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Interleukin-21 является критически важным цитокином для формирования клеток долгоживущей плазмы с конкретным вирусом.

Долгоживущие плазменные клетки, которые живут в костном мозге, формируют антитела в отсутствие антигена и являются клеточной основой длительного юморального иммунитета. Формирование этих долгоживущих плазменных клеток зависит от ряда высокоорганизованных взаимодействий между антигенно специфическими CD4 T и B клетками, а также от формирования микробных центров (ГЦ). В этом исследовании мы изучили роль цитокина интерлейкина-21 (IL-21) в регулировании юморального иммунитета при острых вирусных инфекциях. Используя мыши IL-21-дефицит-рецептора (IL-21R(-/-)), мы обнаружили, что конкретно по вирусу

Совпадение в аннотации оригинала
Long-lived plasma cells that reside in the bone marrow constitutively produce antibody in the absence of antigen and are the cellular basis of durable humoral immunity. The generation of these long-lived plasma cells depends upon a series of highly orchestrated interactions between antigen-specific CD4 T cells and B cells and the formation of germinal center…

Increased IgG4-Positive Plasma Cells in Granulomatosis with Polyangiitis: A Diagnostic Pitfall of IgG4-Related Disease.

Granulomatosis with polyangiitis (Wegener's) (GPA) may mimic IgG4-related disease (IgG4-RD) on histologic examination of some biopsies, especially those from head and neck sites. IgG4 immunostain is often performed in this context for differential diagnosis with IgG4-RD. However, the prevalence of IgG4+ cells in GPA has not been explored. We examined the IgG4+ cells in 26 cases confirmed as GPA by a thorough clinical and pathologic assessment. Twenty-six biopsies consisted of 14 sinonasal/oral cavity/nasopharynx, 7 orbit/periorbital, 3 lung/pleura, 1 iliac fossa/kidney, and 1 dura specimens. E

Increased number of circulating endothelial cells and plasma markers of endothelial damage in chronic cocaine users.

BACKGROUND: Cocaine use has been related with the development of accelerated atherosclerosis and with an increased risk of cardiac and cerebrovascular events, such as myocardial infarction, sudden cardiac death, and ischemic stroke. The underlying mechanisms leading to these complications are not fully understood, although thrombus formation and altered vascular function are prominent findings. OBJECTIVES: Our aim was to evaluate markers of endothelial dysfunction in chronic cocaine consumers before and after drug withdrawal. PATIENTS/METHODS: We determined circulating endothelial cells (CEC

Maintenance of long-term immunological memory by Ig+CD45R+ non-plasma B cells following mucosal immunizations.

To determine whether long-term immunological B cell memory following mucosal vaccinations is maintained by terminally differentiated Ig-CD45R- plasma cells or Ig+CD45R+ B cells, we immunized mice orally with the non-toxic B subunit of cholera toxin (CTB) as a carrier protein haptenated with FITC (CTB-FITC) plus CT adjuvant. We found that the adoptive transfer of Ig+CD45R+ but not the Ig-CD45R- cells, resulted in higher numbers of FITC-specific IgA-secreting cells in the intestine as well as higher anti-FITC serum IgA titers, suggesting that long term B cell immunological memory following oral …

Idiopathic fibroinflammatory disease of the face, eyelids, and periorbital membrane with immunoglobulin G4-positive plasma cells.

Progressive sclerosing orbital pseudotumors are a subset of usually primary and localized idiopathic fibroinflammatory disorders. We report on a 66-year-old man who developed this condition along the facial tissue planes with extension into the orbit and preferential involvement of the periorbital membrane. Fibrocollagenous tissue with scattered lymphoid aggregates without follicle formation dominated the process. There was a light dispersion of B and T lymphocytes and histiocytes in the stroma. Immunoglobulin G4 (IgG4)-positive plasma cells (>35 per high-power field) were identified mostly in…

Serglycin constitutively secreted by myeloma plasma cells is a potent inhibitor of bone mineralization in vitro.

Although the biological significance of proteoglycans (PGs) has previously been highlighted in multiple myeloma (MM), little is known about … ical staining of bone marrow biopsies showed the presence of serglycin both in benign and malignant plasma cells. Immunoblotting in bone marrow aspirates from a limited number of patients with newly diagnosed MM revealed highly increased levels of serglycin in 30% of the cases. Serglycin isolated from myeloma plasma cells was found to influence the bone minera …

Description of B lymphocytes and plasma cells, complement, and chemokines/receptors in acute liver allograft rejection.

BACKGROUND: Although antibody mechanisms play a pathogenetic role in liver allograft rejection, no data exist on B lymphocytes, plasma cells, complement, and chemokines in rejected liver tissue. METHODS: Liver biopsy specimens from 25 patients with acute allograft rejection (AR) (rejection activity index, RAI score: 1-9) were analyzed by immunohistochemistry (IH) and reverse transcriptase-polymerase chain reaction (RT-PCR) and compared with biopsy specimens taken prior to implantation (PI). The number of CD20 and CD138 cells was evaluated, and the presence and abundance of the chemokines macr…

Interstitial nephritis with infiltration of IgG-kappa positive plasma cells in a patient with Sjögren's syndrome.

OBJECTIVES: To determine the prevalence of May-Thurner syndrome (MTS) in left lower limb deep venous thrombosis (DVT) cases and to analyze the outcome of endovascular intervention in these patients. METHODS: A record-based descriptive study was carried out in Radiology Department, King Fahad Military Medical Complex, Dhahran, Saudi Arabia, including patients who underwent lower limb duplex ultrasounds between January 2015-2021. Patients with bilateral DVTs, known pelvic masses, and pelvic surgeries were excluded. All patients positive for DVTs were identified and further imaging was reviewed.

Impaired osteoblastogenesis in myeloma bone disease: role of upregulated apoptosis by cytokines and malignant plasma cells.

Bone remodelling is severely affected in myeloma bone disease as a consequence of skeletal metastatization of malignant plasma cells. We investigated whether defective bone replacement is dependent on increased osteoblast apoptosis and/or on deregulated events within the bone microenvironment. Circulating tumour necrosis factor (TNF)-alpha, interferon-gamma, interleukin (IL)-1beta, and IL-6 levels were higher in myeloma patients with overt bone disease, whose osteoblasts constitutively overexpressed Fas, DR4/DR5 complex as receptors to TNF-related apoptosis inducing ligand, intercellular adhes…

p16(INK4a) and p15(INK4b) gene methylations in plasma cells from monoclonal gammopathy of undetermined significance.

p15(INK4b) and p16(INK4a) proteins are cell cycle regulators involved in the inhibition of G1 phase progression. High frequency of methylation of both genes has been reported in multiple myeloma (MM), but it remains to be determined how and when these alterations contribute to tumorigenesis. Monoclonal gammopathy of undetermined significance (MGUS) represents an early disease stage in a fraction of MMs. Plasma cells from 33 patients with MGUS and 33 patients with MM were isolated and analyzed for p15(INK4b) and p16(INK4a) methylation by methylation-specific polymerase chain reaction. Selective…

Fish demonstrates treatment-related chromosome damage in myeloid but not plasma cells in primary systemic amyloidosis.

Conventional cytogenetic analysis is limited in the evaluation of plasma cell disorders because, relative to normal hematopoietic elements, plasma cells divide slowly. Moreover, it is difficult to know whether abnormal metaphases originate from malignant plasma cells or myeloid cells harboring other abnormalities. We studied a patient with primary systemic amyloidosis who had previously been treated with an alkylating agent. Bone marrow cells were analyzed by cytoplasmic-immunoglobulin fluorescent staining combined with fluorescent in situ hybridization (cIg-FISH). Both chromosome enumeration …

Monoclonal gammopathy of undetermined significance: chromosome changes are a common finding within bone marrow plasma cells.

We used two indirect approaches [image analysis (Feulgen staining) and fluorescence in situ hybridization (FISH)] to study bone marrow plasma cells (BMPC) in 28 patients fulfilling criteria for MGUS. 61% of patients were found to be aneuploid after image analysis: three were hypodiploid and 14 were hyperdiploid. 12/14 hyperdiploid patients also revealed abnormalities after FISH: 12-72% of BMPC exhibited trisomy for at least one of chromosomes 3, 7, 9 and 11. These latter chromosomes are the four chromosomes most frequently implicated (in the shape of trisomy) in MM, confirming the tight relati…

Increased plasma levels of nerve growth factor in vernal keratoconjunctivitis and relationship to conjunctival mast cells.

PURPOSE: To evaluate the nerve growth factor (NGF) plasma concentration in patients with vernal keratoconjunctivitis and to correlate it with the histopathology and immunopathology of the disease. METHODS: An immunoenzymatic assay was performed to measure NGF plasma levels in patients with vernal keratoconjunctivitis and in healthy matched controls. A competitive radioimmunoassay was used to detect eosinophil cationic protein (ECP) and total specific immunoglobulin E (IgE) serum levels. Histologic evaluation was performed in tarsal and bulbar conjunctival biopsies. RESULTS: Plasma levels of

Plasma membrane and intracellular pools of transferrin receptors decline during in vitro cultivation of U937 cells.

Transferrin receptor expression in the monocyte-like cell line U937 was investigated during in vitro cultivation. U937 cells expressed a single class of high affinity surface transferrin receptors (KD approximately 4 nM), with apparent subunit Mr of 90-95,000 Da as determined by SDS-reducing PAGE. [125I]-transferrin binding studies on detergent-solubilized cells revealed that half to two-thirds of the total functional binding sites were located intracellularly. Radioligand binding, immunofluorescence and flow cytometry studies were performed on intact, detergent-solubilized, or saponin-permeab

Surface antigen expression of human neoplastic plasma cells includes molecules associated with lymphocyte recirculation and adhesion.

The surface phenotype of neoplastic plasma cells from peripheral blood of plasma cell leukaemia patients and bone marrow of patients with myelomatosis was investigated with two monoclonal antibody panels including 50 selected from the B cell panel of the IVth International Workshop on Leucocyte Differentiation Antigens. The majority of myelomas expressed CD24 (HB8 epitope only), CD38, CD44, CD54, and the antigen recognized by the monoclonal antibody 8A. A range of other antigens may also be expressed including CD10, CD32 (FcR II), CD19, CD20 and MHC Class II. Antigens expressed by myeloma plas…

IgG and IgA subclass distribution of total immunoglobulin and rheumatoid factors in rheumatoid tissue plasma cells.

The subclass distribution of IgG and IgA plasma cells, and in IgG and IgA rheumatoid factor (RF) producing cells was studied in sections of synovial tissue from seropositive RA and various types of seronegative arthritis, including ankylosing spondylitis, psoriatic arthritis, and Reiter's syndrome. The study was performed with immunofluorescence technique and monoclonal IgG and IgA subclass specific antibodies. IgG RF producing cells were identified by their ability to bind and activate factors both in the early (C3) and late (C5b-9) part of the complement cascade. IgA RF cells were identified…

Gene deletions force nonsecretory alpha-chain disease plasma cells to produce membrane-form alpha-chain only.

We studied a case of nonsecretory alpha-chain disease. The proliferating plasma cells contained a short transcript coding for a truncated membrane-form alpha 1-chain. The productive alpha-gene bore several noncontiguous deletions affecting the VHDJH and CH1 regions. Two deletions were accompanied with peculiar insertions containing duplications. The first insertion contained an acceptor splice site and was present in part in the mature transcript, thus coding for an abnormal aminoterminal peptide. Another deletion located 3' to CH3 eliminated the polyadenylation site of secreted-form alpha-mRN…

[The nature of crystals in plasma cells present in a case of apparently benign biclonal gammapathy].

A 77 years old white man presents, in his blood serum, a moderate gammapathy with 2 monoclonal peaks, IgAk and IgGlambda, and in his urine a little quantity of BJk, without any clinical or radiological manifestation. The sternal bone marrow showed 3-5% plasmacells, mostly containing many needlelike inclusions in the cytoplasm. These inclusions, red-violet at the May-Grünwald-Giemsa, were PAS and Sudan negative; positive at the Danielli reaction (for proteins). The alpha-naphtil-acetate-esterase and the acid phosphatase were present in one outer layer of the inclusions; ATP-ase was absent. At t

[Some experimental evidences for immune functions of interstitial plasma-cells of the submaxillary glands (author's transl)].

Interstitial plasma-like cells, constantly present in the submaxillary glands, are they endocrine cells or true plasma-cells? They do not show any change in case of hypertrophy of the salivary glands which is observed under isoproterenol repeated administration. In contrary their number increase greatly during the immunologic stimulation by human albumin injections in the Hamster cheek pouches. So, it does appear that they would be true plasma cells involved in immunoglobulins synthesis.

Nef and Vpu protect infected cells from ADCP mediated by plasma from people with HIV-1.

The HIV-1 envelope glycoprotein (Env) represents the only viral antigen at the surface of infected cells, making it an ideal target for antibody-based therapies. Most antibodies elicited in people with HIV (PWH) do not recognize Env in its native "closed" conformation but readily bind to Env when it samples the CD4-bound "open" conformation. Downregulation of CD4 at the surface of infected cells by the viral accessory proteins Nef and Vpu prevents the premature opening of Env and has been shown to protect infected cells from antibody-dependent cellular cytotoxicity (ADCC) mediated by PWH plasm