Persistent transfusion-associated infectious mononucleosis with transient acquired immunodeficiency.

Trauma and blood transfusion led to profound, persistent infectious mononucleosis in a 21 year old man. Splenectomy and trauma had apparently produced transient immune deficiency which was complicated by osteomyelitis of a fractured tibia. The transfused blood probably contained Epstein-Barr virus (EBV). Infectious mononucleosis had ensued 25 days after a blood transfusion was given, antibodies to EBV appeared in his serum, and the infectious mononucleosis persisted for nearly two years. His immunity returned gradually to normal, but because of nonunion of the fracture site, which was infected by Staphylococcus aureus, above-knee amputation was required. The acquired, transient immune deficiency to EBV and profound infectious mononucleosis seen in this patient is analogous to inherited, permanent immune deficiency to this virus in the X-linked lymphoproliferative syndrome.

Epstein-Barr virus infections in the X-linked recessive lymphoproliferative syndrome.

Prospective studies demonstrated variable phenotypic expression of the X-linked recessive lymphoproliferative syndrome (X.L.R.L.S.) in three brothers: (1) hypogammaglobulinaemia and subclinical Epstein-Barr-virus (E.B.V.) infection with antibody response to E.B.V.; (2) E.B.V. infection with defective immune response to E.B.V., fatal infectious mononucleosis (I.M.), and immunoblastic lymphoma; and (3) histiocytic lymphoma. Hypogammaglobulinaemia and measles pneumonitis had preceded infection with E.B.V. The diverse phenotypic expressions probably resulted from the varied immune response to E.B.V. Recombination of X chromosomes was documented by Xg-blood-group studies in a survivor. E.B.V. can induce fatal I.M. and malignant lymphoma in X.L.R.L.S., but an immune response to E.B.V. can be protective.

Cytofluorometry of lymphocytes infected with Epstein-Barr virus: effect of phosphonoacetic acid on nucleic acid.

DNA synthesis in Epstein-Barr virus (EBV)-infected lymphocytes was inhibited by phosphonoacetic acid (PAA) as measured by [3H]thymidine incorporation. PAA, at a concentration of 200 microgram/ml, inhibited [3H]thymidine incorporation by human umbilical cord lymphocytes infected with EBV strain P94 but had little effect on DNA synthesis in mitogen-stimulated cells. Transformed cell lines did not develop from infected cord cell cultures treated with 100 microgram of PAA per ml. Cytofluorometric analysis showed marked increases in cellular nucleic acid content (RNA plus DNA) as early as 9 days after infection of cord cells in the absence of PAA and before significant enhancement of [3H]thymidine incorporation became apparent. Moreover, EBV led to increases in cellular nucleic acid even when 200 microgram of PAA per ml was added to cell cultures before infection. The apparent discrepancy between results obtained by [3H]thymidine incorporation and cytofluorometry is explained either by significant inhibition of cellular DNA polymerases by PAA or by a block at the G2 + M phase of the cell cycle. The data suggest that EBV initiates alterations in cellular nucleic acid synthesis or cell division without prior replication of viral DNA by virus-induced DNA polymerases.

Replication of Epstein-Barr virus DNA in epithelial cells in vivo.

Epstein-Barr virus (EBV)-specific complementary RNA (cRNA) was hybridized in situ to oropharyngeal epithelial cells taken from patients with infectious mononucleosis. Cells from patients shedding virus in the throat hybridized signifnicant quantities of cRNA, whereas cells from EBV-negative sources did not. The degree of hybridization indicated a large EBV genome number per infected epithelial cell and suggested that these cells were the source of virus found in the throat. This finding may explain the presence of the EBV genome in the malignant epithelial cells of nasopharyngeal carcinoma.

Variable phenotypic expression of an X-linked recessive lymphoproliferative syndrome.

Investigation of a family with cancer in boys revealed that at least 20 males had the X-linked recessive lymphoproliferative syndrome. A variety of phenotypes occurred: aproliferative phenotypes consisted of aplastic anemia, agranulocytosis or acquired hypogammaglobulinemia; and proliferative phenotypes of B cells included disorders associated with the Epstein-Barr virus, American Burkitt's lymphoma, immunoblastic sarcoma of B cells, fatal infectious mononucleosis or plasmacytoma. The lymphoproliferative disorders observed in males could have resulted from an immunodeficiency to Epstein-Barr virus. The variable phenotypic expression could have resulted from individual differences in the viral dose, duration of exposure and age at which the boys were exposed to the virus. Aproliferative phenotypes such as acquired hypogammaglobulinemia could have ensued from excessive suppressor-cell activity on B cells, whereas proliferative phenotypes such as Burkitt's lymphoma or fatal infectious mononucleosis could have resulted from infection by Epstein-Barr virus and failure to stop proliferation of B cells.

Hematopathology and Pathogenesis of the X-linked recessive lymphoproliferative syndrome.

Subtle immunodeficiency to infectious agents including measles virus and ten Epstein-Barr virus (EBV) has been described in the X-linked recessive lymphoproliferative syndrome. This syndrome has affected six male cousins and possibly another boy. Three brothers died of an infectious mononucleosis syndrome, in a maternal cousin agammaglobulinemia developed three years after infectious mononucleosis, and two half-brothers of the Duncan kindred died of lymphoma of the brain and intestinal tract, respectively. In three of the boys, unusual measles viral infections had developed. Paramyxovirus-like particles suggestive of measles virus were seen at necropsy in the atrophic lymphoid tissue of two boys. Also, numerous plasma cells were seen in the brains, visceral organs and the thymus glands, and thymic-dependent lymphocytes were sparse in lymph nodes and spleen. The abnormal lymphopoiesis in the syndrome probably results from a subtle immunodeficiency, and concurrent measles and EB virus infections.

Subpopulations of human lymphoblastoid cell lines. Correlation with the expression of surface receptors and content of Epstein-Barr virus genome.

Forty lymphoblast cell lines derived from normal subjects, patients with infectious mononucleosis, leukemia, and Burkitt's lymphoma have been studied for surface receptors including surface Ig, complement receptors by the EAC rosette and fluorescent (Raji cell) techniques, and Fc (aggregate) receptor by direct and indirect immunofluorescence. Because of the B-cell tropism of the Epstein-Barr virus (EBV), an effort was made to correlate the expresion of various surface properties of lymphoblastoid cell lines with the content of EBV viral DNA as determined by complementary RNA-DNA (cNRA-DNA) hybridization on membrane filters or by DNA-DNA renaturation kinetic analysis. The only correlation established was with the Fc receptor determined by direct immunofluorescence. No correlation of EBV genome equivalents per cell with complement receptor or surface Ig was noted, suggesting that the expression of these receptors is not influenced by EBV viral DNA content. Subgroups of lymphoblastoid cell lines were on the basis of variable expression of surface receptors, designated B1, B2, B3, B4, and T. The distribution of lymphoblastoid cell lines into these subgroups were in the ratio of 14:4:1:4:1. The B1, B2, and B4 cell lines (except Molt 4F) were found to contain EBV. The B3 subgroup, for wich cell line 698 was the sole example, expressed surface immunoglobulins but no other B-cell characteristics, and H.S.B., a T-cell line, lacked detectable EBV.

Enhanced destruction of lymphoid cell lines by peripheral blood leukocytes taken from patients with acute infectious mononucleosis.

The cytotoxicity of peripheral blood leukocytes from normal human donors and from patients with EBV-associated infectious nomonucleosis (IM) has been determined for human lymphoid cell lines (LCL) containing Epstein-Barr virus (EBV) DNA. In a 51Cr release assay, mononuclear leukocytes from all donors are spontaneously cytotoxic. Leukocytes taken from patients within the first 2 weeks of overt IM are significantly more cytotoxic. This increased cytotoxicity declines to the spontaneous level as the disease progesses. The increase shows no correlation with the degree of lymphocytosis but a positive correlation with numbers of circulating atypical cells. The reaction is apparently not directed against histocompatability antigens, known EBV membrane antigens, or other characteristics of fresh human lymphoid cells. Susceptibility to damage is shared by bone marrow-derived (B) cell lines but not thymus derived (T) cell lines. EBV-gene products cannot be soley responsible for expression of the unknown characteristic. Transformation of B cells with EBV in vivo or in vitro, however, may trigger its expression

The immune response to infection with vaccinia virus in mice. II. Appearance of hypersensitivity, production of macrophage migration inhibitory factor and transformation of spleen cells in response to virus antigens.

The appearance of specific hypersensitivity to virus antigens was examined in mice infected intravenously with vaccinia virus. Both immediate hypersensitivity, transferable by serum, and delayed-type hypersensitivity, transferable only by cells, were apparent 8 days after infection and demonstrable for at least a further 130 days. Production of macrophage migration inhibitory factor by lymphocytes from infected mice was measured directly in terms of inhibition of migration by antigen or indirectly by determining the effect of soluble factors elaborated by the stimulated lymphocytes. The irregular results may have been the resultants of antigen-mediated macrophage stimulation, toxicity and induction of migration inhibitory factor. Transformation of spleen cells - presumably lymphocytes - from infected mice could be induced in vitro by virus antigens for at least 139 days after infection. Virus/lymphocyte interaction appears to be a particularly fruitful area for further study.

The immune response to infection with vaccinia virus in mice. I. Infection and the production of antibody neutralizing cell-associated and cell-free virus.

The onset, duration and magnitude of antibody responses to a poxvirus infection were examined. Mice were inoculated intravenously with the WR strain of vaccinia virus and developed pocks on their tails. The number of pocks was related to the size of the inoculum. Virus was detectable in the spleen and infected mice were subsequently immune to intravenous and intra-nasal challenge. Sera of infected animals neutralized both cell-free and cell-associated virus. Antibody against cell-free virus appeared first; maximum titres were reached sooner but were lower than those of antibody neutralizing cell-associated virus. Titres remained high for at least 100 days after infection.