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Purpose: Combination strategies leveraging chemotherapeutic agents and immunotherapy have held the promise as a method to improve benefit for patients with cancer. However, most chemotherapies have detrimental effects on immune homeostasis and differ in their ability to induce immunogenic cell death (ICD). The approval of pemetrexed and carboplatin with anti-PD-1 (pembrolizumab) for treatment of non–small cell lung cancer represents the first approved chemotherapy and immunotherapy combination. Although the clinical data suggest a positive interaction between pemetrexed-based chemotherapy and immunotherapy, the underlying mechanism remains unknown. Experimental Design: Mouse tumor models (MC38, Colon26) and high-content biomarker studies (flow cytometry, Quantigene Plex, and nCounter gene expression analysis) were deployed to obtain insights into the mechanistic rationale behind the efficacy observed with pemetrexed/anti-PD-L1 combination. ICD in tumor cell lines was assessed by calreticulin and HMGB-1 immunoassays, and metabolic function of primary T cells was evaluated by Seahorse analysis. Results: Pemetrexed treatment alone increased T-cell activation in mouse tumors in vivo, robustly induced ICD in mouse tumor cells and exerted T-cell–intrinsic effects exemplified by augmented mitochondrial function and enhanced T-cell activation in vitro. Increased antitumor efficacy and pronounced inflamed/immune activation were observed when pemetrexed was combined with anti-PD-L1. Conclusions: Pemetrexed augments systemic intratumor immune responses through tumor intrinsic mechanisms including immunogenic cell death, T-cell–intrinsic mechanisms enhancing mitochondrial biogenesis leading to increased T-cell infiltration/activation along with modulation of innate immune pathways, which are significantly enhanced in combination with PD-1 pathway blockade. See related commentary by Buque et al., p. 6890

Rationale: Latent autoimmune diabetes in adults (LADA) refers to an autoimmune disorder characterized with detectable islets antibodies in the early diagnosis and increased autoimmune beta-cell failure progression. Notably, this kind of diabetes seems to be confused with other phenotypic diabetes. Patient concerns: A young woman suffered an emotional exhaustion-induced LADA, showing asthenia, polydipsia, polyuria, and visible weight loss. The patient emotionally ended a 14-year romantic relationship, leading to the emotional flooding. Diagnoses: The data from physical examination and laboratory tests exhibited as follows: glutamic acid decarboxylase antibody (GADA) = 63.83 U/mL, the fasting blood glucose (FBG) = 13.3 mmol/L, and glycated haemoglobin (HbA1c) = 10.9%. According to levels of GADA, the patient was diagnosed as LADA. Interventions: The patient was clinically treated with insulin for 3-month. Then, running, diet-control, and emotional treatment were combined, such as the patient started a new relationship. Outcomes: An emotional recovery initiated from a new romantic relationship and a baby, showing normal levels of GAD65 (27.007 IU/mL) and FBG (5.46) mmol/L. Lessons: The emotional exhaustion might play a significant role in induction of LADA. It is important that individuals should maintain optimism, cheer, and a positive attitude.

Supplemental Digital Content is available in the text, Membranous glomerulonephritis (MGN) represents an immunologically mediated disease characterized by deposition of immune complexes in the glomerular subepithelial space. Persistent proteinuria at diagnosis predicts poor prognosis. Pregnancy with MGN is a risk of fetal loss and may worsen maternal renal function. Here, we report a lady with MGN and proteinuria achieved spontaneous remission and successful fetal outcome naive to any medications. The 26-year old woman had 1-year history of persistent proteinuria (5.5–12.56 g/24 hours) and biopsy-proven MGN. Histopathological characteristics included glomerular basement membrane spikes, subepithelial monoclonal IgG immunofluorescence, and diffuse electron dense deposits. She was sticking to a regular morning exercise routine without any medications. After successful delivery of a full-term baby girl, the mother had improved proteinuria (0.56 g/24 hours) and albuminuria (351.96 g/24 hours contrasting 2281.6 g/24 hours before pregnancy). The baby had normal height and body weight at 4 months old. We identified more pregnancies with MGN in 5 case reports and 5 clinical series review articles (7–33 cases included). Spontaneous remission of maternal MGN with good fetal outcome rarely occurred in mothers on immunosuppressive therapy. Mothers naive to immunosuppressive therapy may achieve spontaneous remission of maternal membranous glomerulonephritis and successful fetal outcome. Theoretically, fetus might donate stem cells to heal mother's kidney.

Supplemental digital content is available in the text, Gastrointestinal (GI) disorders often manifest similar symptoms with overlapping clinical diagnosis and unmet medical needs. Traditional Chinese medicine (TCM) has history-proven benefits for GI diseases; albeit language barrier prevents Western readers from accessing the original reports in Chinese. The TCM formula Si-Ni-San (SNS) consists of 4 herbs targeting on homeostatic disturbances characterized by “reflux” and “irritable” problems. Here we used SNS as a therapeutic tool to explore the common mechanisms of pathogenesis in non-neoplastic GI diseases. Data sources from PUBMED, Chinese National Knowledge Infrastructure, and Wanfang databases were searched for clinical trials. Comparisons were SNS as intervention and Western conventional medicine as control, which treat patients with upper GI disorders (gastroesophageal reflux disease, peptic ulcer, chronic gastritis, duodenogastric reflux), lower GI diseases (irritable bowel syndrome, ulcerative colitis), and functional dyspepsia. Participants and studies in accordance with the Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement were eligible. We used the Jadad scale to assess methodological qualities, the fixed or random-effect model to evaluate therapeutic efficacy, and the funnel plots to explore publication bias. Outcome was clinical efficacy defined by symptom relief with normal GI endoscopy, radiology, and pathology. We included 83 studies involving 7762 participants: 1708 versus 1397 of the upper GI disorders in 34 studies, 901 versus 768 of the lower GI diseases in 19 studies, 1641 versus 1348 of functional dyspepsia in 30 studies, and 328 versus 287 of relapse rate in 8 studies. Six studies had a Jadad score >2 points and the rest were

The Duffy antigen receptor for chemokines (DARC) is expressed in human erythrocytes and on endothelial cells lining postcapillary venules in kidney and spleen. DARC is a promiscuous chemokine receptor and a binding protein for the malarial parasite Plasmodium vivax. The expression of DARC by subsets of endothelial cells and neurons in discrete anatomic sites in the brain suggests that this enigmatic receptor may have multiple roles in normal and pathological physiology. Conservation of this promiscuous chemokine binding function is evident from the similarity in nucleotide sequence of DARC homologues from multiple species, as well as the high-affinity binding of human chemokines to murine and avian erythrocytes. Analysis of the functional domains of DARC using chimeric receptors and monoclonal antibodies to multiple extracellular domains localized chemokine binding to structures in the amino terminal extracellular domain (E1). Scatchard analysis demonstrated that a chimeric DARC receptor, composed of the E1 domain of DARC and the predicted hydrophobic helices and loops of interleukin-8RB (IL-8RB), bound IL-8, and MGSA with K D values almost identical to the wild type receptors and bound a repertoire of C-X-C and C-C chemokines characteristic of DARC. Although numerous reports have demonstrated that chemokines such as IL-8 are expressed in the brain, presumably by glial cells, little insight into the nature of their role in normal or pathological physiology in the nervous system has developed because the target cells that express the corresponding receptors have not yet been identified. Northern blotting experiments suggest that mRNA encoding DARC are expressed in the central nervous system, however, interpretation of this is unclear because of the ubiquitous expression of DARC lining postcapillary venules. This study provides direct evidence to localize expression of DARC in the cental nervous system. Immunohistochemical examination of human archival sections of the brain with monoclonal antibodies specific for DARC localize expression of DARC to cell bodies and processes of Purkinjie cells in the cerebellum. The immunohistochemical findings were supported by analysis of chemokine binding and radioligand crosslinking with membranes made from various brain fractions. The hierarchical expression of DARC in neurons in the cerebellum suggests that chemokines may play an important role in the modulation of neuronal activity by glial cells.

The Duffy antigen/receptor for chemokines (DARC), first identified on erythrocytes, functions not only as a promiscuous chemokine receptor but also as a receptor for the malarial parasite, Plasmodium vivax. The recent finding that DARC is ubiquitously expressed by endothelial cells lining postcapillary venules provides a possible insight into the function of this receptor because this anatomic site is an active interface for leukocyte trafficking. However, the biological significance of DARC is questionable since it has not yet been determined whether individuals lacking the expression of this protein on their erythrocytes (Duffy negative individuals), who are apparently immunologically normal, express the receptor on endothelial cells. However, we report here that DARC is indeed expressed in endothelial cells lining postcapillary venules and splenic sinusoids in individuals who lack the erythrocyte receptor. These findings are based on immunohistochemical, biochemical, and molecular biological analysis of tissues from Duffy negative individuals. We also present data showing that, in contrast to erythrocyte DARC, cells transfected with DARC internalize radiolabeled ligand. We conclude that the DARC may play a critical role in mediating the effects of proinflammatory chemokines on the interactions between leukocyte and endothelial cells since the molecular pathology of the Duffy negative genotype maintains expression on the latter cell type.

Nicotinamide phosphoribosyltransferase (NAMPT) catalyzes the first rate-limiting step in converting nicotinamide to NAD(+), essential for cellular metabolism, energy production, and DNA repair. NAMPT has been extensively studied because of its critical role in these cellular processes and the prospect of developing therapeutics against the target, yet how it regulates cellular metabolism is not fully understood. In this study we utilized liquid chromatography-mass spectrometry to examine the effects of FK866, a small molecule inhibitor of NAMPT currently in clinical trials, on glycolysis, the pentose phosphate pathway, the tricarboxylic acid (TCA) cycle, and serine biosynthesis in cancer cells and tumor xenografts. We show for the first time that NAMPT inhibition leads to the attenuation of glycolysis at the glyceraldehyde 3-phosphate dehydrogenase step due to the reduced availability of NAD(+) for the enzyme. The attenuation of glycolysis results in the accumulation of glycolytic intermediates before and at the glyceraldehyde 3-phosphate dehydrogenase step, promoting carbon overflow into the pentose phosphate pathway as evidenced by the increased intermediate levels. The attenuation of glycolysis also causes decreased glycolytic intermediates after the glyceraldehyde 3-phosphate dehydrogenase step, thereby reducing carbon flow into serine biosynthesis and the TCA cycle. Labeling studies establish that the carbon overflow into the pentose phosphate pathway is mainly through its non-oxidative branch. Together, these studies establish the blockade of glycolysis at the glyceraldehyde 3-phosphate dehydrogenase step as the central metabolic basis of NAMPT inhibition responsible for ATP depletion, metabolic perturbation, and subsequent tumor growth inhibition. These studies also suggest that altered metabolite levels in tumors can be used as robust pharmacodynamic markers for evaluating NAMPT inhibitors in the clinic.

The human erythrocyte chemokine receptor has recently been shown to be identical to the Duffy blood group antigen and is expressed in multiple organs, including kidney. Here we have examined the molecular properties of the renal isoform. Immunoblot analysis of erythrocyte and kidney detergent lysates, with a monoclonal antibody (Fy6) to the Duffy antigen, revealed that the renal isoform had a molecular mass of 43-45 kD, which could be distinguished from that observed in erythroid cells (38-47 kD). Chemical cross-linking of kidney membranes to 125I-melanoma growth stimulatory activity (MGSA) indicated that the renal chemokine receptor had a molecular mass of 38-45 kD. Binding of 125I-labeled MGSA to kidney membranes was competitively inhibited by the addition of unlabeled MGSA, IL-8, regulated on activation, normal T expressed and secrted, and monocyte chemotactic protein-1. Scatchard analysis of MGSA binding showed that the chemokine receptor from renal tissues had a binding affinity of 3.5 nM similar to that observed for the erythroid isoform (5-10 nM). The primary structure of the renal chemokine receptor predicted from the nucleotide sequence of cDNA from renal tissues is identical to that reported for the erythroid isoform. Immunocytochemical staining of kidney with Fy6 localized expression to endothelial cells present in postcapillary venules. These studies implicate the Duffy antigen/chemokine receptor in the complex interactions between postcapillary endothelial cells and granulocytes, which are modulated by pro-inflammatory chemokines.

Certain chemokine receptors serve as cofactors for HIV type 1 envelope (env)-mediated cell–cell fusion and virus infection of CD4-positive cells. Macrophage tropic (M-tropic) HIV-1 isolates use CCR5, and T cell tropic (T-tropic) strains use CXCR4. To investigate the cofactors used by simian immunodeficiency viruses (SIV), we tested four T-tropic and two M-tropic SIV env proteins for their ability to mediate cell–cell fusion with cells expressing CD4 and either human or nonhuman primate chemokine receptors. Unlike HIV-1, both M- and T-tropic SIV envs used CCR5 but not CXCR4 or the other chemokine receptors tested. However, by testing a panel of CCR5/CCR2b chimeras, we found that the structural requirements for CCR5 utilization by M-tropic and T-tropic SIV strains were different. T-tropic SIV strains required the second extracellular loop of CCR5 whereas a closely related M-tropic SIV strain could, like M-tropic HIV-1 strains, use the amino-terminal domain of CCR5. As few as two amino acid changes in the SIV env V3 domain affected the regions of CCR5 that were critical for fusogenic activity. Receptor signaling was not required for either fusion or infection. Our results suggest that viral tropism may be influenced not only by the coreceptors used by a given virus strain but also by how a given coreceptor is used.