Follicular lymphoma tumor-infiltrating T-helper (T(H)) cells have the same polyfunctional potential as normal nodal T(H) cells despite skewed differentiation.

The follicular lymphoma (FL) T-cell microenvironment plays a critical role in the biology of this disease. We therefore determined the lineage, differentiation state, and functional potential of FL-infiltrating CD4(+) T-helper cells (T(H)) compared with reactive and normal lymph node (NLN) T(H) cells. Relative to NLNs, FL cells have decreased proportions of naive and central memory but increased proportions of effector memory T(H) cells. We further show differences in the distribution and anatomical localization of CXCR5(+) T(H) populations that, on the basis of transcription factor analysis, include both regulatory and follicular helper T cells. On Staphylococcus enterotoxin-B stimulation, which stimulates T cells through the T-cell receptor, requires no processing by APCs, and can overcome regulator T cell-mediated suppression, the proportion of uncommitted primed precursor cells, as well as T(H)2 and T(H)17 cells is higher in FL cells than in reactive lymph nodes or NLNs. However, the proportion of T(H)1 and polyfunctional T(H) cells (producing multiple cytokines simultaneously) is similar in FL cells and NLNs. These data suggest that, although T(H)-cell differentiation in FL is skewed compared with NLNs, FL T(H) cells should have the same intrinsic ability to elicit antitumor effector responses as NLN T(H) cells when tumor suppressive mechanisms are attenuated.

Guidance for isolation precautions for mumps in the United States: a review of the scientific basis for policy change.

The 2006 mumps resurgence in the United States raised questions about the appropriate isolation period for people with mumps. To determine the scientific basis for isolation recommendations, we conducted a literature review and considered isolation of virus and virus load in saliva and respiratory secretions as factors that were related to mumps transmission risk. Although mumps virus has been isolated from 7 days before through 8 days after parotitis onset, the highest percentage of positive isolations and the highest virus loads occur closest to parotitis onset and decrease rapidly thereafter. Most transmission likely occurs before and within 5 days of parotitis onset. Transmission can occur during the prodromal phase and with subclinical infections. Updated guidance, released in 2007-2008, changed the mumps isolation period from 9 to 5 days. It is now recommended that mumps patients be isolated and standard and droplet precautions be followed for 5 days after parotitis onset.

Guidelines for the Prevention and Treatment of Opportunistic Infections among HIV-exposed and HIV-infected children: recommendations from CDC, the National Institutes of Health, the HIV Medicine Association of the Infectious Diseases Society of America, the Pediatric Infectious Diseases Society, and the American Academy of Pediatrics.

This report updates and combines into one document earlier versions of guidelines for preventing and treating opportunistic infections (OIs) among HIV-exposed and HIV-infected children, last published in 2002 and 2004, respectively. These guidelines are intended for use by clinicians and other health-care workers providing medical care for HIV-exposed and HIV-infected children in the United States. The guidelines discuss opportunistic pathogens that occur in the United States and one that might be acquired during international travel (i.e., malaria). Topic areas covered for each OI include a brief description of the epidemiology, clinical presentation, and diagnosis of the OI in children; prevention of exposure; prevention of disease by chemoprophylaxis and/or vaccination; discontinuation of primary prophylaxis after immune reconstitution; treatment of disease; monitoring for adverse effects during treatment; management of treatment failure; prevention of disease recurrence; and discontinuation of secondary prophylaxis after immune reconstitution. A separate document about preventing and treating of OIs among HIV-infected adults and postpubertal adolescents (Guidelines for the Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents) was prepared by a working group of adult HIV and infectious disease specialists. The guidelines were developed by a panel of specialists in pediatric HIV infection and infectious diseases (the Pediatric Opportunistic Infections Working Group) from the U.S. government and academic institutions. For each OI, a pediatric specialist with content-matter expertise reviewed the literature for new information since the last guidelines were published; they then proposed revised recommendations at a meeting at the National Institutes of Health (NIH) in June 2007. After these presentations and discussions, the guidelines underwent further revision, with review and approval by the Working Group, and final endorsement by NIH, CDC, the HIV Medicine Association (HIVMA) of the Infectious Diseases Society of America (IDSA), the Pediatric Infectious Disease Society (PIDS), and the American Academy of Pediatrics (AAP). The recommendations are rated by a letter that indicates the strength of the recommendation and a Roman numeral that indicates the quality of the evidence supporting the recommendation so readers can ascertain how best to apply the recommendations in their practice environments. An important mode of acquisition of OIs, as well as HIV infection among children, is from their infected mother; HIV-infected women coinfected with opportunistic pathogens might be more likely than women without HIV infection to transmit these infections to their infants. In addition, HIV-infected women or HIV-infected family members coinfected with certain opportunistic pathogens might be more likely to transmit these infections horizontally to their children, resulting in increased likelihood of primary acquisition of such infections in the young child. Therefore, infections with opportunistic pathogens might affect not just HIV-infected infants but also HIV-exposed but uninfected infants who become infected by the pathogen because of transmission from HIV-infected mothers or family members with coinfections. These guidelines for treating OIs in children therefore consider treatment of infections among all children, both HIV-infected and uninfected, born to HIV-infected women. Additionally, HIV infection is increasingly seen among adolescents with perinatal infection now surviving into their teens and among youth with behaviorally acquired HIV infection. Although guidelines for postpubertal adolescents can be found in the adult OI guidelines, drug pharmacokinetics and response to treatment may differ for younger prepubertal or pubertal adolescents. Therefore, these guidelines also apply to treatment of HIV-infected youth who have not yet completed pubertal development. Major changes in the guidelines include 1) greater emphasis on the importance of antiretroviral therapy for preventing and treating OIs, especially those OIs for which no specific therapy exists; 2) information about the diagnosis and management of immune reconstitution inflammatory syndromes; 3) information about managing antiretroviral therapy in children with OIs, including potential drug--drug interactions; 4) new guidance on diagnosing of HIV infection and presumptively excluding HIV infection in infants that affect the need for initiation of prophylaxis to prevent Pneumocystis jirovecii pneumonia (PCP) in neonates; 5) updated immunization recommendations for HIV-exposed and HIV-infected children, including hepatitis A, human papillomavirus, meningococcal, and rotavirus vaccines; 6) addition of sections on aspergillosis; bartonella; human herpes virus-6, -7, and -8; malaria; and progressive multifocal leukodystrophy (PML); and 7) new recommendations on discontinuation of OI prophylaxis after immune reconstitution in children. The report includes six tables pertinent to preventing and treating OIs in children and two figures describing immunization recommendations for children aged 0--6 years and 7--18 years. Because treatment of OIs is an evolving science, and availability of new agents or clinical data on existing agents might change therapeutic options and preferences, these recommendations will be periodically updated and will be available at http://AIDSInfo.nih.gov.

Targeting 11q23 positive acute leukemia cells with high molecular weight-melanoma associated antigen-specific monoclonal antibodies.

BACKGROUND: Acute leukemia with 11q23 aberrations is associated with a poor outcome with therapy. The lack of efficacy of conventional therapy has stimulated interest in developing novel strategies. Recent studies have shown that 11q23-positive acute leukemia cells express the high molecular weight-melanoma associated antigen (HMW-MAA). This tumor antigen represents a useful target to control growth of human melanoma tumors in patients and in severe combined immunodeficient (SCID) mice, utilizing antibody-based immunotherapy. This effect appears to be mediated by inhibition of the HMW-MAA function such as triggering of the focal adhesion kinase/proline-rich tyrosine kinase 2 (Pyk2) pathways. Therefore, in this study we tested whether HMW-MAA-specific monoclonal antibodies (mAb) could inhibit growth of 11q23-positive leukemia cells in SCID mice. METHODS: HMW-MAA-specific mAb were tested for their ability to inhibit the in vitro proliferation of an 11q23-positive acute myeloid leukemia (AML) cell line and blasts from four patients with 11q23 aberrations and their in vivo growth in subcutaneous and disseminated xenograft models. RESULTS: The HMW-MAA-specific mAb did not affect in vitro proliferation although they down-regulated phosphorylated (P) Pyk2 expression. Furthermore, the mAb enhanced the in vitro anti-proliferative effect of cytarabine. In vivo the mAb inhibited the growth of leukemic cells in a dose-dependent fashion. However, the difference did not reach statistical significance. No effect was detected on P-Pyk2 expression. Furthermore, HMW-MAA-specific mAb in combination with cytarabine did not improve tumor inhibition. Lastly, the combination of two mAb which recognize distinct HMW-MAA determinants had no detectable effect on survival in a disseminated xenograft model. CONCLUSIONS: HMW-MAA-specific mAb down-regulated P-Pyk2 expression and enhanced the anti-proliferative effect of cytarabine in vitro, but had no detectable effect on survival or growth of leukemia cells in vivo. Whether the HMW-MAA-specific mAb can be used as carriers of toxins or chemotherapeutic agents against 11q23-acute leukemia remains to be determined.

Synergism between arsenic trioxide and heat shock protein 90 inhibitors on signal transducer and activator of transcription protein 3 activity--pharmacodynamic drug-drug interaction modeling.

PURPOSE: Constitutive signal transducer and activator of transcription 3 (STAT3) activity, observed in approximately 50% of acute myelogenous leukemia cases and associated with adverse treatment outcome, is down-regulated by arsenic trioxide (ATO). Heat shock protein (HSP) 90 is a molecular chaperone involved in signal transduction pathways. We hypothesized that HSP90 inhibitors will potentiate ATO effect on constitutive STAT3 activity and cell killing. One concern was that the effect of ATO and HSP90 inhibitors will result in up-regulation of HSP70, a protein known to inhibit apoptosis. EXPERIMENTAL DESIGN: We have used a semimechanistic pharmacodynamic model to characterize concentration-effect relationships of ATO and HSP90 inhibitors on constitutive STAT3 activity, HSP70 expression, and cell death in a cell line model. RESULTS: Pharmacodynamic interaction of ATO and three HSP90 inhibitors showed synergistic interactions in inhibiting constitutive STAT3 activity and inducing cell death, in spite of a concurrent synergistic up-regulation of HSP70. CONCLUSIONS: These preliminary results provide a basis for studying the combined role of ATO with HSP90 inhibitors in acute myelogenous leukemia with constitutive STAT3 activity.

Do-not-resuscitate orders and/or hospice care, psychological health, and quality of life among children/adolescents with acquired immune deficiency syndrome.

OBJECTIVE: The frequency of do-not-resuscitate (DNR) orders and hospice enrollment in children/adolescents living with acquired immune deficiency syndrome (AIDS) and followed in Pediatric AIDS Clinical Trials Group (PACTG) Study 219C was examined, and evaluated for any association with racial disparities or enhanced quality of life (QOL), particularly psychological adjustment. METHODS: A cross-sectional analysis of children with AIDS enrolled in this prospective multicenter observational study between 2000 and 2005 was conducted to evaluate the incidence of DNR/hospice overall and by calendar time. Linear regression models were used to compare caregivers' reported QOL scores within 6 domains between those with and without DNR/hospice care, adjusting for confounders. RESULTS: Seven hundred twenty-six (726) children with AIDS had a mean age of 12.9 years (standard deviation [SD]=4.5), 51% were male, 60% black, 25% Hispanic. Twenty-one (2.9%) had either a DNR order (n=16), hospice enrollment (n=7), or both (n=2). Of 41 children who died, 80% had no DNR/hospice care. Increased odds of DNR/hospice were observed for those with CD4% less than 15%, no current antiretroviral use, and prior hospitalization. No differences by race were detected. Adjusted mean QOL scores were significantly lower for those with DNR/hospice enrollment than those without across all domains except for psychological status and health care utilization. Poorer psychological status correlated with higher symptom distress, but not with DNR/hospice enrollment after adjusting for symptoms. CONCLUSIONS: Children who died of AIDS rarely had DNR/hospice enrollment. National guidelines recommend that quality palliative care be integrated routinely with HIV care. Further research is needed to explore the barriers to palliative care and advance care planning in this population.

Arsenic trioxide affects signal transducer and activator of transcription proteins through alteration of protein tyrosine kinase phosphorylation.

PURPOSE: Arsenic trioxide decreases proliferation of acute myeloid leukemia (AML) cells, but its precise mechanism of action is unknown. EXPERIMENTAL DESIGN: We studied the effect of arsenic trioxide on patient samples and the AML cell line HEL, which, like leukemic blasts from 50% of AML cases, has constitutively activated signal transducer and activator of transcription (STAT) proteins. RESULTS: Arsenic trioxide induced mitotic arrest starting at 24 hours and significant cell death at 48 hours. These events were preceded by an arsenic trioxide dose-dependent down-regulation of activated STAT proteins starting at 6 hours. We hypothesized that arsenic trioxide inhibits protein tyrosine kinases (PTK), which, among others, phosphorylate and activate STATs. We therefore studied arsenic trioxide effects on Janus kinases and on three oncogenic PTKs that are known to activate STATs [FLT3, ZNF198/fibroblast growth factor receptor 1 (FGFR1), and BCR/ABL]. Arsenic trioxide reduced STAT3 activation by Janus kinases, altered phosphorylation and electrophoretic mobility of ZNF198/fibroblast growth factor receptor 1, reduced kinase protein level, and decreased STAT3 protein phosphorylation. Arsenic trioxide also reduced the phosphorylation of BCR/ABL and FLT3 with corresponding decreased STAT5 phosphorylation. CONCLUSIONS: These results suggest a selective activity of arsenic trioxide on PTKs and will assist in developing clinical trials in AML.

Extemporaneous sildenafil citrate oral suspensions for the treatment of pulmonary hypertension in children.

PURPOSE: The stability of sildenafil citrate 2.5 mg/mL in two extemporaneously prepared oral suspensions stored at 4 and 25 degrees C was studied. METHODS: Thirty 25-mg tablets of sildenafil citrate were ground to powder, and the powder was combined with a 1:1 mixture of Ora-Sweet and Ora-Plus or a 1:1 mixture of methylcellulose 1% and Simple Syrup, NF, to produce two 2.5-mg/mL suspensions. Five plastic bottles of each suspension were stored in amber plastic prescription bottles at 4 or 25 degrees C. Samples were collected on days 0, 7, 14, 28, 42, 56, 70, and 91 for analysis of sildenafil content by high-performance liquid chromatography; pH was also measured. Samples were visually observed against black and white backgrounds. RESULTS: The mean concentration of sildenafil citrate exceeded 98% of the initial concentration in all samples at both temperatures throughout the 91-day study period. No changes in pH, odor, or physical appearance were observed. CONCLUSION: Sildenafil citrate 2.5 mg/mL in two extemporaneously compounded oral suspensions was stable for 91 days in plastic prescription bottles at 4 and 25 degrees C.

Newborn Male Circumcision with Parental Consent, as Stated in the AAP Circumcision Policy Statement, Is Both Legal and Ethical.

Newborn male circumcision is a minor surgical procedure that has generated significant controversy. Accumulating evidence supports significant health benefits, most notably reductions in urinary tract infections, acquisition of HIV and a number of other sexually transmitted infections, penile cancer, phimosis, paraphimosis, balanitis and lichen sclerosis. While circumcision, like any surgical procedure, has risks for complications, they occur in less than 1 in 500 infants circumcised and most are minor and require minimal intervention. The CDC and the American Academy of Pediatrics (AAP) believe that health benefits of circumcision outweigh the risks. For this reason, the AAP believes that parents should be allowed to make the decision concerning circumcision of their male infants after receiving non-biased information on health risks and health benefits.

Long-term effects of protease-inhibitor-based combination therapy on CD4 T-cell recovery in HIV-1-infected children and adolescents.

BACKGROUND: There is limited evidence about longer-term effects of combination antiretroviral therapy that includes protease inhibitors (PIs) on the immunological status of HIV-1-infected children. Better understanding might help to resolve questions on when to initiate treatment. METHODS: The change in percentage of CD4-positive T lymphocytes (CD4%) was investigated in 1012 previously treated HIV-1-infected children (aged 0-17 years) who were enrolled in research clinics in the USA before 1996 and followed up to 2000. 702 started PI-based combination therapy. Data analyses ignored subsequent treatment changes. FINDINGS: Among the 1012 children, the median CD4% increased from 22% to 28% between 1996, when PIs were first prescribed, and 2000. For the 702 who started PI-based therapy, the mean CD4% increase after 3 years was largest among participants with the greatest immunosuppression (15.7%, 10.6%, 5.1%, and 2.0% for participants with CD4% before therapy of <5%, 5-14%, 15-24%, and >25%; p<0.0001). After adjustment for pre-PI CD4%, the mean increase was largest among the youngest participants (9.2%, 8.0%, and 4.3% for ages <5 years, 5-9 years, and >10 years; p=0.001). However, only a minority of significantly immunocompromised participants (33%, 26%, and 49% of those with pre-PI CD4% of <5%, 5-14%, or 15-24%) achieved CD4% values above 25%, whereas 84% of those with pre-PI values above 25% maintained such values. INTERPRETATION: Although PI-based therapy was associated with substantial improvements in CD4%, initiation before severe immunosuppression and at younger ages may be more effective for recovery or maintenance of normal CD4%. Randomised investigation of when to start combination therapy in children, particularly infants, is needed.

Infectious disease in pediatric out-of-home child care.

Provision of some form of child care outside of the home is certainly not a new phenomenon. In the past, most out-of-home care was provided by a relative, a friend, or someone who had a specific relationship with the family of the child. The frequency of utilization of child care centers for out-of-home care and the different formats of out-of-home care services has increased within recent decades and will vary by geographic location. Also, there is an increased utilization of temporary child care such as "mother's day out" or baby-sitting services provided at churches, grocery stores, and other places. Child care centers represent special risks for transmission of infectious agents because young children exhibit high susceptibility to many community-acquired viruses and bacteria; they lack developmental understanding required for good hygiene; and they frequently receive antibiotics (appropriately and inappropriately). Infections acquired in child care centers can significantly impact the health of the children who acquire the infection and also result in significant economic impacts on the child's family, particularly if 1 or more of the parents has to lose time from work. In the United States, it is estimated that families who have children in child care lose 13 days of work per year for all types of infections. Interventions that have proven valuable for reducing infections within child care centers include the following: (1) formal written policies for infection control within the child care center, (2) formal education of child care center staff concerning infection control practices (needs to be repeated; preferably on a recurring basis), (3) good hand hygiene by both staff and children, (4) appropriate cleaning of contaminated surfaces, (5) separation of food preparation and diaper changing, (6) exclusion of certain ill children, (7) cohorting ill children when exclusion is not possible, (8) ensuring adequate age-appropriate immunization of child care attendees and staff, and (9) optimal ratios of children to staff.

Health care-associated infections in the neonatal intensive care unit.

Neonates represent a unique and highly vulnerable patient population. Advances in medical technology that have occurred over the last few decades have improved the survival and quality of life for neonates, particularly those infants born with extreme prematurity or with congenital defects. Although immunologic immaturity and altered cutaneous barriers play some role in the vulnerability of neonates to nosocomial infections, clearly, therapeutic interventions that have proven to be lifesaving for these fragile infants also appear to be associated with the majority of infectious complications resulting in neonatal morbidity and mortality. Rates of infections in neonatal intensive care units (NICUs) have varied from 6% to 40% of neonatal patients, with the highest rates in those facilities having larger proportions of very low-birth-weight infants (birthweight < or =1000 grams) or neonates requiring surgery. Efforts to protect the vulnerable NICU infants include the following: (1) optimal infection control practices, especially good hand hygiene and good nursery design; (2) prudent use of invasive interventions with particular attention to early removal of invasive devices after they are no longer essential; and (3) judicious use of antimicrobial agents, with an emphasis on targeted (narrow spectrum) rather than broad-spectrum antibiotics and appropriate indications (proven or suspected bacterial infections).

Third-trimester maternal toxicity with nevirapine use in pregnancy.

OBJECTIVE: Nevirapine-based therapy is associated with increased frequency of adverse events among women with CD4+ cell count of 250 cells/microL or greater. We evaluated the safety of nevirapine-based antiretroviral therapy in human immunodeficiency virus (HIV)-1-infected pregnant women. METHODS: We retrospectively evaluated 23 pregnancies managed with nevirapine-based regimens from July 2001 to April 2005. The incidence of adverse events was determined and analyzed by CD4+ cell count of either less than or greater than or equal to 250 cells/microL, and gestational age when nevirapine was initiated. Liver function abnormality was graded according to the National Institute of Allergy and Infectious Diseases Division of AIDS toxicity guidelines. RESULTS: Five of 23 patients (21.7%) started nevirapine-based therapy after 27 weeks of gestation. All 3 cases of adverse events occurred in this group within 6 weeks of initiating therapy and with CD4+ cell count greater than 250 cells/microL. A significant difference was noted in the proportion of patients who developed toxicity while starting nevirapine in the third trimester (3/5, 60%; 95% confidence interval 14.66-94.73) compared with those starting nevirapine earlier in pregnancy (0/18, 0%; 95% confidence interval 0.0-18.53; P < .006). Two patients developed rash, eosinophilia, and liver function abnormality, with one developing clinical hepatitis and renal failure. A third patient had abnormal elevation of liver enzymes but was asymptomatic. CONCLUSION: The incidence of adverse events with nevirapine may be lower than previously reported (13% versus 29%) and may be primarily noted with initiating the drug late in pregnancy. Further study of nevirapine in larger cohorts of HIV-infected pregnant women is warranted to determine the relationship between nevirapine hepatotoxicity and trimester use. LEVEL OF EVIDENCE: II-3.

Mesenchymal stromal cells support the viability and differentiation of follicular lymphoma-infiltrating follicular helper T-cells.

The biology of follicular lymphoma (FL) is largely dictated by the immune-effector and stromal cells that comprise its tumor microenvironment. FL-infiltrating T-cell populations that are thought to be fundamental to FL biology are follicular helper T-cells (TFH), follicular regulatory T-cells (TFR), a recently described population that regulates TFH activity, and regulatory T-cells (Treg). These T-cell populations have dynamic interactions with mesenchymal stromal cells (MSCs) in the tumor microenvironment. Whereas MSCs have been shown to support FL B-cell and Treg viability, their effects on FL-infiltrating TFH and TFR cells have not been described. Herein we show that MSCs support the viability of FL-infiltrating TFH and TFR, as well as Tregs, in part through an IL-6-dependent mechanism. We further demonstrate that MSCs mediate TFH to TFR conversion by inducing the expression of FoxP3 in TFH cells, demonstrating for the first time that human TFR can be derived from TFH cells. Given that the balance of TFH and TFR populations likely dictate, in part, the biology of this disease, our data support the potential for targeting MSCs as a therapeutic strategy.

Down-regulation of signal transducer and activator of transcription 3 improves human acute myeloid leukemia-derived dendritic cell function.

Signal transducer and activator of transcription (STAT) 3 inhibits dendritic cell (DC) differentiation and is constitutively activated in blasts of approximately half of AML patients. We investigated the correlation between STAT3 activity, DC maturation and the ability to stimulate T-cells in primary acute myeloid leukemia (AML)-derived DCs. STAT3 knock-down by shRNAmir increased the ability of AML-DCs to stimulate T-cells. Treatment of AML-DC with arsenic trioxide, but not AG490, JSI-124 or NSC-74859, led to a more mature phenotype and enhanced T-cell stimulation, while having minimal effect on normal DC. We conclude that AML-DCs have improved immunogenicity after reducing STAT3.

Epidemiology and diagnosis of health care-associated infections in the NICU.

Health care-associated infections in the NICU are a major clinical problem resulting in increased morbidity and mortality, prolonged length of hospital stays, and increased medical costs. Neonates are at high risk for health care-associated infections because of impaired host defense mechanisms, limited amounts of protective endogenous flora on skin and mucosal surfaces at time of birth, reduced barrier function of neonatal skin, the use of invasive procedures and devices, and frequent exposure to broad-spectrum antibiotics. This statement will review the epidemiology and diagnosis of health care-associated infections in newborn infants.