD4/CD8 T cells, and serum activation markers

A previously observed rise in the plasma viral load postpartum in both treated and untreated HIV-positive women remains unexplained. Virological and immunological markers were evaluated in HIV-negative controls and HIV-positive pregnant women with and without antiretroviral treatment. Plasma HIV RNA, CD4/CD8 T cells, and serum activation markers were sequentially measured during the third trimester, at delivery, and 2 to 8 weeks postpartum in a cohort of HIV-positive pregnant women (n = 96) enrolled in a maternal-fetal HIV transmission study and a control group of HIV-negative pregnant women (n = 28). Mean plasma HIV RNA (P = 0.003) increased from delivery to postpartum, and mean CD4 T cells (P = 0.002) and serum β2-microglobulin (P < 0.0001) increased from the third trimester through postpartum among the HIV-positive women. Mean CD8 T cells increased from the third trimester through postpartum in women receiving zidovudine (ZDV) and in those not treated (P < 0.05) but remained stable in those on highly active antiretroviral therapy (HAART) and the HIV-negative controls. Increases in serum β2-microglobulin were correlated with increases in HIV RNA (P = 0.01). HIV-positive pregnant women showed postpartum increases in plasma HIV RNA, CD4 T cells, and serum β2-microglobulin regardless of the treatment regimen. The rise in CD4 T cells and β2-microglobulin was also observed in HIV-negative pregnant women, suggesting hormonal changes and/or labor-induced cytokines may contribute to immune activation. Immune activation correlated with increased plasma HIV RNA in postpartum women despite treatment, although HAART appeared to blunt the effect. The observed rise in plasma HIV RNA postpartum, which correlated with markers of immune activation, may have implications for enhanced transmission to infants through early breast-feeding and to sexual partners.

Immunity, Inflammation and Infection in Post-partum Breast and Formula Feeders

PROBLEM

Little is known about immunological recovery in post-partum women and if lactational status affects immunocompetence. Many physiological changes occur, such as uterine involution and recovery of non-pregnant immune status. These changes may also affect susceptibility to disease.

METHOD

The study compared immune and inflammatory activation markers (serum cytokines, Epstein Barr viral antibody titer, neopterin, c-reactive protein (CRP), lymphocyte subset percentages, ex vivo cytokine production, lymphocyte proliferation, salivary Immunoglubulin A (sIgA) in exclusively breastfeeding (EB) and exclusively formula feeding (EF) women at 4-6 weeks post-partum, and control (C) women.

RESULTS

EBs had higher ratios of interferon-gamma (IFN-gamma)/interleukin-10 (IL-10) than EFs, and post-partums were higher than Cs. Both IFN-gamma and IL-10 were significantly higher in post-partums compared to controls. Post-partums also had higher proinflammatory cytokines, CRP and neopterin, salivary IgA and fewer infection symptoms. There were also differences in lymphocyte subsets.

CONCLUSIONS

The post-partum period is oriented towards heightened and activated innate and specific immune defenses, with breastfeeding providing a boost in these phenomena.

Phenotypic changes associated with advancing gestation in maternal and fetal baboon lymphocytes

Baboons are very similar to humans in ontogeny, reproductive physiology, and placentation, and thus serve as an excellent nonhuman primate model for use in both normative and perturbation studies of pregnancy that cannot be performed on pregnant women. However, little is known about the changes induced by normal pregnancy in the maternal and fetal baboon in lymphocyte subset composition, and lymphocyte activation and proliferation. We performed multicolor flow cytometry analysis of peripheral venous blood samples obtained from pregnant baboons at mid-gestation (0.5 G), and from matched fetal heart (FH) and umbilical cord (UC) blood at the end of gestation (0.95 G). Compared with their mothers at 0.95 G, fetal lymphocytes had higher percentages of B and CD4+ T cells, and lower numbers of NK and CD8+ T cells. When comparing pregnant baboons at 0.5 and 0.95 G, we also found that pregnancy induces immune stimulation, measured as higher activation without proliferation of CD8+ T and NK cells in the maternal circulation. Our study adds new data to support the notion of pregnancy-induced immune activation and strengthens the value of the baboon as a nonhuman primate model for studies pertinent to human reproductive physiology, pathology, and vaccination.

Urinary neopterin levels in the different stages of pregnancy

BACKGROUND/AIMS

Neopterin is a biochemical marker of activated cell-mediated immune response which increases in pathological conditions associated with cellular immune activation as well as in pregnancy where cellular immune response is predominant. The aim of this study was to determine the urinary neopterin level in each trimester of pregnancy and to determine if it can be used as a marker.

METHODS

104 healthy pregnant women (mean age 22.10 +/- 4.39 years; 36 in the first, 30 in the second and 38 in the third trimester) and 16 non-pregnant healthy women (mean age 20.94 +/- 4.48 year) were included.

RESULTS

The mean urinary neopterin concentration of all pregnant women was higher than that of non-pregnant women (166.4 +/- 31.7 and 103.1 +/- 27.5 micromol/mol creatinine respectively, p < 0.01). The mean urinary neopterin levels in each trimester and non-pregnant women were 139.8 +/- 49.6, 131 +/- 40.2, 227.9 +/- 86.5 and 103.1 +/- 27.5 micromol/mol creatinine, respectively. Urinary neopterin levels were not significantly different between non-pregnant, first and second trimester groups, but were significantly higher in the third trimester than each of these groups (p < 0.05, p < 0.01 and p < 0.01 respectively).

CONCLUSION

Urinary neopterin levels increase significantly in the third trimester probably due to more predominated cellular immunity. The pathologies causing cellular immune activation, especially in the first two trimesters can be predicted with urinary neopterin levels.

J. Complicações perinatais em gestantes infectadas pelo vírus da imunodeficiência humana

OBJETIVOS: analisar as complicações perinatais em gestantes infectadas pelo HIV. MÉTODOS: estudo do tipo coorte, realizado em centro perinatal terciário, no período de 1 de janeiro de 1996 a 31 de março de 2003. Foram selecionadas para o estudo 7698 gestações, cujos critérios de inclusão foram: gestação única e idade gestacional superior a 22 semanas. A infecção pelo HIV foi confirmada pelos testes ELISA e Western Blot. Estudou-se a associação entre a presença da infecção pelo HIV e as seguintes variáveis: ruptura prematura de membranas, parto prematuro, muito baixo peso ao nascimento, infecção puerperal, Apgar baixo no primeiro e quinto minutos, crescimento intra-uterino restrito (CIUR) e pequeno para a idade gestacional (PIG). RESULTADOS: do total de gestantes estudadas, 228 (2,96%) estavam infectadas pelo HIV. Os resultados dos testes estatísticos indicam que a infecção pelo HIV não é fator de risco para a ruptura prematura de membranas (RR = 0,48, p <0,01), parto prematuro (RR = 0,92, p = 0,01), muito baixo peso ao nascimento (RR = 0,69, p = 0,54), infecção puerperal (RR = 0,00, p = 0,31), Apgar menor do que sete no primeiro minuto (RR = 0,81, p = 0,40) e no quinto minuto (RR = 0,36, p = 0.19). Entre as variáveis estudadas, a hipótese de homogeneidade das proporções foi rejeitada para crescimento intra-uterino restrito (RR = 5,27, p <0,01) e pequeno para a idade gestacional (RR = 1,73, p < 0,01). CONCLUSÕES: a ocorrência de complicações maternas e fetais em gestantes infectadas pelo HIV não é diferente da observada em mulheres não infectadas, com exceção CIUR e PIG.

Effect of pregnancy and human immunodeficiency virus infection on intracellular interleukin-2 production patterns

Human immunodeficiency virus type 1 (HIV-1) infection decreases the production of interleukin-2 (IL-2) from CD4+ and CD8+ T cells. Recombinant IL-2 (rIl-2) has been given to HIV-infected individuals to generate significant increases in CD4+ T-cell counts. There are limited data regarding the effects of pregnancy and HIV infection on IL-2 production in humans. To investigate the effects of human pregnancy, HIV infection, and HIV therapy on IL-2 production, we evaluated 61 women. Intracellular IL-2 production by CD4+ T cells from nonpregnant HIV-infected women was significantly lower than in that in uninfected women (45% +/- 8% versus 52% +/- 8%, P = 0.04). In contrast, there was no difference in levels of intracellular IL-2 production between HIV-infected and uninfected pregnant women. These observations suggest that pregnancy may down-regulate IL-2 production regardless of HIV infection status. Future studies should evaluate IL-2 production patterns in larger cohorts of women so that the physiological significance of IL-2 down-regulation in pregnancy can be further evaluated. This information is essential to assess the possible use of IL-2 supplementation therapy as a means of enhancing immune responses among HIV-infected pregnant women.

Severe autoimmune hepatitis first presenting in the early post partum period

BACKGROUND & AIMS

Autoimmune hepatitis (AIH) may run an aggressive clinical course if untreated. The influence of pregnancy on AIH is variable. Both flares in disease activity and remissions, often followed by a post partum flare, are well recognized. In contrast, definite AIH first presenting in the early post partum period has not been reported.

METHODS

We discuss a case series of 5 patients who developed severe AIH within 4 months post partum.

RESULTS

The diagnosis of AIH was definite based on internationally accepted criteria. Liver injury responded to conventional immunosuppressive therapy in all patients. Immune reactivation in the early post partum period may contribute to this entity.

CONCLUSIONS

AIH should be considered in the differential diagnosis of liver dysfunction first presenting in the early post partum period.

Butyrylcholinesterase Activity and Pregnancy-Associated Differences in Immunologically Relevant Peripheral Blood Leukocyte Populations

PROBLEM

Toxic anticholinesterases (AC) are known contributors to negative pregnancy outcome. Impairment of detoxification mechanisms may correlate with occurrence of pregnancy disorders in Kuwait.

METHOD OF STUDY

Butyrylcholinesterase (BuChE), an enzyme which detoxifies AC was evaluated in 18 Kuwaiti women with pregnancy-induced hypertension (PIH), compared with 15 healthy pregnant and eight healthy non-pregnant women. T-lymphocyte subpopulations were measured by flow cytometry, and BuChE activity was measured by spectrophotometry.

RESULTS

Unlike the PIH group, the normal pregnancy group exhibited a significant increase in BuChE activity compared with non-pregnant control subjects (P = 0.04). Within the PIH cohort, inverse correlations were observed between BuChE activity and percentage of CD4+ CD25+ cells (P = 0.001), and CD8+ CD25+ cells (P = 0.007).

CONCLUSIONS

Elevated BuChE activity in normal pregnancy may correlate with better ability to clear pregnancy-threatening toxins, while lesser ability to do this in PIH women may be a contributor to disease. The fact that PIH subjects with large subpopulations of activated T cells also exhibited low BuChE activity further suggests a correlation between susceptibility to pregnancy loss and decreased activity of the enzyme.

Longitudinal study of tryptophan degradation during and after pregnancy

In mice, activation of indoleamine-2,3-dioxygenase (IDO), an enzyme converting tryptophan to N-formyl-kynurenine, was found to be necessary requirement to achieve immunotolerance against the fetus and thus uncomplicated pregnancy. In plasma from 20 healthy pregnant women with singleton pregnancies we consecutively analyzed kynurenine and tryptophan concentrations during pregnancy (1 specimen at each trimester of gestation) and postpartum (week 6). None of the women had any signs of infection at the time of plasma sampling, but the study population was otherwise unselected. The kynurenine to tryptophan ratio (kyn/trp) was calculated as an estimate of IDO activity, and data were compared to concentrations of neopterin and 55kD soluble tumor necrosis factor receptor (sTNF-R55), two indicators of immune activation, and to alanineaminotransferase (ALT) levels. Increasing kynurenine and decreasing tryptophan concentrations were found during pregnancy, data suggesting significant degradation of tryptophan. In parallel, increasing concentrations of immune activation markers neopterin and sTNF-R55 were observed, correlating significantly to kyn/trp. The data point to an involvement of cytokine-induced IDO activation in the degradation of tryptophan observed during pregnancy. After pregnancy, sTNF-R55 and also neopterin concentrations declined, whereas tryptophan concentrations increased, indicating that immune activation and activation-induced tryptophan degradation returned to baseline. By contrast, still increased kynurenine concentrations and also increased kyn/trp point to continuing catabolism of tryptophan. Postpartum elevation of liver enzyme ALT may suggest that increased activity of hepatic tryptophan pyrrolase could be involved in increased conversion of tryptophan despite low degree of immune activation. We conclude that IDO is activated in pregnancy and that the decrease of tryptophan might be related to immune activation phenomena. Sustained increase of kynurenine postpartum seems independent from immune activation process.

Soluble CD4 concentrations predict relapse of post-partum thyroiditis

Post-partum thyroiditis (PPT) is a common autoimmune thyroid disorder which results in significant morbidity at a critical time of a woman's life. The presence of anti-thyroglobulin (anti-TG) and, more so, anti-thryroperoxidase (anti-TPO) antibodies in the first trimester of pregnancy has been reported to forecast subsequent PPT. Despite their predictive value, these tests lack in specificity. We have sought to find an alternative that is more specific and, ideally, which could be tested immediately proximate to the event. We have taken advantage of the high recurrence rate of PPT in subsequent pregnancies to perform a prospective study of serum soluble CD4 (sCD4) and CD8 (sCD8) levels in 22 pregnant women who had at least one previous episode of PPT. This group was matched with 21 pregnant women of comparable age with no evidence of thyroid disease. Both groups of women were sampled in each of the three trimesters of pregnancy, 1 month, 3 months and 6 months post-partum for sCD4, sCD8, thyroid function parameters and antibodies. Twelve of the 22 women with previous PPT had recurrent disease; they were more likely to be cigarette smokers and to have a family history of autoimmune disorders (p<0.05, for both) than those who did not. Half of these women had high anti-TG or anti-TPO each in the first trimester compared to none among those without recurrent PPT and 2/21 controls. Serum sCD8 levels showed no changes over the observation points among the two PPT patient subsets and were comparable to those of the controls. By contrast, serum sCD4 concentrations showed divergent changes in the group with recurrent PPT in the course of pregnancy and postpartum period compared to those without disease recurrence and controls: sCD4 failed to show the physiological fall in the third trimester of pregnancy [19.0+/-1.7 (+/-SD) U/ml vs 15.6+/-2.3 U/ml in controls, NS]. This trend was continued into the first month post-partum when sCD4 levels were clearly higher than in controls (22.1+/-2.6 U/ml compared to 17.9+/-1.9 U/ml in controls, p<0.001) and well before the episode of PPT. An sCD4 serum level outside the 95% reference range at 1 month post-partum (9/12 in recurrent PPT, 1/21 in controls) yields a relative risk of 6.9 (chi2=14.67, p<0.001) compared to 3.3 for first trimester thyroid antibody positivity (p=0.029). In summary, we describe a reliable test for forecasting PPT that can be obtained immediately proximate to the possible event. If our findings are verified in larger studies, the measurement of serum sCD4 concentration drawn in the first month post-partum may prove an ideal test for population screening for impending PPT.

Neopterin measurement in clinical diagnosis

Neopterin is a marker associated with cell-mediated immunity. It is produced in monocytes/macrophages primarily upon stimulation with interferon-gamma. Due to its chemical structure, neopterin belongs to the class of pteridines. It is excreted in an unchanged form via the kidneys. Serum levels above 10 nmol/L are regarded as elevated. The levels of neopterin in body fluids are elevated in infections, autoimmune diseases, malignancies, allograft rejection, cardiac and renal failure, coronary artery disease and myocardial infarction. Neopterin measurements not only provide an insight into the present state of cell-mediated immune response but also allow monitoring and prognosis of disease progression.

Thyroid disease in relation to pregnancy: a decade of change

Inspection of the references cited in this review indicates that much work has occurred in the area of thyroid and pregnancy during the last decade. Significant advances in our understanding of the immunology of pregnancy and the effect of thyroid disease on this process have taken place. The role of hCG in the physiology of pregnancy and its relevance to thyroid function has been an emerging theme. There is still no clear explanation for the association between thyroid antibodies and infertility or miscarriage. During the last decade a general concensus has developed in relation to the management of hyperthyroidism in pregnancy although there are still variations in antithyroid drug use at this time. The aetiological classification of congenital hyper- and hypothyroidism utilizing new technologies has opened up a new perspective on these disorders. Attention has been drawn to the importance of treating maternal hypothyroidism with adequate thyroid replacement therapy and to the possibility of impaired child neuropsychological development consequent on low maternal thyroid hormone concentration in early gestation in non iodine deficient areas. Significant advances have been made during the last decade in the description of the clinical features and in our understanding of the pathogenesis of postpartum thyroid disease. The importance of long-term follow up of selected patient groups has also been emphasized.

Uterine leukocytes: key players in pregnancy

In species with hemochorial placentation, which includes humans, mice and rats, antigen-specific T and B lymphocytes which are responsible for acquired immunity are virtually absent from the maternal-fetal interface. In contrast, non-antigen specific natural killer cells and macrophages which provide innate immunity are abundant and highly specialized. Autocrine/paracrine factors such as steroid and polypeptide hormones, prostaglandins and anti-inflammatory cytokines that are present in the uterine environment during pregnancy re-program their secretory profiles. Recent studies using transgenic mice and other approaches indicate that these environmentally modified leukocytes have major pregnancy-associated functions that include facilitation of implantation, modulation of the maternal uterine vasculature, supply of growth factors to the placenta, promotion of trophoblast differentiation and facilitation of parturition.