An Effective Method for Depleting MatureT Lymphocytes from Bone Marrow Cells──Two－step Percoll Centrifugation

In the present paper we have observed the effect of discontinuous gradient two-step Percoll centrifugation on depleting mature T lymphocytes from normal bone marrow. The pre-/post-Percoll percentage of CD34+, and Leu4+ cells in MNC was counted by using APAAP technique. As the two-step Percoll centrifugation is simple,and time saving, and decreases the incidence of contamination of cultured cells as well,This technique may be of value in serum-free culture of hematopoietic cells and immunological studies.

Haematology Parameters of Apparently Healthy Prospective Whole Blood Donors in a Nigerian Hospital Setting

Background: Adequate selection of a prospective whole blood donor protects his health and safety of the recipient. Objectives: The main objective of this study was to determine the haematology parameters of apparently healthy prospective whole blood donors. Participants and Methods: This was a hospital based prospective study carried out from August to October 2020 at the blood transfusion unit of the Lagos State University Teaching Hospital (LASUTH), Ikeja, Nigeria. A structured pretested questionnaire was used for data collection. The socio demographic status and the haematology parameters of apparently healthy prospective whole blood donors who tested negative for HIV, hepatitis B and C markers were captured. Obtained data were analysed with the statistical package for the social scientist software version 20. Results: One hundred male (97.1%) and three female (2.9%) apparently healthy prospective whole blood donors were studied. The median age of study subjects was 30 years. Obtained median haematology parameter values were 13 g/dl, 40%, 4.9/nl and 203.9/nl for haemoglobin concentration, haematocrit, total white cell and platelet counts respectively. The median values for the mean corpuscular haemoglobin concentration (MCHC), mean corpuscular haemoglobin (MCH) and mean corpuscular volume (MCV) of participants were 32.6 g/dl, 27.7 pg and 85.7 fl respectively. Observed prevalence of subnormal haematology parameters for haemoglobin concentration, total white cells, platelets were 12.6%, 25.2%, and 13.6% respectively. Also subnormal values for MCHC, MCH, MCV were 11.7%, 26.2%, and 16.5% respectively among prospective whole blood donors in this study. No higher than normal haematology parameter values were observed. Median values for erythrocyte sedimentation rate was 8.4 mm/hr. Conclusion: A significant percentage of apparently healthy prospective whole blood donors had subnormal haematology parameters values. Obtained normal values in our study are comparable with local reference range reports from previous studies in Nigeria and other parts of Africa. 124947 .

Roles of microRNAs in immunopathogenesis of non-alcoholic fatty liver disease revealed by integrated analysis of microRNA and mRNA expression profiles

BACKGROUND： The integrative analysis of microRNA and mRNA expression profiles can elucidate microRNA-targeted gene function. We used this technique to elucidate insights into the immunological pathology of non-alcoholic fatty liver disease （NAFLD）. METHODS： We analyzed differentially expressed microRNA and mRNA expression profiles of CD4＋ T lymphocytes from the liver and mesenteric lymph nodes （MLNs） of mice with NAFLD using microarrays and RNA sequencing. Normal mice were used as controls. The target genes of microRNAs were predicted by TargetScan. Integrative analysis showed that the mRNAs were overlapped with microRNAs. Furthermore, the Gene Ontology （GO） and Kyoto Encyclopedia of Genes and Genomes （KEGG） analyses were performed to predict the key genes and pathways. Then, 16 microRNAs and 10 mRNAs were validated by qRT-PCR. RESULTS： Microarray analysis suggested that 170 microRNAs were significantly de-regulated in CD4＋ T lymphocytes from the liver between the two groups. Eighty mRNAs corresponded with microRNA targeted genes. KEGG analysis indicated that the MAPK pathway was consistently augmented in the liver of NAFLD mice. miR-23b, let-7e, miR-128 and miR-130b possibly played significant parts in the MAPK pathways. Furthermore, between the two groups, 237 microRNAs were significantly deregulated in CD4＋ T lymphocytes from MLNs. 38 mRNAs coincided with microRNA target genes. The metabolic pathway was consistently enriched in the MLNs of NAFLD mice. miR- 206-3p, miR-181a-Sp, miR-29c-3p and miR-30d-5p likely play important roles in the regulation of metabolic pathways. CONCLUSION： The results of this study presented a new perspective on the application of integrative analysis to identify complex regulation means involved in the immunological pathogenesis of NAFLD.

Changes of CD4^+CD25^+ Regulatory T Cells in Patients with Acute Coronary Syndrome and the Effects of Atorvastatin

The function of CD4＋CD25＋ regulatory T lymphocytes （Treg） in patients with acute coronary syndrome （ACS） and the effects of atorvastatin were investigated. Forty-eight patients with ACS were randomly divided into two groups： group C receiving conventional therapy （n=24）, and group C＋A receiving conventional therapy＋atorvastatin （10 mg/day, n=24）. T lymphocytes from ACS patients （before and 2 weeks after the treatment） or 18 healthy subjects were separated and the flow cytometry was used to measure the percentage of Treg. The inhibitory ability of Treg on effector T cells was determined by mixed lymphocyte reaction （MLR）. ELISA was used to measure the serum levels of cytokines （IL-10, TGF-β1 and IFN-γ） before and after treatment. The results showed that as compared with normal control group, Treg percentage was decreased significantly （P〈0.01）, the inhibitory ability of Treg on the T lymphocytes proliferation was reduced （P〈0.01）, IFN-γ levels were increased and IL-10 and TGF-β1 levels were lowered in ACS patients. After treatment with atorvastatin, Treg percentage and the inhibitory ability of Treg on T lymphocytes proliferation were significantly increased in ACS patients. Serum IFN-γ was decreased significantly, while IL-10 and TGF-β1 were elevated significantly as compared with the non-atorvastatin group. The number of Treg was positively correlated with serum TGF-β1, but negatively with serum IFN-γ and CRP. It was concluded that ACS was associated with decreased number and defected function of Treg, which may play an important role in initiating immune-inflammatory response in ACS. The inhibitory effects of atorvastatin on inflammation in ACS may be due to its beneficial effects on Treg and restoration of immune homeostasis.

Methylprednisolone inhibits activated CD4^+ T cell survival promoted by toll-like receptor ligands

BACKGROUND: Methylprednisolone (MP) can affect the survival of CD4(+) T lymphocytes and plays an important role in adaptive immune responses; however, its mechanism of action is not clear. Recent studies have shown that toll-like receptors (TLRs) on CD4(+) T cells can directly modulate adaptive immune responses by affecting the survival and proliferation of activated CD4(+) T cells. This study aimed to investigate the relationship between MP, TLRs and activated CD4(+) T cells. METHODS: We separated and purified CD4(+) T cells from mice, activated them in vitro, and co-cultured them with TLR ligands, MP or inhibitors of nuclear factor-kappa B (NF-kappa B) and activator protein 1 (AP-1). We then assessed CD4(+) T cell survival and proliferation and the expression of NF-kappa B and AP-1. RESULTS: Activated CD4(+) T cells showed increased TLR-3 and TLR-9 mRNA expression, but polyinosinic-polycytidylic acid (poly I:C) and MP had no effect on the expression of these mRNAs. Still, poly I:C and CpG oligodeoxynucleotides (CpG DNA) increased the survival of activated CD4(+) T cells, whereas MP reduced the survival of activated CD4(+) T cells and could inhibit the survival effects of poly I:C and CpG DNA. The NF-kappa B essential modifier-binding domain (NBD) inhibited the survival of activated CD4(+) T cells induced by poly I:C and CpG DNA, but the AP-1 inhibitor crucumin did not have the same effect. The increased expression of NF-kappa B induced by poly I:C and CpG DNA in activated CD4(+) T cells could be inhibited by MP, but the same was not true for the increased expression of AP-1 induced by poly I:C and CpG DNA. Finally, the proliferation of activated CD4(+) T cells was not affected by poly I:C or MP. CONCLUSION: The survival of activated CD4(+) T cells is promoted by TLR ligands, but this effect is inhibited by MP.

Effects of pituitary adenylate cyclase activating polypeptide on CD4^+/CD8^+T cell levels after traumatic brain injury in a rat model

BACKGROUND:The effect of pituitary adenylate cyclase activating polypeptide(PACAP)during traumatic brain injury(TBI) and whether it can modulate secondary injury has not been reported previously.The present study evaluated the potential protective effects of ventricular infusion of PACAP in a rat model of TBI.METHODS:Male Sprague Dawley rats were randomly divided into 3 treatment groups(n=6,each):sham-operated,vehicle(normal saline)^+TBI,and PACAP^+TBI.Normal saline or PACAP(1 ug/5uL) was administered intracerebroventricularly 20 minutes before TBI.Right parietal cortical contusion was produced via a weight-dropping method.Brains were extracted 24 hours after trauma.Histological changes in brains were examined by HE staining.The numbers of CD4^+ and CD8^+ T cells in blood and the spleen were detected via flow cytometry.RESULTS:In injured brain regions,edema,hemorrhage,inflammatory cell infiltration,and swollen and degenerated neurons were observed under a light microscope,and the neurons were disorderly arrayed in the hippocampi.Compared to the sham group,average CD4^+ CD8" lymphocyte counts in blood and the spleen were significantly decreased in rats that received TBI^+vehicle,and CD4^+ CD8^+ were increased.In rats administered PACAP prior to TBI,damage was attenuated as evidenced by significantly increased CD4^+,and decreased CD8^+,T lymphocytes in blood and the spleen.CONCLUSION:Pretreatment with PACAP may protect against TBI by influencing periphery T cellular immune function.

CD70 defines a subset of proinflammatory and CNSpathogenic TH1/TH17 lymphocytes and is overexpressed in multiple sclerosis

activation.Therefore,engagement of the costimulatory CD27/CD70 pathway is solely dependent on upregulation of CD70.However,the T cell-intrinsic effect and function of human CD70 remain underexplored.Herein,we describe that CD70 expression distinguishes proinflammatory CD4^(+)T lymphocytes that display an increased potential to migrate into the central nervous system(CNS).Upregulation of CD70 on CD4^(+)T lymphocytes is induced by TGF-β1 and TGF-β3,which promote a pathogenic phenotype.In addition,CD70 is associated with a TH1 and TH17 profile of lymphocytes and is important for T-bet and IFN-γexpression by both T helper subtypes.Moreover,adoptive transfer of CD70−/−CD4^(+)T lymphocytes induced less severe experimental autoimmune encephalomyelitis(EAE)disease than transfer of WT CD4^(+)T lymphocytes.CD70+CD4^(+)T lymphocytes are found in the CNS during acute autoimmune inflammation in humans and mice,highlighting CD70 as both an immune marker and an important costimulator of highly pathogenic proinflammatory TH1/TH17 lymphocytes infiltrating the CNS.

A novel CD4+CTL subtype characterized by chemotaxis and inflammation is involved in the pathogenesis of Graves’orbitopathy

Graves*orbitopathy(GO),the most severe manifestation of Graves'hyperthyroidism(GH),is an autoimmune-mediated inflammatory disorder,and treatments often exhibit a low efficacy.CD4+T cells have been reported to play vital roles in GO progression.To explore the pathogenic CD4-f T cell types that drive GO progression,we applied single-cell RNA sequencing(scRNA-Seq),T cell receptor sequencing(TCR-Seq),flow cytometry,immunofluorescence and mixed lymphocyte reaction(MLR)assays to evaluate CD4+T cells from GO and GH patients.scRNA-Seq revealed the novel GO-spedfic cell type CD4+cytotoxic T lymphocytes(CTLs),which are characterized by chemotactic and inflammatory features.The clonal expansion of this CD4+CTL population,as demonstrated by TCR-Seq,along with their strong cytotoxic response to autoantigens,localization in orbital sites,and potential relationship with disease relapse provide strong evidence for the pathogenic roles of GZMB and IFN-y-secreting CD4+CTLs in GO.Therefore,cytotoxic pathways may become potential therapeutic targets for GO.