Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 3 de 3
Int Immunopharmacol ; 101(Pt A): 108292, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1487772


Leukopenia is a common manifestation of many diseases, including global outbreak SAS-CoV-2 infection. Granulocyte-macrophage colony-stimulating factor (GM -CSF) has been proved to be effective in promoting lymphocyte regeneration, but adverse immunological effects have also emerged. This study aim to investigate the effect of GM -CSF on BCR heavy chain CDR3 repertoire while promoting lymphocyte regeneration. Cyclophosphamide (CTX) and GM -CSF were used to inhibit and stimulate bone marrow hematopoiesis, respectively. High throughput sequencing was applied to detect the characteristics of BCR CDR3 repertoire in controls, CTX group and GM -CSF group. The white blood cells (WBCs) were quickly reduced (P < 0.05) with lymphocytes decreasing causing by CTX, and the WBCs and lymphocytes returned to the level of controls after GM -CSF treatment. The diversity of BCR heavy chain CDR3 repertoire was also significantly decreased in CTX group. Although there is still a big gap from the controls, the diversity was picked up after GM -CSF treatment. The expression of IGHD01-01, IGHD02-14 and IGHJ04-01 with high-frequency usage regularly and significantly changed in three groups, and many genes with low-frequency usage lost in CTX group and did not reappear in GM -CSF group. Moreover, two shared sequences and accounted for the highest proportion in GM -CSF group have been detected in animal model of chronic lymphocytic leukemia. These results revealed that GM -CSF can partially restore changes in the BCR heavy chain CDR3 repertoire while promoting lymphocyte regeneration, but it may also lead to rearrangement, proliferation and activation of abnormal B cells, which can provide a basis for further study on the adverse immunological effects and mechanism of GM -CSF treatment.

Cyclophosphamide/adverse effects , Granulocyte-Macrophage Colony-Stimulating Factor/immunology , Leukopenia/immunology , Lymphocytes/drug effects , Lymphocytes/immunology , Receptors, Antigen, B-Cell/drug effects , Receptors, Antigen, B-Cell/metabolism , Animals , Complementarity Determining Regions/drug effects , Complementarity Determining Regions/genetics , Complementarity Determining Regions/metabolism , Cyclophosphamide/therapeutic use , Female , Granulocyte-Macrophage Colony-Stimulating Factor/therapeutic use , Immunoglobulin Heavy Chains/drug effects , Immunoglobulin Heavy Chains/genetics , Immunoglobulin Heavy Chains/metabolism , Immunoglobulin Joining Region/drug effects , Immunoglobulin Joining Region/metabolism , Immunoglobulin Variable Region/drug effects , Immunoglobulin Variable Region/metabolism , Leukocytes/drug effects , Leukopenia/chemically induced , Leukopenia/drug therapy , Lymphocytes/metabolism , Mice, Inbred BALB C , Receptors, Antigen, B-Cell/immunology
Sci Immunol ; 6(57)2021 03 02.
Article in English | MEDLINE | ID: covidwho-1115087


Pediatric COVID-19 following SARS-CoV-2 infection is associated with fewer hospitalizations and often milder disease than in adults. A subset of children, however, present with Multisystem Inflammatory Syndrome in Children (MIS-C) that can lead to vascular complications and shock, but rarely death. The immune features of MIS-C compared to pediatric COVID-19 or adult disease remain poorly understood. We analyzed peripheral blood immune responses in hospitalized SARS-CoV-2 infected pediatric patients (pediatric COVID-19) and patients with MIS-C. MIS-C patients had patterns of T cell-biased lymphopenia and T cell activation similar to severely ill adults, and all patients with MIS-C had SARS-CoV-2 spike-specific antibodies at admission. A distinct feature of MIS-C patients was robust activation of vascular patrolling CX3CR1+ CD8+ T cells that correlated with the use of vasoactive medication. Finally, whereas pediatric COVID-19 patients with acute respiratory distress syndrome (ARDS) had sustained immune activation, MIS-C patients displayed clinical improvement over time, concomitant with decreasing immune activation. Thus, non-MIS-C versus MIS-C SARS-CoV-2 associated illnesses are characterized by divergent immune signatures that are temporally distinct from one another and implicate CD8+ T cells in the clinical presentation and trajectory of MIS-C.

COVID-19/immunology , Lymphocyte Activation , Systemic Inflammatory Response Syndrome/immunology , T-Lymphocytes/immunology , Adolescent , Adult , Aging/immunology , Child , Child, Preschool , Female , Flow Cytometry , Humans , Leukopenia/immunology , Male , Young Adult