The prevalence and clinical relevance of 2R/2R TYMS genotype in patients with gastrointestinal malignancies treated with fluoropyrimidine-based chemotherapy regimens.

INTRODUCTION: The prevalence of 2R/2R TYMS genotype is variable but estimated to be around 20-30% in Caucasians. The clinical relevance of TYMS 2R/2R genotype in predicting severe fluoropyrimidine-related adverse events (FrAE) is controversial. Here, we explored the prevalence and clinical relevance of 2R/2R TYMS genotype. METHODS: Between 2011 and 2018, 126 patients were genotyped for TYMS. FrAEs were graded according to CTCAE version 5.0. Fisher's exact test was used for statistical analysis. RESULTS: The prevalence of TYMS 2R/2R genotype was 24.6%. Among patients with TYMS genotypes (N = 71) that predict decreased TS expression, 2R/2R TYMS genotype was the most common TYMS genotype seen in female (57%) and African American (60%) patients. Among patients with genotypes that predict increased TS expression (N = 55), 12 patients had grade 3-4 FrAEs (22%), while among patients with genotypes that predict decreased TS expression (N = 71), 30 patients had grade 3-4 FrAEs (42%) (p = 0.0219). Compared to patients with genotypes predicting increased TS expression, 17 out of 31 patients (55%) with TYMS 2R/2R genotype had grade 3-4 FrAEs (p = 0.0039) and 15 out 40 patients (38%) with TYMS 2R/3RC and TYMS 3RC/3RC genotype had grade 3-4 FrAEs (p = 0.1108). CONCLUSION: The prevalence of TYMS 2R/2R genotype was 24.6%, and it had a unique sex and ethnic distribution. Polymorphism in the promoter region of TYMS gene that predicts decreased TS expression due to 2R/2R variant was associated with grade 3-4 FrAEs. These data suggest that genotyping patients who are not DPD deficient for TYMS might identify patients at risk of severe FrAEs.

Dipeptidyl peptidase IV is a human and murine neutrophil chemorepellent.

In Dictyostelium discoideum, AprA is a secreted protein that inhibits proliferation and causes chemorepulsion of Dictyostelium cells, yet AprA has little sequence similarity to any human proteins. We found that a predicted structure of AprA has similarity to human dipeptidyl peptidase IV (DPPIV). DPPIV is a serine protease present in extracellular fluids that cleaves peptides with a proline or alanine in the second position. In Insall chambers, DPPIV gradients below, similar to, and above the human serum DPPIV concentration cause movement of human neutrophils away from the higher concentration of DPPIV. A 1% DPPIV concentration difference between the front and back of the cell is sufficient to cause chemorepulsion. Neutrophil speed and viability are unaffected by DPPIV. DPPIV inhibitors block DPPIV-mediated chemorepulsion. In a murine model of acute respiratory distress syndrome, aspirated bleomycin induces a significant increase in the number of neutrophils in the lungs after 3 d. Oropharyngeal aspiration of DPPIV inhibits the bleomycin-induced accumulation of mouse neutrophils. These results indicate that DPPIV functions as a chemorepellent of human and mouse neutrophils, and they suggest new mechanisms to inhibit neutrophil accumulation in acute respiratory distress syndrome.

Overexpression of miR-122 promotes the hepatic differentiation and maturation of mouse ESCs through a miR-122/FoxA1/HNF4a-positive feedback loop.

BACKGROUND & AIMS: microRNA-122 is the only identified liver-specific miRNA and plays a crucial role in liver development, maintenance of hepatic homeostasis as well as tumourigenesis. In our previous differentiation of ESCs into hepatocytes, microRNA-122 (miR-122) was expressed at a relatively low level. Here, we aim to elucidate the effect and underlying mechanisms of miR-122 during differentiation of ESCs into hepatocytes. METHODS: Mouse ESCs were initially induced towards HPCs by activin A, FGF-4 and sodium butyrate and were subsequently transfected with a recombinant adenovirus expressing vector pAV.Ex1d-CMV>miR-122/IRES/eGFP 9 days after induction. Cells were analysed by real-time PCR, immunofluorescence, flow cytometry, microscopy and functional assays. Furthermore, microarray analysis was performed. RESULTS: We demonstrated that overexpression of miR-122 could effectively promote hepatic differentiation and maturation, as assessed by morphological and functional tests. The microarray analysis revealed that 323 genes were down-regulated, whereas 59 were up-regulated. Particularly, two liver-specific transcription factors, FoxA1 and HNF4a, were significantly up-regulated. Moreover, the expression of E-cadherin was dramatically increased and the proliferation of HPCs was suppressed, whereas knockdown of FoxA1 reduced E-cadherin expression and increased the proliferation of HPCs. In addition, the expression levels of FoxA1, HNF4a and E-cadherin in time-course transfection experiments with miR-122 were not significantly increased except in cells in which transfection with miR-122 occurred 9 days after induction. CONCLUSION: Overexpression of miR-122 at an appropriate stage could promote hepatic differentiation and maturation by regulating the balance between proliferation and differentiation, as well as the balance between EMT and MET, partially through a miR-122/FoxA1/HNF4a-positive feedback loop.

Absence of Anti-Babesia microti antibody in commercial intravenous immunoglobulin (IVIG).

BACKGROUND: Babesiosis is a worldwide emerging protozoan infection that is associated with a spectrum of disease severity from asymptomatic infection to severe organ damage and death. While effective treatment strategies are available, some immunocompromised patients experience severe acute and prolonged/relapsing illness due in part to an impaired host antibody response. Intravenous immunoglobulin (IVIG) has been used as an adjunctive therapy in some immunocompromised babesiosis patients, but its therapeutic effect is uncertain. We evaluated the presence of Babesia microti antibodies in commercial samples of IVIG. METHODS/PRINCIPLE FINDINGS: The presence of B. microti antibodies in commercial samples of IVIG were tested using an immunofluorescence assay. A subset of samples was then tested for B. microti antibodies using an enzyme linked immunosorbent assay. Out of 57 commercial IVIG samples tested using IFA, and 52 samples tested using ELISA, none were positive for B. microti antibodies. CONCLUSIONS: Commercially available IVIG may not be of therapeutic benefit for babesiosis patients. Additional sampling of IVIG for B. microti antibody and a clinical trial of babesiosis patients given IVIG compared with controls would provide further insight into the use of IVIG for the treatment of babesiosis.

RNA folding in transcription elongation complex: implication for transcription termination.

Intrinsic transcription termination signal in DNA consists of a short inverted repeat followed by a T-rich stretch. Transcription of this sequence by RNA polymerase (RNAP) results in formation of a "termination hairpin" (TH) in the nascent RNA and in rapid dissociation of the transcription elongation complex (EC) at termination points located 7-8 nt downstream of the base of TH stem. RNAP envelops 15 nt of the RNA following RNA growing 3'-end, suggesting that folding of the TH is impeded by a tight protein environment when RNAP reaches the termination points. To monitor TH folding under this constraint, we halted Escherichia coli ECs at various distances downstream from a TH and treated them with single-strand specific RNase T1. The EC interfered with TH formation when halted at 6, 7, and 8, but not 9, nt downstream from the base of the potential stem. Thus, immediately before termination, the downstream arm of the TH is protected from complementary interactions with the upstream arm. This protection makes TH folding extremely sensitive to the sequence context, because the upstream arm easily engages in competing interactions with the rest of the nascent RNA. We demonstrate that by de-synchronizing TH formation and transcription of the termination points, this subtle competition significantly affects the efficiency of transcription termination. This finding can explain previous puzzling observations that sequences far upstream of the TH or point mutations in the terminator that preserve TH stability affect termination. These results can help understand other time sensitive co-transcriptional processes in pro- and eukaryotes.

A modified laparoscopic splenectomy for massive splenomegaly in children with hematological disorder: a single institute retrospective clinical research.

PURPOSE: With the optimal acceptance of its clinical advantages, laparoscopic splenectomy (LS) emerged as a gold standard procedure as compared with open splenectomy (OS). However, it is still controversial and even counted as contraindication for massive splenomegaly. Here, we aim to summarize the experiences, characteristics and trends of modified LS for massive splenomegaly in children with hematological disorders. METHODS: Retrospective series of 57 pediatric patients with massive splenomegaly who underwent splenectomy from March 2007 to December 2011 were designated for this clinical analysis. The main outcome measures were dealt by statistics. For 30 cases of LS, we strictly adhered to the principle of using only three trocars to operate and initial ligation of the splenic artery, followed by retrieving the piecemeal of spleen through an accessory incision of 2-3 cm at 12 mm trocar port site. RESULTS: Of the 57 pediatric patients, 27 underwent OS and 30 underwent LS, respectively. Despite the operative time being shorter for OS than for LS (P < 0.001), the blood loss was lower in LS than in OS (P < 0.001); the time required for oral intake as well as duration of hospital stay was lower in LS than in OS (P < 0.001). Post-operatively, 7 (25.9 %) complications occurred in OS and 3 (10 %) in LS. The conversion rate of LS to OS was 13.33 % in four cases till 2009. CONCLUSIONS: Despite the conflicting reports regarding the safety of LS for massive splenomegaly, we demonstrated that our modified laparoscopic splenectomy in the treatment of children with massive splenomegaly in hematological diseases seemed to achieve the fundamental goal of less invasion; it was safe and feasible.

Antimicrobial Susceptibility Pattern of Salmonella spp. Isolated from Enteric Fever Patients in Nepal.

INTRODUCTION: Enteric fever, a systemic infection caused by Salmonella enterica Typhi and S. enterica Paratyphi is one of the most common infections in developing countries such as Nepal. Aside from irrational practices of antibiotic use, mutations in chromosomal genes encoding DNA gyrase and Topoisomerase IV and by plasmid mediated quinolone resistant (PMQR) genes are suggested mechanisms for the development of resistance to nalidixic acid and reduced susceptibility to ciprofloxacin. Regardless of high endemicity of enteric fever in Nepal, there is paucity of studies on prevalence and drug-resistance of the pathogen. Therefore, this study aimed to assess the antibiotic susceptibility pattern of Salmonella isolates and determine the minimum inhibitory concentration of ciprofloxacin. METHODS: A total of 1298 blood samples were obtained from patients with suspected enteric fever, attending Sukraraj Tropical and Infectious Disease Hospital (STIDH) during March-August, 2019. Blood samples were inoculated immediately into BACTEC culture bottles and further processed for isolation and identification of Salmonella Typhi and S. Paratyphi. Axenic cultures of the isolates were further subjected to antimicrobial susceptibility testing (AST) by using the modified Kirby-Bauer disc diffusion method based on the guidelines by CLSI. The minimum inhibitory concentration (MIC) of ciprofloxacin was determined by agar-dilution method. RESULTS: Out of 1298 blood cultures, 40 (3.1%) were positive for Salmonella spp. among which 29 (72.5%) isolates were S. Typhi and 11 (27.5%) isolates were S. Paratyphi A. In AST, 12.5% (5/40), 15% (6/40) and 20% (8/40) of the Salmonella isolates were susceptible to nalidixic acid, ofloxacin and levofloxacin, respectively, whereas none of the isolates were susceptible to ciprofloxacin. The MIC value for ciprofloxacin ranged from 0.06-16 µg/mL in which, respectively, 5% (2/40) and 52.5% (21/40) of the isolates were susceptible and resistant to ciprofloxacin. None of the isolates showed multidrug-resistance (MDR) in this study. CONCLUSION: This study showed high prevalence of quinolone-resistant Salmonella spp., while there was marked re-emergence of susceptibilities to traditional first option drugs. Hence, conventional first-line-drugs and third-generation cephalosporins may find potential usage as the empirical drugs for enteric fever. Although our reporting was free of MDR strains, extensive surveillance, augmentation of diagnostic facilities and treatment protocol aided by AST report are recommended for addressing the escalating drug-resistance in the country.

High Resistance of Salmonella spp. and Shigella spp. in Blood and Stool Cultures from the Sukraraj Tropical and Infectious Disease Hospital, Kathmandu, Nepal, 2015-2019.

Antimicrobial resistance (AMR) is an increasing global concern, particularly in Southeast Asian countries like Nepal. The aim of this study was to determine the proportion of Salmonella spp. and Shigella spp. among culture-positive bacterial isolates in blood and stool samples from 2015 to 2019 and their AMR pattern. Routinely collected data were abstracted from medical records and laboratory electronic databases of the Sukraraj Tropical and Infectious Disease Hospital (STIDH), Kathmandu, Nepal. All culture-positive bacterial isolates from blood and stool samples were included in the study. Among 390 blood cultures positive for bacterial isolates, Salmonella spp. were isolated in 44%, with S. Typhi being the most frequent (34%). Antibiotic resistance was demonstrated among Salmonella spp. to ciprofloxacin (68%), ofloxacin (16%), amoxicillin (13%) and cotrimoxazole (5%). Of the 357 stool cultures positive for bacterial isolates, the proportion of Shigella spp. isolated was 31%. Antibiotic resistance among Shigella spp. was demonstrated to cotrimoxazole (59%), tetracycline (40%), amoxicillin (38%) and ciprofloxacin (25%). Salmonella spp. and Shigella spp. were the most predominant organisms among all the bacterial isolates in blood and stool cultures, respectively. Nalidixic acid was the antibiotic to which both Salmonella spp. and Shigella spp. were most resistant.

Congenital Tracheoesophageal Fistula in Very Low Birth Weight Preterm Neonate with an Oligohydramnios as a Rare Presentation: A Case Report.

Tracheoesophageal fistula is a challenging anomaly with a rare prevalence with symptoms mainly respiratory, sometimes digestive. We present a rare case of oesophageal atresia with distal Tracheoesophageal fistula in a female child whose mother presented with severe oligohydramnios on ultrasonography with intrauterine growth retardation before cesarean section. After the birth of preterm and very low birth weight neonate, we initially diagnosed as respiratory distress syndrome with a club foot. However, we diagnosed oesophageal atresia with distal Tracheoesophageal fistula on the 2nd day as nasogastric tube insertion was failed beyond 10cm and confirmed by X-ray with a rubber catheter. Right thoracotomy with ligation of the fistula with end to end anastomosis was performed successfully without complications. Breastfeeding initiated and the child discharged after she started gaining weight. Early post-operation complication (anastomotic stricture) was noticed after 2 weeks; however, corrected with endoscopic balloon dilatation. Currently, the child is healthy weighing 10kgs at 18 months of age.

Detection and characterization of estradiol (E2) and unconjugated estriol (uE3) immunoassay interference due to anti-bovine alkaline phosphatase (ALP) antibodies.

OBJECTIVES: Competitive immunoenyzmatic assays for estradiol (E2) and unconjugated estriol (uE3) on UniCel DxI 800 Access immunoassay systems (Beckman Coulter) utilize bovine alkaline phosphatase (ALP) for amplification. In these assays, rare 'IND' error flags indicate that a relative light unit (RLU) raw result is past the high or low end of the calibration curve but cannot be differentiated from an instrument error or analytical interference. The present studies were conducted to establish a protocol to identify analytical interference and to characterize its mechanism when present. DESIGN AND METHODS: Matrix and recovery studies were conducted to establish a protocol for interference identification. Spiking experiments with inactivated calf intestinal ALP were performed to determine whether interference could be blocked. Commercial anti-ALP antibodies (Abs) were spiked into human serum to model assay interference. Three E2 immunoassays which do not include ALP as a reagent component (cobas e602, Roche; Centaur XP, Siemens; ARCHITECT i2000SR, Abbott) were tested for comparative purposes. RESULTS: 1:2 dilution of specimen into Access Sample Diluent A (Beckman) differentiated IND error flags due to true low results (e.g. less than the analytical measurement range; AMR) from those due to assay interference. Interferences were reduced by pre-incubation with inactivated ALP and could be replicated by spiking with commercial anti-ALP Abs. CONCLUSIONS: Patient anti-bovine ALP Abs can cause interference on DxI 800 E2 and uE3 assays. This model can be used to investigate interference risk with other ALP-dependent assays.

The Prevalence of DPYD*9A(c.85T>C) Genotype and the Genotype-Phenotype Correlation in Patients with Gastrointestinal Malignancies Treated With Fluoropyrimidines: Updated Analysis.

INTRODUCTION: The dihydropyrimidine dehydrogenase gene (DPYD)*9A (c.85T>C) genotype is relatively common. The correlation between DPYD*9A genotype and dihydropyrimidine dehydrogenase (DPD) deficiency phenotype is controversial. In a cohort of 28 patients, DPYD*9A was the most commonly diagnosed variant (13 patients [46%]) and there was a noticeable genotype-phenotype correlation. In this study we genotyped a larger cohort of a mixed racial background to explore the prevalence of DPYD*9A variant and to confirm the genotype-phenotype correlation. PATIENTS AND METHODS: Between 2011 and 2018, in addition to genotyping for high-risk DPYD variants (DPYD*2A, DPYD*13 and DPYD*9B), genotyping for DPYD*9A variant was performed on 113 patients with gastrointestinal malignancies treated with fluoropyrimidines. Fluoropyrimidines-associated toxicity was graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events (version 5.0). Fisher exact test was used for statistical analysis. RESULTS: Heterozygous and homozygous DPYD*9A genotypes were identified in 46 (41%) and 11 (10%) patients, respectively. Among patients with DPYD*9A genotypes (n = 57), men and women represented 30 (53%) and 27 (47%) patients, respectively. Caucasian, African American, and other ethnicities represented 29 (50.9%), 26 (45.6%), and 2 (3.5%) patients, respectively. Grade 3/4 toxicities were experienced in 26 patients with DPYD*9A genotype (3 patients had homozygous status) and in 20 patients with wild type DPYD*9A (P = .4405). In patients who received full-dose fluoropyrimidines (n = 85), Grade 3/4 toxicities were experienced in 22 patients with DPYD*9A genotype (2 patients had homozygous status), and in 17 patients with wild type DPYD (P = .8275). CONCLUSION: In our updated analysis, the prevalence of heterozygous and homozygous DPYD*9A genotypes were 41% and 10%, respectively. The correlation between DPYD*9A genotype and DPD clinical phenotype was not reproduced. The noticeable correlation that we previously reported is likely because of small sample size and selection bias.

Characterizing the inflammatory response in esophageal mucosal biopsies in children with eosinophilic esophagitis.

Eosinophilic esophagitis (EoE) is an emerging allergic, IgE- and non-IgE (Th2 cell)-mediated disease. There are major gaps in the understanding of the basic mechanisms that drive the persistence of EoE. We investigated whether esophageal biopsies from children with EoE demonstrate an inflammatory response that is distinct from normal controls. We prospectively enrolled 84 patients, of whom 77 were included in our analysis, aged 4-17 years (12.8±3.8 years; 81% males). Five esophageal biopsies were collected from each patient at the time of endoscopy. Intramucosal lymphocytes were isolated, phenotyped and stimulated with phorbol 12-myristate 13-acetate/ionomycin to measure their potential to produce cytokines via flow cytometry. We also performed cytokine arrays on 72-h biopsy culture supernatants. CD8(+) T cells, compared with CD4(+) T cells, synthesized more TNF-α and interferon (IFN)-γ after mitogen stimulation in the EoE-New/Active vs EoE-Remission group (P=0.0098; P=0.02) and controls (P=0.0008; P=0.03). Culture supernatants taken from explant esophageal tissue contained 13 analytes that distinguished EoE-New/Active from EoE-Remission and Controls. Principal component analysis and cluster analysis based on these analytes distinctly separated EoE-New/Active from EoE-Remission and Controls. In summary, we have identified a previously unappreciated role for CD8(+) T lymphocytes with potential to produce TNF-α and IFN-γ in EoE. Our results suggest that CD8(+) T cells have a role in the persistence or progression of EoE. We have also identified a panel of analytes produced by intact esophageal biopsies that differentiates EoE-New/Active from EoE-Remission and controls. Our results suggest that esophageal epithelial cells may have specific immune effector functions in EoE that control the type and amplitude of inflammation.

Serum amyloid P inhibits granulocyte adhesion.

BACKGROUND: The extravasation of granulocytes (such as neutrophils) at a site of inflammation is a key aspect of the innate immune system. Signals from the site of inflammation upregulate granulocyte adhesion to the endothelium to initiate extravasation, and also enhance granulocyte adhesion to extracellular matrix proteins to facilitate granulocyte movement through the inflamed tissue. During the resolution of inflammation, other signals inhibit granulocyte adhesion to slow and ultimately stop granulocyte influx into the tissue. In a variety of inflammatory diseases such as acute respiratory distress syndrome, an excess infiltration of granulocytes into a tissue causes undesired collateral damage, and being able to reduce granulocyte adhesion and influx could reduce this damage. RESULTS: We found that serum amyloid P (SAP), a constitutive protein component of the blood, inhibits granulocyte spreading and granulocyte adhesion to extracellular matrix components. This indicates that in addition to granulocyte adhesion inhibitors that are secreted during the resolution of inflammation, a granulocyte adhesion inhibitor is present at all times in the blood. Although SAP affects adhesion, it does not affect the granulocyte adhesion molecules CD11b, CD62L, CD18, or CD44. SAP also has no effect on the production of hydrogen peroxide by resting or stimulated granulocytes, or N-formyl-methionine-leucine-phenylalanine (fMLP)-induced granulocyte migration. In mice treated with intratracheal bleomycin to induce granulocyte accumulation in the lungs, SAP injections reduced the number of granulocytes in the lungs. CONCLUSIONS: We found that SAP, a constitutive component of blood, is a granulocyte adhesion inhibitor. We hypothesize that SAP allows granulocytes to sense whether they are in the blood or in a tissue.

High and low molecular weight hyaluronic acid differentially regulate human fibrocyte differentiation.

BACKGROUND: Following tissue injury, monocytes can enter the tissue and differentiate into fibroblast-like cells called fibrocytes, but little is known about what regulates this differentiation. Extracellular matrix contains high molecular weight hyaluronic acid (HMWHA; ∼2×10(6) Da). During injury, HMWHA breaks down to low molecular weight hyaluronic acid (LMWHA; ∼0.8-8×10(5) Da). METHODS AND FINDINGS: In this report, we show that HMWHA potentiates the differentiation of human monocytes into fibrocytes, while LMWHA inhibits fibrocyte differentiation. Digestion of HMWHA with hyaluronidase produces small hyaluronic acid fragments, and these fragments inhibit fibrocyte differentiation. Monocytes internalize HMWHA and LMWHA equally well, suggesting that the opposing effects on fibrocyte differentiation are not due to differential internalization of HMWHA or LMWHA. Adding HMWHA to PBMC does not appear to affect the levels of the hyaluronic acid receptor CD44, whereas adding LMWHA decreases CD44 levels. The addition of anti-CD44 antibodies potentiates fibrocyte differentiation, suggesting that CD44 mediates at least some of the effect of hyaluronic acid on fibrocyte differentiation. The fibrocyte differentiation-inhibiting factor serum amyloid P (SAP) inhibits HMWHA-induced fibrocyte differentiation and potentiates LMWHA-induced inhibition. Conversely, LMWHA inhibits the ability of HMWHA, interleukin-4 (IL-4), or interleukin-13 (IL-13) to promote fibrocyte differentiation. CONCLUSIONS: We hypothesize that hyaluronic acid signals at least in part through CD44 to regulate fibrocyte differentiation, with a dominance hierarchy of SAP>LMWHA≥HMWHA>IL-4 or IL-13.

Toll-like receptor 2 agonists inhibit human fibrocyte differentiation.

BACKGROUND: In healing wounds, some monocytes enter the wound and differentiate into fibroblast-like cells called fibrocytes. Since Toll-like receptors (TLRs) are present on monocytes, and pathogens that can infect a wound have and/or release TLR agonists, we examined whether TLR agonists affect fibrocyte differentiation. RESULTS: When human peripheral blood mononuclear cells (PBMCs) were cultured with TLR3, TLR4, TLR5, TLR7, TLR8 or TLR9 agonists, there was no significant effect on fibrocyte differentiation, even though enhanced extracellular tumor necrosis factor (TNF)-α accumulation and/or increased cell surface CD86 or major histocompatibility complex (MHC) class II levels were observed. However, all TLR2 agonists tested inhibited fibrocyte differentiation without any significant effect on cell survival. Adding TLR2 agonists to purified monocytes had no effect on fibrocyte differentiation. However, some TLR2 agonists caused PBMCs to secrete a factor that inhibits the differentiation of purified monocytes into fibrocytes. This factor is not interferon (IFN)-α, IFN-γ, interleukin (IL)-12, aggregated immunoglobulin G (IgG) or serum amyloid P (SAP), factors known to inhibit fibrocyte differentiation. TLR2 agonist-treated PBMCs secrete low levels of IL-6, TNF-α, IFN-γ, granulocyte colony-stimulating factor and tumor growth factor ß1, but combinations of these factors had no effect on fibrocyte differentiation from purified monocytes. CONCLUSIONS: Our results indicate that TLR2 agonists indirectly inhibit fibrocyte differentiation and that, for some TLR2 agonists, this inhibition involves other cell types in the PBMC population secreting an unknown factor that inhibits fibrocyte differentiation. Together, these data suggest that the presence of some bacterial signals can inhibit fibrocyte differentiation and may thus slow wound closure.