Incidence of healthcare-associated infections in patients with fever during the first 48 hours after decannulation from veno-venous extracorporeal membrane oxygenation.

INTRODUCTION: Fevers following decannulation from veno-venous extracorporeal membrane oxygenation often trigger an infectious workup; however, the yield of this workup is unknown. We investigated the incidence of post-veno-venous extracorporeal membrane oxygenation decannulation fever as well as the incidence and nature of healthcare-associated infections in this population within 48 hours of decannulation. METHODS: All patients treated with veno-venous extracorporeal membrane oxygenation for acute respiratory failure who survived to decannulation between August 2014 and November 2018 were retrospectively reviewed. Trauma patients and bridge to lung transplant patients were excluded. The highest temperature and maximum white blood cell count in the 24 hours preceding and the 48 hours following decannulation were obtained. All culture data obtained in the 48 hours following decannulation were reviewed. Healthcare-associated infections included blood stream infections, ventilator-associated pneumonia, and urinary tract infections. RESULTS: A total of 143 patients survived to decannulation from veno-venous extracorporeal membrane oxygenation and were included in the study. In total, 73 patients (51%) were febrile in the 48 hours following decannulation. Among this cohort, seven healthcare-associated infections were found, including five urinary tract infections, one blood stream infection, and one ventilator-associated pneumonia. In the afebrile cohort (70 patients), four healthcare-associated infections were found, including one catheter-associated urinary tract infection, two blood stream infections, and one ventilator-associated pneumonia. In all decannulated patients, the majority of healthcare-associated infections were urinary tract infections (55%). No central line-associated blood stream infections were identified in either cohort. When comparing febrile to non-febrile cohorts, there was a significant difference between pre- and post-decannulation highest temperature (p < 0.001) but not maximum white blood cell count (p = 0.66 and p = 0.714) between the two groups. Among all positive culture data, the most commonly isolated organism was Klebsiella pneumoniae (41.7%) followed by Escherichia coli (33%). Median hospital length of stay and time on extracorporeal membrane oxygenation were shorter in the afebrile group compared to the febrile group; however, this did not reach a statistical difference. CONCLUSION: Fever is common in the 48 hours following decannulation from veno-venous extracorporeal membrane oxygenation. Differentiating infection from non-infectious fever in the post-decannulation veno-venous extracorporeal membrane oxygenation population remains challenging. In our febrile post-decannulation cohort, the incidence of healthcare-associated infections was low. The majority were diagnosed with a urinary tract infection. We believe obtaining cultures in febrile patients in the immediate decannulation period from veno-venous extracorporeal membrane oxygenation has utility, and even in the absence of other clinical suspicion, should be considered. However, based on our data, a urinalysis and urine culture may be sufficient as an initial work up to identify the source of infection.

Ovarian reserve and PGD treatment outcome in women with myotonic dystrophy.

Myotonic dystrophy (DM) is the most common form of muscular dystrophy in adults. There are conflicting reports about its effect on female fertility. This study investigated ovarian reserve and IVF-preimplantation genetic diagnosis (PGD) outcome in women with DM1. A total of 21 women undergoing PGD for DM1 were compared with 21 age- and body mass index-matched women undergoing PGD for other diseases. Ovarian reserve markers, response to stimulation, embryo quality and clinical pregnancy and live birth rates were compared. Day-3 FSH concentration was higher, while anti-Müllerian hormone concentration and antral follicle count were lower in the DM1 group (median, range: 6.9 (1.8-11.3) versus 5.7 (1.5-10.7)IU/l; 0.9 (0.17-5.96) versus 2.68 (0.5-9.1)ng/ml; and 13 (0-63) versus 23 (8-40) follicles, respectively, all P < 0.05). Total FSH dose was higher (5200 versus 2250 IU, P = 0.004), while the numbers of oocytes retrieved (10 versus 16, P < 0.04) and metaphase-II oocytes (9 versus 12, P < 0.03) were lower in the DM1 group. The number of cycles with top-quality embryos and the clinical pregnancy rate were lower in the DM1 group. In conclusion, there is evidence of diminished ovarian reserve and less favourable IVF-PGD outcome in women with DM1. Myotonic Dystrophy (DM) is the most common form of muscular dystrophy in adults. There is evidence of subfertility in males affected with the disease but conflicting reports about the effect of the disease on female fertility. The aim of our study was to investigate ovarian reserve and IVF-PGD results in women with DM. Twenty-one women undergoing preimplantation genetic diagnosis (PGD) treatment for DM were compared to 21 age- and BMI matched women undergoing PGD treatment for other diseases. The two groups were compared for antral follicle count (AFC) and serum anti-Mullerian hormone (AMH) levels (the best known markers of ovarian reserve and fertility potential), ovarian response, embryo quality and pregnancy and live birth rates. AFC and the AMH levels were statistically significant lower in the DM group. Total medication dose needed for ovarian stimulation was higher, the number of oocytes and mature oocytes retrieved, and the number of cycles with top quality embryos were lower in the DM group compared to the controls. In conclusion, there is evidence of diminished ovarian reserve, and less favorable IVF-PGD outcome in women with DM. Therefore, we recommend advising these women about the possibility of early decreasing ovarian function in order to prevent any delay in reproductive planning.

Absent gallbladder on fetal ultrasound: prenatal findings and postnatal outcome.

OBJECTIVES: Fetal gallbladder non-visualization on prenatal ultrasound in the second trimester is uncommon and in most cases the gallbladder is detected eventually. Associations of gallbladder non-visualization with cystic fibrosis, aneuploidy, agenesis of the gallbladder and biliary atresia have been reported. We present our experience and review the literature. METHODS: During the study period from January 2004 to June 2009 we collected prospectively cases of non-visualization of the fetal gallbladder in the second trimester. In each case the fetus was evaluated by two examiners on at least two occasions, at least a week apart. Cases with no additional sonographic malformations were designated as isolated. Further evaluation included follow-up scans and a meticulous search for fetal anomalies. All patients were offered genetic consultation. Cystic fibrosis testing, amniocentesis for karyotyping and analysis of fetal digestive enzymes in the amniotic fluid were offered. RESULTS: We collected 21 cases of non-visualization of the fetal gallbladder, 16 of which were isolated and five of which had additional malformations. In four of these five, the associated anomalies were severe and the pregnancies were terminated for aneuploidy (two cases of trisomy 18 and one triploidy) or for the severity of the associated anomalies. Associated anomalies included left isomerism with complex cardiac anomaly and intrauterine growth restriction with multisystem anomalies. The fifth fetus had interrupted inferior vena cava with azygos continuation without other anomalies and the child was alive and well at the age of 4 years. In 15 of the 16 isolated cases, antenatal and postnatal development were normal at the last follow-up, ranging from 4 months to 2.5 years. One case of cystic fibrosis was diagnosed prenatally and this pregnancy was terminated. There were no diagnoses of abnormal karyotype or biliary atresia among cases of isolated non-visualization of the gallbladder. CONCLUSIONS: When prenatal non-visualization of the fetal gallbladder is associated with other severe malformation, aneuploidy should be suspected. When it is isolated, if cystic fibrosis is ruled out, the outcome is good.

Evidence for a regulatory idiotypic network in the in vivo response to H-2 antigens.

Treatment of BALB/c mice with purified pig antiidiotype to 11-4.1 (anti-H-2Kk) monoclonal antibody has been found previously to induce the appearance of idiotype-bearing molecules (Id') in the serum of these mice, in the absence of detectable antigen-binding activity. In the present study we examined the effect of subsequent immunization of such antiidiotype-primed mice with the original H-2Kk antigen. Skin grafting of virgin BALB/c mice with BALB.K skin did not generate any detectable Id' antibodies when tested by enzyme-linked immunosorbent assay (ELISA). In contrast, grafting of antiidiotype-primed mice with BALB.K skin specifically boosted ther serum level of Id' molecules. Challenge of antiidiotype-primed mice with either B10.D2 or rat skin had no effect on the production of such Id' molecules. Absorption studies demonstrated that the majority of Id' molecules induced by H-2Kk antigenic stimulus and detected in ELISA are antigen-nonbinding molecules, thus indicating specific restimulation by the original H-2Kk antigen of nonbinding idiotype-positive B cell clones. The relevance of these findings to the existence of network interactions in the immune response to H-2 antigens is discussed.

Hemoglobin interaction: modification of solid phase composition in the sickling phenomenon.

Direct analyses of solid phase formed by deoxygenating solutions of sickle-cell hemoglobin (Hb S) in the presence of certain other hemoglobin species show that hemoglobins A and C can participate in the filamentous fine structure characteristic of the sickling phenomenon. In contrast, fetal hemoglobin (Hb F) is nearly completely excluded.

Congenital diaphragmatic hernia: review of the literature in reflection of unresolved dilemmas.

BACKGROUND: Congenital diaphragmatic hernia (CDH) is a rare but clinically and scientifically challenging condition. The introduction of ultrasound has enabled early prenatal detection and consequently, hope of early therapeutic intervention. AIM: We undertook the task to review the recent developments in understanding the pathology of CDH as well as the history and current management strategies to aid perinatologists in consultations with parents of CDH-affected foetuses. STUDY DESIGN: A Medline search was undertaken of all reports and reviews published between 1980 and 2008 using MeSH search terms 'diaphragmatic hernia', 'congenital' and 'newborn'. RESULTS: The true incidence of CDH is still difficult to estimate because of the high incidence of hidden mortality of CDH. Complete case ascertainment also poses difficulties in assessment of the impact of new therapeutic modalities on overall survival. Recent improvements in prenatal detection are a milestone in affording time for re-assessments and parental counselling. The true benefit of antenatal therapy is circumscribed and should be offered only in selected cases of isolated severe CDH as defined by existing guidelines. Postnatal intensive respiratory supportive therapy and innovative surgical techniques within specialized tertiary centres has had a major impact on survival of babies with CDH. CONCLUSION: The high survival of 'selected cases' that are live births and benefit from optimal care will be difficult to improve by antenatal interventions. The multidisciplinary approach to basic research and randomized clinical trials will further define the best approach to the foetus and neonate with CDH.

Effects of a copper-medicated intrauterine device on ovarian artery, uterine artery, and intrauterine blood flow.

AIM: To determine the effect of a copper-medicated intrauterine device (IUD) on ovarian, uterine, arcuate, radial and subendometrial Doppler-derived indices of blood flow. METHOD: 23 regularly menstruating patients requested insertion of an IUD. All patients had a copper T (Nova T) IUD inserted between days 8 and 11 of the menstrual cycle. Ovarian, uterine, arcuate, radial and subendometrial artery pulsatility indices (PIs) were assessed by transvaginal color Doppler prior to insertion between days 8 and 11 of the menstrual cycle, and after 2 months in the same period of the cycle. Ovarian, uterine, arcuate, radial and subendometrial artery PIs were considered prior to and following IUD insertion. RESULTS: No differences were recorded in any of the blood vessels sampled between pre- and post-insertion PIs. CONCLUSION: No significant change in ovarian or in uterine system vascular impedance is associated with the presence of a copper-medicated IUD.

Prenatal diagnosis of biliary atresia: A case series.

BACKGROUND: Biliary atresia is a progressive disease presenting with jaundice, and is the most common indication for liver transplantation in the pediatric population. Prenatal series have yielded conflicting results concerning a possible association between BA and prenatal nonvisualization of the gallbladder. AIMS: This retrospective case series was performed to assess the association between biliary atresia, prenatal nonvisualization of the gallbladder and other sonographic signs. STUDY DESIGN/SUBJECTS: We identified biliary atresia patients who underwent a Kasai procedure by a single pediatric surgeon and/or follow up by a single pediatric gastroenterologist. Axial plane images and/or video recordings were scrutinized for sonographic signs of biliary atresia on the second trimester anomaly scan. OUTCOME MEASURES: Proportion of biliary atresia cases with prenatal sonographic signs. RESULTS: Twenty five charts of children with biliary and high quality prenatal images were retrieved. 6/25 (24%) of cases analyzed had prenatal nonvisualization of the gallbladder or a small gallbladder on the prenatal scan. Two cases had biliary atresia splenic malformation syndrome. None of the cases had additional sonographic markers of biliary atresia. CONCLUSIONS: Our study suggests that in addition to the well-established embryonic and cystic forms, an additional type can be suspected prenatally, which is characterized by prenatal nonvisualization of the gallbladder in the second trimester. This provides additional evidence that some cases of BA are of fetal rather than perinatal onset and may have important implications for prenatal diagnosis, for counseling and for research of the disease's etiology and pathophysiology.

'Page kidney'. Hypertension caused by chronic subcapsular hematoma.

Conditions analogous to an experimental model of hypertension described by Page in 1939 are called "Page kidney." In chronic subcapsular hematoma, the most common clinical counterpart to Page's model of renal parenchymal compression, a review of the literature reveals that hypertension is usually cured by nephrectomy, but is seldom cured by mere evacuation of the hematoma. To our knowledge, no patient remaining hypertensive after evacuation has undergone nephrectomy. In the patient described herein, a liquified subcapsular hematoma reaccumulated after it was drained percutaneously, and therefore it had to be evacuated surgically. Persistent renin-mediated hypertension, however, prompted curative nephrectomy. The response to more prolonged percutaneous drainage might have guided more effective initial surgery.

Effects of anatomic site, oral stimulation, and body position on estimates of body temperature.

BACKGROUND: A prior investigation characterized the range of body temperature in healthy young adults and established the importance of diurnal variations in defining the febrile state. METHODS: Sequential rectal, oral, and tympanic membrane temperature measurements were performed on 22 healthy subjects to determine the quantitative effects of anatomic site, oral stimulation, and body position on estimates of body temperature. RESULTS: Mean rectal temperatures exceeded concurrent oral readings by 0.4 degrees C +/- 0.4 degrees C (0.8 degrees F +/- 0.7 degrees F), which, in turn, exceeded concurrent tympanic membrane readings (obtained with a digital thermometer [IVAC Corp, San Diego, Calif]) by 0.4 degrees C +/- 1.1 degrees C (0.7 degrees F +/- 2.0 degrees F). Tympanic membrane readings were significantly more variable (both intrasubject and intersubject) than rectal or oral readings, especially when cerumen was present in the external ear canal being examined (P<.05). Mastication and smoking both caused significant increases in oral temperature that persisted for greater than 20 minutes. Drinking ice water caused a significant but more transient decrease in oral temperature. Of these activities, only mastication appeared to influence tympanic membrane readings. Body position exerted a modest effect on rectal temperature readings, but did not significantly affect oral or tympanic membrane readings. CONCLUSIONS: These findings indicate that, in addition to diurnal fluctuations in body temperature, the effects of anatomic site, oral stimulation, and body position should be considered in establishing criteria for the febrile state.

Enhanced lymphoid cell recovery after bone marrow transplantation: correlation with the presence of costimulatory antibodies in serum.

We describe a patient with T cell deficiency who underwent bone marrow transplantation (BMT) from an HLA-identical brother. The patient's white blood cell count recovered with exceptional rapidity post-BMT: after 7 to 9 days it rose sharply to 98x10(9) cells/L, 76% of which were mononuclear leukocytes. It then decreased, and a second peak was observed 250 days post-BMT. Lymphocytes from both peaks displayed a phenotype of mature T cells together with characteristics of a constitutively activated state; that is, they 1) exhibited high levels of tyrosine-phosphorylated T cell receptor (TCR) zeta chain, 2) spontaneously secreted IL-2, 3) expressed activation specific cell surface markers, and 4) were unresponsive to in vitro stimuli. The increased cell counts in both peaks correlated with the presence of anti-lymphocytic antibodies in the patient's serum, which reacted with peripheral blood lymphocytes (PBLs) both from the donor and from unrelated individuals. These antibodies were present before BMT and reappeared post-BMT. Variable number tandem repeats analysis revealed that the patient's PBLs were chimeras for up to 2 years post-BMT. This finding could explain the newly synthesized post-BMT anti-lymphocytic antibodies and the appearance of the second WBC peak during that period. The patient's anti-lymphocytic antibodies displayed costimulatory activity, enhancing the in vitro proliferation of normal T cells suboptimally activated via the TCR. The unique characteristics of these antibodies could explain the enhanced T cell recovery observed post-BMT as well as the constitutive activation state of these cells. Furthermore, such antibodies may eventually facilitate development of a therapeutic method for inducing enhanced post-BMT recovery.

Early second trimester transvaginal ultrasound anomaly scan does not cause adverse perinatal outcome.

OBJECTIVE: During an early second-trimester transvaginal ultrasound anomaly scan, pressure is applied to the uterus, and the fetus is often rotated manually to allow scanning of its various organs. This study was designed to determine if performing a transvaginal ultrasound anomaly scan during the early second trimester of pregnancy is associated with adverse perinatal outcome or cord entanglement. METHODS: During the 4.5year study period we prospectively collected cases of routine ultrasound scans at 14-17weeks gestation performed as anomaly screening, together with perinatal outcome. The study population consisted of 164 women who underwent a transvaginal approach, and the control population consisted of 224 women in which a transabdominal approach was used. Data on perinatal parameters was collected from delivery charts from the four local hospitals. RESULTS: There were more operative deliveries (vaginal or Cesarean) in the transvaginal scan group (32% vs. 23%, p=0.05). However, on multiple logistic regression analysis vaginal scans were not associated with increased operative delivery rates with an adjusted odds ratio of 1.47 and a 95% confidence interval of 0.85-2.54. There were no other clinically significant differences in perinatal outcomes, or in cord entanglement. CONCLUSIONS: Transvaginal ultrasound anomaly scan conducted in the early second trimester of pregnancy is a safe procedure for the fetus.

An 11,000-isolate same plate/same day comparison of the 3 most widely used platforms for analyzing multidrug-resistant clinical pathogens.

Stewardship of the dwindling number of effective antibiotics relies on accurate phenotyping. We sought to conduct the first large-scale, same plate and day comparison of the 3 most widely used bacterial analyzers. A total of 11,020 multidrug-resistant clinical isolates corresponding to more than 485,000 data points were used to compare the 3 major identification and antibiotic susceptibility testing (AST) platforms. Bacterial suspensions, prepared from a single plate, were simultaneously tested on all platforms in the same laboratory. Discrepancies were derived from MIC values using 2014 interpretive guidelines. Molecular methods and manual microbroth dilution were reference standards. Most discrepancies were due to drug-organism-AST platform combination instead of individual factors. MicroScan misidentified Acinetobacter baumannii (P<0.001) and underestimated carbapenem susceptibility in Klebsiella pneumoniae. Vitek-2 and Phoenix had higher discrepancies for blaKPC-containing Enterobacteriaceae (P<0.05) and reported false susceptibilities more often. While all platforms performed according to standards, each had strengths and weaknesses for organism identification, assaying specific drug-organism combinations and inferring carbapenemase production.

Changes in lymphocyte subsets in myasthenia gravis: correlation with level of antibodies to acetylcholine receptor and age of patient.

We report a detailed analysis of the subsets of lymphocytes in patients with myasthenia gravis (MG). There was a slight, nonsignificant increase in the level of CD5+ B lymphocytes among MG patients as compared with normal controls. The proportion of CD5+ T cells in MG was similar to that in controls. However, whereas age had no effect on the level of these cells in normal individuals, a significant age-related decrease of these cells was present in MG patients. The proportion of double-positive CD4+CD8+ T cells was significantly increased in MG. The level of the CD29+CD4+ (helper-inducer) subset was significantly higher in MG patients than in controls. There was no correlation between the titer of autoantibodies to acetylcholine receptor and the level of either CD29+CD4+ T cells or CD5+ B cells among MG patients. The only T-cell subset that correlated with the autoantibody titer was the CD45RA+CD4+ (suppressor-inducer) subset of CD4+ T cells.

Mechanisms involved in the weak alloimmunogenicity of Thy-1 on mouse brain.

Immunization of mice with allogeneic brain homogenates fails to elicit an appreciable response to the Thy-1 antigen. The aim of the present study was to determine the mechanism of the low immunogenicity of allogeneic brain. Immunization of C3H mice with freshly prepared mixtures of AKR/J thymus cells with either AKR/J or C3H brain homogenates elicited a primary response to the Thy-1.1 antigen as effectively as immunization with AKR/J thymus cells. When the mixtures were incubated overnight prior to injection, only AKR/J brain homogenate but not C3H brain homogenate abrogated the capacity of AKR/J thymus cells to elicit an anti-Thy-1.1 response. Suppressor T cells did not seem to be responsible for the inability of brain to elicit an anti-Thy-1 response, as mice that received cyclophosphamide 2 days prior to injection of brain did not produce Thy-1 antibodies. Antigenic competition also did not seem to be the cause for the weak immunogenicity of Thy-1 on brain, as mixtures of thymus and brain were capable of eliciting a primary response. When spleen cells from mice hyperimmunized against Thy-1 were transferred to normal syngeneic mice, subsequent immunization with brain homogenate was capable of eliciting Thy-1 antibodies. These results indicate that Thy-1 on brain may resemble a hapten, in being incapable of eliciting a primary immune response, but behaves like a complete antigen in boosting a secondary response.

The expression of CD8 on B lymphocytes in HIV-infected individuals.

In HIV-1 infected individuals the CD8 + T lymphocyte population is markedly activated as reflected by increased expression of the CD38 and CD45RO activation markers and elevated serum levels of soluble CD8 antigen. We have previously shown that in vitro activation of peripheral blood lymphocytes results in the appearance of T cell markers on B cells. In the present study B lymphocytes from HIV-1-infected individuals were tested for the expression of the CD8 T cell antigen, using F(ab')2 fragments of antibodies against the CD8 and CD19 antigens. The proportion of CD19 + B cells which co-expressed CD8 was significantly elevated among 55 HIV-infected individuals (7.20 +/- 1.24%, mean +/- S.E.) as compared with among 22 normal controls (3.32 +/- 0.70%). The proportion of CD4 + cells decreased significantly in HIV-infected individuals in accordance with the progression of the infection, but no significant change in the level of CD8 + CD19 + B cells was seen in different stages of the disease. In contrast, the proportion of CD8 + B cells showed a significant correlation with the proportion of CD8 + cells.

Modulation of the expression of CD4 on HL-60 cells by exposure to 1,25-dihydroxyvitamin D3.

The CD4 molecule functions as a receptor for the binding and infectivity of the human immunodeficiency virus (HIV). It is of interest, therefore, to develop procedures for its down-regulation. In the present study, the effect of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) on the expression of cell surface antigens of the HL-60 promyelocytic leukemia cell line was analyzed. Exposure of HL-60 cells to 1,25(OH)2D3 resulted in down-regulation of CD4 as assessed by their staining with the Leu-3a monoclonal antibody (MoAb). This treatment increased the staining of HL-60 cells with the monocyte-specific 63D3 MoAb. In contrast to the rapid elimination of cell surface CD4 by exposure of HL-60 to phorbol myristate acetate (PMA), the maximal reduction of CD4 by 1,25(OH)2D3 was attained within 48 h after the beginning of the exposure.

The appearance of the CD4+CD8+ phenotype on activated T cells: possible role of antigen transfer.

Stimulation of peripheral blood lymphocytes (PBL) with phytohemagglutinin (PHA) strikingly increased the proportion of CD4+CD8+ cells. Highly purified CD4+ and CD8+ lymphocyte populations cultured in the presence of PHA consistently failed to coexpress the CD8 and CD4 markers. Similarly, exposure of highly purified CD4+ cells to PHA and recombinant interleukin-2 resulted in augmented expression of CD25 but failed to induce the expression of CD8. When purified preparations of either CD4+ or CD8+ cells were activated separately for 3 days and incubated together for an additional 5 h, a considerable proportion of CD4+CD8+ cells was found in the mixture. Cycloheximide treatment did not prevent the appearance of the CD8 marker on CD4 cells. CD4+CD8+ cells isolated from PBL exposed for 3 days to PHA lost their CD8 antigenicity within 24-48 h in the absence of PHA. Increased levels of soluble CD4 and CD8 antigens were found in supernatant fluids of PHA-stimulated cells. T cells failed, however, to bind soluble markers even after prolonged incubation in the presence of supernatant fluids. Our studies show that activation of CD4+ cells per se does not elicit the CD4+CD8+ phenotype and that soluble T cell markers do not bind to T cells. Rather, it seems that direct cell-cell contact is required for the transfer of CD8 molecules from CD8+ cells to the membrane of CD4+ cells.

Activated human T-cells bestow T-cell antigens to non-T-cells by intercellular antigen transfer.

The mechanism of the appearance of T-cell antigens on B-cells, following in vitro activation of peripheral blood lymphocytes, was analyzed using the following model: Purified T-cell suspensions were activated by exposure to phytohemagglutinin (PHA) for 3 days, and then incubated for one hour in the presence of cells of either Raji or K562 cells. The expression of T-cell antigens on the cell lines was determined using immunofluorescent F(ab)2 fragments of monoclonal antibodies (mAbs). Following exposure of the CD19+ Raji cells to activated T lymphocytes, 87.6% of the CD19+ cells coexpressed CD2. A large proportion of the CD19+ cells also expressed CD4, CD5, and CD8 antigens. Similar results were obtained with Raji cells that were prelabeled with calcein AM. In Raji cells, which were rendered CD5+ following incubation with activated T cells, only a negligible level of CD5 mRNA was detected with a sensitive RT-PCR technique, probably attributable to contamination with T cells. K562 cells incubated with activated T cells acquired CD2 but not the CD4 and CD8 antigens. Exposure of either Raji or K562 cells to mAb against CD58 inhibited the transfer of CD2. The present study indicates that following their activation, T-cells gain the capacity to transfer T-cell antigens to non-T cells and that CD2 and CD58 molecules are involved in this process.