The lymph node pathology of Omenn's syndrome

Omenn's syndrome is a rare, usually fatal immunologic disorder of infancy characterized by recurrent infections, skin lesion, lymphadenopathy, peripheral blood lymphocytosis, and eosinophilia. Histologic evaluation of a lymph node revealed total effacement of the microscopic architecture resulting from a diffuse proliferation of interdigitating reticulum cells and a depletion of B lymphocytes. The lymph node lacked a distinct cortex and had no follicle formation. The most striking feature was a diffuse hyperplasia of S-100-protein-positive nonphagocytic reticulum cells with large, pale Langerhans-like nuclei. Ultrastructural examination identified these cells to be interdigitating reticulum cells. The lymphocytes were small and predominantly of the CD8 cytotoxic/suppressor cell type.

Antibody specificity for human immunodeficiency virus type 1 in serum and cerebrospinal fluid from patients with AIDS and AIDS-related complex

Since little information has been reported about the specificity of antibodies to human immunodeficiency virus type 1 (HIV-1) found in the cerebrospinal fluid (CSF), 21 CSF and serum specimens were examined from 19 patients with clinical AIDS, AIDS-related complex, or asymptomatic HIV-1 infection. The predominant specificity of antibodies using Western blot analysis in both serum (100%) and CSF (100%) was directed toward env gene products. The next most common antibody specificities were to the pol gene products (serum 95%; CSF 62%). Less commonly found was antibody to the gag-encoded proteins (serum 71%; CSF 38%). The level of antibody to HIV-1 in CSF could not be predicted from the level found in serum. Also, the spectrum of antibodies seen did not correlate with disease stage or with the quantity of antibody present. The serum/CSF pairs were also examined for the presence of HIV-1 antigen by commercial enzyme immunoassay. HIV-1 antigen was present in eight of 19 (43%) of the serum samples and five of 20 (25%) of the CSF samples tested.

Evaluation of three enzyme immunoassays for HIV-1 antigen detection

Three enzyme immunoassay (EIA) methods for the detection of human immunodeficiency virus (HIV-1) were evaluated. Serum or plasma samples from 22 individuals seropositive for HIV-1 antibodies were tested with the Abbott, Coulter, and DuPont kits for presence of HIV-1 p24 antigen. Another 12 samples were tested with two kits only. Discordant results were obtained with 9 of 34 (26%) HIV-1-antibody-positive patient samples tested. Most of these discrepancies were found in samples containing less than 30 pg/ml of HIV-1 p24 core antigen. A sampling of sera from normal blood donors and patients with infectious or autoimmune diseases revealed a low level of false positive reactions, especially with sera containing antinuclear antibodies or rheumatoid factor. Noteworthy is the frequency of false positive reactions seen with the DuPont EIA for HIV-1 p24 antigen. 18/111 sera (16.2%) containing auto-antibodies tested positively with the DuPont HIV-1 p24 antigen EIA. The nonspecific nature of the test reactivity for 9/10 of these samples was confirmed using an HIV-1 p24 antigen inhibition assay. These findings are discussed in light of the need for HIV-1 antigen detection in the clinical laboratory and of other methods for HIV-1 detection: the polymerase chain reaction and measurements of reverse transcriptase activity.

Early commitment to neoplasia in murine B- and T-cell lymphomas arising late in life

Lymphomas arise spontaneously in C57BL/10.H-2aH-4b (2a4b) mice greater than 1 year old. The purpose of this study was to determine when cells become committed to neoplasia and whether genes linked to H-2a or H-4b are a factor in predisposition to genesis of lymphoma. Following transplantation of a pool of spleen cells in large groups of mice, lymphoma incidence increased 1.8- to 2.1-fold and mean latent periods decreased, compared with those in controls. Lymphomas arising in mice that received the same pool of spleen cells often displayed identical rearrangements of genes for immunoglobulin and T-cell receptor. This finding indicates that the lymphomas were derived from expanding clones of cells present in the donor mice prior to transfer. The age of the donor mice determined the latency of lymphomas arising after spleen cell transfer. When donors were 3-4 months old at the time of spleen cell transfer, lymphomas were detected in the recipients 1 year later. When mice 1.5-2 years old were used as donors, tumors were observed 3 months after transfer. Almost all of these tumors were clonally related B-cell lymphomas. We conclude that the lymphomas seen late in life arise from premalignant clones of cells that have become committed to neoplasia in relatively young animals. These clones normally follow an indolent course and are manifested clinically only in old age. Neither H-2a nor H-4b alone appeared to alter susceptibility to the genesis of lymphoma in similar experiments with H-2a and H-4b congenic mice.

Analysis of a murine B cell lymphoma, CH44, with an associated non-neoplastic T cell population. I. Proliferation of normal T lymphocytes is induced by a secreted product of the malignant B cells

A non-neoplastic T cell population associated with a murine monoclonal B cell malignancy, CH44, was analyzed. Immunofluorescence on cell suspensions and immunoperoxidase staining on tissue sections using monoclonal antibodies to the antigens Thy1.2, Ly-1, L3T4, and Lyt-2 confirmed the presence of both TH (Ly-1/L3T4+, Lyt-2-) and Tc/s (Ly-1/L3T4-, Lyt-2+) T cell subpopulations. The non-neoplastic T cells were present in both a 0.6 and 2.1 g CH44-bearing spleen. T cells, not normally in liver in significant numbers, were found in liver tissue when the CH44 tumor cells were present. These data implied an active proliferation of the T cell populations within tissues containing the malignant B cells. Supernatant from an in-vitro-adapted cell line of CH44 (CH44.LX) was tested for its ability to induce proliferation of normal murine splenocytes and thymocytes. As assayed by tritiated thymidine incorporation, both spleen and thymus cells proliferated in the presence of CH44.LX supernatant. Although supernatant from two of nine other B cell lines was able to stimulate the proliferation of spleen cells, only CH44.LX could induce proliferation of thymus cells. Supernatant from the seven other B cell lines and three hybridomas had no measurable effect on either splenocytes or thymocytes in this assay. It is hypothesized that the presence of a non-neoplastic proliferating T cell population associated with a neoplastic B cell lymphoma during in vivo passaging of the tumor is the result of effects derived from a secreted product of the malignant B cells. Whether the T cells have any effect on the growth of the malignant B cells is not known.

Mixed phenotype lymphomas of B10.H-2a-H-4bp/Wts mice: characterization of component cell populations

Three murine lymphomas of H-2a origin were investigated. Each of these lymphomas was derived in B10.H-2aH-4bp/Wts (2a4b) mice after a hyperimmunization protocol involving sheep red blood cells. Analysis of cell suspensions derived from the splenic tumors revealed a mixed lymphoid phenotype of the total cell population. Both the T-cell and B-cell populations remained after multiple passages of the tumors in syngeneic mice. A multiparameter approach combining immunologic and molecular genetic techniques was taken to determine the malignant cell population within these lymphomas. This analysis included depletion experiments utilizing histocompatible (B10.A X 21M)F1 mice to distinguish normal host-derived cells from the malignant tumor cells, fluorescence-activated cell sorting of the two cell populations followed by in vivo growth of the sorted cells, in vitro and in vivo cloning attempts, and molecular analysis of genomic DNA derived from the splenic tumors for clonal rearrangements of the immunoglobulin heavy-chain and T-cell receptor loci. Each of the three lymphomas was shown to be a malignant B-cell tumor that has an associated nonneoplastic T-cell component. The nature and functional significance of the numerous T-cells present in the B-cell lymphomas remain unknown and are being investigated.

Cross-reactive idiotypes and common antigen binding specificities expressed by a series of murine B-cell lymphomas: etiological implications

A series of 27 B-cell lymphomas (designated the CH series), induced in B10.H-2aH-4b p/Wts mice by intense adoptive immunization with sheep erythrocytes, was found to represent a subset of the total B-cell repertoire. This subset was characterized by expression of a limited number of Ig heavy chain variable regions, as evidenced by the presence of cross-reactive idiotypes and common antigen binding specificities. Twenty-one of the 27 CH lymphomas studied were classified into five groups, defined by a particular cross-reactive idiotype; four of these groups were linked in a single network. Seven of 16 idiotypes defined by absorption analysis were present on lymphomas bearing either kappa or lambda light chains and so were localized to the heavy chain variable region. The surface Ig on 14 CH lymphomas was found to be specific for epitopes on certain erythrocytes (bromelain-treated autologous erythrocytes, sheep, and chicken erythrocytes) or E. coli. We propose that the CH lymphomas represent the malignant counterparts of a subset of idiotypically related, normal B cells in B10.H-2aH-4b p/Wts mice. Perturbation of this idiotype network, by hyperimmunization with an antigen for which some of the members are specific (sheep erythrocytes), increases the risk for neoplasia. Possible mechanisms for this are discussed.