A distinctive epigenetic ageing profile in human granulosa cells

STUDY QUESTION

Does women’s age affect the DNA methylation (DNAm) profile differently in mural granulosa cells (MGCs) from other somatic cells?

SUMMARY ANSWER

Accumulation of epimutations by age and a higher number of age-related differentially methylated regions (DMR) in MGCs were found compared to leukocytes from the same woman, suggesting that the MGCs have a distinctive epigenetic profile.

WHAT IS KNOWN ALREADY

The mechanisms underlying the decline in women’s fertility from the mid-30s remain to be fully elucidated. The DNAm age of many healthy tissues changes predictably with and follows chronological age, but DNAm age in some reproductive tissues has been shown to depart from chronological age (older: endometrium; younger: cumulus cells, spermatozoa).

STUDY DESIGN, SIZE, DURATION

This study is a multicenter cohort study based on retrospective analysis of prospectively collected data and material derived from healthy women undergoing IVF or ICSI treatment following ovarian stimulation with antagonist protocol. One hundred and nineteen women were included from September 2016 to June 2018 from four clinics in Denmark and Sweden.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Blood samples were obtained from 118 healthy women with varying ovarian reserve status. MGCs were collected from 63 of the 119 women by isolation from pooled follicles immediately after oocyte retrieval. DNA from leukocytes and MGCs was extracted and analysed with a genome-wide methylation array. Data from the methylation array were processed using the ENmix package. Subsequently, DNAm age was calculated using established and tailored age predictors and DMRs were analysed with the DMRcate package.

MAIN RESULTS AND ROLE OF CHANCE

Using established age predictors, DNAm age in MGCs was found to be considerable younger and constant (average: 2.7 years) compared to chronological age (average: 33.9 years). A Granulosa Cell clock able to predict the age of both MGCs (average: 32.4 years) and leukocytes (average: 38.8 years) was successfully developed. MGCs differed from leukocytes in having a higher number of epimutations (P = 0.003) but predicted telomere lengths unaffected by age (Pearson’s correlation coefficient = −0.1, P = 0.47). DMRs associated with age (age-DMRs) were identified in MGCs (n = 335) and in leukocytes (n = 1) with a significant enrichment in MGCs for genes involved in RNA processing (45 genes, P = 3.96 × 10−08) and gene expression (152 genes, P = 2.3 × 10−06). The top age-DMRs included the metastable epiallele VTRNA2-1, the DNAm regulator ZFP57 and the anti-Müllerian hormone (AMH) gene. The apparent discordance between different epigenetic measures of age in MGCs suggests that they reflect difference stages in the MGC life cycle.

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

No gene expression data were available to associate with the epigenetic findings. The MGCs are collected during ovarian stimulation, which may influence DNAm; however, no correlation between FSH dose and number of epimutations was found.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings underline that the somatic compartment of the follicle follows a different methylation trajectory with age than other somatic cells. The higher number of epimutations and age-DMRs in MGCs suggest that their function is affected by age.

STUDY FUNDING/COMPETING INTEREST(S)

This project is part of ReproUnion collaborative study, co-financed by the European Union, Interreg V ÖKS, the Danish National Research Foundation and the European Research Council. The authors declare no conflict of interest.

Natural killer T cell defects in multiple myeloma and the impact of lenalidomide therapy

The causes of multiple myeloma (MM) remain obscure and there are few known risk factors; however, natural killer T (NKT) cell abnormalities have been reported in patients with MM, and therapeutic targeting of NKT cells is promoted as a potential treatment. We characterized NKT cell defects in treated and untreated patients with MM and determined the impact of lenalidomide therapy on the NKT cell pool. Lenalidomide is an immunomodulatory drug with co-stimulatory effects on NKT cells in vitro and is an approved treatment for MM, although its mode of action in that context is not well defined. We find that patients with relapsed/progressive MM had a marked deficiency in NKT cell numbers. In contrast, newly diagnosed patients had relatively normal NKT cell frequency and function prior to treatment, although a specific NKT cell deficiency emerged after high-dose melphalan and autologous stem cell transplantation (ASCT) regimen. This also impacted NK cells and conventional T cells, but the recovery of NKT cells was considerably delayed, resulting in a prolonged, treatment-induced NKT cell deficit. Longitudinal analysis of individual patients revealed that lenalidomide therapy had no in-vivo impact on NKT cell numbers or cytokine production, either as induction therapy, or as maintenance therapy following ASCT, indicating that its clinical benefits in this setting are independent of NKT cell modulation.

Chylous leakage post mastectomy and axillary clearance: clinical aspect, causes and review of literature

Chylous leakage after mastectomy & axillary clearance is a rare complication. The incidence is less than 0.5%. Anatomical variations in the termination of thoracic duct can occur, rendering it susceptible to injury during axillary dissection. Most chyle leaks in the axilla are managed through conservative measures. Surgical intervention is required in high output chylous leaks. We encountered a case of chylous leak post mastectomy with axillary clearance, which was successfully treated conservatively.

Ex-vivo analysis of human natural killer T cells demonstrates heterogeneity between tissues and within established CD4(+) and CD4(-) subsets

Our understanding of human type 1 natural killer T (NKT) cells has been heavily dependent on studies of cells from peripheral blood. These have identified two functionally distinct subsets defined by expression of CD4, although it is widely believed that this underestimates the true number of subsets. Two recent studies supporting this view have provided more detail about diversity of the human NKT cells, but relied on analysis of NKT cells from human blood that had been expanded in vitro prior to analysis. In this study we extend those findings by assessing the heterogeneity of CD4(+) and CD4(-) human NKT cell subsets from peripheral blood, cord blood, thymus and spleen without prior expansion ex vivo, and identifying for the first time cytokines expressed by human NKT cells from spleen and thymus. Our comparative analysis reveals highly heterogeneous expression of surface antigens by CD4(+) and CD4(-) NKT cell subsets and identifies several antigens whose differential expression correlates with the cytokine response. Collectively, our findings reveal that the common classification of NKT cells into CD4(+) and CD4(-) subsets fails to reflect the diversity of this lineage, and that more studies are needed to establish the functional significance of the antigen expression patterns and tissue residency of human NKT cells.

Examining the adverse effects of limb position on pattern recognition based myoelectric control

Pattern recognition of myoelectric signals for the control of prosthetic devices has been widely reported and debated. A large portion of the literature focuses on offline classification accuracy of pre-recorded signals. Historically, however, there has been a semantic gap between research findings and a clinically viable implementation. Recently, renewed focus on prosthetics research has pushed the field to provide more clinically relevant outcomes. One way to work towards this goal is to examine the differences between research and clinical results. The constrained nature in which offline training and test data is often collected compared to the dynamic nature of prosthetic use is just one example. In this work, we demonstrate that variations in limb position after training can have a substantial impact on the robustness of myoelectric pattern recognition.

Testing the NKT cell hypothesis in lenalidomide-treated myelodysplastic syndrome patients

Myelodysplastic syndrome (MDS) comprises a group of clonal bone marrow disorders characterized by ineffective hematopoiesis and increased predisposition to acute myeloid leukemia. The causes of MDS remain poorly defined, but several studies have reported the NKT cell compartment of patients with MDS is deficient in number and functionally defective. In support of a central role for NKT cells, a pilot clinical study reported that lenalidomide (an approved treatment for MDS) increased NKT cell numbers in patients with MDS, and several in vitro studies showed lenalidomide specifically promoted NKT cell proliferation and cytokine production. We tested this in a much larger study and confirm a moderate in vitro augmentation of some NKT cell functions by lenalidomide, but find no impact on the NKT cell compartment of patients treated with lenalidomide, despite a consistently positive clinical response. We further show that the frequency and cytokine production of NKT cells is normal in patients with MDS before treatment and remains stable throughout 10 months of lenalidomide therapy. Collectively, our data challenge the concept that NKT cell defects contribute to the development of MDS, and show that a clinical response to lenalidomide is not dependent on modulation of NKT cell frequency or function.

Immune characterization of an individual with an exceptionally high natural killer T cell frequency and her immediate family

Natural killer T cells (NKT) are a regulatory subset of T lymphocytes whose frequency in peripheral blood is highly variable within the human population. Lower than normal NKT frequencies are associated with increased predisposition to a number of diseases, including type 1 diabetes and some forms of cancer, raising the possibility that an increased frequency may be protective. However, there is little or no understanding of how high NKT frequencies arise or, most importantly, whether the potential exists to boost and maintain NKT levels for therapeutic advantage. Here, we provide a detailed functional and phenotypic characterization of the NKT compartment of a human donor with NKT levels approximately 50 times greater than normal, including an analysis of NKT in her immediate family members. The study focuses upon the characteristics of this donor and her family, but demonstrates more broadly that the size and flexibility of the NKT niche is far greater than envisioned previously. This has important implications for understanding how the human NKT compartment is regulated, and supports the concept that the human NKT compartment might be expanded successfully for therapeutic benefit.

Emphysematous pyelonephritis in a diabetic patient with pelvic-ureteric stone

Emphysematous pyelonephritis is a rare but life threatening infection of kidney that is characterized by gas formation within or around the kidney. We describe a case of emphysematous pyelonephritis as a consequence of inadequately treated pelvic-ureteric stone in a diabetic man and complement this with a brief review of the literature pertaining in particular to the management of this condition.

Immune response in silico (IRIS): immune-specific genes identified from a compendium of microarray expression data

Immune cell-specific expression is one indication of the importance of a gene's role in the immune response. We have compiled a compendium of microarray expression data for virtually all human genes from six key immune cell types and their activated and differentiated states. Immune Response In Silico (IRIS) is a collection of genes that have been selected for specific expression in immune cells. The expression pattern of IRIS genes recapitulates the phylogeny of immune cells in terms of the lineages of their differentiation. Gene Ontology assignments for IRIS genes reveal significant involvement in inflammation and immunity. Genes encoding CD antigens, cytokines, integrins and many other gene families playing key roles in the immune response are highly represented. IRIS also includes proteins of unknown function and expressed sequence tags that may not represent genes. The predicted cellular localization of IRIS proteins is evenly distributed between cell surface and intracellular compartments, indicating that immune specificity is important at many points in the signaling pathways of the immune response. IRIS provides a resource for further investigation into the function of the immune system and immune diseases.

Subfascial endoscopic perforator vein surgery (SEPS) using the ultrasonic scalpel

Subfascial endoscopic perforator vein surgery (SEPS) was recently introduced as a minimally invasive method to ligate incompetent perforating veins in patients with severe chronic venous insufficiency of the lower extremities. Herein we describe a technique in which we used a 5-mm ultrasonic scalpel for the transection of perforating veins in 16 SEPS performed in 14 patients. The use of the ultrasonic scalpel allowed for the precise coagulation and transection of the perforator vein with hemostasis, while avoiding the use of metal clips. Our initial results showed that the technique was feasible with minimal morbidity. We recommend the use of the ultrasonic scalpel as an alternative tool to transect perforating veins in SEPS.

Inefficient ZAP-70 phosphorylation and decreased thymic selection in vivo result from inhibition of NF-kappaB/Rel

Signaling from the TCR regulates T lymphoid survival, deletion by apoptosis, and selective clonal expansion. One set of signaling pathways activated during thymic selection leads to degradation of a cytosolic retention protein, the inhibitor of kappaB (IkappaB)alpha, followed by nuclear translocation of the NF-kappaB/Rel family of transcription factors. It has been found previously that NF-kappaB proteins mediate a pathway signaling the survival of mature T cells and protection of thymocytes against TNF-induced apoptosis. In contrast, we show in this study that a transgenic inhibitor of NF-kappaB/Rel signaling interferes with the negative selection of immature thymocytes by endogenous MHC ligands in vivo. Positive selection of the H-Y TCR also was diminished. This attenuation of thymic selection efficiency was associated with decreased ZAP-70 phosphorylation and TCR signaling of CD69 induction. These findings demonstrate that the NF-kappaB transcriptional pathway plays an important role in normal processes of clonal deletion and they indicate that the NF-kappaB/IkappaB axis can regulate the efficiency of TCR signaling.

Unique signaling properties of B cell antigen receptor in mature and immature B cells: implications for tolerance and activation

Immature B cells display increased sensitivity to tolerance induction compared with their mature counterparts. The molecular mechanisms underlying these differences are poorly defined. In this study, we demonstrate unique maturation stage-dependent differences in B cell Ag receptor (BCR) signaling, including BCR-mediated calcium mobilization responses. Immature B cells display greater increases in intracellular calcium concentrations following Ag stimulation. This has consequences for the induction of biologically relevant responses: immature B cells require lower Ag concentrations for activation than mature B cells, as measured by induction of receptor editing and CD86 expression, respectively. BCR-induced tyrosine phosphorylation of CD79a, Lyn, B cell linker protein, and phospholipase Cgamma2 is enhanced in immature B cells and they exhibit greater capacitative calcium entry in response to Ag. Moreover, B cell linker protein, Bruton's tyrosine kinase, and phospholipase Cgamma2, which are crucial for the induction of calcium mobilization responses, are present at approximately 3-fold higher levels in immature B cells, potentially contributing to increased mobilization of calcium. Consistent with this possibility, we found that the previously reported lack of inositol-1,4,5-triphosphate production in immature B cells may be explained by enhanced inositol-1,4,5-triphosphate breakdown. These data demonstrate that multiple mechanisms guarantee increased Ag-induced mobilization of calcium in immature B cells and presumably ensure elimination of autoreactive B cells from the repertoire.

Early clinical outcomes after subfascial endoscopic perforator surgery (SEPS) and saphenous vein surgery in chronic venous insufficiency

BACKGROUND

Subfascial endoscopic perforator surgery (SEPS) has recently become popular as a minimally invasive way to treat chronic venous insufficiency (CVI) of the lower extremities. We report the early clinical outcomes of SEPS and saphenous vein surgery in a prospective series of Chinese patients who presented with severe CVI.

METHODS

All patients referred to our hospital for the management of severe CVI (class IV disease or above) after January 1998 underwent SEPS using an ultrasonic scalpel in conjunction with saphenous vein surgery. All patients were followed up prospectively to assess ulcer healing, ulcer recurrence, and symptoms after SEPS. Clinical outcome was evaluated by the scoring system suggested by the Consensus Committee of the American Venous Forum on Chronic Venous Disease.

RESULTS

Over a 24-month period, we performed 36 SEPS on 31 patients. Nineteen lower extremities (53%) had active or healing ulcers. Sapheno-femoral ligation was also performed in 33 limbs (92%). Four limbs (11%) developed superficial wound infection, and two (6%) had saphenous nerve dysesthesia. The mean clinical score and disability score decreased from 8.42 to 3.42 and 1.45 to 0.31 respectively, after a median follow-up of 14 months (range, 6-22) (p < 0.005). Eleven ulcers (58%) healed within 6 weeks after surgery. At 1-year follow-up, ulcer recurrence was found in two legs (11%).

CONCLUSION

SEPS is safe and feasible. Early clinical results have shown a promising outcome in patients with severe chronic venous insufficiency.

Development of follicular dendritic cell sarcoma in hyaline-vascular Castleman's disease of the nasopharynx: tracing its evolution by sequential biopsies

AIMS

Hyaline-vascular Castleman's disease (HVCD) and follicular dendritic cell (FDC) sarcoma occurring in the nasopharynx are both extremely rare. We report the first case of transformation of the former into the latter as documented by sequential biopsies. The steps involved in the transformation were described in detail and the possible role of p53 studied.

METHODS AND RESULTS

The patient presented at the age of 23 years with nasopharyngeal HVCD. Hyaline- vascular Castleman's disease with FDC overgrowth was diagnosed in a recurrence 8 years later, and a frank FDC sarcoma developed at the same site 11 years after initial presentation. The patient remained disease-free 3 years after excision and adjuvant chemotherapy. The FDC sarcoma comprised swirling fascicles of spindly cells with indistinct cell borders. The tumour cells expressed the FDC markers CD21, CD35 and CNA.42 and in-situ hybridization for Epstein-Barr virus-encoded RNAs was negative. Over-expression of p53 protein was observed in the FDC sarcoma and an increased number of weakly p53-positive spindly cells could also be demonstrated in the HVCD specimen. This finding suggested a possible role of p53 in the evolution from HVCD to FDC sarcoma. Critical analysis of the literature shows that, among the 13 reported cases of FDC sarcoma associated with Castleman's disease, possible progression from the latter to the former is documented in only two cases.

CONCLUSIONS

The sequential changes observed in the current case provide further evidence to strengthen the role of HVCD as a possible precursor of FDC sarcoma. There is a possible role of p53 in the transformation process but confirmation by future studies is needed.

Inflammatory pseudotumor-like follicular dendritic cell tumor: a distinctive low-grade malignant intra-abdominal neoplasm with consistent Epstein-Barr virus association

Follicular dendritic cell (FDC) tumors are uncommon neoplasms that can involve lymph nodes or extranodal sites. They can exhibit a broad spectrum of histologic appearances and behavior, but the intra-abdominal ones usually pursue an aggressive course. The purpose of this study was to characterize a distinctive variant of FDC tumor morphologically mimicking inflammatory pseudotumor through analysis of the clinicopathologic features of 11 cases. The patients included 10 women and one man (age range, 19-61 years; median age, 40 years) who presented with abdominal discomfort or pain. Six patients had systemic symptoms such as marked weight loss, fever, or malaise. All tumors occurred in intra-abdominal sites: liver (n = 7), spleen (n = 3), and peripancreatic region (n = 1). Of the nine patients with follow-up data, six were alive and well, one developed recurrence at 9 years, and two had repeated recurrences over many years. Grossly, the tumors were usually solitary and fleshy, punctuated by areas of hemorrhage and necrosis. Histologically, in a background of abundant lymphocytes and plasma cells were dispersed spindle or ovoid cells with vesicular nuclei and distinct nucleoli. The degree of nuclear atypia was variable, and some nuclei could be grotesque or resemble Reed-Sternberg cells. Focally, spindle cell fascicles could be formed. The atypical cells were immunoreactive for FDC markers such as CD21/CD35, CD23, and CNA.42. In situ hybridization for Epstein-Barr virus (EBV)-encoded RNA was positive in all cases, remarkably highlighting the spindle cells and their atypia. EBV-latent membrane protein-1 was expressed commonly, albeit often focally and weakly. Therefore, inflammatory pseudotumor-like FDC tumor represents a distinctive variant of FDC tumor that differs from conventional FDC tumor in the following aspects: marked female predominance; selective localization in intra-abdominal sites, especially the liver and spleen; frequent presence of systemic symptoms; indolent behavior despite an intra-abdominal location; dispersed distribution of tumor cells and prominent lymphoplasmacytic infiltration; and consistent association with EBV.

Immune system dysfunction and autoimmune disease in mice lacking Emk (Par-1) protein kinase

Emk is a serine/threonine protein kinase implicated in regulating polarity, cell cycle progression, and microtubule dynamics. To delineate the role of Emk in development and adult tissues, mice lacking Emk were generated by targeted gene disruption. Emk(-/-) mice displayed growth retardation and immune cell dysfunction. Although B- and T-cell development were normal, CD4(+)T cells lacking Emk exhibited a marked upregulation of the memory marker CD44/pgp-1 and produced more gamma interferon and interleukin-4 on stimulation through the T-cell receptor in vitro. In addition, B-cell responses to T-cell-dependent and -independent antigen challenge were altered in vivo. As Emk(-/-) animals aged, they developed splenomegaly, lymphadenopathy, membranoproliferative glomerulonephritis, and lymphocytic infiltrates in the lungs, parotid glands and kidneys. Taken together, these results demonstrate that the Emk protein kinase is essential for maintaining immune system homeostasis and that loss of Emk may contribute to autoimmune disease in mammals.

Management of paraffinoma of the breast: 10 years' experience

Paraffin injection was regarded as a simple and effective method of improving body contour. It was widely used in breast augmentation until the long-term complication of paraffinoma was recognised. Paraffinoma of the breast can present as a spectrum of disease ranging from a painless mass to a destructive ulcer simulating breast cancer. This makes it difficult to make the correct diagnosis and provide suitable treatment. Eight patients with paraffinoma of the breast have been managed at a teaching hospital over a 10 year period. All were females, with a mean age of 65.6 years (range: 57-73 years). The average time between paraffin injection and the onset of symptoms was 24 years (range: 11-30 years). These patients have been followed up for between 3 and 10 years (mean: 6.1 years). One patient died of congestive heart failure 4 years after bilateral mastectomy for painful paraffinomas of the breasts. Another patient had a coexisting infiltrative ductal carcinoma of the breast. The clinical presentations, radiological appearances, histopathological features and the treatment are discussed.

[Detection of Immunoglobulin light chain restriction of mucosa-associated lymphoid tissue type gastric lymphoma using mRNA in situ hybridization]

OBJECTIVE

To evaluate the usefulness of in situ hybridization for Immunoglobulin kappa and lambda light chain mRNA to detect light chain restriction in the diagnosis of primary gastric lymphoma (PGL) of mucosa-associated lymphoid tissue (MALT) type.

METHODS

Twenty-seven cases of PGL of MALT type and 5 cases of gastritis were analyzed using in situ hybridization with fluorescent isothiocyanate (FITC)-labeled oligonucleotide probes for kappa and lambda light chain mRNA. The kappa:lambda ratios of tumor cells, lymphocytes and plasma cells were analyzed to detect light chain restriction and clonal plasma cells.

RESULTS

Light chain restriction was found in 10 of 27 (37%) cases of PGL cases (in 5/9 low grade and 5/18 in high grade). Clonal plasma cells were detected in low grade but not in high-grade cases. No light chain restriction was found in gastritis specimens, the adjacent tissue of tumors or the distant stomach mucosa in lymphoma cases.

CONCLUSIONS

The detection of clonality using mRNA in situ hybridization could be a helpful diagnostic tool for gastric lymphoma. The presence of clonal plasma cells can be a marker of the early lesion of low-grade PGL.