Impact of pregnancy on polyfunctional IgG and memory B cell responses to Tdap immunization

BACKGROUND

Maternal pertussis immunization using Tdap vaccine is recommended in many countries to protect newborns from severe post-natal infection. Immunological changes during pregnancy may influence the response to vaccines. The quality of IgG and memory B cell responses to Tdap immunization in pregnant women has not yet been described.

METHODS

The impact of pregnancy on the response to Tdap vaccination was assessed by comparing humoral immune responses in 42 pregnant and 39 non-pregnant women. The levels of serum pertussis antigens and tetanus toxoid-specific IgG, IgG subclasses, IgG Fc-mediated effector functions, as well as memory B cell frequencies were assessed before and at several time points after vaccination.

RESULTS

Tdap immunization induced similar levels of pertussis and tetanus-specific IgG and IgG subclasses in pregnant and non-pregnant women. Pregnant women produced IgG promoting complement deposition, and neutrophils and macrophages phagocytosis at levels comparable to non-pregnant women. They were also able to expand pertussis and tetanus-specific memory B cells at similar frequencies as non-pregnant women, suggesting equivalent "boostability". Higher levels of vaccine-specific IgG, IgG subclasses, and IgG Fc-mediated effector functions were detected in cord blood as compared to maternal blood, indicating efficient transport across the placenta.

CONCLUSIONS

This study demonstrates that pregnancy does not affect the quality of effector IgG and memory B cell responses to Tdap immunization and that polyfunctional IgG are efficiently transferred across the placenta.

REGISTRY'S URL AND THE TRIAL'S REGISTRATION NUMBER

ClinicalTrials.Gov (NCT03519373).

The human fetal thymus generates invariant effector γδ T cells

Tieppo et al. show that the human fetal thymus generates invariant γδ T cells with programmed effector functions. This is due to an intrinsic property of fetal HSPCs caused by high expression of the RNA-binding protein Lin28b.

In the mouse thymus, invariant γδ T cells are generated at well-defined times during development and acquire effector functions before exiting the thymus. However, whether such thymic programming and age-dependent generation of invariant γδ T cells occur in humans is not known. Here we found that, unlike postnatal γδ thymocytes, human fetal γδ thymocytes were functionally programmed (e.g., IFNγ, granzymes) and expressed low levels of terminal deoxynucleotidyl transferase (TdT). This low level of TdT resulted in a low number of N nucleotide insertions in the complementarity-determining region-3 (CDR3) of their TCR repertoire, allowing the usage of short homology repeats within the germline-encoded VDJ segments to generate invariant/public cytomegalovirus-reactive CDR3 sequences (TRGV8-TRJP1-CATWDTTGWFKIF, TRDV2-TRDD3-CACDTGGY, and TRDV1-TRDD3-CALGELGD). Furthermore, both the generation of invariant TCRs and the intrathymic acquisition of effector functions were due to an intrinsic property of fetal hematopoietic stem and precursor cells (HSPCs) caused by high expression of the RNA-binding protein Lin28b. In conclusion, our data indicate that the human fetal thymus generates, in an HSPC/Lin28b-dependent manner, invariant γδ T cells with programmed effector functions.

The Impact of Thyroid Disorders on Clinical Pregnancy Outcomes in a Real-World Study Setting

Background: Subclinical hypothyroidism (SCH) and thyroid autoimmunity (TAI) have been associated with poor clinical pregnancy outcomes. However, these outcomes also depend on a number of demographic and obstetric variables. Therefore, the aim of this study was to investigate the impact of thyroid disorders on these outcomes, after adjustment for associated demographic and obstetrical parameters. Methods: This is cross-sectional study including 1521 pregnant women who underwent work-up and follow-up in the Centre Hospitalier Universitaire (CHU) Saint-Pierre, Brussels, and had ongoing pregnancies. Thyroid function (thyrotropin [TSH], free thyroxine [fT4]) and TAI (thyroid peroxidase antibodies) was determined at median (Q1-Q3) 13 (11-17) weeks. Baseline parameters and the prevalence of poor clinical pregnancy outcomes were compared between controls (no TAI and TSH <2.51 mIU/L) and three study groups (isolated TAI [TSH <2.51 mIU/L], SCH1 [TSH 2.51-3.7 mIU/L], SCH2 [TSH >3.7 mIU/L]). The impact of the different thyroid groups and demographic/obstetric independent variables on six poor clinical pregnancy outcomes (preeclampsia, intrauterine growth restriction [IUGR], preterm birth, neonatal intensive care unit [NICU] admission, low birth weight, and macrosomia) was investigated in a logistic regression model. Treatment with thyroid hormone before and during pregnancy and assisted and multiple pregnancies were exclusion criteria. Results: In total, 79 preeclampsias (5.2%), 40 IUGRs (2.6%), 79 preterm births (5.2%), 10 admissions to NICU (0.66%), 74 low birth weights (4.9%), and 94 babies with macrosomia (6.2%) were documented. TAI was independently associated with NICU admission (adjusted odds ratio [aOR] 16.92 confidence interval [CI 3.36-85.29]; p < 0.001) and TSH, as a continuous variable in the whole range, with preeclampsia (aOR 1.97 [CI 1.18-3.31]; p = 0.010). Trends were present for an association between SCH2 and preeclampsia (aOR 16.73 [CI 1.43-196.42]; p = 0.025), and for SCH1with NICU admission and low birth weight (aOR 19.36 [CI 1.18-316.97]; p = 0.038 and 21.38 [CI 1.29-353.39]; p = 0.032, respectively). Conclusions: Pregnant women with TAI had a significantly higher risk of an admission of the baby to the NICU, and SCH tended to be associated with a higher risk of preeclampsia and low birth weight. Other poor clinical pregnancy outcomes were not associated with thyroid disorders, but with demographic and obstetric parameters.

TCR Sequencing Reveals the Distinct Development of Fetal and Adult Human Vγ9Vδ2 T Cells

Phosphoantigen-reactive Vγ9Vδ2 T cells represent the main innate human γδ T cell subset and dominate the fetal and adult peripheral blood γδ T cell repertoire. It has been hypothesized that adult blood Vγ9Vδ2 T cells find their origin in the fetus like it is established for mouse innate γδ T cells. To address this issue, we analyzed the CDR3 of the TCR of human blood and thymic Vγ9Vδ2 T cells from fetal until adult life. We first identified key differences in the CDR3 repertoire of fetal and adult blood Vγ9Vδ2 T cells, including in CDR3 features important for phosphoantigen reactivity. Next, we showed that most of these key adult CDR3 features were already present in the postnatal thymus and were further enhanced upon selection in vitro by the microbial-derived phosphoantigen (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate. Finally, we demonstrated that the generation of a fetal-type or adult-type Vγ9Vδ2 CDR3 repertoire is determined by the fetal and postnatal nature of the hematopoietic stem and precursor cell. Thus, our data indicate that fetal blood Vγ9Vδ2 T cells find their origin in the fetal thymus whereas adult blood Vγ9Vδ2 T cells are generated to a large degree independently after birth.

Atopobium vaginae intrapartum bacteremia: A case report with a literature review

Atopobium vaginae is an anaerobic Gram-positive bacterium recognized as a causative agent of bacterial vaginosis and associated with preterm delivery. Invasive infection and bacteremia have been rarely reported. We describe the case of a woman expecting her firstborn child who presented with a A. vaginae bacteremia during labor. Identification was performed using 16S rRNA gene sequencing. Both maternal and fetal outcomes were favorable due to the maternal treatment with amoxicillin-clavulanic acid. We identified three other cases in the literature with different fetal outcome. The genetic diversity of A. vaginae should be further explored in order to reveal potential strains with differential pathogenic potential.

Genu recurvatum following paediatric femoral diaphyseal - fracture : salter type v injury revisit

A 17-year old boy with a history of a right femoral shaft fracture, fixed with a reamed intramedullary nail four years earlier, presented with a 15° genu recurvatum deformity, presumably due to premature closure of the anterior proximal tibial physeal plate following a Salter type V injury. He was treated with a supra-tubercular anterior opening wedge osteotomy, fixed with two Puddu plates and grafted with bone matrix substitute. The patient went on to unite without complication, but came back to clinic six years later with anterior knee pain and patella infera. The paper discusses genu recurvatum after growth plate arrest and the various techniques to address the problem. Moving the tibial tubercle by including it in the osteotomy should be considered to avoid the complication of patella infera.

Unicondylar fractures of the distal femur

BACKGROUND

Unicondylar fractures of the distal femur are rare, complex, intra-articular fractures. The objective of this multicentre study was to assess the reduction and fixation of unicondylar fractures.

HYPOTHESIS

Anatomic reduction followed by strong fixation allows early rehabilitation therapy and provides good long-term outcomes.

MATERIAL AND METHODS

We studied 163 fractures included in two multicentre studies, of which one was retrospective (n=134) and the other prospective (n=29). Follow-up of at least 1 year was required for inclusion. The treatment was at the discretion of the surgeon. Outcome measures were the clinical results assessed using the International Knee Society (IKS) scores and presence after fracture healing of malunion with angulation, an articular surface step-off, and/or tibio-femoral malalignment.

RESULTS

Mean age of the study patients was 50.9 ± 24 years, and most patients were males with no previous history of knee disorders. The fracture was due to a high-energy trauma in 51% of cases; 17% of patients had compound fractures and 44% multiple fractures or injuries. The lateral and medial condyles were equally affected. The fracture line was sagittal in 82% of cases and coronal (Hoffa fracture) in 18% of cases. Non-operative treatment was used in 5% of cases and internal fixation in 95% of cases, with either direct screw or buttress-plate fixation for the sagittal fractures and either direct or indirect screw fixation for the coronal fractures. After treatment of the fracture, 15% of patients had articular malunion due to insufficient reduction, with either valgus-varus (10%) or flexion-recurvatum (5%) deformity; and 12% of patients had an articular step-off visible on the antero-posterior or lateral radiograph. Rehabilitation therapy was started immediately in 65% of patients. Time to full weight bearing was 90 days and time to fracture healing 120 days. Complications consisted of disassembly of the construct (2%), avascular necrosis of the condyle (2%), and arthrolysis (5%). The material was removed in 11% of patients. At last follow-up, the IKS knee score was 71 ± 20 and the IKS function score 64 ± 7; flexion range was 106 ± 28° (<90° in 27% of patients); and 12% of patients had knee osteoarthritis.

CONCLUSION

Anatomic reduction of unicondylar distal femoral fractures via an appropriate surgical approach, followed by stable internal fixation using either multiple large-diameter screws or a buttress-plate, allows immediate mobilisation, which in turn ensures good long-term outcomes.

LEVEL OF EVIDENCE

IV, cohort study.

Long-term quality of life after en-bloc vertebrectomy: 25 patients followed up for 9 years

OBJECTIVE

Assess quality-of-life results in patients who have undergone extensive curative surgery for spinal tumor and compare them to the general population in France.

INTRODUCTION

Life expectancy is not the only criterion to assess the outcomes after massive tumor resections. Residual quality of life is also crucial. An indication for major surgery for spinal tumor should take the patient's long-term functional status into account, but the literature is limited on this question.

MATERIALS AND METHODS

Twenty-five living patients from a group of 120 operated were assessed, all of whom were operated on by the same surgeon between 1984 and 2007. The mean follow-up was 9 years (range, 3-25 years). The mean age at surgery was 49 years. The patients completed different functional and quality-of-life questionnaires: the Oswestry Disability Index version 2 (ODI), the PROLO, the Karnofsky Index of performance status (KI), the Eastern Cooperative Oncology Group performance status (ECOG), the Short Form-36 Health Survey (SF-36), and the EuroQol-5 Dimensions (EQ5D). In addition, each patient was clinically and radiographically evaluated. Subgroups were identified considering the number of levels resected and histology. Their results on the SF-36 were compared with the results from the general population in France.

RESULTS

The mean PCS (physical component summary of the SF-36) was 52.4, the MCS (mental component summary, the psychological component of the SF-36) was 47.7, the ODI was 18.2, the PROLO was 7, the ECOG was 1, and the KI was 80%. The resections at three levels were associated with worse results in terms of quality of life, but overall, the results were similar to the French general population data for all categories of the SF-36.

CONCLUSION

Appropriate indications for massive spinal resection give good oncological and functional results. Although the expected life expectancy justifies this aggressive surgery, postoperative quality of life shows that it can also be successful on a functional level.

LEVEL OF EVIDENCE

Level IV; retrospective clinical study.

An audit about labour induction, using prostaglandin, in women with a scarred uterus

OBJECTIVES

Induction of labour after a previous caesarean section is still controversial. We aim to analyse, in a population of women who have a uterine scar, the maternal, foetal and neonatal complications in relation to the mode of labour and delivery.

STUDY DESIGN

Retrospective analysis of collected data from all the singleton deliveries of patients with a scarred uterus (N=798), admitted to the hospital between August 2006 and March 2009.

OUTCOMES

maternal and perinatal complications.

RESULTS

Among 798 singleton deliveries, 36.1% had a spontaneous labour, 12.6% a prostaglandin-induced labour and 2.9% an ocytocin-induced labour, and 48.4% had an elective caesarean section. The chance of delivering vaginally was respectively 84.4% for those who had a spontaneous labour, 75.2% for those who were induced using prostaglandin, 82.6% after induction using ocytocin. There were eight uterine ruptures, four after spontaneous labour (1.4%), two after prostaglandin induction (2%) and two at the time of an iterative caesarean section (0.5%). There were no differences between groups, except the risk of haemorrhage (17.4% after spontaneously induced labour, 34.8% after ocytocin, 17.8% after prostaglandin and 44.6% after iterative caesarean section; p<0.005) and the neonatal admissions when analysed by intention to treat only (8.3% after spontaneously induced labour, 9.1% after ocytocin, 12% after prostaglandin and 16.8% after iterative caesarean section; p<0.009).

CONCLUSION

Although no increase in maternal or perinatal outcome was observed in relation to prostaglandin-induced labour after caesarean section, this study is too underpowered to exclude an increased risk.

Total hip arthroplasty dislocation rate following isolated cup revision using Hueter's direct anterior approach on a fracture table

INTRODUCTION

Instability is a major complication after revision total hip arthroplasty. Studies in the literature have shown that the dislocation rate after primary arthroplasties by anterior approach on a fracture table is satisfactory, but the rate of instability following revision surgery is not known.

HYPOTHESIS AND AIMS

We hypothesized that the Hueter direct anterior approach would result in a lower rate of postoperative dislocation following revision surgery. This hypothesis was tested in a series of isolated acetabular component replacements.

PATIENTS AND METHODS

Seventy-three consecutive isolated acetabular component replacements were performed between January 2000 and December 2007. Twelve revisions using constrained liners or dual mobility cups were excluded, thus 61 revisions in 59 patients, mean age 65.8-year-old (range 27-86) were included. The indications for revision arthroplasty were: 51 (83.6%) cases of aseptic loosening, five (8.2%) non-integration of cementless cups, three (4.9%) cases of instability, one (1.6%) case of impingement with the psoas and one (1.6%) case of excessive (3cm) lengthening. Acetabular bone defects were moderate, with 12 stage I, 26 stage II, 19 stage III, and only four stage IV defects on the SOFCOT bone stock deficiency score. There was no acetabular reconstruction in 18 cases, while there were four isolated reconstruction cages and 39 cages with a graft. The replacement cup was cemented in 52 cases and cementless in nine. Inclination and anteversion were measured by the Pradhan method on standard X-rays.

RESULTS

Results were evaluated after a mean follow-up of 2.4 years±1.7 years (1-7 years). Four dislocations were observed (6.6%) all anterior and early in the postoperative period (less than 2 months): three patients had a single episode of dislocation and one patient again underwent revision cup replacement by Hueter anterior approach for recurrent anterior dislocation. The only factor associated with a risk of dislocation was a high body mass index: 29.7±0.8 in the group with dislocation compared to 25.6±3.2 in the group without (P=0.008). A high number of prior interventions was also a significant risk factor (P=0.045). On the other hand, there was no difference in cup inclination or femoral offset between the group with dislocation and that without.

DISCUSSION

Although the rate of dislocation is higher than after primary THA by anterior approach, it remains acceptable for revision THA and is similar to rates observed with other approaches. The literature does not clearly establish that one surgical approach is better than another in terms of instability. This study was limited by the absence of CT-scan measurements of component orientation both preoperatively to evaluate the femoral component which is preserved, as well as during follow-up to evaluate cup angle and compare the groups with and without dislocation.

CONCLUSION

The Hueter direct anterior approach is a viable option for isolated cup revision, as long as femoral loosening has been excluded, and the orientation of the preserved femoral component is known.

LEVEL OF EVIDENCE

Level IV; retrospective study.

Cranial nerves neuropraxia after shoulder arthroscopy in beach chair position

We report a case of neuropraxia of the 9th, 10th and 12th cranial nerve pairs after arthroscopic rotator cuff repair in the beach chair position. The elements in the medical file seem to exclude an intracranial cause of the lesions and support a mechanical, extracranial cause due to intubation and/or the beach chair position. This clinical case report shows the neurological risks of the beach chair position during arthroscopic shoulder surgery and presents the essential safety measures to prevent these risks.

Occurrence of noise in alumina-on-alumina total hip arthroplasty. A survey on 284 consecutive hips

BACKGROUND

Alumina-on-alumina bearings have been accepted as a valuable alternative for young and active patients. Alumina fractures, and socket loosening were the main complications reported. But, with the increasing number of prostheses implanted, noise occurrence appeared as a new concern. The primary aim of the present study was to quantify the prevalence of noticing noise in a population having received alumina-on-alumina total hip arthroplasty as well as its eventual impact on outcome.

PATIENTS AND METHODS

Two hundred and eighty-four ceramic-on-ceramic hips were performed in 238 patients from January 2003 to December 2004. The average age was 52.4 ± 13.4 years (range, 13 to 74 years). All the hips received the same prosthesis (Ceraver-Osteal™) with alumina bearing components (Ceraver-Osteal™): 32 mm liners were used for cups of 50mm or larger and 28 mm liners for cups smaller than 48 mm; the minimal alumina thickness was 6mm. The acetabular component (Cerafit™) was hemispherical, coated with a hydroxyapatite layer and press-fit fixed. The stem (Cerafit™) was a straight tapered cementless stem, fully coated with a hydroxyapatite layer. Clearance between femoral head and liner was between 20 and 50 microns. A retrospective survey was conducted by an independent surgeon who did not participate to surgery in 2007. He conducted phone interviews of patients using a standard questionnaire. No suggestion was offered on how they could describe the noise and they felt free to use the word that they considered to be the most adapted. Satisfaction was evaluated. When the noise was present, X-rays were taken to assess if sign of bearings fracture was present.

RESULTS

Four patients (six hips) died of unrelated causes during the follow-up period. Three patients (three hips) live outside France and could not be followed (1.3%). Nine patients (10 hips) could not be traced and were considered lost to follow-up (3.8%). Two hundred and twenty-two patients with 265 hips, therefore, were included (nine using bearing components in 28 mm diameter and 265 in 32 mm). Twenty-eight hips experienced noise generation (10.6%). It was defined as a snap for six patients, as a cracking sound by six, as rustling by six patients, as a squeaking by seven patients (2.6%), a tinkling by two patients, one patient was unable to define the sound she felt. No factor related to the patient influenced the occurrence of noise. Twelve patients were dissatisfied with the result of their hip prosthesis, five of them experienced noise (41.7%); 210 were satisfied or very satisfied, 23 of them experiencing noise (11%); this difference was significant (P=0.002).

CONCLUSION

The origins of noise occurrence are unknown. Squeaking may be related to generation of stripe wear and absence of sufficient lubrication. Other types of noise can be due to microseparation, occult dislocation, impingement between the femoral neck and the acetabular rim.

LEVEL OF EVIDENCE

Level IV. Retrospective study.

Trehalose induces resistance to powdery mildew in wheat

• Reduction in the degree of powdery mildew infection of wheat leaves is observed after treatments with trehalose, a nonreducing disaccharide commonly found in a wide variety of organisms, including fungi. • Wheat (Triticum aestivum) cv. Sideral plants grown in phytotrons were inoculated with Blumeria graminis f.sp. tritici. In addition to degree of infection, the effect of trehalose solution was further investigated using light and fluorescence microscopy and enzyme assays. • Infection in wheat leaves was reduced by 50 and 95% with trehalose solution (15 g l^-1 ) following a single spraying and three sprayings, respectively; in a detached leaf assay, trehalose was effective at concentrations as low as 0.01 g l^-1 . Trehalose did not inhibit conidial germination and differentiation of appressoria (in vitro or on the leaf epidermis), but enhanced papilla deposition in epidermal cells. Trehalose also enhanced phenylalanine ammonia-lyase (PAL) and peroxidase (PO) activities; both markers of plant defence responses. However, the level of three cinnamyl alcohol dehydrogenase (CAD) activities (conyferyl, p-coumaryl and sinapyl alcohol dehydrogenase) was unchanged. • Trehalose treatment of wheat confers resistance to B. graminis infection by activating plant defence responses (e.g. papilla deposition, PAL and PO activities).