Induction of the anti-ergotypic response

The injection of syngeneic activated T cells into rodents caninduce a T cell response against activation markers of the Tcells, ergotopes. The responding antl-ergotypic T cells havebeen shown to suppress experimental autoimmune encephalomyelitis(EAE). This paper reports the characteristics of the antl-ergotypicresponse. It was found that irradiated activated T cells wereas good as untreated living activated T cells in inducing anti-ergotypiccells in vivo. Glutardialdehyde-fixed (0.3%) cells were poorstimulators in vivo and non-stimulatory in vitro. Dilution ofglutardialdehyde to 0.003% before fixation preserved the stimulatorycapacity in vitro. Fixation or irradiation of T cells at differenttimes after activation showed that the stimulatory ergotopeappears only after more than 12 h of activation. This ergotopeis not secreted by activated T cells, but is a structural componentof the activated T cell. Injection of solubilized proteins fromactivated T cells, but not of supernatants from activated Tcells, was able to induce an anti-ergotypic response in vivo.In vitro supernatants from activated T cells also were not stimulatoryto anti-ergotypic T cells. The anti-ergotypic response couldbe measured in draining lymph nodes 3 days after injection,reached a maximum after 7–10 days and subsided thereafter.It was earlier and stronger than the anti-ldiotypic response.Induction of the response was dose dependent. As few as 100cells were able to induce a marked anti-ergotypic response.The ease of the induction and the strength of the anti-ergotypicresponse suggest a physiological role in immunoregulatlon.     

Prevalence of antibody to current influenza virus strains in adolescents

During the Spring of 1986, 118 pupils aged 15-18 years were surveyed for the presence of humoral antibodies to five influenza strains. Prevalence of humoral immunity (HI) antibodies and immunity was found to be related to the year of the strain's emergence and to length of circulation time in the community. A high percentage of the adolescents were not immune to one or more of the tested strains. More than 40% of the studied group were not immune to the old A strains A/Philipines 2/82 (H3N2) and A/Chile 1/83 (H1N1), nearly 70% were not immune to the two B strains (B/USSR 100/83 and B/Ann Arbor 1/86), and almost the entire group (96%) was unprotected against the recent strain A/Singapore 6/86. Only one pupil was immune to all five strains; 35.6%, 22.2%, 17.8%, and 9.2% were immune to one, two, three, or four of the strains, respectively; and 14.4% were not immune to even one strain.     

Vaccination of the Leishmania major susceptible BALB/c mouse. I. The precise selection of peptide determinant influences CD4+ T cell subset expression

BALB/c mice are susceptible to cutaneous lelshmanlasls uponinfection with Leishmania major while C57BL/6 are not. Thereis a major promastigote surface protease (PSP or gp63) whichis available in both native and recomblnant forms, and for whichthe primary amlno acid sequence is known. Immunization withPSP has been shown to offer some protection against challengewith the live organism. Therefore, we attempted to develop apeptide vaccine with PSP peptldes. In the first experiments,recall prollferatlve responses to PSP were measured using aset of 15mer peptldes spanning the entire PSP molecule whichallowed designation of major determinant regions in BALB/c,C57BL/6, and CBA mice. Several of these determinants were promiscuousand shared almost the identical core amlno acid residues inthe different strains. Immunization with major determinant peptldeswas recalled vigorously with L. major soluble antigen as wellas with PSP. The response to peptide was almost entirely T_h1as measured by a localized ELISA assay for single-cell productionof IFN-. A similar assay for IL-5, which overcomes problemsof sensitivity and inhibition by lymphoklnes produced by T_h1cells, Indicates very little production of T_h1 cells even byBALB/c. It was found that if a major responsive peak was examinedby recall with overlapping peptldes, the highest, central peptidegave a mainly Th1 response while the boundary, less efficientpeptldes gave more of a T_h2 response. Possible reasons for thiswere discussed. These results point to the importance of selectingthe exactly appropriate peptide in considering a vacclnogenthat might protect susceptible individuals. Even the choiceof a somewhat immunogenlc peptide within the determinant envelopemight actually exacerbate infection by steering the responsein a T_h2 direction.     

Immune response of adults to sequential influenza vaccination

Annual immunization against influenza is recommended for numerous individuals, but the antibody response to sequential vaccination has not been well characterized. Levels of hemagglutination-inhibition antibody were measured in adults given either two or three doses of trivalent influenza vaccine at six-month intervals. A significant rise in the number of individuals with antibody titers of greater than or equal to 40 was seen for all three antigens only after initial vaccination. Repeated vaccination was necessary to maintain adequate antibody levels only to the A/Brazil (H1N1) antigen; it did not significantly affect the proportions of individuals with protective levels of antibody to either the A/Bangkok (H3N2) or the B/Singapore 222/79 antigens. These findings do not support the current recommendation for annual immunization when the vaccine formulation has not changed.     

The utility of ancillary studies in pediatric FNA cytology.

We evaluated the diagnostic contribution of adjunct studies performed on aspirated material in the work-up of pediatric fine-needle aspiration (FNA) biopsies. Ancillary studies were performed on 54 of 136 (39.7%) pediatric FNA biopsies during a 5-year period. In 23 (16.9%) cases, immunocytochemical (ICC) studies, consisting of immunoperoxidase staining of direct smears and/or cell blocks or flow cytometric immunophenotyping, were performed. The studies were adequate in 14 cases (60.9%), suboptimal in five cases (21.7%), and inadequate in four cases (17.4%). Of the adequate and suboptimal cases, the ICC data helped to narrow the differential diagnosis or classify the disease process in eight cases (42.1%), confirmed cytologic impression in nine cases (47.4%), and gave contradictory results in two cases (10.5%). Adequate material for electron microscopy (EM) was obtained in 14/19 cases (73.7%). Ultrastructural studies were diagnostic, or helped classify the disease process in five cases (35.7%), confirmed the cytologic impression in four cases (28.6%), helped exclude diagnostic considerations in three cases (21.4%), and were judged to be non-contributory in two cases (14.3%). Cytogenetic studies revealed six of seven cases (all neoplasms) to have abnormal karyotypes. Special stains for organisms performed on smears from 25 cases including Ziehl-Neelsen, Gomori methenamine silver (GMS), Gram, and Warthin-Starry (WS) were negative except for 1/16 GMS and 4/9 Gram stains. In summary, we found that with appropriate case selection, ancillary studies performed on aspirated material can provide useful information in pediatric FNA cytology.     

Lack of selective Vβ deletion in peripheral CD4+ T cells of human immunodeficiency virus-infected infants

To investigate the possibility of superantigen-mediated deletions of T cells expressing particular T cell receptor Vβ (TcR Vβ) gene segments during human immunodeficiency virus (HIV) infection, TcR Vp usage in CD4⁺ and CD8⁺ subsets was analyzed in a cohort of infants maternally infected by HIV and in a group of healthy neonates. We used a semi-quantitative anchored polymerase chain reaction technique together with cytofluorographic analysis with anti-Vβ monoclonal antibodies. The representation of the 24 vβ families in CD4⁺ and CD8⁺ T cells from normal neonates was very similar to that in adults. Preferential expression of Vβ2 in the CD4⁺ subset was observed in both the neonates and in healthy adults. The representation of the 24 Vβ families in peripheral CD4⁺ T cells from the HIV-infected infants showed no selective vβ deletion, even when the CD4⁺ subset was globally depleted. Moreover, the main characteristics of the control group (predominance of certain Vβ families and Vβ2 skewing towards the CD4⁺ subset) were also present in all the HIV-infected infants.     

Remission of persistent childhood asthma: Early predictors of adult outcomes

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Anti-phospholipid antibodies following vaccination with recombinant hepatitis B vaccine

This study was undertaken to evaluate the possible role of hepatitis B recombinant vaccine inducing the synthesis of IgG and IgM anti-cardiolipin antibodies (aCL), antibodies against beta(2)GPI (anti-beta(2)GPI), lupus anti-coagulant (LA), anti-nuclear antibodies and antibodies against extractable nuclear antigens (anti-ENA). The study population consisted of 85 healthy students (63 female, 22 male; mean age 20.8 years), vaccinated with three doses of recombinant DNA hepatitis B vaccine. One month after vaccination with the first dose of hepatitis B vaccine a minority of vaccinated individuals showed changes in IgG or IgM aCL or anti-beta(2)GPI or LA activity (P < 0.001). Among subjects in whom changes of IgG anti-beta(2)GPI were observed, a significantly higher number of increased (8/85) than decreased (2/85) values were found (P < 0.01). Analyses of paired data showed that differences in aCL or anti-beta(2)GPI levels before vaccination or 1 month later did not reach statistical significance. In two people aCL transitorily reached medium positivity after the first dose of hepatitis B vaccine with a drop 5 months later. Similar evident anti-beta(2)GPI fluctuation was also observed in one person. Another participant was initially low positive for IgG anti-beta2GPI and the levels were increasing after vaccination. Two participants became positive for anti-nuclear antibodies during 6 months' follow-up. There were no sex-dependent differences in tested antibodies observed and no associations between levels of aPL and levels of anti-HBV antibodies. We conclude that HBV can induce aPL, although rarely. In genetically susceptible individuals or together with some other triggers such combination might confer the risk of developing a continuous autoimmune response in an individual.     

Lipoblastoma and lipoblastomatosis in infancy and childhood: histopathologic, ultrastructural, and cytogenetic features

Lipoblastoma is a relatively rare tumor that occurs in infancy and early childhood and arises from embryonic white fat. Although a benign tumor, lipoblastomas tend to recur and may resemble myxoid liposarcoma. The authors report 26 cases over a 15-year period at Texas Children's Hospital. There was a slight female predilection (14F:12M). The most common symptom was a painless mass with or without increasing size. The trunk, extremities, head and neck, retroperitoneum, inguinal canal, peritoneal cavity, and lung were the tumor sites. Most tumors were circumscribed lipoblastomas and the minority were diffuse infiltrative lipoblastomatosis. Reexcision for residual or recurrent tumor was necessary more frequently in patients with lipoblastomatosis. Histopathologic examination and ultrastructural examination revealed cellular neoplasms composed of immature adipocytes with relatively well-defined septa, frequent lipoblasts, a fine vascular network, and often a myxoid appearance resembling myxoid liposarcoma. Cytogenetics was performed in 4 cases with chromosome 8q abnormality being most common. The major concern with lipoblastoma in children is to completely excise the tumor to avoid leaving residual tumor and to prevent recurrences. Confusion with myxoid liposarcoma, well-differentiated liposarcoma, and typical lipomas may occur. Although asymptomatic, lipoblastomas may cause dysfunction of other organ systems due to mass effect. Complete surgical excision with at least 2 years of follow-up is the preferred therapy.