Clinicopathologic features and diagnostic challenges of small cluster pattern appendiceal neuroendocrine tumors

Appendiceal neuroendocrine neoplasms (NENs) can present with various growth patterns including the traditional triad of histologic patterns-insular, trabecular and tubular. A small cluster pattern was also found in this study and the literature on this specific morphology is limited. In this study, we conducted a comprehensive review of appendiceal NENs from our institution over a ten-year period. Clinical and demographic data were obtained from medical records. Immunohistochemical stains were performed with antibodies specific for synaptophysin, chromogranin, INSM1, CD56, serotonin and peptide YY. The small cluster pattern was found in 29.4 % of all cases evaluated. The tumor cells in these cases were predominantly located at the distal tip of the appendix, associated with fibrous obliteration. These tumors were smaller in size and tended towards less advanced tumor stage, with reduced incidence of lymphovascular and/or perineural invasion. Chromogranin expression was identified in 76 % of these cases. There is a heterogeneous hormone profile with 46.7 % serotonin and 33.3 % peptide YY. In conclusion, the small cluster pattern NENs present with unique histological features and hormone expression profile. Among the various neuroendocrine markers, INSM1 showed superior diagnostic performance, with high sensitivity and minimal non-specific staining.

Immunohistochemical Evaluation of NKP46 Receptor Expression and the Number of NK Cells in the Endometrium of Patients with Endometriosis

Background

Endometriosis is a medical condition that can cause infertility in women. Women with endometriosis experience a decrease in NK cell cytotoxic activity against endometrial cells, ultimately contributing to the spread of these cells.

Objective

To assess the frequency of NK cells and the expression of the NKP46 receptor in endometrial tissue from patients with endometriosis using immunohistochemistry.

Methods

30 endometrial tissue specimens were collected from three groups of cases with mild (n=11), moderate (n=10), and severe endometriosis (n=9), respectively. Additionally, 20 normal endometrial tissue specimens were collected as the control group. Immunohistochemical staining was carried out using specific human monoclonal antibodies against CD56 and NKP46 molecules.

Results

Cases with severe endometriosis had a significantly higher number of CD56+ uterine NK cells (26.19±2.50) compared to fertile women (15.02±0.622) and women with mild to moderate endometriosis (p<0.001). However, there was no significant difference between the mild to moderate patients compared with the healthy women (p>0.05). Endometrial NKp46 expression was lower in women with severe endometriosis (0.447±0.0829) compared to fertile women (0.987±0.115, p=0.03). The NKp46+/CD56+ cell ratio was also lower in women with severe endometriosis (0.019±0.003) compared to fertile women (0.072±0.011, p=0.01).

Conclusion

Women with severe endometriosis demonstrated an increased rate of infiltrated uterine NK cells and a significant decrease in NKP46 expression compared to fertile women. Therefore, NK cells and the NKp46 receptor may be involved in the development of endometriosis.

Expression and Clinical Significance of CD30 and CD56 in Lymphoblastic Lymphoma: A Retrospective Analysis on Paraffin-Embedded Tissues by Immunohistochemistry

Background: We evaluated CD30 and CD56 expression in lymphoblastic lymphoma (LBL) and correlated the results with clinicopathological features and prognosis. Methods: Immunohistochemical (IHC) staining was performed on 85 formalin-fixed paraffin-embedded LBL specimens using two CD30 clones and one CD56 antibody clone. Results: Weak and diffuse expression of CD30 was expressed in 4.7% (clone Ber-H2) or 14.1% (clone EPR4102) in LBL, while CD56 was expressed in 24.7%. CD30 and CD56 expression correlated with lactate dehydrogenase levels. CD56-positive expression was closely associated with an unfavorable prognosis. Although CD30 expression exhibited a trend toward poorer overall survival, it did not reach statistical significance. Conclusion: CD56 is a potential negative prognostic marker. These findings suggest that CD30 and CD56 targeted therapies could be potential therapeutic targets for LBL patients.

Prognostic implications of synaptophysin, CD56, thyroid transcription factor-1, and Ki-67 in pulmonary high-grade neuroendocrine carcinomas

BACKGROUND

The correlation between the expression of immunohistochemical markers and the clinicopathological characteristics of pulmonary high-grade neuroendocrine carcinomas (HGNEC) and its impact on the clinical outcomes of individuals with HGNEC has not yet been explored.

METHODS

This study enrolled patients diagnosed with HGNEC between April 2015 and July 2023. Based on the expression levels of synaptophysin (Syn), the neural cell adhesion molecule (CD56), thyroid transcription factor-1 (TTF-1), and Ki-67, a comprehensive analysis was conducted. This involved a comparison of clinicopathological characteristics, chemosensitivity, overall survival (OS), and progression-free survival (PFS). Furthermore, the study identified prognostic factors associated with patient survival through univariate and multivariate analyses.

RESULTS

Eighty-two patients were analyzed. Significant differences were identified in tumor stage (χ2 = 5.473, P = 0.019), lymphatic invasion (χ2 = 8.839, P = 0.003), and distant metastasis (χ2 = 5.473, P = 0.019), respectively, between the CD56 positive and negative groups. A significant difference in lymphatic invasion was observed (χ2 = 9.949, P = 0.002) between the CD56 positive and negative groups. A significant difference in vascular invasion was observed (χ2 = 5.106, P = 0.024) between the low and high Ki-67 groups. Compared to the Syn negative group, the Syn positive group had significantly shorter PFS (P = 0.006). Compared to the Syn negative group, the Syn positive group had significantly shorter OS (P = 0.004). The CD56 positive group also had significantly shorter OS than the CD56 negative group (P = 0.027). Univariate analysis revealed that tumor stage and Syn expression were associated with OS and PFS. Lymphatic invasion and CD56 expression were associated with OS. Multivariate analysis revealed that tumor stage was the strongest predictor of poor prognosis for OS (hazard ratio [HR] 0.551, 95 % confidence interval [CI] 0.328-0.927, P = 0.025) and PFS (HR 0.409, 95 % CI 0.247-0.676, P < 0.001).

CONCLUSIONS

Positive expression of Syn was associated with reduced PFS and OS, while positive CD56 expression was correlated with a shorter OS in HGNEC. The TNM stage was an independent risk factor that significantly influenced PFS and OS in patients with HGNEC. More studies are needed to make further progress in future treatment.

Prevalence and clinical impact of CD56 and T-cell marker expression in acute myeloid leukaemia: A single-centre retrospective analysis

Flow cytometry-based immunophenotyping is a mainstay of diagnostics in acute myeloid leukaemia (AML). Aberrant CD56 and T-cell antigen expression is observed in a fraction subset of AML cases, but the clinical relevance remains incompletely understood. Here, we retrospectively investigated the association of CD56 and T-cell marker expression with disease-specific characteristics and outcome of 324 AML patients who received intensive induction therapy at our centre between 2011 and 2019. We found that CD2 expression was associated with abnormal non-complex karyotype, NPM1 wild-type status and TP53 mutation. CD2 also correlated with a lower complete remission (CR) rate (47.8% vs. 71.6%, p = 0.03). CyTdT and CD2 were associated with inferior 3-year event-free-survival (EFS) (5.3% vs. 33.5%, p = 0.003 and 17.4% vs. 33.1%, p = 0.02, respectively). CyTdT expression was also correlated with inferior relapse-free survival (27.3% vs. 48.8%, p = 0.04). In multivariable analyses CD2 positivity was an independent adverse factor for EFS (HR 1.72, p = 0.03). These results indicate a biological relevance of aberrant T-cell marker expression in AML and provide a rationale to further characterise the molecular origin in T-lineage-associated AML.

A CD56- immunoblastoid variant of blastic plasmacytoid dendritic cell neoplasm

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is an aggressive malignant hematologic neoplasm arising from plasmacytoid dendritic cells. It is a very rare tumor that constitutes less than 0.1% of all hematologic malignancies. Most patients with BPDCN present clinically with cutaneous lesions as the first sign of disease. Immunophenotypic variability with aberrant marker profiles has been reported. We report a case of a transcription factor 4 (TCF-4) + BPDCN, with negative CD56 expression in an 85-year-old woman with multiple skin nodules. A punch biopsy revealed a diffuse, monomorphous, and non-epidermotropic cell infiltrate involving the entire dermis. The infiltrate was composed of intermediate-sized cells with immunoblastoid morphology, which is an unusual morphologic variant. The neoplastic cells were strongly positive for CD45 and co-expressed CD4, CD123, TCF-4, BCL-2, and CD10. The Ki-67 proliferative rate was very high (90%). Negative immunostains included CD56, an unusual finding in BPDCN. This case illustrates the challenges encountered in the diagnosis of this entity, particularly in unusual morphologic variants and phenotypes. The elucidation of molecular signatures and development of targeted therapies for its management have been recently introduced and differ from acute myeloid leukemias. Hence, accurate diagnosis of BPDCN is critical for dermatopathologists.

Developing a Cell-Microcarrier Tissue-Engineered Product for Muscle Repair Using a Bioreactor System

Fecal incontinence, although not life-threatening, has a high impact on the economy and patient quality of life. So far, available treatments are based on both surgical and nonsurgical approaches. These can range from changes in diet, to bowel training, or sacral nerve stimulation, but none of which provides a long-term solution. New regenerative medicine-based therapies are emerging, which aim at regenerating the sphincter muscle and restoring continence. Usually, these consist of the administration of a suspension of expanded skeletal-derived muscle cells (SkMDCs) to the damaged site. However, this strategy often results in a reduced cell viability due to the need for cell harvesting from the expansion platform, as well as the non-native use of a cell suspension to deliver the anchorage-dependent cells. In this study, we propose the proof-of-concept for the bioprocessing of a new cell delivery method for the treatment of fecal incontinence, obtained by a scalable two-step process. First, patient-isolated SkMDCs were expanded using planar static culture systems. Second, by using a single-use PBS-MINI Vertical-Wheel® bioreactor, the expanded SkMDCs were combined with biocompatible and biodegradable (i.e., directly implantable) poly(lactic-co-glycolic acid) microcarriers prepared by thermally induced phase separation. This process allowed for up to 80% efficiency of SkMDCs to attach to the microcarriers. Importantly, SkMDCs were viable during all the process and maintained their myogenic features (e.g., expression of the CD56 marker) after adhesion and culture on the microcarriers. When SkMDC-containing microcarriers were placed on a culture dish, cells were able to migrate from the microcarriers onto the culture surface and differentiate into multinucleated myotubes, which highlights their potential to regenerate the damaged sphincter muscle after administration into the patient. Overall, this study proposes an innovative method to attach SkMDCs to biodegradable microcarriers, which can provide a new treatment for fecal incontinence.

CD56/NCAM mediates cell migration of human NK cells by promoting integrin-mediated adhesion turnover

Natural killer (NK) cells patrol tissue to mediate lysis of virally infected and tumorigenic cells. Human NK cells are typically identified by their expression of neural cell adhesion molecule (NCAM, CD56), yet, despite its ubiquitous expression on NK cells, CD56 remains a poorly understand protein on immune cells. CD56 has been previously demonstrated to play roles in NK cell cytotoxic function and cell migration. Specifically, CD56-deficient NK cells have impaired cell migration on stromal cells and CD56 is localized to the uropod of NK cells migrating on stroma. Here, we show that CD56 is required for NK cell migration on ICAM-1 and is required for the establishment of persistent cell polarity and unidirectional actin flow. The intracellular domain of CD56 (NCAM-140) is required for its function, and the loss of CD56 leads to enlarged actin foci and sequestration of phosphorylated Pyk2, accompanied by increased size and frequency of activated LFA-1 clusters. Together, these data identify a role for CD56 in regulating human NK cell migration through modulation of actin dynamics and integrin turnover.

Immunohistochemical study of the expressed cluster differentiation markers proteins type 20 and 56 in breast tissues from a group of Iraqi patients with breast cancers

BACKGROUND

Tumor-infiltrating lymphocytes (TIL) are important immunological components in response to cancers. Patients with higher numbers of TIL in breast cancerous tissues, comprising T- cytotoxic and T - helper cells along with B- and rare natural killer (NK) cells, have more favorable clinical outcomes.

OBJECTIVE

To analyze the rate of the expressed surface biomarker proteins of CD20-B cells and CD56- NK cells on the infiltrative lymphocytic subpopulations in a group of breast tumorous tissues (invasive and benign) from female patients in Iraq and explore the relations to the grade of the invasive breast cancerous tissues.

PATIENTS AND METHODS

One hundred and 75 archived breast tissues were enrolled in this retrospective research: 100 archived breast from female patients with invasive breast cancers (BC) [20 well differentiated BC tissues; 48 moderately differentiated BC and 32 poorly differentiated BC tissues]; 50 tissue biopsies from female patients with benign breast tumors and 25 apparently normal individuals with healthy breast tissues (included as the control group for this study). Immunohistochemistry was achieved for the detection of the expressed surface biomarker proteins related to B cell CD20 and NK cell CD56 present on the infiltrative lymphocytic subpopulations in breast tissues by using specific primary antibodies for these proteins via utilizing an immune-enzymatic antigen detection system.

RESULTS

The detection of IHC reactions for the expressed B cell CD20 - cell surface ( CD) biomarker proteins were observed in 53 out of 100 (53.0%) BC tissues, and in 24 out of 50 (48.0%) benign breast tumorous tissues, while CD20- positive cell surface markers was detected in apparently healthy breast tissues of the control group in a percentage of  32.0% (8 out of 25 tissues). Statistical significant differences (P<0.05) between both groups of malignant and benign breast tumors and the control group were found. However, between breast malignant and benign tumor groups, no significant difference was found ( p >0.05). Detection of CD56- IHC reactions revealed in 14% (14  out of 100 BC tissues), in 16% (8 out of 50 benign breast tissues) and none of control breast tissues revealed CD56- IHC reactions. Among all the enrolled groups, no significant differences (P>0.05) were detected.

CONCLUSIONS

The observed significant rates that showed highly significant differences  between both  studied groups of breast malignant and benign tumor in comparison to the control group indicate that the CD20- positive infiltrative B cell- lymphocytic subpopulations might contributed in the defense against these subsets of benign and malignant breast tumors. However, the observed rates of NK cell CD56 present on the lymphocytic subpopulations infiltrating the examined malignant and benign breast tumorous tissues  seeming to play  irrelevant roles in the defense against  these studied breast tumor groups.

Plasma Cell Leukemia-Clinicopathological Profile from a Tertiary Care Center in Western India

Poornima ManimaranIntroduction  Plasma cell leukemia (PCL) is very uncommon and aggressive neoplasm constituting 2 to 4% of all plasma cell dyscrasias. By definition, clonal plasma cells should make up 20% of peripheral blood or have an absolute plasma cell count of 2 × 10 9 cells/cu.mm. PCL can be primary or secondary. In this study, the clinicohematological features of PCL, and correlation of immunophenotypic profile and conventional therapies with overall survival was analyzed. Materials and Methods  This retrospective study involved PCL patients who were diagnosed across a 12-year period, from 2010 to 2021, at a tertiary care center in western India. Clinical, biochemical, peripheral smear, bone marrow aspirate, immunophenotyping, and molecular analysis were performed. Results  Total 39 PCL patients were included in the study among which 36 were primary PCL patients. Splenomegaly (10/27), hepatomegaly (6/26), and lymphadenopathy (5/23) were noted. At presentation, all patients had anemia (<11g/dL), thrombocytopenia (33/39), hypercalcemia (>11mg/dl) 10/33 (30.3%) and lytic lesions was noted in 18/26 (69.2%). Immunophenotype of these patients showed CD 38 positivity, CD 138 positivity, CD56 positivity, and CD 117 negativity were 100, 62, 41.6, and 89%, respectively. Overall survival of our patients was 4.1 months and overall survival of patients treated with VTD (bortezomib, thalidomide, dexamethasone) and VCD (bortezomib, cyclophosphamide, dexamethasone) regimen was 3.4 and 4.1 months, respectively, which was not statically significant ( p -value 0.816). CD117 and CD56 markers were also not having any prognostic significance ( p -value 1.000 and 0.873, respectively). Conclusion  Because of rarity of the disease, prospective studies are very limited and hence management and outcome of the disease are difficult to analyze. The current treatment protocols have no survival advantage and hence newer therapeutic approach is mandatory to attain better outcome.

Flow cytometry improves the diagnostic value of fine needle aspiration cytology in a spleen with neuroendocrine tumor: A case report

Fine needle aspirations are infrequently performed on the spleen due to concerns for hemorrhagic complications. As a result, splenic lesions can be challenging to diagnose given the limited amount of available specimen. Metastasis to the spleen is rare and metastatic neuroendocrine tumors to the spleen are scarce in literature. The diagnosis of splenic lesions from fine needle aspirate entails processing which prolongs the turnaround time, particularly if the cytomorphology is non-typical and a limited sample can further complicate this process. We describe a case in which flow cytometry performed on fine needle aspiration of a splenic lesion suggested a diagnosis of neuroendocrine neoplasm involving the spleen. Further workup confirmed this diagnosis. Flow cytometry can recognize neuroendocrine tumors involving the spleen in a timely manner so that appropriate immunohistochemistry tests on limited specimens can be performed to aid in their accurate diagnosis.

Investigation of CD56, ADAM17 and FGF21 Expressions in the Placentas of Preeclampsia Cases

Objective: In the present study, we investigated the expression of CD56, ADAM17 and FGF21 antibodies (Ab), which we think have an effect on the pathophysiology of preeclampsia (PE), in pregnant patients with healthy placentas and placentas with PE. The expression of these antibodies has been investigated in a limited amount of former research, but their role in PE has not yet been clarified. With this study, we aimed to contribute to the elucidation of the pathophysiology of PE and the detection of new target molecules for treatment. Materials and Methods: Parturients with singleton pregnancy at 32 weeks or above without any maternal or fetal pathology who were admitted to the Department of Obstetrics and Gynecology, Zonguldak Bülent Ecevit University Practice and Research Hospital between 11 January 2020 and 7 January 2022 were included in the present study. Pregnant women with coexisting disease or a pathology related to the placenta (ablation placenta, vasa previa, hemangioma, etc.) were excluded. CD56, ADAM17 and FGF21 antibodies were histopathologically and immunohistochemically detected in 60 placentas with PE (study group) and 43 healthy placentas (control group). Results: CD56, ADAM17 and FGF21 proteins were all more intensely expressed in preeclamptic placentas and a statistically significant difference was found between the two groups for all three antibodies (p < 0.001). Deciduitis, perivillous fibrin deposition, intervillous fibrin, intervillous hemorrhage, infarct, calcification, laminar necrosis and syncytial node were found to be significantly more common in the study group (p < 0.001). Conclusions: We observed that CD56, ADAM17 and FGF21 expressions increased in preeclamptic placentas. These Ab may be responsible for the pathogenesis of PE, which can be illuminated with further studies.

Immunophenotypic expression profile of multiple myeloma cases at a tertiary hospital in Nairobi Kenya

Introduction

Multiple myeloma (MM) is a plasma cell neoplasm that constitutes 10-15% of all hematopoietic neoplasms. Kenya is placed among the top five African countries for MM incidence and MM-related mortality. Prior studies have suggested that the aberrant expression of Cyclin D1, CD56, CD117 and Ki-67 on neoplastic plasma cells is useful in disease prognostication. The prevalence and significance of expression of these markers in a cohort of MM cases in Kenya has not been studied previously.

Methods

A retrospective cross-sectional study was carried out at the Aga Khan University Hospital, Nairobi. The study population included 83 MM cases with available trephine blocks archived between 1st of January 2009 and 31st of March 2020. Immunohistochemical expression of Cyclin D1, CD56, CD117, and Ki-67 was analyzed and scored. The biomarkers were described using frequencies based on the positive and negative results. Fisher's exact test was used to determine the association between the immunophenotypic markers and categorical variables.

Results

Of the 83 selected cases, expression of Cyclin D1, CD56, CD117 and Ki-67 was identified in 28.9, 34.9, 7.2, and 50.6%, respectively. Cyclin D1 positivity was significantly associated with hypercalcemia. Absence of CD117 expression was noted to be associated with adverse risk parameters including an IgA isotype or light chain disease, International Staging System (ISS) stage III disease, abnormal baseline serum free light chains (sFLC) and a high plasma cell burden.

Conclusion

Cyclin D1 expression was congruent with previously reported studies. The frequency of CD56 and CD117 expression was lower than previously reported. This may be due to differences in disease biology between the study populations. Approximately half of cases were Ki-67 positive. Our data showed limited associations between the expression of studied markers and clinicopathologic variables. However, this could be attributed to the small study sample size. We would recommend further characterization of the disease in a larger prospective study with the inclusion of survival outcomes and cytogenetic studies.

Natural killer cell subset count and antigen-stimulated activation in response to exhaustive running following adaptation to a ketogenic diet

NEW FINDINGS

What is the central question of this study? Does a ketogenic diet (KD) modulate circulating counts of natural killer (NK) cells, including CD56bright and CD56dim subsets, and their ability to activate (CD69 expression) following in vitro antigen stimulation in response to exhaustive moderate-intensity exercise? What is the main finding and its importance? The KD amplified the biphasic exercise-induced NK cell response due to a greater mobilisation of the cytotoxic CD56dim subset but did not alter NK cell CD69 expression. The KD appears to modulate exercise-induced circulating NK cell mobilisation and egress, but not antigen-stimulated circulating NK cell activation.

ABSTRACT

We investigated the effect of a 31-day ketogenic diet (KD) compared with a habitual, carbohydrate (CHO)-based diet on total circulating natural killer (NK) CD3- CD56+ , dim and bright subset count, and antigen-stimulated CD3- CD56+ cell activation (CD69+ ) in response to exhaustive running. In a randomised, repeated-measures, cross-over study, eight trained, male endurance athletes ingested a 31-day low-CHO KD or their habitual diet (HD). On day 31, participants ran to exhaustion at 70%V ̇ O 2 max $\dot{V}_{{\rm{O}}_{2}{\rm{max}}}$ (∼3.5-4 h, ∼45-50 km). A low-CHO (<10 g) meal was ingested prior to the KD trial, with fat ingested during exercise. A high-CHO (2 g kg-1 ) meal was ingested prior to the HD trial, with CHO (∼55 g h-1 ) ingested during exercise. Venous blood samples were collected at pre-exercise, post-exercise and 1 h post-exercise. The KD amplified the classical exercise-induced biphasic CD3- CD56+ cell response by increasing the post-exercise counts (P = 0.0004), which appeared to be underpinned by the cytotoxic CD3- CD56dim subset (main effect of time point, P < 0.0001). The KD had no effect on NK cells' expression of CD69 or their geometric mean fluorescence intensity of CD69 expression, either for unstimulated or for antigen-stimulated NK cells (all P > 0.05). In conclusion, adaptation to a KD may alter the number of circulating NK cells but not their ability to activate to an antigenic challenge.

Characterization of Tumor and Immune Tumor Microenvironment of Primary Tumors and Metastatic Sites in Advanced Renal Cell Carcinoma Patients Based on Response to Nivolumab Immunotherapy: Preliminary Results from the Meet-URO 18 Study

BACKGROUND

Prognostic and predictive factors for patients with metastatic renal cell carcinoma (mRCC) treated with immunotherapy are highly warranted, and the immune tumor microenvironment (I-TME) is under investigation.

METHODS

The Meet-URO 18 was a multicentric retrospective study assessing the I-TME in mRCC patients treated with ≥2nd-line nivolumab, dichotomized into responders and non-responders according to progression-free survival (≥12 months and ≤3 months, respectively). The primary objective was to identify differential immunohistochemical (IHC) patterns between the two groups. Lymphocyte infiltration and the expressions of different proteins on tumor cells (CD56, CD15, CD68, and ph-mTOR) were analyzed. The expression of PD-L1 was also assessed.

RESULTS

A total of 116 tumor tissue samples from 84 patients (59% were primary tumors and 41% were metastases) were evaluated. Samples from responders (N = 55) were significantly associated with lower expression of CD4+ T lymphocytes and higher levels of ph-mTOR and CD56+ compared with samples from non-responders (N = 61). Responders also showed a higher CD3+ expression (p = 0.059) and CD8+/CD4+ ratio (p = 0.084). Non-responders were significantly associated with a higher percentage of clear cell histology and grading.

CONCLUSIONS

Differential IHC patterns between the tumors in patients who were responders and non-responders to nivolumab were identified. Further investigation with genomic analyses is planned.

[Blastic plasmacytoid dendritic cell neoplasm: A clinico-pathological retrospective analysis of thirteen cases]

OBJECTIVE

To investigate the clinicopathological features of blastic plasmacytoid dendritic cell neoplasm (BPDCN).

METHODS

A total of 13 cases of BPDCN diagnosed in Peking University First Hospital from January 2013 to March 2022 were collected. The clinical features, histopathological characteristics, immunophenotypes and prognosis of the patients were analyzed retrospectively, and the related literatures was reviewed as well.

RESULTS

Among the 13 patients, 11 were male and 2 were female, with a median age of 62 years (ranging from 5 to 78 years). Among them, single organ involvement occurred in 5 cases, all of which presented with skin lesions. Two or more organs were involved in other 8 cases (single organ with bone marrow involved in 3 cases; skin, bone marrow and lymph node involved simultaneously in 3 cases; skin, bone marrow, lymph node and spleen involved simultaneously in 2 cases). Histopathologically, it was characterized by the proliferation of medium to large atypical blastic cells, which infiltrated the whole thickness of dermis. When involved, the bone marrow lesions mainly appeared in a diffuse pattern, while the lymph node structure was usually destroyed, and the red pulp of the affected spleen was diffusely invaded. Immunohistochemical staining showed that all the 13 cases were positive for CD4, CD56, and CD123 (13/13) in varying degrees. All the 9 cases expressed TCL1 (9/9). Variable expression of CD68 (KP1) (8/13), TdT (7/12), CD117 (2/6), and high Ki-67 proliferation index (40%~80%) were showed. The neoplastic cells lacked expressions of CD20, CD3, MPO, CD34, or CD30; EBER in situ hybridization were negative (0/9). After definite diagnosis, 6 cases received chemotherapy, among which 1 received adjuvant radiotherapy, and 2 received subsequent bone marrow transplantation. Another 2 cases only received maintenance treatment. The median follow-up time was 14 months (ranging from 6 to 36 months), 5 patients died of the disease (6 to 18 months), 3 patients survived (7 to 36 months up to now), and the remaining 5 patients lost follow-up.

CONCLUSION

BPDCN is a rare type of malignant lymphohematopoietic tumor with aggressive behavior and poor prognosis. The diagnosis should be made combining clinical features, histopathology, and immunohistochemical phenotype. Attention should be paid to differentiating BPDCN from other neoplasms with blastoid morphology or CD4+CD56+ tumors.

CD56-positive diffuse large B-cell lymphoma: comprehensive analysis of clinical, pathological, and molecular characteristics with literature review

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma. The expression of CD56 in DLBCL is highly unusual. Little is known about its incidence and clinical importance. So far, no genetic profiling was performed in CD56 positive DLBCL.

PATIENTS AND METHODS

Tissue microarrays have been constructed, sectioned, and stained by H&E and immunohistochemistry for 229 patients with DLBCL diagnosed 2008-2017. For CD56 positive cases, clinical data was collected including age at diagnosis, stage of the disease, International Prognostic Index (IPI) score, treatment scheme and number of chemotherapy cycles, radiation therapy, treatment outcome, and possible relapse of the disease. Overall survival (OS) and progression-free survival (PFS) were calculated. For four patients, RNA was extracted and targeted RNA (cDNA) sequencing of 125 genes was performed with the Archer FusionPlex Lymphoma kit.

RESULTS

CD56 expression was found in 7 cases (3%). The intensity of expression varied from weak to moderate focal, to very intensive and diffuse. All patients had de novo DLBCL. The median age at the time of diagnosis was 54.5 years. Five of them were women and 2 males. According to the Hans algorithm, 6 patients had the germinal centre B cells (GBC) type and one non-GBC (activated B-cell [ABC]) type, double expressor. Genetic profiling of four patients according to Schmitz's classification showed that 1 case was of the BN2 subtype, 1 of EZB subtype, 2 were unclassified. The six treated patients reached a complete response and did not experience progression of the disease during the median follow-up period of 80.5 months.

CONCLUSIONS

We report on one of the largest series of CD56+DLBCL with detailed clinicopathological data and for the first time described genetical findings in a limited number of patients. Our results show that CD56 expression is rare, but seems to be present in prognostic favourable subtypes of DLBCL not otherwise specified (NOS) as tested by immunohistochemical or genetic profiling.

A novel combination for the treatment of small cell lung cancer: Active targeted irinotecan and stattic co-loaded PLGA nanoparticles

Polymeric nanoparticles are widely used drug delivery systems for cancer treatment due to their properties such as ease of passing through biological membranes, opportunity to modify drug release, specifically targeting drugs to diseased areas, and potential of reducing side effects. Here, we formulated irinotecan and Stattic co-loaded PLGA nanoparticles targeted to small cell lung cancer. Nanoparticles were successfully conjugated with CD56 antibody with a conjugation efficiency of 84.39 ± 1.01%, and characterization of formulated nanoparticles was conducted with in-vitro and in-vivo studies. Formulated particles had sizes in the range of 130-180 nm with PDI values smaller than 0.3. Encapsulation and active targeting of irinotecan and Stattic resulted in increased cytotoxicity and anti-cancer efficiency in-vitro. Furthermore, it was shown with ex-vivo biodistribution studies that conjugated nanoparticles were successfully targeted to CD56-expressing SCLC cells and distributed mainly to tumor tissue and lungs. Compliant with our hypothesis and literature, the STAT3 pathway was successfully inhibited with Stattic solution and Stattic loaded nanoparticles. Additionally, intravenous injection of conjugated co-loaded nanoparticles resulted in decreased side effects and better anti-tumor activity than individual solutions of drugs in SCLC tumor-bearing mice. These results may indicate a new treatment option for clinically aggressive small cell lung cancer.

Mild Hyperbaric Oxygen Exposure Enhances Peripheral Circulatory Natural Killer Cells in Healthy Young Women

Mild hyperbaric oxygen (HBO) enhances oxygen absorption in blood, relieving fatigue without causing oxidative stress. The benefits of mild HBO have been recognized in the treatment of lifestyle-related diseases and hypertension, but no research has been conducted on its effects on immunity. The aim of the present study is to investigate the effect of mild HBO on natural killer (NK) cells and cytokines in healthy young women. This crossover randomized control trial was conducted with 16 healthy young women. Participants were randomly exposed to normobaric oxygen (NBO; 1.0 atmospheres absolute (ATA), 20.8% oxygen) and mild HBO conditions (1.4 ATA, 35-40% oxygen, injected 18L oxygen per minute) in a hyperbaric oxygen chamber for 70 min. Heart rate, parasympathetic activity, NK cell count, interleukin (IL)-6, IL-12p70 and derivatives of reactive oxygen metabolites (d-ROMs) were measured before and after both exposures. In the NBO condition, parasympathetic activity remained unchanged, whereas after mild HBO exposure, parasympathetic activity was significantly increased. NK cells remained unchanged after NBO exposure, while NK cells were increased after exposure to mild HBO. Exposure to mild HBO did not increase d-ROM values, IL-6 and IL-12p70 protein levels. These findings suggest that exposure to mild HBO can be a useful protocol to increase NK cells by regulating parasympathetic activity via increasing oxygen delivery.

Retrospective Analysis of the Expression of CD56 in Multiple Myeloma with Bone-Related Extramedullary Diseases

OBJECTIVE

To identify the clinical characteristics and tissue CD56 expression pattern in patients with multiple myeloma (MM) with bone-related extramedullary disease (b-EMD), not connected to or isolated from the bone marrow.

METHODS

We reviewed consecutive patients with MM hospitalised at the First Affiliated Hospital of Fujian Medical University between 2016 and 2019. Patients with b-EMD were identified, and the clinical and laboratory features of patients with and without b-EMD were compared. Immunohistochemistry of extramedullary lesions was performed based on b-EMD histology.

RESULTS

Ninety-one patients were included in the study. Among them, 19 (20.9%) were found to have b-EMD at initial diagnosis. Median age was 61 years (range, 42-80 years), with a female/male ratio of 6/13. The most common site of b-EMD was the paravertebral space (11/19; 57.9%). Compared to those without b-EMD, patients with b-EMD had lower levels of serum β2-microglobulin and similar levels of lactate dehydrogenase. Immunophenotype analysis based on histopathology showed that CD56 was expressed in 9/10 (90.0%) patients with b-EMD.

CONCLUSION

A considerable number of MM patients presented with b-EMD at the time of initial diagnosis, and most patients with b-EMD exhibited CD56 expression, highlighting a potential new therapeutic target in the future.

Extra Eyelid-Derived Muscle Stem Cells

Skeletal muscle stem cells (MuSCs) have been proposed as suitable candidates for cell therapy to muscular disorders since they exhibit a good capacity for myogenic regeneration. However, for better therapeutic outcomes, it is necessary to isolate human MuSCs from a suitable tissue source that possess high myogenic differentiation. In this context, isolated CD56+CD82+ cells from extra eyelid tissues were tested in vitro myogenic differentiation potential. Primary human myogenic cells derived from extra eyelids including orbicularis oculi, might be good candidates for human muscle stem cell-based research.

CD56 and smooth muscle actin immunoreactivity in basal cell carcinomas: Are they indicators of differentiation or do they hold a diagnostic use?

BACKGROUND

Basal cell carcinoma (BCC) is the most common cutaneous malignancy and may show various differentiations. The possible pluripotent stem cell lineage of BCCs, whose origins are controversial today, is thought to be the main reason for the different morphologies. The aim of the study is to evaluate the expression of some neuroendocrine and smooth muscle markers of differentiation in BCCs and investigate the relationship between histopathologic subtypes and recurrence.

METHODS

A total of 128 cases diagnosed as BCC in our center were included. Immunohistochemical studies of CD56, synaptophysin, chromogranin-A, smooth muscle actin (SMA), desmin, caldesmon, and Ki67 were applied.

RESULTS

CD56, chromogranin-A, and synaptophysin immunoreactivity were detected in 77.3%, 13.3%, and 0.8% of the cases, respectively. 78.1% showed SMA positivity while no tumor expressed desmin or caldesmon. A correlation between histopathologic recurrence risk groups and CD56 expression was found (p < 0.05).

CONCLUSIONS

CD56 and SMA immunoreactivity is present in the majority of BCCs. However, the available findings do not support neuroendocrine or smooth muscle differentiation. CD56 antigen can be used for prognostic purposes in detecting high recurrence risk tumors. After the investigation of the expression rates of these two antigens in different cutaneous tumors, it may be appropriate to use them for diagnostic purposes in BCCs.

KLRF1, a novel marker of CD56bright NK cells, predicts improved survival for patients with locally advanced bladder cancer

BACKGROUND

Bladder tumor-infiltrating CD56^bright NK cells are more tumor cytotoxic than their CD56^dim counterparts. Identification of NK cell subsets is labor-intensive and has limited utility in the clinical setting. Here, we sought to identify a surrogate marker of bladder CD56^bright NK cells and to test its prognostic significance.

METHODS

CD56^bright and CD56^dim NK cells were characterized with the multiparametric flow (n = 20) and mass cytometry (n = 21) in human bladder tumors. Transcriptome data from bladder tumors (n = 351) profiled by The Cancer Genome Atlas (TCGA) were analyzed. The expression levels of individual markers in intratumoral CD56^bright and CD56^dim NK cells were visualized in tSNE plots. Expressions of activation markers were also compared between Killer Cell Lectin-Like Receptor Subfamily F Member 1 (KLRF1)⁺ and KLRF1^- NK cells.

RESULTS

Intratumoral CD56^bright NK cells displayed a more activated phenotype compared to the CD56^dim subset. Multiple intratumoral cell types expressed CD56, including bladder tumor cells and nonspecific intratumoral CD56 expression was associated with worse patient survival. Thus, an alternative to CD56 as a marker of CD56^bright NK cells was sought. The activation receptor KLRF1 was significantly increased on CD56^bright but not on CD56^dim NK cells. Intratumoral KLRF1⁺ NK cells were more activated and expressed higher levels of activation molecules compared with KLRF1^- NK cells, analogous to the distinct effector function of NK cells across CD56 expression. High intratumoral KLRF1 was associated with improved recurrence-free survival (hazard ratio [HR] 0.53, p = 0.01), cancer-specific survival (HR 0.47, p = 0.02), and overall survival (HR 0.54, p = 0.02) on multivariable analyses that adjusted for clinical and pathologic variables.

CONCLUSIONS

KLRF1 is a promising prognostic marker in bladder cancer and may guide treatment decisions upon validation.

Newly diagnosed multiple myeloma patients with CD56 expression benefit more from autologous stem cell transplantation

BACKGROUND

Several studies showed that lack of CD56 expression was a poor prognostic factor for patients with newly diagnosed multiple myeloma (NDMM). However, other studies were not able to confirm the prognostic value of CD56 in NDMM. This study aimed to evaluate the prognostic value of CD56 expression for patients with NDMM who received autologous stem cell transplantation (ASCT).

METHODS

We retrospectively analyzed 370 patients with NDMM under 66 years old and the propensity score matching technique was used to reduce the bias between two groups.

RESULTS

CD56 expression was observed in 250 (67.6%) patients, and only half of transplant-eligible patients received ASCT for financial and adverse effects concerns after induction therapy. 54.8% (137/250) CD56 positive patients received ASCT; and 47.5% (57/120) CD56 negative patients received ASCT. Univariate and multivariate analyses showed that ASCT was correlated with longer overall survival (OS) (p < 0.001) and progression-free survival (PFS) (p < 0.001) for CD56 positive patients. However, ASCT had no impact on OS and PFS in univariate and multivariate analysis (p > 0.05). In the propensity score matching analysis, 186 CD56 positive patients were identified, 93 patients had received ASCT and 93 patients had no ASCT. Among 120 CD56 negative patients, 80 patients, 40 in each group, were identified. Among 186 matched CD56 positive patients, patients with ASCT had longer OS (87.6 vs.56.1 months, p = 0.049) and PFS (36.7 vs.30.9 months, p = 0.040). However, ASCT had no impact on OS and PFS for matched CD56 negative patients (p > 0.05).

CONCLUSIONS

These results demonstrated that ASCT may improve OS and PFS of CD56 positive patients and had no impact on survival of CD56 negative patients.

Evaluating the prognostic value of CD56 in pediatric acute myeloid leukemia

BACKGROUND

Many cytogenetic changes and gene mutations are associated with acute myeloid leukemia (AML) survival outcomes. CD56 is related to poor prognosis when expressed in adult AML patients. However, the prognostic value of CD56 in children with AML has rarely been reported. In this research, we aimed to evaluate the prognostic value of CD56 in childhood AML.

METHODS

The present retrospective study included 145 newly diagnosed pediatric patients with de novo AML (excluding AML-M3) in two hospitals between January 2015 and April 2021.

RESULTS

The total median (range) age was 75 (8-176) months, and the median follow-up time was 35 months. No significant difference in the 3-year overall survival rate was noted between the CD56-positive and CD56-negative groups (67.0% vs. 79.3%, P = 0.157) who received chemotherapy. However, among high-risk patients, the CD56-positive group had a worse overall survival rate and event-free survival rate (P < 0.05). Furthermore, among high-risk patients, the CD56-positive group had higher relapse and mortality rates than the CD56-negative group (P < 0.05).

CONCLUSIONS

CD56 represents a potential factor of poor prognosis in specific groups of children with AML and should be considered in the risk stratification of the disease. Given the independent prognostic value of CD56 expression, we should consider integrating this marker with some immunophenotypic or cytogenetic abnormalities for comprehensive analysis.

Distinctive phenotype for HLA-E- versus HLA-A2-restricted memory CD8 αβT cells in the course of HCMV infection discloses features shared with NKG2C+CD57+NK and δ2-γδT cell subsets

The human cytomegalovirus (HCMV) triggers both innate and adaptive immune responses, including protective CD8⁺ αβT cells (CD8T) that contributes to the control of the infection. In addition to CD8T restricted by classical HLA class Ia molecules, HCMV also triggers CD8T recognizing peptides from the HCMV UL40 leader peptide and restricted by HLA-E molecules (HLA-E_UL40 CD8T). This study investigated the frequency, phenotype and functions of HLA-E_UL40 CD8T in comparison to the immunodominant HLA-A2_pp65 CD8T upon acute (primary or secondary infection) or chronic infection in kidney transplant recipients (KTR) and in seropositive (HCMV⁺) healthy volunteer (HV) hosts. The frequency of hosts with detected HLA-E_UL40 CD8T was similar after a primary infection (24%) and during viral latency in HCMV+ HV (26%) and equal to the frequency of HLA-A2_pp65 CD8T cells in both conditions (29%). Both CD8T subsets vary from 0.1% to >30% of total circulating CD8T according to the host. Both HLA-E_UL40 and HLA-A2_pp65 CD8T display a phenotype specific of CD8⁺ TEMRA (CD45RA⁺/CCR7^-) but HLA-E_UL40 CD8T express distinctive level for CD3, CD8 and CD45RA. Tim3, Lag-3, 4-1BB, and to a lesser extend 2B4 are hallmarks for T cell priming post-primary infection while KLRG1 and Tigit are markers for restimulated and long lived HCMV-specific CD8T responses. These cell markers are equally expressed on HLA-E_UL40 and HLA-A2_pp65 CD8T. In contrast, CD56 and PD-1 are cell markers discriminating memory HLA-E- from HLA-A2-restricted CD8T. Long lived HLA-E_UL40 display higher proliferation rate compared to HLA-A2_pp65 CD8T consistent with elevated CD57 expression. Finally, a comparative immunoprofiling indicated that HLA-E_UL40 CD8T, divergent from HLA-A2_pp65 CD8T, share the expression of CD56, CD57, NKG2C, CD158 and the lack of PD-1 with NKG2C⁺CD57+ NK and δ2^-γδT cells induced in response to HCMV and thus defines a common immunopattern for these subsets.

Blastic plasmacytoid dendritic cell neoplasm: A clinicopathological diagnostic dilemma report of three cases with review of literature

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a highly aggressive hematologic neoplasm and classified under acute myeloid leukemia. Here, we describe the clinicopathological features of three cases of BPDCN: two with classical and one uncommon immunophenotype. A-35-year-old female (case 1) presented with complaint of nasal mass and generalized lymphadenopathy. Biopsy from axillary lymph node showed infiltration by cells with scant cytoplasm which were immunopositive for LCA, CD4, CD43, and ALK1. Flowcytometry showed positivity for CD45, CD4, CD33, and CD123 while negative for rest all markers. The other two cases have classical immunophenotype. In clinical practice, nasal mass with lymphadenopathy suggests natural killer T-cell/peripheral T-cell lymphoma. Again immunohistochemical positivity for CD4, CD43, and ALK while negativity for CD3 suggests anaplastic large cell lymphoma. In this case, morphology and extensive bone marrow involvement raise the suspicion. Fowcytometry positivity for HLADR, CD123, and CD33 helps in making diagnosis.

Individual dynamics of uterine natural killer cells in natural and stimulated cycles monitored using a new endometrial dating method

PROBLEM

It is important to evaluate the dynamics of uterine natural killer (uNK) cells in hormone replacement therapy (HRT) cycles, given their potential role in implantation and the common usage of HRT cycles with in vitro fertilization (IVF).

METHOD OF STUDY

A total of 132 subfertile patients were evaluated during the secretory phase of either natural ovulation (OV) or HRT cycles, with two biopsies taken on approximately days 5 and 10 after ovulation/progesterone administration in a single menstrual cycle. Immunohistochemical Personal Endometrial Maturation Analysis (PEMA) was used to better quantify secretory-phase endometrial development, in combination with subsequent evaluation of uNK cell density.

RESULTS

uNK cell density increased rapidly from the early to mid-secretory phase, with mean uNK densities of 113 and 117 per mm² in first biopsies and 315 and 387 per mm² in second biopsies for OV and HRT cycles, respectively. After reassessment of endometrial development with PEMA, the first and second biopsies in HRT and OV cycles were histologically dated to developmental ranges between days 15-20 (first biopsy) and days 19-25 (second biopsy).

CONCLUSION

Subfertile women showed variable endometrial development in PEMA assessment, with uNK cell density correlating with the dating results. Overall, comparable levels of uNK cell density were observed in OV and HRT cycles. Importantly, uNK cell density depends on the histological maturation stage, with similar low coefficients of determination. This observation suggests that aberrant uNK cell results more likely reflect displaced endometrial maturation, rather than an intrinsic anomaly in uNK cell trafficking.

An unusual case of hepatosplenic T-cell lymphoma-like unclassifiable T/NK-cell lymphoma accompanied by acute myeloid leukemia

We describe a case of unclassifiable T/NK-cell lymphoma with concomitant acute myeloid leukemia (AML). A 73-year-old Japanese man was diagnosed with AML by bone marrow smear, but the presence of splenomegaly and liver tumor was incompatible with AML. Splenectomy and hepatic resection were performed to resolve the thrombocytopenia and define the diagnosis. The pathological findings showed sinusoidal involvement of abnormal lymphoid cells that were CD3-positive but negative for T-cell receptor (TCR) rearrangement. Our case could not be categorized as hepatosplenic T-cell lymphoma because of the lack of immunohistological expression of TCR, despite the clinical similarity.

The Effect of Heat Shock on Myogenic Differentiation of Human Skeletal-Muscle-Derived Mesenchymal Stem/Stromal Cells

Muscle injuries, degenerative diseases and other lesions negatively affect functioning of human skeletomuscular system and thus quality of life. Therefore, the investigation of molecular mechanisms, stimulating myogenic differentiation of primary skeletal-muscle-derived mesenchymal stem/stromal cells (SM-MSCs), is actual and needed. The aim of the present study was to investigate the myogenic differentiation of CD56 (neural cell adhesion molecule, NCAM)-positive and -negative SM-MSCs and their response to the non-cytotoxic heat stimulus. The SM-MSCs were isolated from the post operation muscle tissue, sorted by flow cytometer according to the CD56 biomarker and morphology, surface profile, proliferation and myogenic differentiation has been investigated. Data show that CD56(+) cells were smaller in size, better proliferated and had significantly higher levels of CD146 (MCAM) and CD318 (CDCP1) compared with the CD56(-) cells. At control level, CD56(+) cells significantly more expressed myogenic differentiation markers MYOD1 and myogenin (MYOG) and better differentiated to the myogenic direction. The non-cytotoxic heat stimulus significantly stronger stimulated expression of myogenic markers in CD56(+) than in CD56(-) cells that correlated with the multinucleated cell formation. Data show that regenerative properties of CD56(+) SM-MSCs can be stimulated by an extracellular stimulus and be used as a promising skeletal muscle regenerating tool in vivo.

Extramedullary Multiple Myeloma: A Patient-Focused Review of the Pathogenesis of Bone Marrow Escape

Multiple myeloma (MM) is a neoplastic clonal proliferation of plasma cells, predominantly in the bone marrow. The presentation of MM in extramedullary tissue, particularly the liver, is uncommon with only a few reported cases in literature. We report a rare and unusual presentation of kappa light chain restricted MM with progression of disease to involve the liver. MM was initially diagnosed on bone marrow biopsy, initially treated with carfilzomib, lenalidomide and dexamethasone, later changed to bortezomib, daratumumab and dexamethasone. There was subsequent progression with a new biopsy-proven myelomatous liver lesion. The patient could not receive high-dose chemotherapy due to multiple co-morbidities and extent of disease and eventually succumbed to her disease rapidly. This article emphasizes the poor prognosis of extramedullary involvement in MM and the pathogenic mechanisms by which it develops. Based on a review of the literature of other cases and case series of solitary or diffuse myeloma involvement in the liver, high-dose chemotherapy in combination with proteasome inhibitors and immunomodulators has the best success rate with less relapse and progressive disease in extramedullary myeloma. Our analysis concluded that the gain of CD44, loss of CD56, loss of very late antigen-4 (VLA-4), imbalance of the chemokine receptor-4-chemokine ligand-12 (CXCR4-CXCL12) axis, metastasis-associated lung adenocarcinoma 1 (MALAT1) upregulation, RAS pathway activation as well as 13q and 17p deletions show an increased propensity of malignant plasma cells to leave the bone marrow and hone in extramedullary sites giving rise to more aggressive extramedullary diseases. Targeted therapeutics such as CD44v-directed therapy and reactivation of p53 to wild-type conformation could potentially be evaluated as treatment options in the future to improve outcomes in this aggressive form of MM, especially in patients with advanced disease and limited treatment options.

Residual Bone Marrow T & NK-Cells at Diagnosis in Pediatric Pre-B-ALL: A Case-Control Study

Background

Mature bone marrow T lymphocytes and NK may have a special relevance in the control of the malignant growth.

Objective

We aimed to assess the percentage of the residual BM T-cells, (T-helper -T-cytotoxic- NKT) and the NK cells of childhood precursor B-lymphoblastic leukemia (B-ALL) as an indicator of innate and adaptive immunity in these patients.

Subjects and Methods

This study was conducted on 40 B-ALL patients, and 40 apparently healthy matched children served as a control group. The flow cytometry was used to assess the percentage of the residual BM T-cells (T-helper, T-cytotoxic and NKT), and the NK cells.

Results

Compared with the control group, the percentage of the residual BM T-cells, its subtypes (T-helper, T-cytotoxic), and NKT cells in addition to the NK cells was significantly decreased in Group IA, and Group IB, but there was no significant difference between Group IA and Group IB in all studied parameters. In terms of the CD4/CD8 ratio, there was a significant increase in Group IA as compared to the control group (P < 0.026), but there were no significant statistical differences in CD4/CD8 ratio between Groups IB, and the control. Likewise, in CD4/CD8 ratio between groups IA, and Groups IB (P > 0.05). The percentage of NK, and NKT cells shows a significant increase in Hepatomegaly and Splenomegaly, as compared to non-Hepatomegaly and non-Splenomegaly patients of Groups IB (P < 0.05). However, there was a significant increase in statistical differences in the percentage of NKT cell between non-Splenomegaly, as compared to Splenomegaly patients of Group IA (P < 0.05). Additionally, there is a negative correlation between B.M Blast% to CD4/CD8 ratio and NK%, but there is no significant correlation between B.M Blast% to NK T% in the group 1 A.

Describing IgA Myeloma: An Immunophenotypic and Molecular Approach

Plasma cell myeloma (PCM) is defined as a clonal disease of terminally differentiated plasma cells that secrete immunoglobulin. The biologic underpinnings of IgA-type multiple myeloma's (IgAMM) aggressive nature, including its increased morbidity and mortality, have not been elucidated. We describe the clinical, phenotypic, and cytogenetic characteristics of IgA-MM. Flow-cytometry analysis was performed to phenotype clonal plasma cell populations, and interface with fluorescent in situ hybridization (iFISH) to exploit cytogenetics to determine risk stratification; 68.1% of cases were of intermediate or high risk. On flow cytometry, samples from our IgA-PCM cohort revealed less frequent CD56 expression when compared to samples with other PCM subtypes. Our study demonstrated lower frequency of CD56 expression (52.8%). We hypothesize that loss of CD56 may play a significant role in the aggressive behavior of IgA-PCM due to the loss of cell-to-cell adhesion resulting in a higher propensity for extramedullary presentation.

Human NK cells responses are enhanced by CD56 engagement

Natural Killer (NK) cells are important innate lymphocytes for effective immune responses against intracellular pathogens and tumors. CD56 is a well-known marker for human NK cells, but there is very limited information about a functional role of this surface receptor. Here we show that engagement of CD56 can induce NK cell activation resulting in degranulation, IFN-γ secretion and morphological changes, making CD56 a potential co-activating receptor in NK cells. Interestingly, this effect was only observed in cytokine pre-activated and not in freshly isolated human NK cells, demonstrating that NK cell reactivity upon CD56 engagement was dependent on cytokine stimulation. Inhibition of Syk, PI3K, Erk and src-family-kinases impaired CD56-mediated NK cell stimulation. Finally, we used CRISPR/Cas9 to delete CD56 from primary human NK cells. While this abolished the stimulatory effect of CD56 on pre-activated NK cells, the cytotoxic activity of NK cells against several tumor target cells was not affected by the absence of CD56. This demonstrates that the stimulating effect of CD56 on pre-activated NK cells does not have a major impact on their cytotoxic activity, but it may contribute to the function of CD56 as a fungal recognition receptor and in the NK cell developmental synapse. This article is protected by copyright. All rights reserved.

Skeletal Muscle Satellite Cells in Sickle Cell Disease Patients and Their Responses to a Moderate-intensity Endurance Exercise Training Program

We previously demonstrated that 8 weeks of moderate-intensity endurance training is safe and improves muscle function and characteristics of sickle cell disease (SCD) patients. Here, we investigated skeletal muscle satellite cells (SCs) in SCD patients and their responses to a training program. Fifteen patients followed the training program while 18 control patients maintained a normal lifestyle. Biopsies of the vastus lateralis muscle were performed before and after training. After training, the cross-sectional area and myonuclear content in type I fibers were slightly increased in the training patients compared to non-training patients. The SC pool was unchanged in type I fibers while it was slightly decreased in type II fibers in the training patients compared to non-training patients. No necrotic fibers were detected in patients before or after training. Therefore, the slight myonuclear accretion in type I fibers in trained SCD patients may highlight the contribution of SCs to training-induced slight type I fiber hypertrophy without expansion of the SC pool. The low training intensity and the short duration of training sessions could explain the low SC response to the training program. However, the lack of necrotic fibers suggests that the training program seemed to be safe for patients' muscle tissue.

Natural killer cell detection, quantification, and subpopulation identification on paper microfluidic cell chromatography using smartphone-based machine learning classification

Natural killer (NK) cells are immune cells that defend against viral infections and cancer and are used in cancer immunotherapies. Subpopulations of NK cells include CD56^dim and CD56^bright which either produce cytokines or cytotoxically kill cells directly. The absolute number and proportion of these cells in peripheral blood are tied to proper immune function. Current methods of cytokine detection and proportion of NK cell subpopulations require fluorescent dyes and highly specialized equipment, e.g., flow cytometry, thus rapid cell quantification and subpopulation analysis are needed in the clinical setting. Here, a smartphone-based device and a two-component paper microfluidic chip were used towards identifying NK cell subpopulation and inflammatory markers. One unit measured flow velocity via smartphone-captured video, determining cytokine (IL-2) and total NK cell concentrations in undiluted buffy coat blood samples. The other, single flow lane unit performs spatial separation of CD56^dim and CD56^bright and cells over its length using differential binding of anti-CD56 nanoparticles. A smartphone microscope combined with cloud-based machine learning predictive modeling (utilizing a random forest classification algorithm) analyzed both flow data and NK cell subpopulation differentiation. Limits of detection for cytokine and cell concentrations were 98 IU/mL and 68 cells/mL, respectively, and cell subpopulation analysis showed 89% accuracy.

Pro- and Anti-Inflammatory Cytokines in the Context of NK Cell-Trophoblast Interactions

During pregnancy, uterine NK cells interact with trophoblast cells. In addition to contact interactions, uterine NK cells are influenced by cytokines, which are secreted by the cells of the decidua microenvironment. Cytokines can affect the phenotypic characteristics of NK cells and change their functional activity. An imbalance of pro- and anti-inflammatory signals can lead to the development of reproductive pathology. The aim of this study was to assess the effects of cytokines on NK cells in the presence of trophoblast cells in an in vitro model. We used TNFα, IFNγ, TGFβ and IL-10; the NK-92 cell line; and peripheral blood NK cells (pNKs) from healthy, non-pregnant women. For trophoblast cells, the JEG-3 cell line was used. In the monoculture of NK-92 cells, TNFα caused a decrease in CD56 expression. In the coculture of NK cells with JEG-3 cells, TNFα increased the expression of NKG2C and NKG2A by NK-92 cells. Under the influence of TGFβ, the expression of CD56 increased and the expression of NKp30 decreased in the monoculture. After the preliminary cultivation of NK-92 cells in the presence of TGFβ, their cytotoxicity increased. In the case of adding TGFβ to the PBMC culture, as well as coculturing PBMCs and JEG-3 cells, the expression of CD56 and NKp44 by pNK cells was reduced. The differences in the effects of TGFβ in the model using NK-92 cells and pNK cells may be associated with the possible influence of monocytes or other lymphoid cells from the mononuclear fraction.

Expression of CD56 is Not Limited to Biliary Atresia and Correlates with the Degree of Fibrosis in Pediatric Cholestatic Diseases

BACKGROUNDS AND AIMS

CD56 immunostain is used as an adjunct to aid in the preoperative diagnosis of biliary atresia (BA) by liver biopsy. We aimed to study the expression of CD56 in different pediatric cholestatic diseases thereby evaluating its utility in the diagnosis of BA.

METHODS

We performed immunohistochemistry for CD56 on 35 cases of pediatric cholestatic diseases and five age-matched controls. CD56 expression was assessed by a multiplication score (percentage positivity x intensity) in the biliary epithelium.

RESULTS

The multiplication score between BA and choledochal cyst was not significantly different. High scores were also encountered in other cholestatic disorders. The score showed a significant negative association with serum albumin and a significant positive correlation with the serum ALT level. Very significant positive correlation between the score and portal fibrosis was obtained.

CONCLUSION

CD56 expression is an infidel marker for the histological diagnosis of BA and rather provides a clue to the disease status in pediatric cholestatic diseases.

Corrigendum: Gamma/Delta T Cells in the Course of Healthy Human Pregnancy: Cytotoxic Potential and the Tendency of CD8 Expression Make CD56+ γδT Cells a Unique Lymphocyte Subset

[This corrects the article DOI: 10.3389/fimmu.2020.596489.].

Epstein-Barr Virus-Positive Langerhans Cell Sarcoma: Is There a Link? A Case Report

Langerhans cell sarcoma (LCS) is an extremely rare, malignant neoplasm that originates from Langerhans cells (LCs). Fewer than 70 cases have been reported in the English-language literature. LCS typically involves multiple organs, including the skin, lymph nodes, lungs, bone, bone marrow, liver, spleen, and soft tissues. Several etiological factors for LCS have been proposed, including immunosuppression, virus infection, and prior hematological disease. We report a rare case of LCS with Epstein-Barr virus (EBV) infection; bilateral cervical giant cysts were the initial manifestation. To our knowledge, this is the first report of LCS with EBV infection. The case information was complete, and the relevant literature was reviewed to gain insight into LCS. The case raises new questions on the oncogenic character of EBV.

Outcomes of stem cell mobilization and engraftment in patients with multiple myeloma according to CD56 expression status

BACKGROUND

The molecular mechanism underlying the mobilization and engraftment of CD34+ cells is poorly understood. The most relevant factors in the regulation of stem cell release and engraftment include chemokines, adhesion molecules, and chemokine receptors. Previously, it was suggested that the absence of CD56 expression could be used as a predictive factor for mobilization failure at the time of diagnosis. Here, we investigated the effect of CD56 expression status on both mobilization and engraftment processes. Additionally, other factors affecting mobilization and engraftment efficacy were investigated.

METHODS

Data from 79 multiple myeloma patients undergoing autologous stem cell transplantation between 2015 and 2020 were analyzed for peripheral stem cell mobilization and posttransplant neutrophil and platelet engraftment according to CD56 expression on myeloma cells.

RESULTS

No difference in either the median number of CD34+ cells collected or time to engraftment was found between the CD56+ and CD56- groups. The age of the patients (p = 0.025) and peak number of circulating CD34+ cells in peripheral blood (p = 0.005) were important predictors for a higher number of collected CD34+ cells. The average time to recovery of leukocytes and platelets after transplantation was markedly correlated with the number of transplanted stem cells and peak number of circulating CD34+ cells in peripheral blood, respectively (p = 0.049 and p = 0.003).

CONCLUSIONS

Our results indicated no effect of CD56 expression status on the mobilization and engraftment of PBSCs. Our results also support the notion that the peak number of circulating CD34+ cells in peripheral blood is clinically important for rapid platelet engraftment following HPC transplantation.

Gamma-ray irradiation modulates PGRMC1 expression and the number of CD56+ and FoxP3+ cells in the tumor microenvironment of endometrial endometrioid adenocarcinoma

Purpose

Although the conventional gamma ray brachytherapy has been successful in treating endometrioid endometrial adenocarcinoma (EC), the molecular and cellular mechanisms of this anti-tumorigenic response remain unclear. Therefore, we investigated whether gamma ray irradiation induces changes in the number of FoxP3⁺ T-regulatory lymphocytes (Tregs), CD56⁺ natural killer cells (NK), and the expression of progesterone receptor membrane component 1 (PGRMC1) in the tumor microenvironment (TME).

Materials and Methods

According to the inclusion criteria, 127 cases were selected and grouped into irradiation-treated (Rad⁺) and control (underwent surgery) groups and analyzed using immunohistochemistry. Predictive prognostic values were analyzed using Mann-Whitney U test, ROC analysis, relative risk, log-rank, Spearman rank tests and multivariate Cox’s regression.

Results

We observed significant differences (p < 0.001) between the radiation-treated patients and the control groups in FoxP3⁺ Tregs numbers, CD56⁺ NK cells and PGRMC1 expression. Gamma ray induced a 3.71- and 3.39-fold increase in the infiltration of FoxP3⁺ cells, CD56⁺ NK cells, respectively and 0.0034-fold change in PGRMC1 expression. Univariate and multivariate analyses revealed predictive role of the parameters. In the irradiated patients’ group, inverted correlations between clinical unfavorable outcome, FoxP3⁺ Tregs and CD56⁺ NK cells were observed.

Conclusion

Our results suggest an immune-modulating role, specifically by increasing immune cell infiltration, of gamma radiation in the TME which may potentially be utilized as biomarkers in prognostic values.

Infections, Reactions of Natural Killer T Cells and Natural Killer Cells, and Kidney Injury

Natural killer T (NKT) cells and NK cells are representative innate immune cells that perform antitumor and antimicrobial functions. The involvement of these cells in various renal diseases, including acute kidney injury (AKI), has recently become evident. Murine NKT cells are activated and cause AKI in response to various stimuli, such as their specific ligand, cytokines, and bacterial components. Both renal vascular endothelial cell injury (via the perforin-mediated pathway) and tubular epithelial cell injury (via the tumor necrosis factor-alpha/Fas ligand pathway) are independently involved in the pathogenesis of AKI. NK cells complement the functions of NKT cells, thereby contributing to the development of infection-associated AKI. Human CD56⁺ T cells, which are a functional counterpart of murine NKT cells, as well as a subpopulation of CD56⁺ NK cells, strongly damage intrinsic renal cells in vitro upon their activation, possibly through mechanisms similar to those in mice. These cells are also thought to be involved in the acute exacerbation of pre-existing glomerulonephritis triggered by infection in humans, and their roles in sepsis-associated AKI are currently under investigation. In this review, we will provide an overview of the recent advances in the understanding of the association among infections, NKT and NK cells, and kidney injury, which is much more profound than previously considered. The important role of liver macrophages in the activation of NKT cells will also be introduced.

Role of NK Cells in Tumor Progression

Natural Killer (NK) cells are effector lymphocytes with the ability to generate an antitumor response. NK cells encompass a diverse group of subsets with different properties and have the capacity to kill cancer cells by different means. However, tumor cells have developed several mechanisms to evade NK cell-mediated killing. In this chapter, we summarize some aspects of NK cell biology with the aim to understand the competence of these cells and explore some of the challenges that NK cells have to face in different malignancies. Moreover, we will review the current knowledge about the role of NK cells in tumor progression and describe their phenotype and effector functions in tumor tissues and peripheral blood from cancer patients. Finally, we will recapitulate several findings from different studies focused on determining the prognostic value of NK cells in distinct cancers.

Kidney infiltrating NK cells and NK-like T-cells in lupus nephritis: presence, localization, and the effect of immunosuppressive treatment

Systemic lupus erythematosus (SLE) is a multi-organ inflammatory disease with kidney inflammation, lupus nephritis (LN), being one of the most severe manifestations. Immune complex deposits, particularly in glomeruli, and T cells, B cells, and myeloid cells, mainly with extraglomerular localization, contribute to the inflammatory process. Natural killer (NK) cells have been suggested to play a role in autoimmune diseases, but have not been investigated in detail in renal lupus before. In this exploratory study, we performed the first characterization of NK cell number and distribution in LN kidney biopsies. Twelve SLE patients were analyzed in the active phase of disease and five patients following immunosuppressive therapy. CD56+ cells, corresponding to NK cells or NK-like T-cells, were identified in all patients; however, with reduced numbers in four out of five patients at follow-up. Furthermore, cells were present in the kidney interstitium and peri-glomerular areas, but only rarely in glomeruli. Fluorescent co-staining of CD56 or NKp46 and CD3 revealed the presence of both CD56+/NKp46+CD3-NK cells and CD56+/NKp46+CD3+NK-like T-cells. Compared to healthy kidney sections, one out of four LN patients showed increased numbers of NK cells. A correlation between CD56+ and NK cells with clinical parameters could not be observed, perhaps due to the small patient cohort. In conclusion, we have identified NK cells and NK-like T-cells in the LN kidney and performed the first detailed analysis of their localization during active and inactive diseases. Their role in LN pathogenesis is, however, unclear and deserves further studies.

Post-Transplant Nivolumab Plus Unselected Autologous Lymphocytes in Refractory Hodgkin Lymphoma: A Feasible and Promising Salvage Therapy Associated With Expansion and Maturation of NK Cells

Immune checkpoint inhibitors (CI) have demonstrated clinical activity in Hodgkin Lymphoma (HL) patients relapsing after autologous stem cell transplantation (ASCT), although only 20% complete response (CR) rate was observed. The efficacy of CI is strictly related to the host immune competence, which is impaired in heavily pre-treated HL patients. Here, we aimed to enhance the activity of early post-ASCT CI (nivolumab) administration with the infusion of autologous lymphocytes (ALI). Twelve patients with relapse/refractory (R/R) HL (median age 28.5 years; range 18-65), underwent lymphocyte apheresis after first line chemotherapy and then proceeded to salvage therapy. Subsequently, 9 patients with progressive disease at ASCT received early post-transplant CI supported with four ALI, whereas 3 responding patients received ALI alone, as a control cohort. No severe adverse events were recorded. HL-treated patients achieved negative PET scan CR and 8 are alive and disease-free after a median follow-up of 28 months. Four patients underwent subsequent allogeneic SCT. Phenotypic analysis of circulating cells showed a faster expansion of highly differentiated NK cells in ALI plus nivolumab-treated patients as compared to control patients. Our data show anti-tumor activity with good tolerability of ALI + CI for R/R HL and suggest that this setting may accelerate NK cell development/maturation and favor the expansion of the “adaptive” NK cell compartment in patients with HCMV seropositivity, in the absence of HCMV reactivation.

A case of papillary hyperplasia of thyroid misdiagnosed as papillary thyroid carcinoma: Case report and review of literature

Overdiagnosis of papillary thyroid hyperplasia which may mimic papillary thyroid carcinoma in fine-needle aspiration and frozen section has a serious impact on the patient. Therefore, it is important to know the difference between them to avoid over or undertreatment.

Corrigendum: Efficacy of Intrauterine Perfusion of Cyclosporin A for Intractable Recurrent Spontaneous Abortion Patients With Endometrial Alloimmune Disorders: A Randomized Controlled Trial

[This corrects the article DOI: 10.3389/fphys.2021.737878.].