BACKGROUND: Defects of myeloid (m) dendritic cells (DC) and plasmacytoid (p) DC have been described in HIV infection. Following potent ART, mDC become normal but pDC defects persist. The status of DC in perinatally HIV-infected subjects who have survived into late childhood and adolescence with ART is unknown. We hypothesized that persistent pDC defects could be associated with impaired immune reconstitution or virologic failure on ART. METHODS: Subjects with perinatal HIV infection (n=18, median age 13.2 years), of whom 14 were on ART for >5 years (median 9.9 years), and 4 for <5 years (median 2.5 years), were classified as immunologic responders (IR+; CD4 >25%), or virologic responders (VR+; plasma HIV RNA <400 copies/mL). As controls, 5 healthy age- matched subjects were studied. DC were defined as (Lin 1, HLA DR+) and subtyped as mDC (CD11c+) or pDC (CD123+). Short-term stimulation (3 hours) of mDC and pDC was performed through ligation of their toll-like receptors (TLR) with a TLR7/8 agonist (Resiquomod). DC maturation markers CD83, CD80, lymph node homing receptor CCR7, and intracellular cytokines tumor necrosis factor-α(TNF-α ) and interferon-α (IFN-α ), were evaluated by flow cytometry in a whole blood assay. Spearman correlation and Student's t tests were used as statistical tools. RESULTS: Upon TLR ligation, both subsets of DC showed marked up-regulation of CD83, and moderate increase in CD80 (mDC> pDC) in all study subjects. CCR7 up- regulation and IFN-αresponse occurred primarily in pDC, and TNF-αresponse was more pronounced in mDC than in pDC. A selective impairment in up-regulation of pDC CCR7 was observed in patients classified as IR and VR as compared with subjects who were classified as IR+VR+ (mean CCR7: 5.6% vs 43.3%, respectively; p=0.0002). Levels of pDC CCR7 were intermediate (mean 22.8%) in the IR+VR patient group. CCR7

A retrieval technique has been developed to simultaneously determine column ozone amounts and aerosol optical properties using surface observations of solar ultraviolet direct normal and diffuse horizontal irradiance from a multifilter rotating shadowband radiometer. The retrieval consists of a Bayesian scheme involving a tropospheric ultraviolet radiative transfer model. The technique was tested using cloud‐free observations collected during a Mexico City Metropolitan Area air pollution field campaign from April to May 2003. Retrieval results compared favorably to those of independent techniques, including ozone amounts from a direct‐Sun method, Langley‐derived aerosol optical depths, and aerosol single‐scattering albedos from a direct‐to‐diffuse irradiance ratio technique. Further comparisons were performed between the measurements and model simulations when using the retrieval results as inputs, both from the proposed technique and the combined independent methods. Simulations using the results of the new method were found to agree with the observations within the assumed limits of measurement and model uncertainty. It is anticipated that the technique will be applied across a 33‐site network of radiometers maintained by the U.S. Department of Agriculture UV‐B Monitoring and Research Program for development of aerosol climatologies and for providing ground validation for satellite measurements.

Compared to the visible spectral region, very little is known about aerosol absorption in the UV. Without such information it is impossible to quantify the causes of the observed discrepancy between modeled and measured UV irradiances and photolysis rates. We report results of a 17-month aerosol column absorption monitoring experiment conducted in Greenbelt, Maryland, where the imaginary part of effective refractive index k was inferred from the measurements of direct and diffuse atmospheric transmittances by a UV-multifilter rotating shadow-band radiometer [UV-MFRSR, U.S. Department of Agriculture (USDA) UV-B Monitoring and Research Network]. Colocated ancillary measurements of aerosol effective particle size distribution and refractive index in the visible wavelengths [by CIMEL sun-sky radiometers, National Aeronautics and Space Administration (NASA) Aerosol Robotic Network (AERONET)], column ozone, surface pressure, and albedo constrain the forward radiative transfer model input, so that a unique solution for k is obtained independently in each UV-MFRSR spectral channel. Inferred values of k are systematically larger in the UV than in the visible wavelengths. The inferred k values enable calculation of the single scattering albedo omega, which is compared with AERONET inversions in the visible wavelengths. On cloud-free days with high aerosol loadings [tau(ext)(440) >0.4], omega is systematically lower at 368 nm (=0.94) than at 440 nm (=0.96), however, the mean omega differences (0.02) are within expected uncertainties of omega retrievals (similar to 0.03). The inferred omega is even ;lower at shorter UV wavelengths ()similar to =0.92), which might suggest the presence of selectively UV absorbing aerosols. We also find that a) decreases with decrease in aerosol loading. This could be due to real changes in the average aerosol composition between summer and winter months at the Goddard Space Flight Center (GSFC) site. Combing measurements of tau(ext) and w, the seasonal dependence of the aerosol absorption optical thickness, tau(rbs)=tau(ext)(1 - omega) is derived in the UV with an uncertainty of 0.01 to 0.02, limited by the accuracy of UV-MFRSR measurement and calibration. The tau(abs) has a pronounced seasonal dependence with maximum values similar to 0.1 occurring in summer hazy conditions and <0.02 in the winter and fall seasons, when aerosol loadings are small. The measured tau(abs) is sufficient to explain both the magnitude and seasonal dependence of the bias in satellite estimates of surface UV irradiance previously seen with ground-based UV measurements. (c) 2005 Society of Photo-Optical Instrumentation Engineers.

Radiative transfer calculations of UV irradiance from total ozone mapping spectrometer (TOMS) satellite data are frequently over- estimated compared to ground-based measurements because of the presence of undetected absorbing aerosols in the planetary boundary layer. To reduce these uncertainties, an aerosol UV absorption closure experiment has been conducted at the National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC) site in Greenbelt, Maryland, using 17 months of data from a shadowband radi- ometer (UV-multifilter rotating shadowband radiometer (UV-MFRSR), U.S. Department of Agriculture (USDA) UV-B Monitoring and Research Network) colocated with a group of three sun-sky CIMEL radiometers (rotating reference instruments of the NASA Aerosol Robotic Network (AERONET)). We describe an improved UV-MFRSR on-site calibration method augmented by AERONET-CIMEL measurements of aerosol ex- tinction optical thickness (t a) interpolated or extrapolated to the UV- MFRSR wavelengths and measurement intervals. The estimated t a is used as input to a UV-MFRSR spectral-band model, along with indepen- dent column ozone and surface pressure measurements, to estimate zero air mass voltages V0 in three longer wavelength UV-MFRSR chan- nels (325, 332, 368 nm). Daily mean ^V0&, estimates and standard de- viations are obtained for cloud-free conditions and compared with the on-site UV-MFRSR Langley plot calibration method. By repeating the calibrations on clear days, relatively good stability (62% in ^V0& )i s found in summer, with larger relative changes in fall-winter seasons. The changes include systematic day-to-day ^V0& decline for extended peri- ods along with step jump changes after major precipitation periods (rain or snow) that affected the diffuser transmission. When daily ^V0& values are used to calculate t a for individual 3-min UV-MFRSR measurements on the same days, the results compare well with interpolated AERONET t a measurements (at 368 nm most daily 1s root mean square (rms) differences were within 0.01). When intercalibrated against an AERO- NET sunphotometer, the UV-MFRSR is proven reliable to retrieve t a , and hence can be used to retrieve aerosol column absorption in the UV. The advantage of the shadowband technique is that the calibration ob- tained for direct-sun voltage can then be applied to diffuse-radiance volt- age to obtain total and diffuse atmospheric transmittances. These trans- mittances, in combination with accurate t a data, provide the basis for estimating aerosol column absorption at many locations of the USDA UV-B Monitoring and Research network and for correction of satellite estimations of surface UV irradiance. © 2005 Society of Photo-Optical Instru-

As a part of the Big Bend Regional Aerosol and Visibility Observational Study (BRAVO, July–October 1999), aerosol physical, optical and chemical properties were measured continuously in an effort to characterize visibility in Big Bend National Park. Surface-based estimates of aerosol extinction coefficients derived from size distribution data were compared to aerosol optical properties retrieved independently from ground-based remote sensing measurements from the United States Department of Agriculture (USDA) UVB radiometer network site. Comparisons suggested that for the majority of the study, surface visibility was a good indicator of the column aerosol optical depth, with a correlation coefficient of r2=0.77. The average (and one standard deviation) aerosol optical depth from the USDA network was 0.13±0.06 at a wavelength of 500 nm. Ångstrom wavelength exponents were computed for both data sets to characterize the spectral variations of aerosol optical properties over the wavelength range of 415–860 nm. Variations in Ångstrom exponents corresponded to changing aerosol properties as seen in the ground-based composition and size distribution data sets. The average Ångstrom exponent from in situ measurements was 1.5±0.4 compared to column estimates of 1.3±0.4. The root mean square of the difference between the estimates of Ångstrom exponents was 0.20 (∼12%) and on average the estimates were highly correlated (r2=0.89). Aerosol optical depths and ambient surface aerosol extinction coefficients were positively correlated with PM2.5 sulfate mass concentrations (r2=0.68 and r2=0.79, respectively), suggesting that sulfate aerosols were a major contributor to visibility degradation and column aerosol loading during the study.

We report final results of an aerosol UV absorption closure experiment where a UV-shadow-band radiometer (UV-MFRSR, USDA UVB Monitoring and Research Network) and 4 rotating sun-sky radiometers (CIMEL. NASA AERONET network) were run side-by-side continuously for 17 months at NASA/GSFC site in Greenbelt, MD. The aerosol extinction optical thickness, Text, was measured by the CIMEL direct-sun technique in the visible and at two UV wavelengths 340 and 380 nm. These results were used for UV-MFRSR daily on-site calibration and 3-min measurements of tau(ext) at 325nm, 332nm and 368nm. The tau(ext) measurements were used as input to the radiative transfer model along with AERONET retrievals of the column-integrated particle size distribution (PSD) to infer an effective imaginary part of the UV aerosol refractive index, k, by fitting MFRSR measured voltage ratios. Using all cases for cloud-free days, we derive diurnal and seasonal dependence of the aerosol absorption optical thickness, tau(abs),, with an uncertainty 0.01-0.02. At our site tau(abs) follows pronounced seasonal dependence with maximum values similar to0.07 at 368nm (similar to0.15 at 325nm) occurring in summer hazy conditions and <0.02 in winter-fall seasons, when aerosol loadings are small. Inferred values of k allow calculation of the single scattering albedo, omega, in UVA and comparisons with AERONET almucantar omega(440) retrievals at 440nm. Overall, omega was slightly lower in UV than in the visible: case average =0.93 compared to =0.95. However, the differences (omega(440) - omega(368)> similar to0.02, rms difference similar to0.016) are smaller than uncertainties of both retrievals (deltaomegasimilar to0.03). Low values are consistent with higher values for imaginary refractive index, k: similar to0.01 compare to similar to0.006. However, mean differences in k(similar to0.004) were only slightly larger than AERONET retrieval uncertainty deltak similar to0.003(27). We also found that a) decreases with decrease in zero, suggesting different aerosol composition in summer and winter months. So far, our results do not allow explaining the causes of apparent larger aerosol absorption in UV. Continuing co-located measurements at GFSC is important to improve the comparison statistics, but conducting aerosol absorption measurements at different sites with varying conditions is also desirable.

This is the second continuation of work begun by Dave Bigelow and James Slusser in their study of the same name published in 2000 in J. Geophys. Res., 105, 4833-4840, which studied only a few instruments over a limited in-service time span. Part 1 expanded the Langley stability analysis by using 42 instruments over 5 years of field service. This part 2 expands stability as expressed with repeated laboratory lamp calibrations of the instruments, and compares these to the prior Langley analysis. 115 cases representing 44 instruments covering seven years of deployment are studied. Complicating this analysis are the four versions of the UV-MFRSR instrument that span the analysis time frame, and the results are presented as such. These results show the mean annual drift in sensitivity for the seven nominal wavelengths of the UV-MFRSR instrument are: pre-Rev.M: 300nm -8.8%, 305nm -8.1%, 311nm -7.4%, 317nm -8.3%, 325nm 7.3%, 332nm -7.6%, 368nm -7.2%; Rev.M: 300nm -7.5%, 305nm -7.1%, 311nm -6.5%, 317nm -5.6%, 325nm -5.8%, 332nm -5.3%, 368nm -5.1%; Rev.NP; 300nm -10.1%, 305nm -7.2%, 311nm -8.3%, 317nm -4.3%, 325nm -3.6%, 332nm -3.7%, 368nm -3.5%; and Rev.Q: 300nm -5.6%, 305nm -5.8%, 311nm -3.8%, 317nm -4.4%, 325nm -4.8%, 332nm -4.6%, 368nm -3.5%.

Converting discreet narrowband filter radiometer irradiance measurements into continuous allows the construction of weighted doses such as an erythemal and plant action spectra. Synthetic spectra were retrieved from 7 UV narrowband channels using a fast 5 parameter fit. The synthetic spectra are compared with measurements from a collocated spectroradiometer and the erythemally weighted doses from the synthetic spectra are compared with daily erythemal doses from a collocated broadband radiometer. The agreement in spectral data ranges generally from 0.75 to 1.25 depending upon wavelength and solar zenith angle. Agreement between daily erythemal. doses are generally between 0.70 and 0.90.

Compared to the visible spectral region very little is known about aerosol absorption in UV. Without such information it is impossible to quantify a cause to the observed discrepancy between modeled and measured UV irradiances and photolysis rates. We report preliminary results of an aerosol closure experiment where a UV-shadow-band radiometer (UVMFRSR, USDA UVB Monitoring and Research Network) and well-calibrated sun-sky radiometer (CIMEL, NASA AERONET network) were run side-by-side for several months at NASA/GSFC site in Greenbelt, MD. The aerosol optical thickness, τ, was measured at 340nm and 380nm by the CIMEL direct-sun technique. These results compared well with independent MFRSR τ measurements at 368nm (using total minus diffuse irradiance technique). Such comparisons provide an independent check of both instrument’s radiometric and MFRSR’s angular calibration and allow precise tracking of the UV filter degradation by repeating the comparisons made at somewhat regular time intervals. The τ measurements were used as input to a radiative transfer model along with AERONET retrievals of the column-integrated particle size distribution (PSD) to infer an effective imaginary part of the UV aerosol refractive index (k). This was done by fitting the MFRSR diffuse fraction measurements to the calculated values for each UV spectral channel. Inferred values of refractive index and PSD allow calculation of the single scattering albedo, ω, in the UV and comparisons with AERONET ω retrievals. The advantage of utilizing diffuse fraction measurements is that radiometric calibration is not needed for the MFRSR since the same detector measures both the total and diffuse flux. The additional advantage is that surface albedo is much smaller in the UV than in the visible spectral range and has much less effect on aerosol measurements.

Comparisons of UV irradiances measured by the USDA UVB Monitoring and Research Network at 305- and 368-nm with retrievals from the NASA TOMS and a multiple scattering radiative transfer code were made for an 18-month period from January 1, 2000 through May 31, 2001 for Las Cruces, New Mexico, USA (32.6degreesN, 106.7degreesW, 1317 m. elevation) and Billings, Oklahoma, USA (36.6degrees, 97.5degreesW, 317 m elevation). Agreement is generally within +/- 12% for all sky conditions and 8% for clear skies. The effects of aerosols is mostly < 5%, consistent with the measured aerosol optical depths at 368 nm within the range of 0.05 and 0.25.

A methodology for direct-Sun ozone retrieval using the ultraviolet multifilter rotating shadow-band radiometer (UV-MFRSR) is presented. Total vertical column ozone was retrieved in three stations: Mauna Loa, Hawaii, in the U.S., and Regina, Saskatchewan, and Toronto, Ontario, in Canada, from direct solar irradiances of the UV-MFRSR at 325-, 305-, 332-, and 311-nm channels (2-nm FWHM). The total uncertainty of ozone retrievals in this study is +/-2.0%. For Mauna Loa the mean ratios of the UV-MFRSR column ozone retrievals to the collocated Dobson and Brewer were 0.998 and 0.986 between May and September of 1999. The mean ratio of UV-MFRSR retrievals to the collocated Brewer retrievals was 1.012 in Toronto between April and August of 1999, and the mean ratio of retrievals of the UV-MFRSR to the collocated Brewer was 0.988 in Regina between June and September of 1999. Total vertical column ozone values for solar zenith angles of >70 degrees were not considered, because of the signal-to-noise ratio and the angular response of the instruments, and were not used in the evaluation. The advantages of total vertical column ozone retrieval using UV-MFRSR include relatively low cost, computer-controlled operation, automated calibration stability checks, and minimal maintenance. It allows for the real-time measurement of total vertical column ozone. The UV-MFRSR is being used at 28 sites across the United States and 2 sites in Canada that form the U.S. Department of Agriculture UV-B Radiation Monitoring and Research Program. This constitutes a unique network of total vertical colunm ozone measurement.

Context With the success of zidovudine chemoprophylaxis for prevention of perinatal transmission of the human immunodeficiency virus (HIV), an increasing number of HIV-exposed but uninfected children will have in utero exposure to zidovudine and other antiretroviral drugs.Objective To evaluate the long-term effects of in utero exposure to zidovudine vs placebo among a randomized cohort of uninfected children.Design Prospective cohort study based on data collected during Pediatric AIDS Clinical Trials Group Protocol 076, a perinatal zidovudine HIV prevention trial, and Protocol 219, a long-term observational protocol.Setting Pediatric research clinics in the United States.Patients Two hundred thirty-four uninfected children born to 230 HIV-infected women enrolled in Protocol 076 and followed up through February 28, 1997, in Protocol 219 (122 in the zidovudine group and 112 in the placebo group).Main Outcome Measures Physical growth measurements, immunologic parameters, cognitive/developmental function, occurrence of neoplasms, and mortality data assessed every 6 months for children younger than 24 months and yearly thereafter or as clinically indicated. Baseline echocardiogram and funduscopic evaluations were collected before 36 months of age.Results Median age of children at time of last follow-up visit was 4.2 years (range, 3.2-5.6 years). There were no significant differences between children exposed to zidovudine and those who received placebo in terms of sequential data on lymphocyte subsets; weight, height, and head circumference z scores; and cognitive/ developmental function. No deaths or malignancies occurred. Two children (both exposed to zidovudine) are being followed up for abnormal, unexplained ophthalmic findings. One child exposed to zidovudine had a mild cardiomyopathy on echocardiogram at the age of 48 months; the child is clinically asymptomatic.Conclusions No adverse effects were observed in HIV-uninfected children with in utero and neonatal exposure to zidovudine followed up for as long as 5.6 years. Continued prospective evaluations of children born to HIV-infeded women who are exposed to antiretroviral or immunotherapeutic agents are critical to assess the longterm safety of interventions that prevent perinatal HIV transmission.

CONTEXT With the success of zidovudine chemoprophylaxis for prevention of perinatal transmission of the human immunodeficiency virus (HIV), an increasing number of HIV-exposed but uninfected children will have in utero exposure to zidovudine and other antiretroviral drugs. OBJECTIVE To evaluate the long-term effects of in utero exposure to zidovudine vs placebo among a randomized cohort of uninfected children. DESIGN Prospective cohort study based on data collected during Pediatric AIDS Clinical Trials Group Protocol 076, a perinatal zidovudine HIV prevention trial, and Protocol 219, a long-term observational protocol. SETTING Pediatric research clinics in the United States. PATIENTS Two hundred thirty-four uninfected children born to 230 HIV-infected women enrolled in Protocol 076 and followed up through February 28, 1997, in Protocol 219 (122 in the zidovudine group and 112 in the placebo group). MAIN OUTCOME MEASURES Physical growth measurements, immunologic parameters, cognitive/developmental function, occurrence of neoplasms, and mortality data assessed every 6 months for children younger than 24 months and yearly thereafter or as clinically indicated. Baseline echocardiogram and funduscopic evaluations were collected before 36 months of age. RESULTS Median age of children at time of last follow-up visit was 4.2 years (range, 3.2-5.6 years). There were no significant differences between children exposed to zidovudine and those who received placebo in terms of sequential data on lymphocyte subsets; weight, height, and head circumference z scores; and cognitive/developmental function. No deaths or malignancies occurred. Two children (both exposed to zidovudine) are being followed up for abnormal, unexplained ophthalmic findings. One child exposed to zidovudine had a mild cardiomyopathy on echocardiogram at the age of 48 months; the child is clinically asymptomatic. CONCLUSIONS No adverse effects were observed in HIV-uninfected children with in utero and neonatal exposure to zidovudine followed up for as long as 5.6 years. Continued prospective evaluations of children born to HIV-infected women who are exposed to antiretroviral or immunotherapeutic agents are critical to assess the long-term safety of interventions that prevent perinatal HIV transmission.

Most AIDS cases in children worldwide occur as a result of vertical transmission, but there is no simple, reliable, and inexpensive test to diagnose HIV-1 infection in neonates. We evaluated an IgE assay for diagnosis of HIV-1 in infants. We tested 190 serum samples from 78 children (36 HIV-1 infected, 42 uninfected) born to HIV-1 seropositive mothers. Infection was diagnosed by two positive HIV-1 viral cultures or a positive ELISA and Western blot after 18 months of age. We grouped the children according to their age at initial sample collection: birth to 6 months (group 1), 7–12 months (group 2), 13–24 months (group 3), and 25–60 months (group 4). The total (average) number of samples tested per child in each group was: 75 (2·6), 48 (3), 29 (2–9), and 38 (1–7) for groups 1, 2, 3, and 4, respectively. Sequential samples taken at different ages were tested in 41 children. We treated serum or plasma samples (200 μL) with the protein G affinity method twice (rProtein G affinity method, Isolab Inc, Akron, OH, USA). The HIV enzyme immunoassay kit (Coulter Immunology, Hialeah, FL, USA) plates were incubated at room temperature with pretreated serum for 30 min, aspirated and washed five times, after which time horseradish peroxidase-conjugated with antihuman IgE was added (Incstar Corp, Stillwater, MN, USA), and the mixture incubated at room temperature. Plates were reaspirated and rewashed five times. Fresh substrate solution (100 μL) was added to each well and incubated at room temperature and the reaction stopped by adding H2SO4. The plate was read with bichromathic absorbance at 492 nm with 620 nm as reference. Controls were a blank with conjugate and substrate, serum from one HIV-1 seronegative person and one HIV-1 seropositive person. A cutoff for positive and negative values was based on previously-tested adults (116 HIV seropositive, 54 HIV seronegative; unpublished data). Specific IgE sensitivity, specificity, and predictive value with 95% CI were calculated with the first sample from each infant. HIV-IgE enzyme immunoassay correctly diagnosed HIV status in 187 (98%) of the 190 serum samples tested; 35 of 36 HIV-1 infected children were identified as HIV-IgE seropositive; 41 of 42 seronegative children were correctly identified as HIV-IgE seronegative (table). The false-negative result was with samples collected during the first 35 months of life in a child who tested positive at 37 months with the IgE test. The false positive test occurred with a single sample from a 1 month-old child. We tested 26 samples in infants younger than 3 months; all samples but one were correctly assigned. Overall, sensitivity was 0·9722 and specificity 0·9762 with a positive predictive value of 0·9722 and negative predictive value of 0·9762. Individual group analyses (table) showed sensitivity, specificity, and predictive values of 93% in group 1 and 100% in groups 2, 3, and 4. In children who provided sequential samples results were consistent over time, with the exception of the false negative.TableDetection of HIV-1 specific IgE antibodyGroup (age in months)Group 1 (0–6)*Group 1 included 24 children <3 months of age when first tested; 12 children were 0–1 month and 12 children were 2–3 months of age;Group 2 (7–12)Group 3 (13–24)Group 4 (25–60)HIV (+)†On the basis of viral cultures or HIV ELISA and Western blot. (total n=36)143316HIV (−)†On the basis of viral cultures or HIV ELISA and Western blot. (total n=42)151377Correct HIV+ (IgE test; n=35)133316Correct HIV− (IgE test; n=41)141377Specificity (95% CI)0·93 (0·66–0·99)1·00 (0·75–1·00)1·00 (0·75–1·00)1·00 (0·75–1·00)Sensitivity (95% CI)0·93 (0·66–0·99)1·00 (0·75–1·00)1·00 (0·75–1·00)1·00 (0·75–1·00)Positive predictive value (95% CI)0·93 (0·66–0·99)1·00 (0·29–1·00)1·00 (0·29–1·00)1·00 (0·79–1·00)Negative predictive value (95% CI)0·93 (0·68–0·99)1·00 (0·75–1·00)1·00 (0·59–1·00)1·00 (0·59–1·00)* Group 1 included 24 children <3 months of age when first tested; 12 children were 0–1 month and 12 children were 2–3 months of age;† On the basis of viral cultures or HIV ELISA and Western blot. Open table in a new tab This small study shows that IgE-specific antibodies to HIV-1 may be used for diagnosis: the IgE assay is sensitive and specific in children of various ages, including neonates, and may be more sensitive than IgA assays.1Weiblen BJ Lee FK Cooper ER et al.Early diagnosis of HIV infection in infants by detection of IgA HIV antibodies.Lancet. 1990; 335: 988-990Summary PubMed Scopus (98) Google Scholar, 2Livingston A Hutton N Halsey N Kline R Joyner M Quinn T Human immunodeficiency virus-specific IgA in infants born to human immunodeficiency virus infected women.Arch Pediatr Adolesc Med. 1995; 149: 503-507Crossref PubMed Scopus (10) Google Scholar, 3Landesman S Weinblein B Mendez H et al.Clinical utility of HIV-IgA immunoblot assay in the early diagnosis of perinatal HIV infection.JAMA. 1991; 266: 3443-3446Crossref PubMed Scopus (60) Google Scholar, 4Quinn TC Kline RI Halsey N et al.Early diagnosis of perinatal HIV infection by detection of viral specific IgA antibodies.JAMA. 1991; 266: 3439-3442Crossref PubMed Scopus (70) Google Scholar IgE is produced early in the fetus,5Bierman C Pearlman D Allergic diseases from infancy and adulthood. WB Saunders, Philadelphia1988: 1-19Google Scholar leading to high IgE concentrations in those infants infected in utero. Since IgE does not cross the placenta barrier, detection of IgE specific for HIV-1 at delivery suggests fetal IgE synthesis. IgE may also be produced earlier than IgA in response to infection in infants infected at delivery. Assays that are sensitive and specific to detect HIV-1 infection in infants are generally unavailable but are important in developing countries where PCR and viral culture may not be available, and may be economically advantageous in industrialised countries. This study was supported by NIMH 1-P50-MH42555, Fogarty International Training Grant D43-TW00017-5, and NIAID grants AI2352 and AI27560.