Multilevel human secondary lymphoid immune system compartmentalization revealed by complementary imaging approaches

Secondary human lymphoid tissue immune reactions take place in a highly coordinated environment with compartmentalization representing a fundamental feature of this organization. In situ profiling methodologies are indispensable for the understanding of this compartmentalization. Here, we propose a complementary experimental approach aiming to reveal different aspects of this process. The analysis of human tonsils, using a combination of single cell phenotypic analysis based on flow cytometry and multiplex imaging and mass spectrometry-based methodologies, revealed a compartmentalized organization at the cellular and molecular levels. More specifically, the skewed distribution of highly specialized immune cell subsets and relevant soluble mediators was accompanied by a compartmentalized localization of several lipids across different anatomical areas of the tonsillar tissue. The performance of such combinatorial experimental approaches could lead to the identification of novel in situ interactions and molecular targets for the in vivo manipulation of lymphoid organ, particularly the germinal center, immune reactions.

Trispecific antibody targeting HIV-1 and T cells activates and eliminates latently-infected cells in HIV/SHIV infections

Agents that can simultaneously activate latent HIV, increase immune activation and enhance the killing of latently-infected cells represent promising approaches for HIV cure. Here, we develop and evaluate a trispecific antibody (Ab), N6/αCD3-αCD28, that targets three independent proteins: (1) the HIV envelope via the broadly reactive CD4-binding site Ab, N6; (2) the T cell antigen CD3; and (3) the co-stimulatory molecule CD28. We find that the trispecific significantly increases antigen-specific T-cell activation and cytokine release in both CD4+ and CD8+ T cells. Co-culturing CD4+ with autologous CD8+ T cells from ART-suppressed HIV+ donors with N6/αCD3-αCD28, results in activation of latently-infected cells and their elimination by activated CD8+ T cells. This trispecific antibody mediates CD4+ and CD8+ T-cell activation in non-human primates and is well tolerated in vivo. This HIV-directed antibody therefore merits further development as a potential intervention for the eradication of latent HIV infection.

The role of thyroid function in female and male infertility: a narrative review

PURPOSE

We herein aimed to review the new insights into the impact of impaired thyroid function on male and female fertility, spacing from spontaneous pregnancy to ART, with the objective of providing an updated narrative revision of the literature.

METHODS

This narrative review was performed for all available prospective, retrospective and review articles, published up to 2021 in PubMed. Data were extracted from the text and from the tables of the manuscript.

RESULTS

Thyroid dysfunction is frequently associated with female infertility, whereas its link with male infertility is debated. Female wise, impaired function is detrimental to obstetric and fetal outcomes both in spontaneous pregnancies and in those achieved thanks to assisted reproduction technologies (ART). Furthermore, the reference range of TSH in natural pregnancy and ART procedures has recently become a matter of debate following recent reports in this field. On the other hand, the impact of thyroid function on the male reproductive system is less clear, although a possible role is suggested via modulation of Sertoli and Leydig cells function and spermatogenesis.

CONCLUSION

Thyroid function should be carefully monitored in both male and female, in couples seeking spontaneous pregnancy as well as ART, as treatment is generally immediate and likely to improve chances of success.

P-773 Assessment of the putative impact of culture strategies, oocyte/embryo manipulations, and operators: a retrospective analysis of 3705 blastocyst culture cycles and 2604 single blastocyst transfers

Study question

Do the culture strategies, oocyte/embryo manipulations, and operators impact blastulation-rates per cohort of metaphase-II oocytes (BR per MII-oocytes) and/or live-birth-rates per single-embryo-transfer (LBR per SET)?

Summary answer

Undisturbed culture improved the BR per MII-oocytes, while culture drop volumes ≥80ml in the well-of-the-well system were associated with increased LBR per untested/euploid blastocyst SET.

What is known already

IVF lab performance is critical to achieve success in IVF. Yet, while a consensus exists on the main key-performance-indicators (KPIs), namely BR and LBR, and their inherent benchmark values, the strategies to fulfil them are still poorly standardized. The plasticity of human embryos along with the disparities in the patient populations might mask even largely different outcomes across clinics. Therefore, clear guidelines shall outline which procedures to standardize and carefully monitor in IVF laboratories. Here we investigated different embryo culture strategies, manipulations, and operators for their effect on BR and LBR per SET, adjusting the results for all main confounders.

Study design, size, duration

Retrospective analysis of 3705 cycles with ≥1 MII-oocyte and 2604 SETs (January2019-March2021). BR per MII-oocytes and LBR per SET were the main outcomes. Embryo-twinning was also assessed. The putative impact of culture strategies, manipulations, and operators’ expertise (0-5yr,6-11yr or > 12yr) was determined via regression analyses adjusted for possible confounders (autologous/donated oocytes, age, primary/secondary infertility and duration, sperm factor; for SET: also endometrial preparation, age at transfer, number of consecutive transfer, untested/euploid blastocyst, quality, and day).

Participants/materials, setting, methods

In donation cycles, only vitrified oocytes were used. In Preimplantation-Genetic-Testing (PGT) cycles, no assisted-hatching was performed and only euploid non-mosaic vitrified-warmed blastocysts were transferred. The culture strategies assessed were undisturbed (Embryoscope, Geri and Embryoscope-plus)/disturbed (KSystems), volume and approach (drops ≤30ml with single-culture or ≥ 80ml with well-of-the-well approaches), humidified/non-humidified atmosphere and media refreshed/not-refreshed. The manipulations assessed were oocyte/blastocyst vitrification (performed/not-performed), oocyte retrieval and denudation performed with oil overlay (yes/not), laser-assisted artificial-shrinkage (performed/not-performed), trophectoderm biopsy (performed/not-performed).

Main results and the role of chance

The only confounders on BR per MII-oocytes (overall:39.1±26.6%) were sperm factor and oocyte age. The linear regressions showed benefits for humidified atmosphere (unstandardized B-coefficient:+2.9%, p = 0.01), manipulations with oil overlay (+3.9%, p = 0.03) and drops≥80ml with a well-of-the-well approach (+4.3%, p < 0.01). However, only the positive effect of undisturbed incubators was significant when adjusting for confounders [41.7±27.8% (N = 1440 cycles) versus 37.5±25.7% in a disturbed incubator (N = 2265 cycles); unstandardized B-coefficient:+5.6%, 95%CI +3.9% to + 7.3%, standardized beta-coefficient:-0.103,p<0.01].

The main confounders on LBR per SET (overall: N = 1044/2604, 40.1%) were oocyte age, number of consecutive transfer, blastocyst chromosomal status (untested/euploid), quality and day. The univariate logistic regressions showed a benefit for undisturbed incubators (OR:1.3, 95%CI 1.1-1.5, p < 0.01), humidified atmosphere (OR:1.4, 95%CI 1.1-1.7, p < 0.01) and media refresh (OR:1.3, 95% 1.01-1.8, p = 0.05). However, only the use of drops ≥80ml with a well-of-the-well approach rather than drops ≤30ml with a single-culture approach involved an improvement when adjusting for confounders (untested SETs: N = 71/171, 41.5% versus N = 434/1284, 33.8%; euploid SETs: N = 170/316, 53.8% versus N = 369/833, 44.3%; multivariate-OR:1.33, 95%CI 1.12-1.58, adjusted p-value<0.01). This result was confirmed in a sub-analysis across only first patients’ SETs.

Lastly, no feature under investigation was associated with embryo-twinning (overall: N = 23/1243, 1.9% and N = 14/1044, 1.3% per pregnancy and delivery, respectively).

Limitations, reasons for caution

Retrospective single center study. Only ICSI cycles and continuous culture media were assessed. Cleavage stage SETs were excluded. All operators had at least 3yr of experience. Perinatal and gestational outcomes were not evaluated.

Wider implications of the findings

Real-life data adjusted for confounders may unveil fluctuations in critical KPIs mainly imputable to culture strategies. An impact seldom derives from oocyte/embryo manipulations if experienced operators adopt validated protocols. An accurate interpretation of these evidence shall lead to properly designed studies with problem-solving/progress-building purposes, and guidelines to standardize culture practices.

Trial registration number

Not applicable

P-389 Elevated BMI in oocyte donors or recipients is associated with a higher risk of miscarriage after blastocyst transfer: a multicenter analysis of 1544 procedures

Study question

Is an elevated BMI in either oocyte donors or recipients associated with a higher risk of miscarriage after blastocyst transfer?

Summary answer

Overweight in oocyte donors and/or obesity in recipients are associated with a 2X-higher risk of miscarriage in egg donation cycles.

What is known already

Several basic-science, clinical and epidemiological studies revealed an association between BMI and infertility, suggesting a J-shaped relationship: both underweight and especially overweight/obese women can suffer from reproductive impairments. In particular, overweight-obese women are more prone to suffer from a miscarriage even when euploid blastocysts are transferred. Yet, it is still unclear whether this is the consequence of an altered oocyte (and then embryonic) competence and/or an impaired endometrial receptivity. In this context, oocyte donation cycles represent the ideal clinical setting to shed some light on an issue with numerous social, clinical, and logistic implications.

Study design, size, duration

Retrospective study including 1544 blastocyst single embryo transfers (SETs) conducted in oocyte donation cycles (Jan2019-May2021). All oocytes were vitrified at 2 egg banks in Spain and warmed at 8 clinics part of the same network. The primary outcome was the miscarriage rate (<22nd gestational weeks) per clinical pregnancy according to donors’ and/or recipients’ BMI. Four BMI clusters were defined (underweight: <18.5; normal-weight: 18.5-24.9; over-weight: 25-30; obese: >30).

Participants/materials, setting, methods

66.1%,4.9%,20.3% and 8.7% of SETs were conducted in normal-weight, underweight, overweight, and obese recipients. 81.4%,4.5% and 14.1% of SETs with oocytes derived from normal-weight, underweight, and overweight donors. The putative confounders investigated were egg bank, IVF center, fresh/vitrified-warmed SET, blastocyst quality/day, recipient/donor age, endometrial preparation protocol, number of consecutive SET. Before SET, we requested blood test for infections and TORCH, thyroid function, coagulation and immunological assessment, cardiological, gynecologic and breast evaluation.

Main results and the role of chance

Overweight-obese recipients were slightly older (43.0±4.0yr) than normal-weight ones (42.2±3.8yr; p < 0.01). Similarly, overweight donors were slightly older (27.5±4.5yr) than normal-weight ones (26.4±4.3yr; p < 0.01). Therefore, all outcomes were adjusted for recipients’/donors’ age. The overall positive pregnancy rate per blastocyst SET and biochemical pregnancy loss rate were 51.8% and 12.6%. No association was reported between either recipients’ or donors’ BMI and both these secondary outcomes. Conversely, higher recipients’ and donors’ BMI were significantly associated with a higher risk of miscarriage after blastocyst SET (multivariate-OR 1.05, 95%CI 1.01-1.1, adjusted-p=0.05; multivariate-OR 1.1, 95%CI 1.04-1.2, adjusted-p<0.01). The most significant differences were reported for obese versus normal-weight recipients (N = 18/64,28.1% versus N = 73/448,16.3%; p = 0.03, power=60%; multivariate-OR 1.8, 95%CI 1.01-3.4, adjusted-p=0.05) and for overweight versus normo-weight donors (N = 31/111,27.9% versus N = 94/561,16.8%; p < 0.01, power=73%; multivariate-OR 1.9, 95%CI 1.16-3.0, adjusted-p=0.01). In the 14 clinical pregnancies where the oocytes derived from overweight donors and the blastocysts were transferred to obese women the miscarriage rate was 50%; the same outcome in normal-weight recipients using oocytes from normal-weight donors was 15% (N = 55/366; p < 0.01, power=85%; OR 5.6, 95%CI 1.8-16.8, p < 0.01). The data were similar across both egg banks and all IVF centers. All other parameters assessed were not associated with the primary outcome under investigation.

Limitations, reasons for caution

The study is retrospective, and the sample size in each sub-group shall be increased. Moreover, BMI is a gross marker of an individual’s metabolic status. Future studies on more accurate markers like percentage and localization of adipose tissue assessed through techniques like bioelectrical impedance analyses are desirable.

Wider implications of the findings

Both oocyte competence and endometrial receptivity might be impaired from unbalanced nutritional intakes. More studies on this topic are certainly required. Whenever possible, nutritional/lifestyle adjustments should be encouraged in obese patients because of their higher risk of miscarriage, and a BMI limit should be considered also when recruiting egg donors.

Trial registration number

Not applicable

O-121 Uncovering the value of day 7 blastocysts using artificial intelligence on time lapse videos

Study question

Which is the clinical value of day 7 blastocysts?

Summary answer

Ending embryo culture at 144 hours-post-insemination (hpi) would involve7.3%- and 4.4%-relative reductions in the patients obtaining euploid blastocysts and live birth(s)(LBs), respectively.

What is known already

Many studies showed that day 7 blastocysts are clinically valuable although less euploid and less competent than faster growing embryos. Nevertheless, a large variability exists in: (i) the definition of “day 7”; (ii) the criteria to culture embryos to day 7; (iii)the clinical setting; (iv) the local regulation; and/or (v) the culture strategies and incubators. Here,we aimed at ironing out these differences and portray day 7 blastocysts with the lowest possible risk of bias. To this end, we have also adopted an artificial intelligence (AI)-powered software to automatize developmental timings annotations and standardize embryo morphological assessment.

Study design, size, duration

Observational study including 1966 blastocysts obtained from 681 patients cultured in a time lapse incubator between January 2013 and December 2020 at a private Italian IVF center.

Participants/materials, setting, methods

Trophectoderm biopsy without hatching and comprehensive-chromosome-testing were performed. Blastocysts were clustered in six groups based on the time-of-biopsy every 12hr from <120hpi (control) to > 168hpi. Blastocyst quality, time-of-expanding-blastocyst (tEB) and duration of expansion were annotated through AI and confirmed manually. The main outcomes were euploidy-rate and LB-rate (LBR) per transfer. Lastly, patients obtaining (euploid) blastocysts, LBs, and supernumerary blastocysts, were reported based on a hypothetical 144hpi cut-off, and all relative reductions calculated.

Main results and the role of chance

14.6% of the blastocysts reached full expansionbeyond 144hpi (5.9% between 144-156hpi, 7.9% between 156-168hpi, and 0.8% >168hpi). Slower blastocysts were of a worse quality based on the evaluation of both embryologists and AI. Both longer tEB and a longer duration of expansion concurred to day7 development, quite independently of embryo quality. The lower euploidy rate among day7 blastocysts is due to their worse morphology and more advanced oocyte age, rather than to a slower development per se. Conversely, the lower LBR was significant even after adjusting for confounders, with a first relevant decrease for blastocysts biopsied in the range 132-144hpi (N = 76/208, 36.5% versus N = 114/215, 53.0% in the control, multivariate-OR: 0.61, 95%CI 0.40-0.92, adjusted-p=0.02), and a second step for blastocysts biopsied in the range 156-168hpi (N = 3/21, 14.3%, multivariate-OR:0.24, 95%CI 0.07-0.88, adjusted-p=0.03). Nevertheless, when the cut-off was set at 144hpi, no significant difference was reported. In this patient population, ending embryo culture at 144hpi would have caused 10.6%-, 7.3%-, 4.4%-, 13.7%-, and 5.2%-relative reductions in the number ofpatients obtaining blastocysts, euploid blastocysts, LBs, supernumerary blastocysts without a LB and after a LB, respectively.

Limitations, reasons for caution

Gestational and perinatal outcomes were not assessed, and a cost-effectiveness analysis was not performed. We encourage the production of these data in other clinical settings and regulatory contexts.

Wider implications of the findings

Day7 culture shall be supported following a careful case-by-case evaluation. Patients shall be aware of their lower competence, yet day7 blastocysts are valuable for poor-prognosis couples, couples less compliant towards other attempts in case of failures, and couples wishing for second children. AI may improve the generalizability of these evidence.

Trial registration number

Not applicable

The effect of extended cryo-storage following vitrification on embryo competence: a systematic review and meta-analysis

PURPOSE

Few studies explored whether prolonged cryo-storage after vitrification affects embryo competence and perinatal outcomes. This systematic review and meta-analysis aims at highlighting any putative impact of cryo-storage duration on cryo-survival, miscarriage, live birth and major malformations.

METHODS

A systematic review was performed using MEDLINE (PubMed), ISI Web of Knowledge, Scopus and Embase databases up to June 2021. Data were combined to obtain a pooled OR, and meta-analysis was conducted using a random effects model. Out of 1,389 screened abstracts, 22 papers were assessed for eligibility, and 5 studies were included (N = 18,047 embryos). Prolonged cryo-storage was defined as > 12 months (N = 3389 embryos). Subgroup analysis was performed for untested vitrified cleavage stage embryos (N = 1739 embryos) and for untested and euploid vitrified blastocysts (N = 13,596 and 2712 embryos, respectively).

RESULTS

Survival rate, miscarriage, live birth and major malformation rates were all similar in the two groups.

CONCLUSION

These data further support the safety of long-term cryo-storage of human embryos beyond 12 months. This is reassuring for good prognosis patients with surplus embryos, couples seeking a second child from supernumerary embryos and women postponing the transfer for clinical or personal reasons.

Potent anti-viral activity of a trispecific HIV neutralizing antibody in SHIV-infected monkeys

Broadly neutralizing antibodies (bNAbs) represent an alternative to drug therapy for the treatment of HIV-1 infection. Immunotherapy with single bNAbs often leads to emergence of escape variants, suggesting a potential benefit of combination bNAb therapy. Here, a trispecific bNAb reduces viremia 100- to 1000-fold in viremic SHIV-infected macaques. After treatment discontinuation, viremia rebounds transiently and returns to low levels, through CD8-mediated immune control. These viruses remain sensitive to the trispecific antibody, despite loss of sensitivity to one of the parental bNAbs. Similarly, the trispecific bNAb suppresses the emergence of resistance in viruses derived from HIV-1-infected subjects, in contrast to parental bNAbs. Trispecific HIV-1 neutralizing antibodies, therefore, mediate potent antiviral activity in vivo and may minimize the potential for immune escape.

Concordance of immunological events between intrarectal and intravenous SHIVAD8-EO infection when assessed by Fiebig-equivalent staging

Primary HIV-1 infection can be classified into six Fiebig stages based on virological and serological laboratory testing, whereas simian-HIV (SHIV) infection in nonhuman primates (NHPs) is defined in time post-infection, making it difficult to extrapolate NHP experiments to the clinics. We identified and extensively characterized the Fiebig-equivalent stages in NHPs challenged intrarectally or intravenously with SHIVAD8-EO. During the first month post-challenge, intrarectally challenged monkeys were up to 1 week delayed in progression through stages. However, regardless of the challenge route, stages I-II predominated before, and stages V-VI predominated after, peak viremia. Decrease in lymph node (LN) CD4+ T cell frequency and rise in CD8+ T cells occurred at stage V. LN virus-specific CD8+ T cell responses, dominated by degranulation and TNF, were first detected at stage V and increased at stage VI. A similar late elevation in follicular CXCR5+ CD8+ T cells occurred, consistent with higher plasma CXCL13 levels at these stages. LN SHIVAD8-EO RNA+ cells were present at stage II, but appeared to decline at stage VI when virions accumulated in follicles. Fiebig-equivalent staging of SHIVAD8-EO infection revealed concordance of immunological events between intrarectal and intravenous infection despite different infection progressions, and can inform comparisons of NHP studies with clinical data.

P–752 Embryo morphological grading across several IVF centers is not consistent but an interactive training is useful to improve its consistency

Study question

Are the embryologists across several IVF clinics concordant when evaluating embryo morphology?

Summary answer

Embryo morphological grading is sufficiently consistent among embryologists from the same center, while an interactive training was essential to improve its accuracy across several clinics.

What is known already

Embryo morphology, mostly at the blastocyst stage, is the strongest non-invasive embryological feature that associates with implantation potential. This association is confirmed also when euploid blastocysts are transferred. At present, several embryo grading schemes exist but is still unclear which is the most effective among them. Moreover, many IVF clinics adopt internal embryo grading scores, further limiting the transferability of this crucial prognostic information across different laboratories. With the aim of assessing the level of concordance in embryo grading within and between IVF clinics, the Italian Society of Embryology, Reproduction and Research (SIERR) conceived this study.

Study design, size, duration

We photographed 40 cleavage-stage and 40 blastocyst-stage embryos (3 focal-planes=240 photos). Two embryologists (senior and junior) from 65 Italian IVF clinics were invited to grade them. Their evaluations were blindly collected as Phase-I (January2020-March2020). Phase-II consisted of an interactive-training on Google-Classroom during which 6 selected experts found a Consensus on the morphological evaluation of the 80 embryos (April2020). As Phase III (May2020-July2020), a second set of 240 pictures was sent to senior participants and experts.

Participants/materials, setting, methods

Eighteen centers agreed to participate, and 36 embryologists were included. The embryo grading scheme adopted was the Alpha-ESHRE Istanbul Consensus (parameters: cleavage-stage blastomeres’ symmetry and fragmentation, blastocyst’s expansion, inner-cell-mass and trophectoderm quality), conventionally used in 50% of the centers (N = 9/18). The concordance within (junior versus senior) and between (senior versus experts) centers was calculated through the Cohen’s-k. The concordance between centers was compared before and after the interactive training on the two sets of pictures.

Main results and the role of chance

The centers and embryologists included were representative of the Italian IVF scenario: oocyte-retrievals per year:711±636,range100–2200; cycles with cleavage-stage embryo-transfer:322±339,0–1300; cycles with blastocyst-stage embryo-transfer:390±403,0–1100; operators per center:5.6±4.0,2–13; senior embryologists’ experience:14.8±7.4yr,7–30; junior embryologists’ experience:2.7±0.6yr,1–3. The intra-center concordance was (i)for blastomeres’ symmetry 82±15% (38–100%), k 0.59±0.27 (0.02–1), (ii)for blastomeres’ fragmentation 88±9% (65–100%), k 0.71±0.2 (0.29–1), (iii)for blastocysts’ expansion 80±16% (48–100%), k 0.66±0.27 (0.19–1), (iv)for inner-cell-mass quality 73±16% (35–95%), k 0.58±0.24 (0.07–0.92), (v)for trophectoderm quality 71±19% (38–95%), k 0.54±0.32 (0.01–0.97). Linear regressions showed no association of centers’ and embryologists’ characteristics with all k-values.

Among clinics with the highest mean number of cycles per year and intra-center concordance, we selected 6 experts for the interactive-training. We then calculated the inter-center concordance as the agreement rate between senior embryologists and the experts for phase-I and phase-III: (i)for blastomeres’ symmetry 67±15% (30–85%) and 73±17% (15–90%;Wilcoxon-signed-ranks-test=0.06), k 0.33±0.22 (–0.29–0.58) and 0.42±0.33 (–0.56–0.77); (ii)for blastomeres’ fragmentation 81±17% (23–95%) and 83±14% (50–95%;Wilcoxon-signed-ranks-test=0.8), k 0.54±0.22 (–0.05–0.84) and 0.55±0.22 (0.17–0.81); (iii)for blastocysts’ expansion 59±16% (35–85%) and 67±17% (23–90%;Wilcoxon-signed-ranks-test=0.04), k 0.35±0.20 (0.06–0.73) and 0.44±0.22 (–0.10–0.7); (iv)for inner-cell-mass quality 60±14% (33–80%) and 69±11% (48–85%;Wilcoxon-signed-ranks-test=0.02), k 0.40±0.20 (0.01–0.69) and 0.51±0.18 (0.18–0.77); (v)for trophectoderm quality 55±12% (23–70%) and 63±10% 48–78%;Wilcoxon-signed-ranks-test<0.01), k 0.29±0.15 (–0.08–0.52) and 0.42±0.15 (0.21–0.66).

Limitations, reasons for caution

Only 28% (N = 18/65) of the Italian IVF centers invited to participate responded to the survey. The conventional adoption of grading schemes other than Istanbul-Consensus by 50% of the embryologists might have biased their evaluation. The experts were not fully-concordant in grading 13.8% of the embryos (N = 22/160), which required active discussions.

Wider implications of the findings: Blastocyst-grading concordance was significantly improved after the training phase. Therefore, interactive consensus meetings and training platforms are keenly needed to standardize this practice across the centers. The “avant-garde” of artificial intelligence applied to embryo image analysis might help overcoming this issue in the future.

Trial registration number

N.A.

P–606 A second stimulation in the same ovarian cycle rescues advanced-maternal-age patients obtaining ≤ 3 blastocysts after the conventional approach by preventing treatment-discontinuation

Study question

Is double stimulation in the same ovarian cycle (DuoStim) a valuable strategy to rescue advanced-maternal-age patients obtaining ≤ 3 blastocysts for chromosomal-testing after conventional stimulation?

Summary answer

DuoStim is effective to prevent treatment discontinuation thereby increasing the 1-year cumulative-live-birth-rate among advanced-maternal-age patients obtaining 0–3 blastocysts after a first conventional stimulation.

What is known already

Folliculogenesis is characterized by continuous waves of follicular growth. DuoStim approach exploits these dynamics to conduct two stimulations in a single ovarian cycle and improve the prognosis of advanced-maternal-age and/or reduced-ovarian-reserve women. Independent groups worldwide successfully adopted DuoStim with various regimens reporting similar oocyte/embryo competence after both stimulations. Recently, we have demonstrated the fruitful adoption of DuoStim in patients fulfilling the Bologna criteria, especially because of the prevention of treatment discontinuation. Here we aimed at investigating whether DuoStim can be adopted to rescue poor prognosis patients obtaining 0–3 blastocysts after the conventional approach.

Study design, size, duration

Proof-of-concept matched case-control study. All patients obtaining 0–3 blastocysts after conventional-stimulation between 2015–2018 were proposed DuoStim. The 143 couples who accepted were matched for maternal age, sperm factor, cumulus-oocyte-complexes and blastocysts obtained after the first stimulation to 143 couples who did not. The primary outcome was the 1-year cumulative-live-birth-rate. If not delivering, the control group had 1 year to undergo a second attempt with conventional-stimulation. All treatments were concluded (live-birth achieved or no euploid left).

Participants/materials, setting, methods

Only GnRH-antagonist with recombinant-gonadotrophins and agonist trigger stimulation protocols were adopted. All cycles entailed ICSI with ejaculated sperm, blastocyst culture, trophectoderm biopsy, comprehensive-chromosome-testing and vitrified-warmed euploid single-embryo-transfer(s). Cumulative-live-birth-rate was calculated per patient considering both stimulations in the same ovarian cycle (DuoStim group) or up to two stimulations in 1 year (control group). Treatment discontinuation rate in the control group was calculated as patients who did not return for a second stimulation among non-pregnant ones.

Main results and the role of chance

Among the 286 couples included (41.0±2.9yr;4.9±3.1 cumulus-oocytes-complexes and 0.8±0.9 blastocysts), 126 (63 per group), 98 (49 per group), 52 (26 per group) and 10 (5 per group) obtained 0,1,2 and 3 blastocysts after the first stimulation, respectively. The cumulative-live-birth-rate was 9% in the control group after the first attempt (N = 13/143). Among the 130 non-pregnant patients, only 12 returned within 1-year (165±95days later;discontinuation rate=118/130,91%), and 3 delivered. Thus, the cumulative-live-birth-rate from two stimulations in 1-year was 11% (N = 16/143). In the DuoStim group, the cumulative-live-birth-rate was 24% (N = 35/143; Fisher’s-exact-test< 0.01,power=80%). The odds-ratio of delivering in the DuoStim versus the control group adjusted for all matching criteria was 3.3,95%CI:1.6–7.0,p<0.01. This difference (0%,22%,15% and 20% in the control versus 10%,31%,46% and 40% in the DuoStim group among patients obtaining 0,1,2 and 3 blastocysts at the first stimulation, respectively) is mainly due to treatment discontinuation in the control group (98%,65%,77% and 80% among patients obtaining 0,1,2 and 3 blastocysts at the first stimulation, respectively) and the further increased maternal age at the time of second retrieval (∼6 months). Notably, 2 patients delivered 2 live-births after DuoStim (none in the control) and 14 patients with a live-birth have euploid blastocysts left (2 in the control).

Limitations, reasons for caution

Randomized-controlled-trials and cost-effectiveness analyses are desirable to confirm these data. Moreover, 75% of the patients included were >39yr and 44% obtained no blastocyst after the first stimulation. Therefore future studies among younger women and/or more women obtaining ≥1 blastocyst are advisable to set reasonable cut-off values to apply this strategy.

Wider implications of the findings: A second stimulation in the same ovarian cycle might be envisioned as a rescue strategy for poor IVF outcomes after a first stimulation, so to prevent treatment discontinuation and increase the cumulative-live-birth-rate. This is feasible since 6–7 days span the first and the second stimulation in the DuoStim protocol.

Trial registration number

none

P–210 Abnormal cleavage patterns during embryo preimplantation development and their effect on blastulation: an overview from IVF patients with multiple IVF cycles in a time-lapse incubator

Study question

How common abnormal cleavage patterns (ACP) are in IVF and what are their consequences on embryo developmental competence?

Summary answer

ACP might affect up to 25% of the 2PN-zygotes, independently from patients’/cycles’ characteristics, and mostly cause embryo developmental arrest around the 4-to–8-cell transition.

What is known already

Since its implementation in IVF, time-lapse-microscopy (TLM) allowed the standardization of embryo culture within undisturbed incubators, but it has not improved embryo selection especially if blastocyst transfer is performed. Nevertheless, TLM holds the potential for boosting our knowledge of embryo preimplantation development. In particular, a continuous observation of embryo morpho-dynamics unveiled peculiar blastomere cleavage patterns previously unidentifiable with a static morphological assessment. These events are possibly associated with massive mitotic errors, affecting both chromosomes and cytoskeletal components, as well as downstream metabolic imbalances. Still, the causes of ACP and their consequences on embryo developmental/reproductive competence require further investigation.

Study design, size, duration

Observational study including 75 patients (age:38.6±3.7yr, FSH:8.8±3.6IU/l, AMH:1.7±1.3ng/ml; BMI:21.4±2.4) who conducted multiple IVF cycles (N = 160; 8.7±5.0 cumulus-oocyte-complexes and 6.3±3.6 metaphase-II collected; 201±245 days between first and second cycles) in a time-lapse incubator between 2014–2020. All annotations were performed blindly by two operators and confirmed by a third in case of discordance. The outcomes were the blastulation rate after any ACP, their association between each other and with patients’/cycles’ characteristics.

Participants/materials, setting, methods

We included only ICSI-cycles after ovarian-stimulation with blastocyst culture conducted in the Embryoscope. Overall, 981 metaphase-II were inseminated and 677 2PN-zygotes annotated. The ACP investigated were: (i)cytokinesis-failure, formation of cytoplasmic septa without cell division; (ii)Chaotic-cleavage, disordered and uneven cleavages; (iii)Direct-unequal-cleavage (DUC), cleavage of zygotes or single blastomeres directly into 3; (iv)Rapid-cleavage, t3-t2<5hr; (v)Reverse-cleavage, fusion of 2 blastomeres into 1; (vi)Fragmentation, presence of numerous non-nucleated fragments; (vii)Blastomeres’ exclusion/extrusion, nucleated cells excluded/extruded from the morula.

Main results and the role of chance

Among the 2PN-zygotes, the prevalence of cytokinesis-failure was 5.9% (N = 40/677), 15.7% for chaotic-cleavage (N = 106/677), 18.6% for DUC (N = 126/677), 4.1% for rapid-cleavage (N = 28/677), 3.5% for reverse-cleavage (N = 24/677) and 24.1% for fragmentation (N = 163/677). Among the morulae, the prevalence of blastomere exclusion/extrusion was 27% (N = 109/410;1.5±1.2 excluded/extruded cells,range:1–7). The risk for reverse-cleavage was higher among 2PN-zygotes facing failed-cytokinesis (N = 8/40,20% versus N = 16/637,2.5%, OR:9.7,95%CI:3.9–24.3,p<0.01). Fragmentation was instead higher among 2PN-zygotes undergoing chaotic cleavage (N = 47/106,44.3% versus N = 116/571,20.3%, OR:3.1,95%CI:2–4.8,p<0.01) or DUC (N = 46/126,36.5% versus N = 117/551,21.2%, OR:2.1,95%CI:1.4–3.2,p<0.01). Lastly, higher prevalence of blastomeres’ exclusion/extrusion were reported among morulae obtained after chaotic-cleavage (N = 17/29,58.6% versus N = 92/381,24.1%, OR:4.4,95%CI:2–9.7,p<0.01), DUC (N = 26/37,70.3% versus N = 83/373,22.3%, OR:8.3,95%CI:3.9–17.4,p<0.01) and in presence of fragmentation (N = 79/195,75.2% versus N = 30/305,9.8%, OR:27.8,95%CI:15.6–49.8,p<0.01); only a higher trend after rapid-/reverse-cleavage.

No predictive factor of ACP was identified among patients’ and cycles’ characteristics, except for higher risks of fragmentation (OR:2.6,95%CI:1.1–6.3,p= 0.04) and blastomeres’ exclusion/extrusion (OR:2.7,95%CI:1.1–7.2,p=0.04) among patients with previous experience with these events.

The viable-blastocyst rate per 2PN-zygote was 45.1% (N = 305/677). It was lower in case of failed-cytokinesis (N = 12/40,30% versus N = 293/637,46%, OR:0.5,95%CI:0.25–0.99,p=0.05), chaotic cleavage (N = 20/106,18.9% versus N = 285/571,49.9%, OR:0.23,95%CI:0.14–0.39,p<0.01), DUC (N = 27/126,21.4% versus N = 278/551,50.5%, OR:0.27,95%CI:0.17–0.42,p<0.01), rapid-cleavage (N = 6/22,21.4% versus N = 299/649,46.1%, OR:0.32,95%CI:0.13–0.8,p=0.02), and reverse-cleavage (N = 5/19,20.8% versus N = 300/653,45.9%, OR:0.31, 95%CI:0.11–0.84,p=0.02). No difference was instead shown in case of fragmentation and/or blastomeres’ exclusion/extrusion.

Limitations, reasons for caution

The patients included were poor-prognosis women undergoing ≥2 cycles. We are expanding the sample size to account for all cycles conducted in time-lapse incubators. Larger sample size will provide also statistical-power to investigate the effect of ACP on blastocysts’ chromosomal and implantation competence, and more visualizations of rapid-/reverse-cleavage events.

Wider implications of the findings: After ACP,developmental-arrest mostly occurs around the 4-to–8-cell transition (50–70% versus ∼30%), when embryonic-genome-activation takes place. Surviving embryos often fragment and/or exclude/extrude blastomeres at morulation, without further impact on blastulation-rates. Moreover, ACP seem independent from patients’/cycles’ characteristics. These evidence incite future Research on the biological/genetic mechanisms triggering ACP and their consequences.

Trial registration number

None

P–519 Investigation of embryo chromosomal constitution and live birth rate after vitrified-warmed euploid single blastocyst transfer across ranges of maternal body-mass-index

Study question

Does maternal body-mass-index (BMI) associate with blastocysts’ chromosomal constitution and clinical outcomes in infertile patients undergoing preimplantation genetic testing for aneuploidies (PGT-A)?

Summary answer

A higher euploidy rate per biopsied blastocyst was reported among underweight women. Overweight women were instead subject to higher miscarriage (MR) and lower live-birth-rates (LBR).

What is known already

Different studies in the literature revealed an association between BMI and infertility, suggesting a J-shaped relationship: both underweight and overweight women can suffer from infertility issues. Even if IVF might increase the success rate in both these categories of patients, it seems insufficient per se to overcome the complex and multifactorial fertility impairment derived from unbalanced nutritional intakes. Miscarriage, in particular, is common in both underweight and overweight women. However, most of the literature is based on chromosomally-untested embryos. Study design, size, duration: Retrospective observational study. Only the first IVF cycle with ≥1 biopsied blastocyst from each woman was included. The primary outcome was the association between maternal BMI (underweight, BMI<18.5, n = 160; normal-weight, BMI=18–25, N = 1392; overweight, BMI>25, N = 259) and the mean euploidy rate per cohort of biopsied blastocysts (m-ER). The secondary outcomes were the association between maternal BMI with clinical (mainly MR and LBR), gestational and perinatal outcomes after first vitrified-warmed single euploid blastocyst transfers.

Participants/materials, setting, methods

We included 1811 women undergoing PGT-A at a private IVF center between April–2013 and March–2020. The secondary outcomes were investigated on 1125 first vitrified-warmed single euploid blastocyst transfers from all patients obtaining ≥1 transferable blastocyst. Only ICSI with ejaculated sperm and continuous culture in standard incubators were performed. Logistic regressions were conducted to identify putative confounders and adjust the results accordingly.

Main results and the role of chance

Except for a lower maternal age among underweight women (38.3±3.1 versus 38.9±3.4 yr, p < 0.01) and higher among overweight ones (39.3±3.6 yr, p = 0.04), no difference was reported with respect to normal-weight women in terms of duration of infertility, hormonal levels, main cause of infertility, sperm quality, and reproductive history. The mean number of biopsied blastocysts was ∼3 in all groups. The m-ER shows a decreasing trend as the maternal BMI increases between 17 and 22–23, to then plateau. In fact, a significant difference was reported between underweight (50.8%±36.4%) and normal-weight women (41.4%±37.5%, p < 0.01). A linear regression adjusted for maternal age confirmed this moderate association between increasing BMI and m-ER (unstandardized-coefficient-B –0.6%, 95%CI:–1.1% to –0.1%, p = 0.02).

Morphological quality and day of full-blastulation among transferred euploid blastocysts was similar in the three groups. Overweight women showed higher MR per pregnancy (N = 20/75, 26.7%, 95%CI:17.4%–38.3% versus N = 67/461, 14.5%, 95%CI:11.5%–18.2%; OR 2.0, 95%CI:1.1–3.6, p = 0.01) and lower LBR per transfer (N = 55/154, 35.7%, 95%CI:28.3%–43.8% versus N = 388/859, 45.2%, 95%CI:41.8%–48.6%; OR adjusted for euploid blastocysts’ features 0.67, 95%CI:0.46–0.96, p = 0.03). Clinical outcomes were instead similar among underweight and normal-weight women. All gestational and perinatal outcomes were comparable in the tree groups.

Limitations, reasons for caution

Our study is limited by its retrospective nature, and the fact that maternal BMI was measured only before oocyte retrieval and not before embryo transfer. Moreover, the reduced sample size did not allow for further relevant sub-analyses among solely obese women.

Wider implications of the findings: When possible nutritional/lifestyle modifications should be encouraged to adjust maternal BMI before IVF. Overweight patients should be especially informed of their higher risk for miscarriage. Yet, BMI is just a gross marker, future studies based on body fat localization and percentage (e.g. by bioelectrical impedance analyses) are desirable.

Trial registration number

None

Measurement of leukocyte trafficking kinetics in macaques by serial intravascular staining

Leukocyte trafficking enables detection of pathogens, immune responses, and immune memory. Dysregulation of leukocyte trafficking is often found in disease, highlighting its important role in homeostasis and the immune response. Whereas some of the molecular mechanisms mediating leukocyte trafficking are understood, little is known about the regulation of trafficking, including trafficking kinetics and its impact on immune homeostasis. We developed a method of serial intravascular staining (SIVS) to measure trafficking kinetics in nonhuman primates using infusions of fluorescently labeled antibodies to label circulating leukocytes. Because antibody infusions labeled only leukocytes in the blood, cells were "barcoded" according to their location at the time of each infusion, providing positional histories that could be used to infer trafficking kinetics. We used SIVS and multiparameter flow cytometry to quantitate cellular trafficking into lymphoid tissues of healthy animals at homeostasis and to identify perivascular cells that could be unique to nonlymphoid organs. To investigate how these parameters could be influenced during disease, SIVS was used to quantify lymphocyte trafficking in macaques infected with the bacterial pathogen Mycobacterium tuberculosis and to enumerate intravascular leukocytes in lung granulomas. We showed that whereas most cells in lung granulomas were localized there for more than 24 hours, granulomas were dynamic with a slow continual cellular influx, the rate of which predicted clearance of M. tuberculosis from the granulomas. SIVS, in combination with intracellular staining and multiparametric flow cytometry, is a powerful method to quantify the kinetics of leukocyte trafficking in nonhuman primates in vivo.

Immunogenicity of Protein Therapeutics: A Lymph Node Perspective

The continuous development of molecular biology and protein engineering technologies enables the expansion of the breadth and complexity of protein therapeutics for in vivo administration. However, the immunogenicity and associated in vivo development of antibodies against therapeutics are a major restriction factor for their usage. The B cell follicular and particularly germinal center areas in secondary lymphoid organs are the anatomical sites where the development of antibody responses against pathogens and immunogens takes place. A growing body of data has revealed the importance of the orchestrated function of highly differentiated adaptive immunity cells, including follicular helper CD4 T cells and germinal center B cells, for the optimal generation of these antibody responses. Understanding the cellular and molecular mechanisms mediating the antibody responses against therapeutics could lead to novel strategies to reduce their immunogenicity and increase their efficacy.

Comprehensive Flow Cytometry Analysis of PEI-Based Transfections for Virus-Like Particle Production

The generation of stable clones for biomolecule production is a common but lengthy and labor-intensive process. For complex molecules, such as viruses or virus-like particles (VLPs), the timeline becomes even more cumbersome. Thus, in the early stages of development, transient production methods serve as a reasonable alternative to stable clone construction. In this work, an investigation of a polyethylenimine- (PEI-) based transfection method for the transient production of Chikungunya (Chik) VLPs, a vaccine candidate molecule, was undertaken. This effort focuses on tracking cell population responses during transfection, understanding how process changes affect these responses, and monitoring patterns in cell performance over the culture duration. Plasmid labeling and VLP staining were employed to comprehensively track cells via flow cytometry and to draw correlations between plasmid DNA (pDNA) uptake and the resulting VLP expression. The method detected high transfection efficiency (≥97%) in all samples tested and demonstrated the capability to track kinetics of plasmid-cell binding. With varied transfection cell concentrations, the pDNA binding kinetics are altered and saturation binding is observed in the lowest cell concentration sample tested in less than 3 hours of incubation. Interestingly, in all samples, the flow cytometry analysis of relative pDNA amount versus VLP expression staining showed that cells which contained fewer pDNA complexes resulted in the highest levels of VLP stain. Finally, to determine the potential breadth of our observations, we compared daily expression patterns of ChikVLP with a reporter, monomeric GFP molecule. The similarities detected suggest the interpretations presented here to likely be more broadly informative and applicable to PEI-based transient production of additional biological products as well.

Bispecific antibodies: Potential immunotherapies for HIV treatment

Bispecific (bs) antibodies (Abs, bsAbs) are engineered immunoglobulins that contain two different antigen-binding sites in one molecule. bsAbs can be divided in two molecular formats; the IgG-like and non-IgG like. The structural elements of each format have implications for engaging the immune system. Elimination of HIV will need sophisticated approaches with immunotherapies being one of the strategies under investigation. Furthermore, HIV genetic variability and functional compromise of the adaptive CTL response complicate the potential usefulness of some immunotherapeutic strategies. Inclusion of novel HIV neutralizing Abs with high potency and breadth as components of bsAbs could represent alternative strategies for virus elimination by harnessing the adaptive immune response in vivo.

Developmental regulation of type 1 and type 3 interferon production and risk for infant infections and asthma development

BACKGROUND

Virus-associated febrile lower respiratory tract infections (fLRIs) during infancy have been identified as risk factors for persistent wheeze development. We hypothesized that variations in innate immune defense capacity during this period, as exemplified by production of type 1 and 3 interferons (T1/3IFNs), might be an underlying determinant of risk.

OBJECTIVE

We sought to investigate relationships between postnatal development of innate interferon response capacity and susceptibility to early infections and persistent wheeze.

METHODS

We studied a subset of subjects from a birth cohort at high risk for asthma/allergy and determined the capacity of cord blood cells (n = 151) to produce any of a panel of 17 T1/3IFNs in response to the viral mimic polyinosinic-polycytidylic acid using a sensitive PCR assay. We investigated relationships between neonatal interferon responses and lower respiratory tract infection history during infancy, wheezing history to 5 age years, and ensuing maturation of innate immune capacity by age 4 years (n = 160) and 10 years (n = 125).

RESULTS

Although cohort subjects produced an average of 2.6 ± 0.3 of the 17 innate interferons tested at birth, 24% showed no T1/3IFN production. This nonproducer subgroup showed increased risk for infant fLRIs (odds ratio, 2.62; 95% CI, 1.14-6.06; P = .024) and persistent wheeze (odds ratio, 4.24; 95% CI, 1.60-11.24; P = .004) at age 5 years relative to those producing 1 or more T1/3IFNs, whereas risk for infant wheezy lower respiratory tract infections or "transient early wheeze" was unaffected. Moreover, infants who experienced fLRIs subsequently demonstrated accelerated development of T1/3IFN response capacity between 1 and 4 years of age.

CONCLUSIONS

T1/3IFN response capacity appears strongly developmentally constrained at birth. Infants in whom this negative regulation is strongest manifest increased risk for severe respiratory tract infections during infancy and subsequent persistent wheeze.

BACH2 regulates CD8(+) T cell differentiation by controlling access of AP-1 factors to enhancers

T cell antigen receptor (TCR) signaling drives distinct responses depending upon the differentiation state and context of CD8⁺ T cells. We hypothesized that access of signal-dependent transcription factors (TFs) to enhancers is dynamically regulated to shape transcriptional responses to TCR signaling. We found that the TF BACH2 restrains terminal differentiation to enable generation of long-lived memory cells and protective immunity following viral infection. BACH2 was recruited to enhancers where it limited expression of TCR-driven genes by attenuating the availability of activator protein 1 (AP-1) sites to Jun family signal-dependent TFs. In naïve cells, this prevented TCR-driven induction of genes associated with terminal differentiation. Upon effector differentiation, reduced expression of BACH2 and its phosphorylation enabled unrestrained induction of TCR-driven effector programs.

High-throughput quantitative real-time RT-PCR assay for determining expression profiles of types I and III interferon subtypes

Described in this report is a qRT-PCR assay for the analysis of seventeen human IFN subtypes in a 384-well plate format that incorporates highly specific locked nucleic acid (LNA) and molecular beacon (MB) probes, transcript standards, automated multichannel pipetting, and plate drying. Determining expression among the type I interferons (IFN), especially the twelve IFN-α subtypes, is limited by their shared sequence identity; likewise, the sequences of the type III IFN, especially IFN-λ2 and -λ3, are highly similar. This assay provides a reliable, reproducible, and relatively inexpensive means to analyze the expression of the seventeen interferon subtype transcripts.

A new approach for monitoring ebolavirus in wild great apes

BACKGROUND

Central Africa is a "hotspot" for emerging infectious diseases (EIDs) of global and local importance, and a current outbreak of ebolavirus is affecting multiple countries simultaneously. Ebolavirus is suspected to have caused recent declines in resident great apes. While ebolavirus vaccines have been proposed as an intervention to protect apes, their effectiveness would be improved if we could diagnostically confirm Ebola virus disease (EVD) as the cause of die-offs, establish ebolavirus geographical distribution, identify immunologically naïve populations, and determine whether apes survive virus exposure.

METHODOLOGY/PRINCIPAL FINDINGS

Here we report the first successful noninvasive detection of antibodies against Ebola virus (EBOV) from wild ape feces. Using this method, we have been able to identify gorillas with antibodies to EBOV with an overall prevalence rate reaching 10% on average, demonstrating that EBOV exposure or infection is not uniformly lethal in this species. Furthermore, evidence of antibodies was identified in gorillas thought previously to be unexposed to EBOV (protected from exposure by rivers as topological barriers of transmission).

CONCLUSIONS/SIGNIFICANCE

Our new approach will contribute to a strategy to protect apes from future EBOV infections by early detection of increased incidence of exposure, by identifying immunologically naïve at-risk populations as potential targets for vaccination, and by providing a means to track vaccine efficacy if such intervention is deemed appropriate. Finally, since human EVD is linked to contact with infected wildlife carcasses, efforts aimed at identifying great ape outbreaks could have a profound impact on public health in local communities, where EBOV causes case-fatality rates of up to 88%.

Ankle fracture: radiographic approach according to the Lauge-Hansen classification

Ankle fractures account for 9 % of fractures (Clare in Foot Ankle Clin 13(4):593-610, 1) representing a significant portion of the trauma workload; proximal femoral fractures are the only lower limb fracture to present more frequently. Ankle fractures have a bimodal age distribution with peaks in younger males and older females (Arimoto and Forrester in AJR Am J Roentgenol 135(5):1057-1063, 2). There has been threefold increase in the incidence among elderly females over the past three decades (Haraguchi and Armiger in J Bone Joint Surg Am 91(4):821-829, 3). In 1950, Lauge-Hansen devised a classification of ankle fractures based on the position of the foot and the deforming force at the time of injury. This has been widely accepted by orthopedists, but is not in general use by radiologists. Identification of the fractures and classification of the type of injury allows diagnosis of the otherwise occult ligamentous injuries. Three radiographic views of the ankle (anteroposterior, mortise, and lateral) are necessary to classify an injury with the Lauge-Hansen system. Two additional criteria are also necessary: the position of the foot at the time of injury and the direction of the deforming force.

Adult-onset pulmonary involvement in Niemann-Pick disease type B

Niemann-Pick disease type B is caused by a deficiency in acid sphingomyelinase activity; among the six variants of Niemann-Pick disease known to date, it is the most frequently associated with lung involvement, a major cause of morbidity and mortality in this subtype in patients of all ages. Nevertheless, the vast majority of reports in the literature concern infantile forms, while less reported is, for several reasons, the onset in adults being consequently still poorly understood and characterized its clinical, radiographic and functional manifestations. We report a case of a 37 years-old female patient affected by subtype B since she was an infant, operated for aortic valve replacement two years before and came to our attention for the onset of a worsening exertional dyspnoea which proved, through a series of functional tests and radiological exams, to be a consequence of the diffuse lung involvement by the metabolic disorder; we performed a review on this topic through a Medline search of all the available "adult-onset" case reports published since the first description in 1964, also considering the possible association between NPDB and, more generally lysosomal storage disorders, and the valvular disease, already suggested by several Authors in previous works.

Demonstration of cross-protective vaccine immunity against an emerging pathogenic Ebolavirus Species

A major challenge in developing vaccines for emerging pathogens is their continued evolution and ability to escape human immunity. Therefore, an important goal of vaccine research is to advance vaccine candidates with sufficient breadth to respond to new outbreaks of previously undetected viruses. Ebolavirus (EBOV) vaccines have demonstrated protection against EBOV infection in nonhuman primates (NHP) and show promise in human clinical trials but immune protection occurs only with vaccines whose antigens are matched to the infectious challenge species. A 2007 hemorrhagic fever outbreak in Uganda demonstrated the existence of a new EBOV species, Bundibugyo (BEBOV), that differed from viruses covered by current vaccine candidates by up to 43% in genome sequence. To address the question of whether cross-protective immunity can be generated against this novel species, cynomolgus macaques were immunized with DNA/rAd5 vaccines expressing ZEBOV and SEBOV glycoprotein (GP) prior to lethal challenge with BEBOV. Vaccinated subjects developed robust, antigen-specific humoral and cellular immune responses against the GP from ZEBOV as well as cellular immunity against BEBOV GP, and immunized macaques were uniformly protected against lethal challenge with BEBOV. This report provides the first demonstration of vaccine-induced protective immunity against challenge with a heterologous EBOV species, and shows that Ebola vaccines capable of eliciting potent cellular immunity may provide the best strategy for eliciting cross-protection against newly emerging heterologous EBOV species.

Ebola virus causes death, fear, and economic disruption during outbreaks. It is a concern worldwide as a natural pathogen and a bioterrorism agent, and has caused death to residents and tourists of Africa where the virus circulates. A vaccine strategy to protect against all circulating Ebola viruses is complicated by the fact that there are five different virus species, and individual vaccines provide protection only against those included in the vaccine. Making broad vaccines that contain multiple components is complicated, expensive, and poses challenges for regulatory approval. Therefore, in the present work, we examined whether a prime-boost immunization strategy with a vaccine targeted to one Ebola virus species could cross protect against a different species. We found that genetic immunization with vectors expressing the Ebola virus glycoprotein from Zaire blocked infection with a newly emerged virus species, Bundibugyo EBOV, not represented in the vaccine. Protection occurred in the absence of antibodies against the second species and was mediated instead by cellular immune responses. Therefore, single-component vaccines may be improved to protect against multiple Ebola viruses if they are designed to generate this type of immunity.

Vertebroplasty as a Treatment for Primary Benign or Metastatic Cervical Spine Lesions: Up to One Year of Follow-up

This paper illustrates the validity of vertebroplasty (VP) in patients with primary benign or metastatic lesion in the cervical spine. From January 2006 to December 2007, ten consecutive patients were treated with VP for a total of ten vertebral bodies: two symptomatic vertebral haemangiomas at C5 and C4.3, multiple myeloma at C2 (two cases) and one case at C4, five patients with vertebral metastasis from breast or lung cancer at C2, C4 (three cases) and C5. All the patients complained of pain resistant to continuous medical management. All procedures were performed under general anaesthesia by anterolateral approach under CT or fluoroscopy control with manual dislocation of the carotid axis. A transoral approach under fluoroscopy was performed to treat the C2 lesion. Bone biopsy was never performed. VP was performed to prevent fracture after implantation of a double discal prothesis in two patients. For patients with multiple myeloma, VP was performed to prevent new vertebral fracture. VP was performed before of radiotherapy in three patients with metastasis, and just after radiotherapy in two. Two metastatic patients were lost at one year follow-up due to death from systematic diffusion. Results were evaluated on the Visual Analogue Scale (VAS) and the Oswestry Disability Index (ODS). A successful outcome was observed with a complete resolution or partial reduction of pain in 90% of patients 24-72 hours after VP. At 12 months follow-up, we recorded a reduction of four points in the VAS evaluation and a 45% reduction in the ODS score. No extravertebral vascular or discal cement leakage was observed. At 12 months, X-ray follow-up showed a stable result. Percutaneous treatment with VP for benign or malignant cervical spine lesions is a valuable, mini-invasive and quick method that allows a complete and enduring resolution of painful vertebral symptoms without fracture of the adjacent or distal vertebral bodies.

Truncated hemoglobin GlbO from Mycobacterium leprae alleviates nitric oxide toxicity

As a consequence of reductive genome evolution, the obligate intracellular pathogen Mycobacterium leprae has minimized the repertoire of genes implicated in defense against reactive oxygen and nitrogen species. Genes for multiple hemoglobin types coexist in mycobacterial genomes, but M. leprae has retained only glbO, encoding a group-II truncated hemoglobin. Mycobacterium tuberculosis GlbO has been involved in oxygen transfer and respiration during hypoxia, but a role in protection from nitric oxide (NO) has not been documented yet. Here, we report that the in vitro reaction of oxygenated recombinant M. leprae GlbO with NO results in an immediate stoichiometric formation of nitrate, concomitant with heme-protein oxidation. Overexpression of GlbO alleviates the growth inhibition of Escherichia colihmp (flavohemoglobin gene) mutants in the presence of NO-donors, partly complementing the defect in Hmp synthesis. A promoter element upstream of glbO was predicted in silico, and confirmed by using a glbO::lacZ transcriptional fusion in the heterologous Mycobacterium smegmatis system. The glbO::lacZ fusion was expressed through the whole growth cycle of M. smegmatis, and moderately induced by NO. We propose that M. leprae, by retaining the unique truncated hemoglobin GlbO, may have coupled O2 delivery to the terminal oxidase with a defensive mechanism to scavenge NO from respiratory enzymes. These activities would help to sustain the obligate aerobic metabolism required for intracellular survival of leprosy bacilli.

Nitric oxide scavenging by Mycobacterium leprae GlbO involves the formation of the ferric heme-bound peroxynitrite intermediate

Ferrous oxygenated (Fe(II)O2) hemoglobins (Hb's) and myoglobins (Mb's) have been shown to react very rapidly with NO, yielding NO3(-) and the ferric heme-protein derivative (Fe(III)), by means of the ferric heme-bound peroxynitrite intermediate (Fe(III)OONO), according to the minimum reaction scheme: Fe(II)O2 + NO (k(on))--> Fe(III)OONO (h)--> Fe(III) + NO3(-). For most Hb's and Mb's, the first step (indicated by k(on)) is rate limiting, the overall reaction following a bimolecular behavior. By contrast, the rate of isomerization and dissociation of Fe(III)OONO (indicated by h) is rate limiting in NO scavenging by Fe(II)O2 murine neuroglobin, thus the overall reaction follows a monomolecular behavior. Here, we report the characterization of the NO scavenging reaction by Fe(II)O2 truncated Hb GlbO from Mycobacterium leprae. Values of k(on) (=2.1x10(6) M(-1) s(-1)) and h (=3.4 s(-1)) for NO scavenging by Fe(II)O2 M. leprae GlbO have been determined at pH 7.3 and 20.0 degrees C, the rate of Fe(III)OONO decay (h) is rate limiting. The Fe(III)OONO intermediate has been characterized by optical absorption spectroscopy in the Soret region. These results have been analyzed in parallel with those of monomeric and tetrameric globins as well as of flavoHb and discussed with regard to the three-dimensional structure of mycobacterial truncated Hbs and their proposed role in protection from nitrosative stress.

S-palmitoylation modulates human estrogen receptor-α functions

17beta-Estradiol (E2)-induced rapid functions (from seconds to minutes) can be attributed to a fraction of nuclear estrogen receptor-alpha (ERalpha) localized at the plasma membrane. As a potential mechanism, we postulated that S-palmitoylation of the Cys447 residue may explain the ability of ERalpha to associate to plasma membrane making possible E2-dependent rapid functions [e.g., extracellular regulated kinase (ERK) activation]. Here, we report direct evidence that the mutation of the Cys447 residue to Ala impairs human ERalpha palmitoylation and E2-induced rapid ERK phosphorylation when transfected in ER-devoid HeLa cells. Moreover, the Cys447Ala mutation significantly decreases the E2-induced transactivation of an estrogen responsive element construct probe. Similar effects were obtained treating HeLa cells transfected with wild type ERalpha with the palmitoyl-acyltransferase inhibitor 2-bromo-hexadecanoic acid. Moreover, the deletion of the A-D domains (containing the DNA binding region) of ERalpha had no consequences on [(3)H]palmitate incorporation, whereas no palmitoylation occurred in the ERalpha mutant devoid of the E domain (i.e., ligand binding domain). These results point to the pivotal role of the Cys447 residue in ERalpha palmitoylation and in the modulation of E2-induced non-genomic functions.

Nitric oxide and Mycobacterium leprae pathogenicity

Leprosy is an old, still dreaded infectious disease caused by the obligate intracellular bacterium Mycobacterium leprae. During the infectious process, M. leprae is faced with the host macrophagic environment, where the oxidative stress and NO release, combined with low pH, low pO2, and high pCO2, contribute to limit the growth of the bacilli. Comparative genomics has unraveled massive gene decay in M. leprae, linking the strictly parasitic lifestyle with the reductive genome evolution. Compared with Mycobacterium tuberculosis and Mycobacterium bovis, the leprosy bacillus has lost most of the genes involved in the detoxification of reactive oxygen and nitrogen species. The very low reactivity of the unique truncated hemoglobin retained by M. leprae could account for the susceptibility of this exceptionally slow-growing microbe to NO.

Effect of acid adaptation on the fate of Listeria monocytogenes in THP-1 human macrophages activated by gamma interferon

In Listeria monocytogenes the acid tolerance response (ATR) takes place through a programmed molecular response which ensures cell survival under unfavorable conditions. Much evidence links ATR with virulence, but the molecular determinants involved in the reactivity to low pHs and the behavior of acid-exposed bacteria within host cells are still poorly understood. We have investigated the effect of acid adaptation on the fate of L. monocytogenes in human macrophages. Expression of genes encoding determinants for cell invasion and intracellular survival was tested for acid-exposed bacteria, and invasive behavior in the human myelomonocytic cell line THP-1 activated with gamma interferon was assessed. Functional approaches demonstrated that preexposure to an acidic pH enhances the survival of L. monocytogenes in activated human macrophages and that this effect is associated with an altered pattern of expression of genes involved in acid resistance and cell invasion. Significantly decreased transcription of the plcA gene, encoding a phospholipase C involved in vacuolar escape and cell-to-cell spread, was observed in acid-adapted bacteria. This effect was due to a reduction in the quantity of the bicistronic plcA-prfA transcript, concomitant with an increase in the level(s) of the monocistronic prfA mRNA(s). The transcriptional shift from distal to proximal prfA promoters resulted in equal levels of the prfA transcript (and, as a consequence, of the inlA, hly, and actA transcripts) under neutral and acidic conditions. In contrast, the sodC and gad genes, encoding a cytoplasmic superoxide dismutase and the glutamate-based acid resistance system, respectively, were positively regulated at a low pH. Morphological approaches confirmed the increased intracellular survival and growth of acid-adapted L. monocytogenes cells both in vacuoles and in the cytoplasm of interferon gamma-activated THP-1 macrophages. Our data indicate that preexposure to a low pH has a positive impact on subsequent challenge of L. monocytogenes with macrophagic cells.

The truncated hemoglobin from Mycobacterium leprae

Truncated hemoglobins (trHb's) form a family of low molecular weight O2 binding hemoproteins distributed in eubacteria, protozoa, and plants. TrHb's branch in a distinct clade within the hemoglobin (Hb) superfamily. A unique globin gene has recently been identified from the complete genome sequence of Mycobacterium leprae that is predicted to encode a trHb (M. leprae trHbO). Sequence comparison and modelling considerations indicate that monomeric M. leprae trHbO has structural features typical of trHb's, such as 20-40 fewer residues than conventional globin chains, Gly-based sequence consensus motifs, likely assembling into a 2-on-2 alpha-helical sandwich fold, and hydrophobic residues recognized to build up the protein matrix ligand diffusion tunnel. The ferrous heme iron atom of deoxygenated M. leprae trHbO appears to be hexacoordinated, like in Arabidopsis thaliana trHbO-3 (A. thaliana trHbO-3). Accordingly, the value of the second-order rate constant for M. leprae trHbO carbonylation (7.3 x 10(3) M(-1) s(-1)) is similar to that observed for A. thaliana trHbO-3 (1.4 x 10(4) M(-1) s(-1)) and turns out to be lower than that reported for carbon monoxide binding to pentacoordinated Mycobacterium tuberculosis trHbN (6.7 x 10(6) M(-1) s(-1)). The lower reactivity of M. leprae trHbO as compared to M. tuberculosis trHbN might be related to the higher susceptibility of the leprosy bacillus to toxic nitrogen and oxygen species produced by phagocytic cells.

Mu DNA reintegration upon excision: evidence for a possible involvement of nucleoid folding

Mutations induced by the integration of a Mugem2ts prophage can revert at frequencies around 1x10(-6). In these revertant clones, the prophage excised from its original localization is not lost but reintegrated elsewhere in the host genome. One of the most intriguing aspects of this process is that the prophage reintegration is not randomly distributed: there is a strong correlation between the original site of insertion (the donor site) and the target site of the phage DNA migration (the receptor site). In this paper, it is shown that in the excision-reintegration process mediated by Mugem2ts, the position of the initial prophage site strongly influences the location of the reintegration site. In addition, for each donor site, the receptor site is a discrete DNA region within which the excised Mu DNA can reintegrate and the two sites implicated in phage DNA migration must be located on the same DNA molecule. These data suggest the involvement of nucleoid folding in the excision-reintegration process.

Regulation of the bacteriophage Mu gem operon

The gem operon of bacteriophage Mu, responsible for the complex phenomenon of phage conversion, is included in the so called "semiessential early" region of phage DNA. Unlike the other early genes of the phage which are transcribed from the pe promoter, expression of the gem operon is driven by its own promoter, which escapes the control of the repressor. In fact, the transcript corresponding to gem was detected in immune lysogens by using a combined reverse transcription and a subsequent amplification of the resulting cDNA. The transcription initiation site from pgem was determined by primer extension mapping experiments and localized at 8217 bp from the left end of phage DNA. Two elements which could perform the negative control of gem were also identified. The first is a phage product, GemB, which presumably interferes with gem expression at a posttranscriptional level, whereas the second is a structural element, an inverted repeat immediately downstream of pgem, which acts as a terminator for the transcripts starting from pe. These transcripts could regulate gem expression by interfering with the initiation of transcription from pgem.

A spontaneous Escherichia coli K12 mutant which inhibits the excision-reintegration process of Mu gem2ts

Escherichia coli K12 strains lysogenic for Mu gem2ts with the prophage inserted in a target gene (i.e., lacZ::Mu gem2ts lysogenic strains) revert to Lac+ by prophage precise excision with a relatively high frequency (about 1 x 10(-6)). The revertants obtained are still lysogens with the prophage inserted elsewhere in the bacterial chromosome. We have observed that, with the time of storage in stabs, bacterial cultures lysogenic for Mu gem2ts lose the ability to excise the prophage. The mutation responsible for this effect was co-transducible with the gyrB gene. After the removal of the prophage by P1 vir transduction from these strains, one randomly chosen clone, R3538, was further analyzed. It shows an increment of DNA supercoiling of plasmid pAT153, used as a reporter, and a reduced beta-galactosidase activity. On the other hand, R3538 is totally permissive to both lytic and lysogenic cycles of bacteriophage Mu.

Reversal of Mu gem2ts-induced mutations

Mutations induced by the integration of a Mu gem2ts mutant prophage can revert at frequencies around 1 x 10(-6), more than 10(4)-fold higher than that obtained with Mu wild-type. Several aspects characterize Mu gem2ts precise excision: (i) the phage transposase is not involved; (ii) the RecA protein is not necessary; and (iii) revertants remain lysogenic with the prophage inserted elsewhere in the host genome. In addition, prophage re-integration seems to be non-randomly distributed, whereas Mu insertion into the host genome is a transposition event without any sequence specificity. In this paper, we describe that the site of re-integration somehow depends on the original site of insertion. Two alternative models are proposed to explain the strong correlation between donor and receptor sites.