Umbilical Cord Maternal Microchimerism in Normal and Preeclampsia Pregnancies

Bidirectional exchange of cells between mother and fetus establishes microchimerism (Mc). Mc can persist for decades and is associated with later-life health and disease. Greater fetal Mc is detected in the maternal compartment in preeclampsia (PE), but whether maternal Mc (MMC) in umbilical cord blood (CB) is altered in PE is unknown. We evaluated MMc in CB from normal and PE pregnancies. DNA from CB mononuclear cells following placental delivery (n = 36 PE, n = 37 controls) and maternal blood was extracted and genotyped. MMc, quantified by qPCR assays targeting maternal-specific nonshared polymorphisms in CB, was compared using logistic and negative binomial regression models. Clinically and statistically relevant confounders were included, and included the total number of cell equivalents tested, gravidity, mode of delivery, birthweight, and fetal sex. PE participants delivered at earlier gestational ages, with higher Cesarean rates, and lower infant birthweights. CB MMc detection was similar between PE and controls (52.8% vs. 51.3%, respectively, p = 0.90) and unchanged after adjustment for confounders. MMc concentration was not different between groups (mean 73.7 gEq/105 gEq in PE vs. mean 22.8 gEq/105 in controls, p = 0.56), including after controlling for confounders (p = 0.64). There was no difference in CB MMc detection or concentration between PE and normal pregnancies, despite previously noted greater fetal Mc in the maternal compartment. This suggests possible differential transfer of cells at the maternal fetal interface in PE. Phenotypic evaluation of Mc cells may uncover underlying mechanisms for differential cellular exchange between mother and fetus in PE.

Fetal microchimerism by mode of delivery: a prospective cohort study

OBJECTIVE

To compare fetal microchimerism (FMc) in pregnancies with uncomplicated vaginal delivery (VD) versus caesarean delivery (CD).

DESIGN

Prospective cohort study.

SETTING

University of Washington and Fred Hutchinson Cancer Research Center, USA.

POPULATION

Women delivering singleton pregnancies without pertinent antenatal complications with uncomplicated deliveries (n = 36).

METHODS

We collected maternal predelivery, postdelivery and umbilical cord blood for each mother-baby pair. Following maternal and fetal genotyping, FMc was measured with quantitative polymerase chain reaction assays targeting fetus-specific polymorphisms. Quantification of FMc is expressed as genome equivalents (gEq) of fetal DNA/100 000 total gEq tested. FMc detection was evaluated by logistic regression while controlling for total number of cell equivalents tested and clinically relevant covariates. FMc concentrations were compared using negative binomial regression while controlling for the same covariates and predelivery FMc positivity.

MAIN OUTCOME MEASURE

Detection and concentration of FMc by mode of delivery.

RESULTS

Twenty-four mother-baby pairs had a VD and 12 had a CD. Postdelivery FMc detection was higher following CD than after VD (58.3% versus 16.7%, P = 0.02). After controlling for covariates, the likelihood of postdelivery FMc detection was almost nine-fold higher after CD than VD (odds ratio 8.8, 95% CI 1.6-47.6; P = 0.01). With respect to postdelivery FMc concentration, the detection rate ratio for CD versus VD in the adjusted negative binomial regression model was 14.7 (95% CI 3.2-66.8; P = 0.001).

CONCLUSION

Postdelivery peripheral FMc detection and concentration are significantly higher after CD than after VD. As FMc is associated with long-term maternal health, our findings suggest that the mode of delivery may impact this risk.

TWEETABLE ABSTRACT

Greater fetal microchimerism found in maternal blood following caesarean delivery compared with vaginal delivery.

Effect of oral nutritional supplementation on wound healing in diabetic foot ulcers: a prospective randomized controlled trial

AIMS

Among people with diabetes, 10-25% will experience a foot ulcer. Research has shown that supplementation with arginine, glutamine and β-hydroxy-β-methylbutyrate may improve wound repair. This study tested whether such supplementation would improve healing of foot ulcers in persons with diabetes.

METHODS

Along with standard of care, 270 subjects received, in a double-blinded fashion, (twice per day) either arginine, glutamine and β-hydroxy-β-methylbutyrate or a control drink for 16 weeks. The proportion of subjects with total wound closure and time to complete healing was assessed. In a post-hoc analysis, the interaction of serum albumin or limb perfusion, as measured by ankle-brachial index, and supplementation on healing was investigated.

RESULTS

Overall, there were no group differences in wound closure or time to wound healing at week 16. However, in subjects with an albumin level of ≤ 40 g/l and/or an ankle-brachial index of < 1.0, a significantly greater proportion of subjects in the arginine, glutamine and β-hydroxy-β-methylbutyrate group healed at week 16 compared with control subjects (P = 0.03 and 0.008, respectively). Those with low albumin or decreased limb perfusion in the supplementation group were 1.70 (95% CI 1.04-2.79) and 1.66 (95% CI 1.15-2.38) times more likely to heal.

CONCLUSIONS

While no differences in healing were identified with supplementation in non-ischaemic patients or those with normal albumin, addition of arginine, glutamine and β-hydroxy-β-methylbutyrate as an adjunct to standard of care may improve healing of diabetic foot ulcers in patients with risk of poor limb perfusion and/or low albumin levels. Further investigation involving arginine, glutamine and β-hydroxy-β-methylbutyrate in these high-risk subgroups might prove clinically valuable.

Prospective assessment of fetal-maternal cell transfer in miscarriage and pregnancy termination

BACKGROUND

Fetal cells (microchimerism) are acquired by women during pregnancy. Fetal microchimerism persists decades later and includes cells with pluripotent capacity. Persistent microchimerism has the capacity for both beneficial and detrimental maternal health consequences. Both miscarriage and termination of pregnancy can result in fetal microchimerism. We sought to determine whether cellular fetal microchimerism is acquired during management of pregnancy loss and further explored factors that could influence fetal cell transfer, including viability of fetal tissue, surgical versus medical management and gestational age.

METHODS

Pregnant women (n= 150 samples from 75 women) with singleton pregnancies undergoing a TOP (n= 63) or treatment for embryonic or fetal demise (miscarriage, n= 12) were enrolled. Mononuclear cells were isolated from blood samples drawn before, and 30 min after, treatment. Fetal cellular microchimerism concentrations were determined using quantitative PCR for a Y chromosome-specific sequence, expressed as genome equivalents of fetal DNA per 100 000 maternal cell equivalents (gEq/10(5)). Detection rate ratios were determined according to clinical characteristics.

RESULTS

Cellular fetal microchimerism was found more often in post- compared with pretreatment samples, 24 versus 5% (P= 0.004) and at higher concentrations, 0-36 versus 0-0.7 gEq/10(5) (P< 0.001). Likelihood of microchimerism was higher in surgical than medical management, detection rate ratio 24.7 (P= 0.02). The detection rate ratio for TOP versus miscarriage was 16.7 for known male fetuses (P= 0.02). Microchimerism did not vary with gestational age.

CONCLUSIONS

Significant fetal cell transfer occurs during miscarriage and TOP. Exploratory analyses support relationships between obstetric clinical factors and acquisition of fetal cellular microchimerism; however, our limited sample size precludes definitive analysis of these relationships, and confirmation is needed. In addition, the long-term persistence and potential consequences of fetal microchimerism on maternal health merit further investigation.

Dynamic changes in fetal microchimerism in maternal peripheral blood mononuclear cells, CD4+ and CD8+ cells in normal pregnancy

OBJECTIVE

Cell trafficking during pregnancy results in persistence of small populations of fetal cells in the mother, known as fetal microchimerism (FMc). Changes in cell-free fetal DNA during gestation have been well described, however, less is known about dynamic changes in fetal immune cells in maternal blood. We have investigated FMc in maternal peripheral blood mononuclear cells (PBMC) longitudinally across gestation.

STUDY DESIGN

Thirty-five women with normal pregnancies were studied. FMc was identified in PBMC, CD4+ and CD8+ subsets employing quantitative PCR assays targeting fetal-specific genetic polymorphisms. FMc quantities were reported as fetal genome equivalents (gEq) per 1,000,000 gEq mother's cells. Poisson regression modeled the rate of FMc detection.

MAIN OUTCOME MEASURE

FMc in PBMC.

RESULTS

The probability of detecting one fetal cell equivalent increased 6.2-fold each trimester [Incidence Rate Ratio (IRR) 95% CI: 1.73, 21.91; p = 0.005]. Although FMc in PBMC was not detected for the majority of time points, 7 of 35 women had detectable FMc during pregnancy at one or more time points, with the majority of positive samples being from the third trimester. There was a suggestion of greater HLA-sharing in families where women had FMc in PBMC. FMc was detected in 9% of CD4+ (2/23) and 18% of CD8+ (3/25) subsets.

CONCLUSIONS

FMc in PBMC increased as gestation progressed and was found within CD4+ and CD8+ subsets in some women in the latter half of gestation. A number of factors could influence cellular FMc levels including sub-clinical fetal-maternal interface changes and events related to parturition. Whether FMc during pregnancy predicts persistent FMc and/or correlates with fetal-maternal HLA relationships also merits further study.

The STAT4 gene influences the genetic predisposition to systemic sclerosis phenotype

The aim of this study was to investigate the possible role of STAT4 gene in the genetic predisposition to systemic sclerosis (SSc) susceptibility or clinical phenotype. A total of 1317 SSc patients [896 with limited cutaneous SSc (lcSSc) and 421 with diffuse cutaneous SSc (dcSSc)] and 3113 healthy controls, from an initial case-control set of Spanish Caucasian ancestry and five independent cohorts of European ancestry (The Netherlands, Germany, Sweden, Italy and USA), were included in the study. The rs7574865 polymorphism was selected as STAT4 genetic marker. We observed that the rs7574865 T allele was significantly associated with susceptibility to lcSSc in the Spanish population [P = 1.9 x 10(-5) odds ratio (OR) 1.61 95% confidence intervals (CI) 1.29-1.99], but not with dcSSc (P = 0.41 OR 0.84 95% CI 0.59-1.21). Additionally, a dosage effect was observed showing individuals with rs7574865 TT genotype higher risk for lcSSc (OR 3.34, P = 1.02 x 10(-7) 95% CI 2.11-5.31). The association of the rs7574865 T allele with lcSSc was confirmed in all the replication cohorts with different effect sizes (OR ranging between 1.15 and 1.86), as well as the lack of association of STAT4 with dcSSc. A meta-analysis to test the overall effect of the rs7574865 polymorphism showed a strong risk effect of the T allele for lcSSc susceptibility (pooled OR 1.54 95% CI 1.36-1.74; P < 0.0001). Our data show a strong and reproducible association of the STAT4 gene with the genetic predisposition to lcSSc suggesting that this gene seems to be one of the genetic markers influencing SSc phenotype.

A large multicentre analysis of CTGF -945 promoter polymorphism does not confirm association with systemic sclerosis susceptibility or phenotype

OBJECTIVE

To conduct a replication study to investigate whether the -945 CTGF genetic variant is associated with systemic sclerosis (SSc) susceptibility or specific SSc phenotype.

METHODS

The study population comprised 1180 patients with SSc and 1784 healthy controls from seven independent case-control sets of European ancestry (Spanish, French, Dutch, German, British, Swedish and North American). The -945 CTGF genetic variant was genotyped using a Taqman 5' allelic discrimination assay.

RESULTS

An independent association study showed in all the case-control cohorts no association of the CTGF -945 polymorphism with SSc susceptibility. These findings were confirmed by a meta-analysis giving a pooled OR = 1.12 (95% CI 0.99 to 1.25), p = 0.06. Investigation of the possible contribution of the -945 CTGF genetic variant to SSc phenotype showed that stratification according to SSc subtypes (limited or diffuse), selective autoantibodies (anti-topoisomerase I or anticentromere) or pulmonary involvement reached no statistically significant skewing.

CONCLUSION

The results do not confirm previous findings and suggest that the CTGF -945 promoter polymorphism does not play a major role in SSc susceptibility or clinical phenotype.

Non-inherited maternal human leukocyte antigen alleles in susceptibility to familial rheumatoid arthritis

OBJECTIVES

Some patients with rheumatoid arthritis (RA) lack RA-associated human leukocyte antigen (HLA) alleles. Prior studies investigated non-inherited maternal HLA alleles (NIMA) in RA risk with conflicting results.

METHODS

We examined NIMA in a large cohort of families from the North American Rheumatoid Arthritis Consortium (NARAC).

RESULTS

Among 620 patients with 1 or both parents having a HLA genotype, patients with RA informative for analysis included 176 without HLA-DRB1*04 and 86 without the HLA shared epitope (SE). The frequency of NIMA encoding HLA-DR4 or the SE was compared to the non-inherited paternal allele (NIPA). DR4-encoding NIMA vs NIPA revealed no significant difference (27% vs 20%). However, parity is known to modulate RA risk and analyses stratified by sex and age of onset showed significant variation among women. Interestingly, among women with onset <45 years DR4-encoding NIMA was increased compared to NIPA; among women > or =45 years at onset the reverse was observed (31% vs 16% compared to 10% vs 60%, p = 0.008). DR4 encoding NIMA vs NIPA did not differ in men. The SE did not differ in men or women.

CONCLUSIONS

Risk of RA was associated with HLA-DR4 encoding NIMA in younger-onset women but not in older-onset women or men. These observations could help explain conflicting prior results of NIMA in RA.

Resequencing of the human major histocompatibility complex in patients with rheumatoid arthritis and healthy controls in Alaska Natives of Southeast Alaska

High prevalence and severity of rheumatoid arthritis (RA) with an early age of onset have previously been described in Alaska Native and American Indian (AN/AI) populations. The contribution of HLA-DRB1 alleles encoding a similar amino acid sequence, referred to as the shared epitope (SE), to RA risk is well recognized in multiple populations worldwide. DRB1*1402 allele is the major SE-encoding allele in AN/AI populations. However, DRB1*1402 is highly prevalent in healthy Alaska Natives of Southeast Alaska (AN), with no significant difference from RA patients, indicating this allele alone is not informative for defining genetic risk and non-human leukocyte antigen (non-HLA) genes are likely important in AN. We sought to deep resequence the human major histocompatibility complex (MHC) to characterize the single-nucleotide polymorphism (SNP) haplotypes within this region in RA cases and controls in AN. Approximately 99 kb of the MHC was resequenced with 95 amplicons throughout this region. Thirty-four cases and 74 controls were examined. A total of 696 SNPs were discovered from 85 of the selected 95 amplicons. Disease association signals were detected for nine of the 95 amplicons analyzed. Increased risk of RA was associated with five amplicons in the class I, class II or class III region and resistance to disease with four amplicons in the class I region. Our results indicate that non-HLA MHC genes and/or unknown exogenous factors likely modulate risk of RA in the AN population.

A defined medium supports changes consistent with capacitation in stallion sperm, as evidenced by increases in protein tyrosine phosphorylation and high rates of acrosomal exocytosis

Efficient in vitro capacitation of stallion sperm has not yet been achieved, as suggested by low sperm penetration rates reported in in vitro fertilization (IVF) studies. Our objectives were to evaluate defined incubation conditions that would support changes consistent with capacitation in stallion sperm. Protein tyrosine phosphorylation events and the ability of sperm to undergo acrosomal exocytosis under various incubation conditions were used as end points for capacitation. Sperm incubated 4-6h in modified Whitten's (MW) with the addition of 25 mM NaHCO3 and 7 mg/mL BSA (capacitating medium) yielded high rates of protein tyrosine phosphorylation. Either HCO3(-) or BSA was required to support these changes, with the combination of both providing the most intense results. When a membrane-permeable form of cAMP and a phosphodiesterase inhibitor (IBMX) were added to MW in the absence of HCO3(-) and BSA, the tyrosine phosphorylation results obtained in our capacitating conditions could not be replicated, suggesting either effects apart from cAMP were responsible for tyrosine phosphorylation, or that stallion sperm might respond differently to these reagents as compared to sperm from other mammals. Sperm incubation in capacitating conditions was also associated with high percentages (P<or=0.001) of acrosomal exocytosis upon exposure to progesterone (44.6%) or calcium ionophore (51.6%), as compared to sperm incubated in medium devoid of BSA and NaHCO3. Our results were novel in that we report protein tyrosine phosphorylation in stallion sperm incubated in defined conditions, coupled with significant percentages of acrosome reacted sperm. The continuation of these studies might help to elucidate the conditions and pathways supporting sperm capacitation in the horse.

Diet of the tiger quoll (Dasyurus maculatus) in south-eastern Australia

Analysis of 338 tiger quoll scats from tableland moist forest in south-eastern New South Wales found that the greater glider was the major prey species occurring in 54.1% of scats and contributing an estimated 51.01% of the biomass consumed by tiger quolls. Medium-sized (0.5–5 kg) mammals were the most important prey group by occurrence (53.9%), frequency (66.0%) and estimated biomass contribution to diet (62.93%). Other medium-sized prey taken by tiger quolls included: long-nosed bandicoot, rabbit, brushtail possum and ringtail possum. Macropods and wombats were also present in the scats and had been presumably taken as carrion. There was no significant difference in the diets of male and female tiger quolls. Tiger quolls were recorded hunting greater gliders in their tree hollows during the day, hunting rabbits in their burrows both during the day and at night and were observed eating road-killed macropods and wombats around dawn and dusk.

A comparison of three hair-tube types for the detection of the spotted-tailed quoll Dasyurus maculatus in south-eastern New South Wales

The effectiveness of three different hair-tube designs at detecting the rare and cryptic forest-dependent spotted-tailed quoll Dasyurus maculatus was investigated in two trials conducted across 60 sites in an area known to be inhabited by the species. During the two trials D. maculatus was detected at a total of 14 sites. While the three hair-tube types trialed all successfully detected the species, the Faunatech hair-funnel, a hair-tube manufactured from plastic moulded into a half funnel, detected the species from the greatest number of sites and accounted for the greatest proportion of records. This hair-tube type was found to provide the most effective tool for determining the presence of D. maculatus in the typically wet environment of the study area.

Human leukocyte antigen class II alleles in Caucasian women with primary biliary cirrhosis

In the current study, we investigated human leukocyte antigen (HLA) class II alleles in Caucasian women with primary biliary cirrhosis (PBC), a disease that preferentially affects women. Alleles of DRB1, DQA1, and DQB1 were determined by DNA-based HLA typing for women with PBC (n = 72) and healthy women (n = 381). All study subjects were Caucasian. HLA DRB1*08 was significantly increased in women with PBC compared to healthy women. The increase was primarily due to the DRB1*0801 allele, also the most common DRB1*08 allele among controls. DQB1*04 and DQA1*0401 were significantly increased. DRB1*1501, DQA1*0102, and DQB1*0602 were associated with decreased risk. Analyses conducted comparing parous women with PBC to parous healthy women (n = 68 and n = 282, respectively) yielded similar significant results. Although the DRB1*08-DQA1*0401-DQB1*04 haplotype was significantly associated with PBC, consistent with other studies, this haplotype nevertheless represented only 19% (14/72) of all PBC patients and can account for only a minority of the risk of PBC.

Characterization of certified Angus beef steaks from the round, loin, and chuck

Beef carcasses (n = 150) of A-maturity were selected randomly to determine baseline shear force and sensory panel ratings, assess variation in tenderness, and evaluate mean value differences between Certified Angus Beef (CAB), commodity Choice, and Select steaks. Three steaks were removed from the triceps brachii (TB), longissimus lumborum (LL), gluteus medius (GM), semimembranosus (SM), biceps femoris (BF), and quadriceps femoris complex (QF), and assigned to Warner-Bratzler shear (WBSF) and sensory panel analyses. As anticipated, marbling score and measured percentage of i.m. fat were greatest (P < 0.05) for CAB, intermediate (P < 0.05) for Choice, and least (P < 0.05) for Select carcasses. A muscle x quality level interaction (P < 0.05) was observed for WBSF values and sensory panel tenderness ratings. The TB, LL, GM, and BF steaks from CAB carcasses had lower (P < 0.05) WBSF than Select steaks from the same muscles. Even though WBSF values did not differ (P > 0.05) between CAB and Choice QF and TB steaks, the LL and GM steaks from CAB carcasses were more tender (P < 0.05) than Choice-grade LL and GM steaks. The TB from Select carcasses had higher (P < 0.05) WBSF values than TB steaks from CAB or Choice carcasses, but sensory panel ratings indicated that quality level showed little consistency among the GM, SM, BF, and QF. Trained sensory panelists rated CAB LL steaks more tender (P < 0.05) than LL steaks from Choice and Select carcasses, and Choice LL steaks were evaluated as more (P < 0.05) tender than those from Select carcasses. These results demonstrate that the influence of marbling on tenderness was more evident in muscles of middle meats than in end cuts, particularly in muscles of the round.

HLA allelic variants encoding DR11 in diffuse and limited systemic sclerosis in Caucasian women

OBJECTIVE

We investigated HLA class II alleles in women with systemic sclerosis (SSc), a rare disease that preferentially affects women.

METHODS

Specific alleles of DRB1, DQA1 and DQB1 were determined by DNA-based HLA typing for women with SSc (n = 102) and healthy women (n = 533). All study subjects were Caucasian. DRB1, DQA1 and DQB1 allele frequencies of women with SSc were compared with those of healthy women.

RESULTS

Among women with SSc, 29.4% (30/102) and among healthy women 10.7% (57/533) had DRB1*11. Allele frequencies were compared for women with SSc and healthy women (each woman has two alleles). The allele frequency of DRB1*11 was 15.7% (32/204 alleles) in SSc women and 5.8% (62/1066 alleles) in healthy women (P = 0.000002). The increase of DRB1*11 was found both in diffuse (P = 0.0001) and limited SSc (P = 0.002) (allele frequencies 15.0 and 17.2%, respectively). Among women with diffuse SSc, there was a disproportionate increase of the DRB1*1104 allele (P = 0.0004) with no increase of DRB1*1101 (P = 1.00). In contrast, in limited SSc the strongest association was with DRB1*1101 (P = 0.008), with a less significant increase of DRB1*1104 (P = 0.04).

CONCLUSIONS

An increase of DRB1*11 in SSc is consistent with other reports. Although present in both diffuse and limited SSc disease subsets, the increase was predominantly due to over-representation of DRB1*1104 in women with diffuse SSc. Women with limited SSc had a preponderance of DRB1*1101, the most common allele in healthy women. DRB1*1104 and DRB1*1101 differ by a single amino acid at position 86, where the former has valine and the latter glycine.

Male microchimerism in women with systemic sclerosis and healthy women who have never given birth to a son

BACKGROUND

Male DNA or cells are often used to measure microchimerism in a woman. In studies of autoimmune diseases male microchimerism is most often attributed to the previous birth of a son.

OBJECTIVE

To determine the frequency of male microchimerism in healthy women or women with systemic sclerosis who had never given birth to a son.

METHODS

Real time quantitative polymerase chain reaction targeting the Y chromosome specific sequence DYS14 was employed to test DNA extracted from peripheral blood mononuclear cells of 26 women with systemic sclerosis and 23 healthy women who had never given birth to a son.

RESULTS

are expressed as the genome equivalent number of male cells per million host cells (gEq/mil).Results: Male DNA was found in 15% of women with systemic sclerosis (range 0 to 23.7 gEq/mil) and in 13% of healthy women (range 0 to 5.1 gEq/mil). Although two women with male DNA had an induced abortion, most had no history of spontaneous or induced abortion (either systemic sclerosis or healthy).

CONCLUSIONS

Microchimerism with male DNA can be found in the circulation of women who have never given birth to a son. Thus sources other than a male birth must be considered when male DNA is used to measure microchimerism. Although other studies are needed, there was no apparent difference in women with systemic sclerosis and healthy women. Possible sources of male DNA include unrecognised male pregnancy or unrecognised male twin, an older male sibling with transfer through the maternal circulation, or sexual intercourse alone.

Pregnancy in patients with rheumatic disease: anti-inflammatory cytokines increase in pregnancy and decrease post partum

OBJECTIVE

To investigate changes in the levels of circulating cytokines with a focus on the Th1/Th2 balance during and after pregnancy in patients with rheumatoid arthritis (RA), juvenile idiopathic arthritis (JIA), and ankylosing spondylitis (AS).

METHODS

Plasma and serum samples of 34 pregnant patients, 19 with RA, 6 with JIA, and 9 with AS, and of 30 healthy pregnant women, 20 non-pregnant patients, and 10 non-pregnant healthy women were analysed for levels of interferon gamma (IFNgamma), interleukin (IL) 1beta, IL10, IL1 receptor antagonist (IL1Ra), soluble tumour necrosis factor receptor (sTNFR), and soluble CD30 (sCD30) by ELISA. Clinical assessment and blood sampling in pregnant women was done once in each trimester and 6, 12, and 24 weeks post partum. Disease activity in the patients was evaluated by validated clinical instruments and correlated with circulating levels of cytokines.

RESULTS

Low levels of IL10 were found sporadically, whereas IFNgamma and IL1beta were below detection level in the samples tested. Significantly higher concentrations of sTNFR and IL1Ra were measured in pregnant than in non-pregnant subjects. An increase of IL1Ra from the second to the third trimester correlated with improvement of disease activity in patients with RA and AS. Compared with non-pregnant patients and the other pregnant women, patients with RA showed markedly raised levels of sCD30 during pregnancy.

CONCLUSIONS

IFNgamma and IL10, markers of a Th1 and Th2 response, respectively, were either low or undetectable in the cohorts analysed. The increase of cytokine inhibitors IL1Ra and sTNFR was related to pregnancy and was independent of an underlying disease. These anti-inflammatory mediators seem to affect disease activity.

Maternal and sibling microchimerism in twins and triplets discordant for neonatal lupus syndrome-congenital heart block

OBJECTIVE

Neonatal lupus syndrome-congenital heart block (NLS-CHB) is an acquired autoimmune disease in which maternal autoantibodies are necessary but not sufficient for disease. Maternal myocardial cells have been found in the hearts of patients with NLS-CHB, suggesting that maternal microchimerism may also play a role. In this study we asked whether levels of microchimerism in the blood are associated with NLS-CHB in discordant twins and triplets.

METHODS

Human leucocyte antigen (HLA)-specific and Y-chromosome-specific real-time quantitative polymerase chain reaction (PCR) was used to quantitatively assay maternal and sibling microchimerism in peripheral blood. Because of HLA allele sharing in families, it was not always possible to distinguish between multiple sources of microchimerism.

RESULTS

In one family, maternal and/or sibling microchimerism was detected in two triplets who had CHB, but not in the triplet with transient hepatitis. Levels ranged from 4 to 948 genome-equivalents of foreign deoxyribonucleic acid per million host genome-equivalents (gEq/million). Over the first year levels of sibling microchimerism decreased in the triplet with complete CHB and increased in the triplet who progressed from first- to second-degree CHB. In a second family, maternal and/or sibling microchimerism was detected in the healthy twin (1223 gEq/million) but not in the twin with CHB.

CONCLUSIONS

Maternal and/or sibling microchimerism was detectable in the blood of infant twins and triplets discordant for NLS. Microchimerism in the blood was not specific for NLS-CHB, although in one family levels correlated with disease. Thus, microchimerism in the blood and/or tissues may be involved in the pathogenesis or progression of NLS-CHB, but additional factors must also contribute. Further investigation is warranted.

Ultrasonic-enhanced gentamicin transport through colony biofilms of Pseudomonas aeruginosa and Escherichia coli

The hypothesis that ultrasound increases antibiotic transport through biofilms of Escherichia coli and Pseudomonas aeruginosa was investigated using colony biofilms. Biofilms grown on membrane filters were transferred to nutrient agar containing 50 microg/ml gentamicin. A smaller filter was placed on top of the biofilm and a blank concentration disk was situated atop the filter. Diffusion of antibiotic through the biofilms was allowed for 15, 30, or 45 min at 37 degrees C. Some of these biofilms were exposed to 70-kHz ultrasound and others were not. Each concentration disk was then placed on a nutrient agar plate spread with a lawn of E. coli. The resulting zone of inhibition was used to calculate the amount of gentamicin that was transported through the biofilm into the disk. The E. coli and P. aeruginosa biofilms grown for 13 and 24 h were exposed to two different ultrasonic power densities. Ultrasonication significantly increased the transport of gentamicin through the biofilm. Insonation of biofilms of E. coli for 45 min more than doubled the amount of gentamicin compared to their noninsonated counterparts. For P. aeruginosa biofilms, no detectable gentamicin penetrated the biofilm within 45 min without ultrasound; however, when insonated (1.5 W/cm2) for 45 min, the disks collected more than 0.45 microg antibiotic. Ultrasonication significantly increased transport of gentamicin across biofilms that normally blocked or slowed gentamicin transport when not exposed to ultrasound. This enhanced transport may be partially responsible for the increased killing of biofilm bacteria exposed to combinations of antibiotic and ultrasound.

Ultrasonically enhanced vancomycin activity against Staphylococcus epidermidis biofilms in vivo

Infection of implanted medical devices by Gram-positive organisms such as Staphylococcus ssp. is a serious concern in the biomaterial community. In this research the application of low frequency ultrasound to enhance the activity of vancomycin against implanted Staphylococcus epidermidis biofilms was examined. Polyethylene disks covered with a biofilm of S. epidermidis were implanted subcutaneously in rabbits on both sides of their spine. The rabbits received systemic vancomycin for the duration of the experiment. Following 24 h of recovery, one disk was insonated for 24 or 48 h while the other was a control. Disks were removed and viable bacteria counted. At 24 h of insonation, there was no difference in viable counts between control and insonated biofilms, while at 48 h of insonation there were statistically fewer viable bacteria in the insonated biofilm. The S. epidermidis biofilms responded favorably to combinations of ultrasound and vancomycin, but longer treatment times are required for this Gram-positive organism than was observed previously for a Gram-negative species.

Gamma/delta T cells in placenta and skin: their different functions may support the paradigm of microchimerism in systemic sclerosis

Increased amounts of foetal cells persisting after pregnancy could be involved in the pathogenesis of systemic sclerosis (SSc) and other autoimmune diseases. Evidence suggests a specific role for a subset of T lymphocytes showing the gamma/delta T cell receptor (TCR) at the foetal/maternal interface. gamma/delta T cells significantly increase in the early pregnancy decidua and recognize trophoblast antigens, probably a highly evolutionarily conserved molecule such as Hsp60 or Hsp60-derived peptides, and are likely to suppress the maternal anti-foetal immune response via TGFbeta production, thus contributing to pregnancy maintenance. The similarity between the presence of host gamma/delta T cells in pregnancy decidua and in SSc skin suggests that the functional activities of these cells can be differentially modulated by several mechanisms including the nature of the antigen and the involved organs. To support pregnancy, the decidual microenvironment might induce a Th2 activity of host Vdelta1 + T cells. On the contrary, either the presence of foetal cells in the skin of SSc patients or an as yet unidentified stimulus (i.e. infections), may trigger Vdelta1 + T cells toward the Th1 phenotype with the subsequent activation of cytotoxicity and modulation of the cytotoxic alpha/beta acquired T cell response. On these grounds, understanding the mechanisms which prevent the maternal immune system from rejecting a semiallogenic foetus could be helpful to understand the development of some autoimmune diseases, and potentially to develop new targeted therapeutic strategies.

Microchimerism and human autoimmune diseases

Cells traffic in both directions between the fetus and the mother during pregnancy. Recent studies indicate that a low level of fetal cells commonly persists in the maternal circulation for years after pregnancy completion. The harboring of DNA or cells from another individual at low levels is called microchimerism. Chronic graft-vs-host disease is a condition of human chimerism that shares similarities to some autoimmune diseases and for which the specific HLA genes of donor and host are known to be of central importance. Considered together with the female predilection to autoimmunity, these observations led to the hypothesis that microchimerism and HLA genes of host and non-host cells are involved in autoimmune disease. The hypothesis also extends to men and females who have not been pregnant because there are other sources of microchimerism. Maternal cells are now know to persist in her progeny and microchimerism can also derive from a twin or from a blood transfusion. Studies of systemic sclerosis, primary biliary cirrhosis, Sjögrens syndrome, polymorpyhic eruption of pregnancy, myositis and thyroid disease have both lent support and raised doubts about the role of microchimerism in autoimmune disease.

Polymyositis as a manifestation of chronic graft-versus-host disease

OBJECTIVE

Chronic graft-versus-host disease (GVHD) after haematopoietic stem cell transplantation (HSCT) has similarities to some idiopathic autoimmune diseases, including polymyositis. To investigate the relationship between chronic GVHD and idiopathic myositis we conducted a detailed analysis of all cases of myositis occurring in a large series of HSCT patients.

METHODS

We conducted a retrospective chart review of all cases of myositis that developed in 7161 patients who underwent HSCT at the Fred Hutchinson Cancer Research Center between 1969 and 1999.

RESULTS

Among 1859 individuals who developed chronic GVHD, 12 developed myositis. No patients developed myositis without chronic GVHD. Myositis was first identified between 7 and 55 months after transplantation. In histopathology, electromyography, laboratory values and response to immunosuppressive therapy, the cases resembled idiopathic polymyositis. Autoantibodies were found in eight cases.

CONCLUSIONS

Myositis in the chronic GVHD population occurred with an incidence higher than expected by chance, suggesting that muscle may be a target tissue for chronic GVHD. Recent studies have implicated allogeneic cells persisting after maternal-fetal cell transfer in selected autoimmune diseases, including myositis. This report lends support to the possibility that both idiopathic myositis and chronic GVHD-related myositis could involve allo-autoimmune responses.

HLA relationships of pregnancy, microchimerism and autoimmune disease

Recent studies have established that there is bi-directional cell traffic between mother and fetus during pregnancy. Suprisingly, fetal cells have been found to persist in the maternal circulation for years after pregnancy. Maternal cells can also persist into adult life in her progeny. When cells from one individual are present in the body of another the term chimerism is used and a low level of non-host cells is referred to as microchimerism. Chronic graft-versus-host disease often occurs after stem cell transplantation, is a known condition of chimerism, and resembles spontaneously occurring autoimmune diseases including systemic sclerosis, Sjögren's syndrome, primary biliary cirrhosis and sometimes myositis and systemic lupus. Of central importance to the development of chronic graft-versus-host disease is the HLA relationship of host and donor cells. Considering this constellation of observations together led to the hypothesis that microchimerism and HLA-relationships are involved in the pathogenesis of some autoimmune diseases. Although much additional work is needed, results of initial studies provide support to the concept that non-host cells could participate in the pathogenesis of some autoimmune diseases.

From the simple detection of microchimerism in patients with autoimmune diseases to its implication in pathogenesis

Long-term persistence of fetal cells in parous women (fetal microchimerism, FM) as well as maternal cells in their offspring (maternal microchimerism, MM) have been reported. Systemic sclerosis (SSc), primary biliary cirrhosis (PBC), and Sjögren's syndrome (SS) share similar epidemiology with a predilection for females following childbearing years, with clinical similarities to chronic graft-versus-host disease, a known condition of chimerism. This led to the hypothesis that FM could be involved in the pathogenesis of autoimmune diseases. Initial investigations were conducted in SSc, where the hypothesis was supported by the more frequent occurrence and, quantitatively, a greater degree of FM in women with SSc compared to matched healthy women. Long-term persistence, however, of fetal cells in healthy women indicates that FM per se is not sufficient for causing SSc, but may be important in the context of other risk factors, such as genetic susceptibility and HLA relationship among host and nonhost cells. Contradictory results have recently been published for both PBC and SS and cause difficulty in drawing any conclusions about the role of FM in their pathogenesis. On the other hand, MM has been investigated as a risk factor in patients with systemic lupus (SLE) and juvenile dermatomyositis (JDM). A potential role of MM has been suggested in the pathogenesis of SLE. Recent publications also support the hypothesis that MM might lead to increased risks for JDM. In conclusion, contradictory results have been observed. This reflects a need for standardization of protocols and the selection of control populations. Detection of microchimerism has to be quantitatively studied in the context of genetic factors in order to study its relationship to the pathogenesis of autoimmune diseases.

Fetal cell microchimerism in tissue from multiple sites in women with systemic sclerosis

OBJECTIVE

The realization that fetal cells pass into the maternal circulation and can survive for many years has raised the question of whether fetal microchimerism can cause subsequent disease in the mother. Available data suggest that fetal-maternal transfusion may be related to some autoimmune diseases, notably systemic sclerosis (SSc). The goal of the current work was to identify and quantify tissue-specific fetal microchimerism in women with SSc.

METHODS

We analyzed multiple tissue specimens obtained at autopsy from women with SSc as well as women who had died of causes unrelated to autoimmunity, using fluorescence in situ hybridization to detect the presence of male cells in women with sons. Tissues analyzed included adrenal gland, heart, intestine, kidney, liver, lung, lymph node, pancreas, parathyroid, skin, and spleen.

RESULTS

Male cells were observed in tissue from at least 1 site in each woman with SSc and were found most frequently in spleen sections. After spleen, male cells were observed most frequently in lymph node, lung, adrenal gland, and skin tissue. The only tissue type in which male cells were not seen in any patient was pancreatic tissue. Male cells were not observed in tissue from women who had died of causes unrelated to autoimmunity.

CONCLUSION

The results of this study suggest that fetal cells migrate from the peripheral circulation into multiple organs in women with SSc. All of the women studied had previously given birth to sons, so it is likely that these cells are of fetal origin. While the relevance of this finding to the pathogenesis of SSc remains to be elucidated, the presence of fetal cells in internal organs suggests that they could play a role in disease pathogenesis and that they may preferentially sequester in the spleen. The presence of these male cells may also be a result of disease, possibly through the migration of terminally differentiated and/or progenitor cells to areas of tissue damage.

Microchimerism and hla relationships of pregnancy: Implications for autoimmune diseases

The application of molecular techniques to the study of human pregnancy has resulted in knowledge that the placenta is only a relative barrier to traffic of fetal and maternal cells. Moreover, long-term persistence of fetal cells in the maternal circulation and maternal cells in her progeny have been described. Harboring of cells from another individual is referred to as chimerism and microchimerism indicates low levels of non-host cells. The clinical features of a known condition of human chimerism, chronic graft-versus-host disease that occurs after stem cell transplantation, resemble spontaneously occurring autoimmune diseases including systemic sclerosis, Sjögren's syndrome, primary biliary cirrhosis, and sometimes myositis and systemic lupus. A critical determinant of chronic graft-versus-host disease is the HLA relationship of donor and host cells. When considered together, these observations have led to a new area of research investigating whether microchimerism and HLA-relationships are involved in the pathogenesis of some autoimmune diseases.

Knowledge, authority and identity: a prolegomenon to an epistemology of the clinic

Disputes about theory in bioethics almost invariably revolve around different understandings of morality or practical reasoning; I here suggest that the field would do well to become more explicitly contentious about knowledge, and start the task of putting together a clinical epistemology. By way of providing some motivation for such a discussion, I consider two cases of resistance to shifts in clinical practice that are, by and large, not ethically controversial, highlighting how different conceptions of epistemic authority may contribute to clinicians' unwillingness to adopt these changes, and sketching out some initial suggestions for epistemic analysis of clinical practice.

Forming professional bioethicists: the program at the University of Tennessee, Knoxville

As a way of contributing to bioethics' understanding of itself, and, more particularly, to invigorate conversation about how we can best educate future colleagues, we present here a sketch of the quarter-century-old graduate concentration in medical ethics housed in the Department of Philosophy at the University of Tennessee, Knoxville. Our hope is to incite other programs to share their histories, strategies, problems, and aspirations, so as to help the field as a whole get a clearer sense of how we are putting together our future, and of how we might best go about this important job.

HLA-DQA1*0501 is associated with diffuse systemic sclerosis in Caucasian men

OBJECTIVE

Systemic sclerosis (SSc) is uncommon in men, and relatively little is known about factors contributing to its pathogenesis in this population. In the current study, we investigated HLA class II alleles in men with SSc. We also investigated the hypothesis that HLA compatibility of the mother could be a risk factor for SSc in men.

METHODS

Sequence-specific oligonucleotide probe typing was used to determine DQA1, DQB1, and DRB1 alleles of SSc patients (50 men and 36 parous women), healthy controls (59 men and 80 parous women), 26 mothers of men with SSc, and 44 mothers of healthy men. All study subjects were Caucasian, and allele frequencies were compared with those of Caucasian controls from the Eleventh International Histocompatibility Workshop as well as those of local controls.

RESULTS

The DQA1*0501 allele was significantly increased among men with SSc compared with healthy men (odds ratio [OR] 2.3, P = 0.006, Pcorr = 0.04). DQA1*0501 was associated with diffuse SSc in men (OR 3.0, P = 0.004, Pcorr = 0.03), but not with limited SSc in men. Maternal HLA compatibility was not a risk factor for SSc in men.

CONCLUSION

Previous studies have shown associations of DRB1 alleles with SSc, but have rarely determined DQA1 allele frequencies. Our findings indicate that a specific DQA1 allele is associated with SSc, and that DRB1 associations may be due to linkage disequilibrium with DQA1. Moreover, by analyzing genetic susceptibility according to sex, we found that the contribution of HLA genes to the risk of SSc was substantially greater in men than in parous women.

The effect of task on determination of maximum phonational frequency range

The purpose of this study was to investigate if there was an effect of task on determination of maximum phonational frequency range (MPFR). Two tasks commonly used to elicit MPFR in clinical voice evaluations were compared. Normal adult females (N = 30) were examined. No statistically significant effect of task was found. Both tasks (glissando and discrete-step) were found to have a high positive correlation (0.84). Implications of the use of one task for determination of maximum phonational frequency range are discussed, as is the possibility of a task effect on determination of other voice parameters.

Reproductive ethics and the family

The phrase 'reproductive ethics', as used by bioethicists, typically refers to concerns over morally appropriate employment of assisted reproductive technologies and, perhaps somewhat less commonly, to issues arising from technologies that block conception or end pregnancies. I here recommend to the attention of the field a more commodious use of 'reproductive ethics', one that takes seriously how humans are brought into the world as moral and social beings, and not simply as biological individuals. As a focus for this expanded agenda, I examine prevalent disagreements over the patterns and sources of the responsibilities and prerogatives that help define family structures, both as these are reflected in assisted reproductive practices involving the purchase of gametes, and in U.S. legal controversies about whether parents, or family courts, should determine who has the right to a relationship with children.

Cutting edge: persistent fetal microchimerism in T lymphocytes is associated with HLA-DQA1*0501: implications in autoimmunity

The host's MHC genotype plays a critical role in susceptibility to autoimmune diseases. We previously proposed that persistent fetal microchimerism from pregnancy contributes to the pathogenesis of autoimmune diseases such as scleroderma. In the current study, we investigated whether the specific host MHC genotype is associated with persistent microchimerism among T lymphocytes in women with scleroderma and in healthy women. Fetal microchimerism among T lymphocytes was strongly associated with HLA DQA1*0501 of the mother (odds ratio (OR) = 13.5, p = 0.007, p corrected (pc) = 0.06) and even more strongly with DQA1*0501 of the son (OR = infinity; p = 0. 00002, pc = 0.0002). This is the first description of an association between persistent fetal microchimerism in maternal T lymphocytes and specific HLA class II alleles. Although the association was observed in both healthy women and in women with scleroderma, the finding suggests an additional route by which HLA genes might contribute to susceptibility to autoimmune disease.

Pulsed ultrasound enhances the killing of Escherichia coli biofilms by aminoglycoside antibiotics in vivo

Escherichia coli biofilms on two polyethylene disks were implanted subcutaneously into rabbits receiving systemic gentamicin. Ultrasound was applied for 24 h to one disk. Both disks were removed, and viable bacteria were counted. Pulsed ultrasound significantly reduced bacterial viability below that of nontreated biofilms without damage to the skin.

The evolution of vertebrate antigen receptors: a phylogenetic approach

Classical T cells, those with alpha beta T-cell receptors (TCRs), are an important component of the dominant paradigm for self-nonself immune recognition in vertebrates. alpha beta T cells recognize foreign peptide antigens when they are bound to MHC molecules on the surfaces of antigen-presenting cells. gamma delta T cells bear a similar receptor, and it is often assumed that these T cells also require specialized antigen-presenting molecules for immune recognition, which we term "indirect antigen recognition." B-cell receptors, or immunoglobulins, bind directly to antigens without the help of a specialized antigen-presenting molecule. Phylogenetically, it has been assumed that T-cell receptors and the genes that encode them are a monophyletic group, and that "indirect" antigen recognition evolved before the split into two types of TCR. Recently, however, it has been proposed that gamma delta-TCRs bind directly to antigens, as do immunoglobulins (Ig's). This calls into question the null hypothesis that indirect antigen recognition is a common characteristic of TCRs and, by extension, the hypothesis that all TCR gene sequences form a monophyletic group. To determine whether alternative explanations for antigen recognition and other historical relationships among TCR genes might be possible, we performed phylogenetic analyses on amino acid sequences of the constant and variable regions which encode the basic subunits of TCR and Ig molecules. We used both maximum-parsimony and genetic distance-based methods and could find no strong support for the hypothesis of TCR monophyly. Analyses of the constant region suggest that TCR gamma or delta sequences are the most ancient, implying that the ancestral immune cell was like a modern gamma delta T cell. From this gamma delta-like ancestor arose alpha beta T cells and B cells, implying that indirect antigen recognition is indeed a derived property of alpha beta-TCRs. Analyses of the variable regions are complicated by strong selection on antigen-binding sequences, but imply that direct antigen binding is the ancestral condition.

Microchimerism and scleroderma

It is now known that cells traffic between fetus and mother during normal human pregnancy. Moreover, fetal cells have been found to persist in the maternal peripheral blood for decades after childbirth. Chronic graft-versus-host disease, a known condition of chimerism that occurs after allogeneic hematopoietic stem cell transplantation has clinical similarities to some autoimmune diseases, including scleroderma (SSc). SSc has a predilection for women and an increased incidence in women following childbearing years. These observations when considered together with the longterm persistence of fetal cells led to the hypothesis that microchimerism is involved in autoimmune diseases such as SSc. Initial studies of women with SSc lend support to the hypothesis. Microchimerism, however, is also very common in healthy normals, and available data is not sufficient to be conclusive with respect to disease pathogenesis. Microchimerism can also occur due to engraftment from a blood transfusion, from a twin, or from the mother, sources that are applicable to men and women who have never been pregnant. The mechanism(s) by which microchimerism might contribute to SSc are not known, although some insight may be gained from studies of chimerism in transplantation biology. If microchimerism does contribute to the pathogenesis of autoimmune disorders such as SSc, it is likely that new therapeutic strategies could be developed.

Fetal microchimerism alone does not contribute to the induction of primary biliary cirrhosis

Microchimerism has been implicated in the etiology of autoimmune diseases. It has also been implicated in the induction/maintenance of fetal tolerance. We used polymerase chain reaction (PCR) analysis to determine whether microchimerism occurred in patients who subsequently developed primary biliary cirrhosis (PBC), and thus may be involved in its etiology. We performed PCR amplification of sequences unique to both the X and Y chromosomes from the livers of 37 women with PBC and 39 female controls using WAVE technology; a very sensitive technology based on an ion-pair reverse-phase high-performance liquid chromatography system. All patients were known to have had at least 1 son and it was confirmed that PBC was diagnosed after the birth of the son. Data were analyzed for both detection of the Y chromosome gene and the ratio of the yield of the Y chromosome PCR products to the X chromosome. The prevalence of Y chromosome detection in PBC was 26 of 37 (70%) compared with 28 of 39 (72%) in controls, and the ratio of Y chromosome to X chromosome was similar between the PBC and control groups, 0.402 +/- 0.143 vs. 0.271 +/- 0.055, respectively. Our results, using our more sensitive technology, showed that microchimerism is a very common event in human liver and supported the thesis that this may contribute to the induction/maintenance of fetal tolerance. However, although we cannot exclude the possibility that select fetal major histocompatibility complex (MHC) haplotypes might contribute to disease susceptibility, our data suggest that microchimerism by itself does not play a significant role in the development of PBC.