Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
12,134
result(s) for
"CD4 Antigens - analysis"
Sort by:
Household point of care CD4 testing and isoniazid preventive therapy initiation in a household TB contact tracing programme in two districts of South Africa
by
Charalambous, Salome
,
Lewis, James J.
,
Churchyard, Gavin J.
in
Acquired immune deficiency syndrome
,
Adolescent
,
Adult
2018
In South Africa, TB household contact tracing provides an opportunity for increased TB and HIV case finding. We aimed to determine the effect of two new potential interventions for TB contact tracing programmes: Point of Care CD4 (PoC CD4) on HIV linkage to care and household Isoniazid Preventive Therapy (IPT) provision on uptake and retention of IPT.
A pragmatic, three-arm, cluster-randomized trial was undertaken. TB Household contacts were randomised to 3 arms: 1) Standard of Care TB and HIV testing (SOC); 2) SOC with POC CD4 for those testing HIV positive; 3) SOC with POC CD4 and IPT for eligible household members. Linkage to care within 90 days was assessed either through patient visits (at 10 weeks and 6 months) or via telephonic contact.
2,243 index TB patients and 3,012 contacts (64,3% female, median age 30 years) were enrolled. On self-report, 26(1.2%) were currently receiving TB treatment and 1816 (60.3%) reported a prior HIV test. HIV testing uptake was 34.7% in the SoC arm, 40.2% in the PoC CD4 arm (RR1.16, CI 0.99-1.36, p-value = 0.060) and 39.9% in the PoC CD4 + HH-IPT arm (RR = 1.15, CI 0.99-1.35, p-value = 0.075). Linkage to care within 3 months was 30.8% in the SoC arm and 42.1% in the POC CD4 arms (RR 1.37; CI: 0.68-2.76, p-value = 0.382). 20/21 contacts (95.2%) initiated IPT in the PoC CD4 + HH-IPT arm, compared to 3/20 (15.0%) in the PoC CD4 arm (p = 0.004; p-value from Fisher's exact test < 0.001). Among 3,008 contacts screened for tuberculosis, 15 (3.4%) had bacteriologically confirmed TB with an overall yield of TB of 0.5% (95% CI: 0.3%, 0.8%).
Household PoC CD4 testing and IPT initiation is feasible. There was only weak evidence that PoCCD4 led to a small increase in HCT uptake and no evidence for an increase in linkage-to-care. IPT initiation and completion was increased by the household intervention. Although feasible, these interventions had low impact due to the low uptake of HIV testing in households.
Journal Article
CD28-Negative CD4+and CD8+T Cells in Antiretroviral Therapy—Naive HIV-Infected Adults Enrolled in Adult Clinical Trials Group Studies
2012
Background. Individuals infected with human immunodeficiency virus (HIV) have higher risk than HIV-negative individuals for diseases associated with aging. T-cell senescence, characterized by expansion of cells lacking the costimulatory molecule CD28, has been hypothesized to mediate these risks. Methods. We measured the percentage of CD28 - CD4 + and CD8 + T cells from HIV-infected treatment-naive adults from 5 Adult Clinical Trials Group (ACTG) antiretroviral therapy (ART) studies and the ALLRT (ACTG Longitudinal Linked Randomized Trials) cohort, and from 48 HIV-negative adults. Pretreatment and 96-week posttreatment %CD28 - cells were assessed using linear regression for associations with age, sex, race/ethnicity, CD4 count, HIV RNA, ART regimen, and hepatitis C virus (HCV) infection. Results. In total, 1291 chronically HIV-infected adults were studied. Pretreatment, lower CD4 count was associated with higher %CD28 - CD4 + and %CD28 - CD8 + cells. For CD8 + cells, younger age and HCV infection were associated with a lower %CD28 - . ART reduced %CD28 - levels at week 96 among virally suppressed individuals. Older age was strongly predictive of higher %CD28 - CD8 + . Compared to HIV-uninfected individuals, HIV-infected individuals maintained significantly higher %CD28 - . Conclusions. Effective ART reduced the proportion of CD28 - T cells. However, levels remained abnormally high and closer to levels in older HIV-uninfected individuals. This finding may inform future research of increased rates of age-associated disease in HIV-infected adults.
Journal Article
Immune status is prognostic for poor survival in colorectal cancer patients and is associated with tumour hypoxia
by
Humphries, Matthew P.
,
Richman, Susan D.
,
Loughrey, Maurice B.
in
631/67/1504/1885
,
631/67/1857
,
631/67/327
2020
Background
Immunohistochemical quantification of the immune response is prognostic for colorectal cancer (CRC). Here, we evaluate the suitability of alternative immune classifiers on prognosis and assess whether they relate to biological features amenable to targeted therapy.
Methods
Overall survival by immune (CD3, CD4, CD8, CD20 and FOXP3) and immune-checkpoint (ICOS, IDO-1 and PD-L1) biomarkers in independent CRC cohorts was evaluated. Matched mutational and transcriptomic data were interrogated to identify associated biology.
Results
Determination of immune-cold tumours by combined low-density cell counts of CD3, CD4 and CD8 immunohistochemistry constituted the best prognosticator across stage II–IV CRC, particularly in patients with stage IV disease (HR 1.98 [95% CI: 1.47–2.67]). These immune-cold CRCs were associated with tumour hypoxia, confirmed using CAIX immunohistochemistry (
P
= 0.0009), which may mediate disease progression through common biology (
KRAS
mutations, CRIS-B subtype and
SPP1
mRNA overexpression).
Conclusions
Given the significantly poorer survival of immune-cold CRC patients, these data illustrate that assessment of CD4-expressing cells complements low CD3 and CD8 immunohistochemical quantification in the tumour bulk, potentially facilitating immunophenotyping of patient biopsies to predict prognosis. In addition, we found immune-cold CRCs to associate with a difficult-to-treat, poor prognosis hypoxia signature, indicating that these patients may benefit from hypoxia-targeting clinical trials.
Journal Article
Aire-Dependent Thymic Development of Tumor-Associated Regulatory T Cells
2013
Despite considerable interest in the modulation of tumor-associated Foxp3 + regulatory T cells (T regs ) for therapeutic benefit, little is known about the developmental origins of these cells and the nature of the antigens that they recognize. We identified an endogenous population of antigen-specific T regs (termed MJ23 T regs ) found recurrently enriched in the tumors of mice with oncogene-driven prostate cancer. MJ23 T regs were not reactive to a tumor-specific antigen but instead recognized a prostate-associated antigen that was present in tumor-free mice. MJ23 T regs underwent autoimmune regulator (Aire)—dependent thymic development in both male and female mice. Thus, Aire-mediated expression of peripheral tissue antigens drives the thymic development of a subset of organ-specific T regs , which are likely coopted by tumors developing within the associated organ.
Journal Article
The composition of T-cell subsets are altered in the burn wound early after injury
by
Rani, Meenakshi
,
Schwacha, Martin G.
in
Animals
,
Antigens, CD - analysis
,
Antigens, CD - immunology
2017
Burn-induced inflammation leads to impaired immune responses resulting in increased morbidity and mortality. T-cells are central in the immune response and circulating CD4 and CD8 T-cells have been used to evaluate immune status; however, the role of these T-cell subsets in the burn wound is unknown.
Male C57BL/6 mice were subjected to a major 3rd degree scald burn or sham treatment. Twenty-four hours later, full thickness skin samples from sham mice and the burn wounds were collected and single cells were isolated and analyzed for αβ TCR, γδ TCR, CD3, CD4, CD8 and CD69 expressions by flow cytometry.
The burn wound contained significantly greater numbers of T-cells than skin from sham mice, due to a profound infiltration of αβ T-cells. These infiltrating αβ T-cells were primarily suppressor T-cells with a CD8+ or CD8-CD4- phenotype. The 15-fold increase in CD8+ αβ T-cells caused a decrease in the CD4:CD8 ratio from 0.7 in sham skin to 0.3 in the burn wound. In contrast, the majority of the γδ T-cells in sham skin were CD4-CD8-, which decreased 9-fold in the burn wound. CD69 expression was suppressed on burn wound αβ T-cells, but increased on γδ T-cells in the burn wound.
The infiltrating burn wound αβ T-cells likely act to quell inflammation. In contrast wound γδ T-cells were activated with elevated CD4 and CD69 expression. Thus, these two distinct T-cell subsets likely differentially regulate the burn wound inflammatory response.
Journal Article
Antibody-mediated vascular rejection of kidney allografts: a population-based study
by
Anglicheau, Dany
,
Beuscart, Thibaut
,
Suberbielle, Caroline
in
allografting
,
antibodies
,
Biological and medical sciences
2013
Rejection of allografts has always been the major obstacle to transplantation success. We aimed to improve characterisation of different kidney-allograft rejection phenotypes, identify how each one is associated with anti-HLA antibodies, and investigate their distinct prognoses.
Patients who underwent ABO-compatible kidney transplantations in Necker Hospital and Saint-Louis Hospital (Paris, France) between Jan 1, 1998, and Dec 31, 2008, were included in our population-based study. We assessed patients who provided biopsy samples for acute allograft rejection, which was defined as the association of deterioration in function and histopathological lesions. The main outcome was kidney allograft loss—ie, return to dialysis. To investigate distinct rejection patterns, we retrospectively assessed rejection episodes with review of graft histology, C4d in allograft biopsies, and donor-specific anti-HLA antibodies.
2079 patients were included in the main analyses, of whom 302 (15%) had acute biopsy-proven rejection. We identified four distinct patterns of kidney allograft rejection: T cell-mediated vascular rejection (26 patients [9%]), antibody-mediated vascular rejection (64 [21%]), T cell-mediated rejection without vasculitis (139 [46%]), and antibody-mediated rejection without vasculitis (73 [24%]). Risk of graft loss was 9·07 times (95 CI 3·62–19·7) higher in antibody-mediated vascular rejection than in T cell-mediated rejection without vasculitis (p<0·0001), compared with an increase of 2·93 times (1·1–7·9; P=0·0237) in antibody-mediated rejection without vasculitis and no significant rise in T cell-mediated vascular rejection (hazard ratio [HR] 1·5, 95% CI 0·33–7·6; p=0·60).
We have identified a type of kidney rejection not presently included in classifications: antibody-mediated vascular rejection. Recognition of this distinct phenotype could lead to the development of new treatment strategies that could salvage many kidney allografts.
None.
Journal Article
CD4+CD25+Foxp3+ regulatory T cells induce cytokine deprivation–mediated apoptosis of effector CD4+ T cells
by
Zheng, Lixin
,
Pandiyan, Pushpa
,
Ishihara, Satoru
in
Animals
,
Apoptosis - immunology
,
Apoptosis - physiology
2007
A key issue in mammalian immunology is how CD4
+
CD25
+
Foxp3
+
regulatory T cells (T
reg
cells) suppress immune responses. Here we show that T
reg
cells induced apoptosis of effector CD4
+
T cells
in vitro
and
in vivo
in a mouse model of inflammatory bowel disease. T
reg
cells did not affect the early activation or proliferation of effector CD4
+
T cells. Cytokines that signal through the common γ-chain suppressed T
reg
cell–induced apoptosis. T
reg
cell–induced effector CD4
+
T cell death required the proapoptotic protein Bim, and effector CD4
+
T cells incubated with T
reg
cells showed less activation of the prosurvival kinase Akt and less phosphorylation of the proapoptotic protein Bad. Thus, cytokine deprivation–induced apoptosis is a prominent mechanism by which T
reg
cells inhibit effector T cell responses.
Journal Article
Stromal infiltration of CD8 T cells is associated with improved clinical outcome in HPV-positive oropharyngeal squamous carcinoma
2015
Background:
Patients with human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC) have a better prognosis than those with HPV-negative tumours. There is interest in de-escalating their treatment but strategies are needed for risk stratification to identify subsets with a poor prognosis. This study investigated tumour-infiltrating lymphocytes (TILs) in relation to HPV tumour status and patient survival.
Methods:
Biopsies from 218 patients diagnosed with OPSCC between 2002 and 2011, who underwent chemo/radiotherapy were analysed for HPV by PCR,
in-situ
hybridisation and p16 immunohistochemistry (IHC). One hundred and thirty-nine samples with concordant HPV detection were analysed for CD3, CD4, CD8 and FoxP3 expression in tumour and stromal regions using multiplexIHC and multispectral image analysis. Labelling of smooth muscle actin (SMA) identified activated stroma.
Results:
Human papillomavirus-positive compared with HPV-negative OPSCC had higher infiltration in both tumour and stromal areas of CD4 and CD8 T cells but not FoxP3 T regulatory cells. Only CD3+CD8+ stromal and not tumour area infiltration was associated with increased survival (
P
=0.02). There was significantly higher SMA expression in HPV-positive compared with -negative tumours, which did not correlate with survival.
Conclusions:
Studies of TILs for risk stratification in OPSCC should assess stromal infiltration.
Journal Article
Open-Capsule Budesonide for Refractory Celiac Disease
by
Wu, Tsung-Teh
,
Murray, Joseph A
,
Sharma, Ayush
in
Administration, Oral
,
Aged
,
Aged, 80 and over
2017
Refractory celiac disease (RCD) is a rare condition often associated with poor prognosis. Various immunosuppressive medications (IMs) have been used with modest success. We describe outcomes in patients treated with open-capsule budesonide (OB), including those for whom IM treatment failed.
We identified RCD patients treated with OB at Mayo Clinic, Rochester, Minnesota from 2003 to 2015. Demographic, serologic, and clinical variables were analyzed.
We identified 57 patients who received OB for suspected RCD. Based on clonal T-cell receptor gamma gene rearrangement or aberrant phenotype of intraepithelial lymphocytes (IELs), 13 patients (23%) were classified as having RCD-2 and 43 (75%) as RCD-1. In one patient (2%) TCR gene rearrangement status was unknown. Most patients were women (69%), mean (s.d.) age was 60.5 (3.5) years and body mass index was 28.4 (4.5) kg/m
. The majority had diarrhea (72%), with median of 6 bowel movements per day (range, 4-25). IM treatment (azathioprine, systemic corticosteroids, or regular budesonide) had failed in nearly half. Twenty-four patients (42%) had anemia and 12 (21%) had hypoalbuminemia. All had Marsh 3 lesions on biopsy: 3a (19%), 3b (46%), and 3c (35%). After OB therapy, the majority had clinical (92%) and histologic (89%) improvement. Follow-up biopsy in 7 out of 13 patients with RCD-2 (53%) showed an absence of clonal TCR gamma gene rearrangement/aberrant IEL phenotype previously seen. On follow-up, 2 patients (4%) died of enteropathy-associated T-cell lymphoma.
Most patients with RCD show clinical and histopathologic improvement with OB therapy, including those with failure of IMs. OB is a promising therapeutic option for management of RCD.
Journal Article
Preparation and characterization of monoclonal antibodies recognizing two CD4 isotypes of Microminipigs
2020
Cluster of differentiation 4 (CD4) molecule expressed on the leukocytes is known to function as a co-receptor for class II major histocompatibility complex (MHC) binding to T cell receptor (TCR) on helper T cells. We previously identified two CD4 alleles (CD4.A and CD4.B) in a Microminipig population based on nucleotide sequencing and PCR detection of their gene sequences. However, CD4.B protein expression was not examined because of the unavailability of a reactive antibody to a CD4.B epitope. In this study, we have produced two swine-specific monoclonal antibodies (mAbs) against CD4.B molecules, one that recognizes only CD4.B (b1D7) and the other that recognizes both the CD4.A and CD4.B alleles (x1E10) and that can be used to distinguish CD4 T cell subsets by flow cytometry and immunohistochemistry. Using these two mAbs, we identified CD4.A and CD4.B allele-specific proteins on the surface of CD4.A (+/+) and CD4.B (+/+) T cells at a similar level of expression. Moreover, stimulation of peripheral blood mononuclear cells (PBMCs) derived from CD4.A (+/+) and CD4.B (+/+) swine with toxic shock syndrome toxin-1 (TSST-1) in vitro similarly activated both groups of cells that exhibited a slight increase in the CD4/CD8 double positive (DP) cell ratio. A large portion of the DP cells from the allelic CD4.A (+/+) and CD4.B (+/+) groups enhanced the total CD4 and class I swine leukocyte antigen (SLA) expression. The x1E10 mAb delayed and reduced the TSST-1-induced activation of CD4 T cells. Thus, CD4.B appears to be a functional protein whose expression on activated T cells is analogous to CD4.A.
Journal Article