Erik Svedmyr

Virologic, immunologic, and clinical observations on a patient during the incubation, acute, and convalescent phases of infectious mononucleosis.

One patient with infectious mononucleosis (IM) was studied from the probable time of Epstein-Barr virus (EBV) infection (38 days before the onset of clinically overt disease), during the incubation and acute phases, until 6 months after clinical remission. Analysis of spontaneous outgrowth of EBV-carrying lymphoblastoid cells, by limiting dilution on feeder layer cultures, showed that virus containing B lymphocytes are already present early during the incubation period. Also low interferon serum levels were detected early after infection, and only before the onset of clinical disease. All other studied clinical laboratory and virus-associated variables were within normal range during the incubation phase, but changed to a pattern characteristic of IM in parallel to the clinical symptoms. During the acute disease EBV-associated nuclear antigen (EBNA)-positive cells could be directly detected among the lymphocytes, and antibodies to EBV antigens appeared. Lymphocytes stained by monoclonal antibodies, detecting Ia-like determinants (activated cells) and suppressor cells, increased dramatically, in parallel to a strong increase of functional suppressor cell activity, measured by inhibition of blastogenesis and PWM-induced immunoglobulin production. During the acute phase there was also a decrease of spontaneous cytotoxicity against the NK-sensitive cell line K562, while cytotoxicity (spontaneous) against an autologous EBV-positive lymphoblastoid cell line (LCL) was detected only during this phase. These reactions correlated to the presence of blasts, and the autologous reaction was exerted mainly by Fc-receptor-negative cells. Lymphokine production in response to EBV antigens was also initiated during the acute phase. During the convalescence period the serological and cellular immune parameters adjusted to the pattern of a normal EBV-seropositive person.

Specific cytotoxicity of h-2 incompatible mouse lymphocytes following mixed culture in vitro.

SUMMARY C57BL spleen or lymph node cells cultured for 4 days with mitomycin- treated CBA or A. CA spleen cells were tested in vitro for cytotoxicity against CBA and A.CA fibroblastic target cells. It was found that the cytotoxicity of C57BL spleen or lymph node cells toward target cells of the same genotype as those to which they had been preexposed in such a mixed leukocyte culture was greater than the cytotoxicity toward the other target cell used. This finding shows that immunologically competent cells acquire specific cytotoxicity toward H-2-incompatible target cells carrying the stimulating antigen under the conditions of the mixed culture.

Sensitization of Human Lymphocytes Against Autologous or Allogeneic Lymphoblastoid Cell Lines: Characteristics of the Reactive Cells

Normal human peripheral blood lymphocytes were sensitized to autologous or allogeneic lymphoblastoid cells in vitro. Purified T lymphocytes were found to be able to respond both by performing DNA synthesis and by functioning as killer cells. Surface marker analysis of blast‐transformed lymphocytes in the in vitro cultures showed a high proportion (around 50%) of blasts lacking any surface marker attributable to b or T blasts; such ‘null’ blasts have previously not been found in conventional mixed leukocyte culture or after phytohemagglutinin or concanavalin A activation Since the ‘null’ blasts could be shown to be produced in a high percentage from originally almost pure sheep erythrocyte(SRBC) binding lymphocytes and displayed a similar killing capacity per unit cell number is SRBC‐binding lymphoblasts, we consider the ‘null’ blast to be of T origin.

Stimulation of Normal Lymphocytes with Autologous Lymphoid Cell Lines: Properties of Derived Killer Cells

Lymphocytes from normal adults, with or without serological signs of previous Epstein‐Barr virus (EBV) infection, could be stimulated to proliferate and produce killer cells by incubation with autologous EBV‐genome‐positive lymphoid cell lines (LCLs). The stimulated cells were most probably of T‐cell origin, although at the peak of stimulation many of them lacked the sheep erythrocyte marker. Direct effector‐target cell contact was necessary for lysis to occur The cytotoxicity of autologously stimulated (AS) lymphocytes was not restricted to EBV‐genome‐positive LCLs, nor to cell lines of hematopoietic origin It was equally broad if cells carrying complement receptor had been removed before stimulation Fresh lymphocytes, blasts induced by phytohemagglutinin or concanavalin A. and Burkitts lymphoma biopsy cells were resistant or considerably less sensitive Mouse cells‐even cell lines‐were resistant The sensitivity of target cells to lysis correlated positively with their capacity to block AS lymphocyte lysis of autologous LCLs in competition experiments The cytotoxicity of AS lymphocytes was blocked by EBV‐genome‐positive and‐negative cell lines, whereas the EBV‐related cytotoxicity of T cells from acute cases of infectious mononucleosis was blocked by EBV‐genome‐positive LCL only.

Diagnosis and subclassification of follicle center and mantle cell lymphomas on fine‐needle aspirates

Cytologic distinction between follicle center lymphoma (FCL) and mantle cell lymphoma (MCL) is difficult with cytomorphology alone and requires immunophenotyping. The current study describes the distinction between follicle center and mantle cell lymphoma made with fine‐needle aspiration (FNA) material.

Stimulation of peripheral human lymphocytes by autologous EBV genome-carrying lymphoblastoid cell lines.

Abstract EBV-carrying lymphoblastoid cell lines (LCL) can stimulate lymphocytes of the autologous donor [autologous stimulation (AS) assay] to blast transformation and generation of killer cells of broad-range cytotoxicity. We have tested the possibility of developing an EBV-specific AS assay for use in the demonstration of EBV-specific memory cells in the peripheral blood of normal donors. For this purpose, the stimulating lines were treated by heat and protein synthesis inhibitors to prevent the release of possible nonspecifically mitogeneic factors. Moreover, an extensive purification of the effector cells was achieved in the hope of removing a possible cellular contributor to the observed nonspecific cytotoxicity. None of these approaches was able to narrow down this nonspecific cytotoxicity to an EBV-specific response. We have shown that AS reaction (1) is not related to the release of lymphocyte mitogeneic factors by stimulating LCL, (2) is mediated by Fc receptor-negative T cells, and (3) does not require macrophage nor any other non-T helper cells.

Lymphocyte abnormalities predicting a poor prognosis in Hodgkin's disease. A long-term follow-up

Two hundred sixty‐two adult patients with Hodgkins disease (HD) were studied. Incorporation of carbon‐14‐thymidine was measured in unstimulated monocytedepleted lymphocyte cultures, and in cultures activated by concanavalin A (Con‐A) before institution of therapy in all patients. Total blood lymphocytes and T‐cell subsets were enumerated in the last 108 patients. Patients had significantly decreased total (CD3+, CD4+, CD8+) and relative (CD3+, CD4+) T‐cell counts compared with healthy controls. Stage IV patients tended to have lower total lymphocyte and subset counts than remaining patients. However, significantly reduced total lymphocyte and CD8+ counts were only observed in comparison to patients in clinical stage II. Thirty‐three percent of patients had an increased spontaneous and a decreased Con‐A‐induced blood lymphocyte DNA synthesis. Functional lymphocyte abnormalities were related to advanced clinical stage, high age, mixed cellularity, and lymphocyte depletion histopathology and presence of B symptoms. The 10‐year survival of patients in this group was 36%, compared with 62% for the remainder. In a multivariate analysis of the whole series lymphocyte DNA synthesis was besides age the strongest predictor of prognosis. In univariate analyses of the second patient series total lymphocyte, T‐cell and subset counts were related to prognosis. These relatively simple lymphocyte functional tests may help to identify young HD patients for whom intensive cytoreductive therapy with or without autologous stem cell support may be the best therapeutic option.

EBV-related cytotoxicity of Fc receptor negative T lymphocytes separated from the blood of infectious mononucleosis patients

Epstein-Barr virus (EBV) related specific killing was demonstrated previously in the T cell enriched subpopulations of blood lymphocytes of IM patients. In the present work we demonstrate that the cytotoxic cells belong to the Fc negative T subset. T cells in the blood of IM patients can be divided in 2 categories, 1 Fc positive with non discriminative cytotoxicity and the other, Fc negative with selective cytotoxicity against EBV genome carrying lymphoblastoid cell lines.

Fine-needle aspiration cytology and immunocytochemistry of soft-tissue extramedullary plasma-cell neoplasms

This study presents 19 patients with extramedullary plasma‐cell tumors diagnosed by fine‐needle aspiration (FNA) cytology together with immunocytochemistry. Eight patients had primary extramedullary plasmacytoma, while 11 patients had tumors secondary to myeloma. The most common localization was soft tissue (9 cases), followed by lymph nodes (5), scalp (3), and oral and nasal mucosa (2). All FNA smears were cellular, and 12 cases showed dissociated monomorphic plasma cells. Seven cases showed a dominance of immature bare nuclei, which made them difficult to diagnose conclusively using cytomorphology only. Immunocytochemistry demonstrated monoclonal expression of light immunoglobulin chains in all cases which, together with demonstration of CD 38 positivity and cytomorphology, allowed a conclusive diagnosis of plasmacytoma. Diagn. Cytopathol. 1999;20:120–124.

Fine-needle aspiration cytology and immunocytochemistry of Hodgkin's disease, suppurative type

We describe 3 cases of Hodgkins disease (HD) of unusual suppurative type, which were diagnosed on fine‐needle aspirates. The smears were dominated by neutrophils, macrophages, and cellular debris. Only a few large, atypical cells of Hodgkin and Reed‐Sternberg type were observed. The differential diagnoses of such smears include infectious mononucleosis, tuberculosis, metastatic lymph node involvement, non‐Hodgkins large‐cell anaplastic Ki‐1‐positive lymphomas, T‐cell‐rich B‐cell lymphomas, and peripheral T‐cell lymphomas of mixed type. Immunocytochemistry identified the large atypical cells as CD 30 (BerH2)‐positive and negative for CD 45 (LCA) in cytospin material from 2 patients, which allowed a conclusive diagnosis of HD. Diagn. Cytopathol. 1998;18:437–440.© 1998 Wiley‐Liss, Inc.