RESUMEN
Understanding how follicular helper T cells (TFH) regulate the specialization, maturation, and differentiation of adaptive B cell immunity is crucial for developing durable high-affinity immune protection. Using indexed single-cell molecular strategies, we reveal a skewed intraclonal assortment of higher-affinity T cell receptors and the distinct molecular programming of the localized TFH compartment compared with emigrant conventional effector TH cells. We find a temporal shift in B cell receptor class switch, which permits identification of inflammatory and anti-inflammatory modules of transcriptional programming that subspecialize TFH function before and during the germinal center (GC) reaction. Late collapse of this local primary GC reaction reveals a persistent post-GC TFH population that discloses a putative memory TFH program. These studies define subspecialized antigen-specific TFH transcriptional programs that progressively change with antibody class-specific evolution of high-affinity B cell immunity and a memory TFH transcriptional program that emerges upon local GC resolution.
Asunto(s)
Células T Auxiliares Foliculares , Linfocitos T Colaboradores-Inductores , Antígenos , Centro Germinal , Isotipos de Inmunoglobulinas , Receptores de Antígenos de Linfocitos BRESUMEN
Antibodies are produced across multiple isotypes with distinct properties that coordinate initial antigen clearance and confer long-term antigen-specific immune protection. Here, we interrogate the molecular programs of isotype-specific murine plasma cells (PC) following helper T cell-dependent immunization and within established steady-state immunity. We developed a single-cell-indexed and targeted molecular strategy to dissect conserved and divergent components of the rapid effector phase of antigen-specific IgM+ versus inflammation-modulating programs dictated by type 1 IgG2a/b+ PC differentiation. During antibody affinity maturation, the germinal center (GC) cycle imparts separable programs for post-GC type 2 inhibitory IgG1+ and type 1 inflammatory IgG2a/b+ PC to direct long-term cellular function. In the steady state, two subsets of IgM+ and separate IgG2b+ PC programs clearly segregate from splenic type 3 IgA+ PC programs that emphasize mucosal barrier protection. These diverse isotype-specific molecular pathways of PC differentiation control complementary modules of antigen clearance and immune protection that could be selectively targeted for immunotherapeutic applications and vaccine design.
Asunto(s)
Diferenciación Celular , Centro Germinal , Células Plasmáticas , Animales , Antígenos , Inmunoglobulina G/genética , Inmunoglobulina M , Ratones , Células Plasmáticas/citología , Análisis de la Célula Individual , Linfocitos T Colaboradores-InductoresRESUMEN
Adaptive T and B lymphocytes expand, respond, and persist across a multitude of separable cell differentiation states. Small compartments of these cells present defined cell surface phenotype, but express potentially divergent immune functions. Here, we use high resolution flow cytometry to provide direct access to rare lymphocyte subpopulations for evaluation of steady-state or reactive transcriptional programs. We sort and index single cells by phenotype in 384-well format for quantification of targeted gene amplification through RNA sequencing (single cell qtSEQ). For complete details on the use and execution of this profile, please refer to Dufaud et al. (2021).
Asunto(s)
Linfocitos B , Subgrupos Linfocitarios , Citometría de Flujo , Recuento de Linfocitos , Análisis de Secuencia de ARNRESUMEN
Kidney-alone transplant (KAT) candidates may be disadvantaged by the allocation priority given to multi-organ transplant (MOT) candidates. This study identified potential KAT candidates not receiving a given kidney offer due to its allocation for MOT. Using the Organ Procurement and Transplant Network (OPTN) database, we identified deceased donors from 2002 to 2017 who had one kidney allocated for MOT and the other kidney allocated for KAT or simultaneous pancreas-kidney transplant (SPK) (n = 7,378). Potential transplant recipient data were used to identify the "next-sequential KAT candidate" who would have received a given kidney offer had it not been allocated to a higher prioritized MOT candidate. In this analysis, next-sequential KAT candidates were younger (p < .001), more likely to be racial/ethnic minorities (p < .001), and more highly sensitized than MOT recipients (p < .001). A total of 2,113 (28.6%) next-sequential KAT candidates subsequently either died or were removed from the waiting list without receiving a transplant. In a multivariable model, despite adjacent position on the kidney match-run, mortality risk was significantly higher for next-sequential KAT candidates compared to KAT/SPK recipients (hazard ratio 1.55, 95% confidence interval 1.44, 1.66). These results highlight implications of MOT allocation prioritization, and potential consequences to KAT candidates prioritized below MOT candidates.
Asunto(s)
Trasplante de Riñón , Trasplante de Órganos , Trasplante de Páncreas , Obtención de Tejidos y Órganos , Humanos , Donantes de Tejidos , Listas de EsperaRESUMEN
We studied End-Stage Renal Disease (ESRD) in living kidney donors (LKDs) who donated in the United States between 1994 and 2016 (n = 123 526), using Organ Procurement and Transplantation Network and Centers for Medicare and Medicaid Services data. Two hundred eighteen LKDs developed ESRD, with a median of 11.1 years between donation and ESRD. Absolute 20-year risk was low but not uniform, with risk associated with race, age, and sex and increasing exponentially over time. LKDs had increased risk of ESRD if they were male (adjusted hazard ratio [aHR]: 1.75, 95% confidence interval [95%CI]: 1.33-2.31), had higher BMI (aHR: 1.34 per 5 kg/m2 , 95%CI: 1.10-1.64) or lower estimated GFR (aHR: 0.89 per 10 mL/min, 95% CI: 0.80-0.99), were first-degree relatives of the recipient (parent: [aHR: 2.01, 95% CI: 1.26-3.21]; full sibling [aHR: 1.87, 95%CI: 1.23-2.84]; identical twin [aHR: 19.79, 95%CI: 7.65-51.24]), or lived in lower socioeconomic status neighborhoods at donation (aHR: 0.87 per $10k increase; 95%CI: 0.77-0.99). We found a significant interaction between donation age and race, with higher risk at older ages for white LKDs (aHR: 1.26 per decade, 95%CI: 1.04-1.54), but higher risk at younger ages for black LKDs (aHR: 0.75 per decade, 95%CI: 0.57-0.99). These findings further inform risk assessment of potential LKDs.
Asunto(s)
Fallo Renal Crónico/epidemiología , Trasplante de Riñón , Donadores Vivos/provisión & distribución , Nefrectomía/efectos adversos , Medición de Riesgo/métodos , Obtención de Tejidos y Órganos/métodos , Adulto , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Fallo Renal Crónico/etiología , Masculino , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Virginia/epidemiologíaRESUMEN
Glutamate carboxypeptidase II (GCP II) inhibition has previously been shown to be protective against long-term neuropathy in diabetic animals. In the current study, we have determined that the GCP II inhibitor 2-(phosphonomethyl) pentanedioic acid (2-PMPA) is protective against glucose-induced programmed cell death (PCD) and neurite degeneration in dorsal root ganglion (DRG) neurons in a cell culture model of diabetic neuropathy. In this model, inhibition of caspase activation is mediated through the group II metabotropic glutamate receptor, mGluR3. 2-PMPA neuroprotection is completely reversed by the mGluR3 antagonist (S)-alpha-ethylglutamic acid (EGLU). In contrast, group I and III mGluR inhibitors have no effect on 2-PMPA neuroprotection. Furthermore, we show that two mGluR3 agonists, the direct agonist (2R,4R)-4-aminopyrrolidine-2, 4-dicarboxylate (APDC) and N-acetyl-aspartyl-glutamate (NAAG) provide protection to neurons exposed to high glucose conditions, consistent with the concept that 2-PMPA neuroprotection is mediated by increased NAAG activity. Inhibition of GCP II or mGluR3 may represent a novel mechanism to treat neuronal degeneration under high-glucose conditions.