The establishment of an interleukin-6-dependent myeloma cell line (FLAM-76) carrying t(11;14)(q13;q32) chromosome abnormality from an aggressive nonsecretory plasma cell leukemia

A new myeloma cell line designated FLAM-76 was established from a patient with an aggressive nonsecretory plasma cell leukemia. The cell line exhibited morphologic features of flaming cells and contained an abundant eosinophilic cytoplasm with many dilated cisternae of rough endoplasmic reticulum. FLAM-76 cells were positive for cytoplasmic kappa (kapp)-type immunoglobulin but did not secrete it into the culture medium. The cells proliferated in the presence of exogenous interleukin-6 (IL-6) and more than 800 pg/ml of IL-6 was necessary for their continuous growth. The cells did not grow without IL-6, and they did not produce IL-6. Thus, the growth of FLAM-76 appeared to be regulated by the paracrine mechanism of IL-6. Alpha-interferon (alpha-IFN) inhibited the IL-6-dependent growth of FLAM-76 in doses greater than 1000 U/ml. FLAM-76 cells expressed CD38 (OKT10) and cell adhesion-associated antigens such as CD44 and CD54 (ICAM-1). Chromosome analysis revealed FLAM-76 to have a hypodiploid chromosome constitution with t(11;14)(q13;q32) abnormality, which frequently is seen in neoplasms of B-cell origin. Immunoglobulin (JH and Ck) gene rearrangement (but no BCL-1 gene rearrangement) was found in this cell line.

Effects of sex hormones on fulminant hepatitis in LEC rats: a model of Wilson's disease

LEC rats, which have hereditary hepatitis and have recently been proposed as an animal model for Wilson's disease, were examined to determine the effects of sex hormones on fulminant hepatitis. After the rats had undergone ovariectomies or orchidectomies (castration) and were compared with intact rats, the age at the onset of fulminant hepatitis was not substantially altered but the survival rates decreased from 50% to 12.5% for females and 75% to 14.3% for males, indicating that sex hormones did not influence the occurrence of fulminant hepatitis but influenced mortality due to fulminant hepatitis. When testosterone was administered to the ovariectomized or orchidectomized rats, the survival rate increased to over 90% in both sexes. In contrast, estradiol did not affect the survival rate of either sex but affected the onset of fulminant hepatitis. That is, with the administration of estradiol, the age at which serum GPT activity reached its maximum was delayed 4 weeks in ovariectomized rats and 6 weeks in orchidectomized rats as compared with intact rats. A similar but somewhat weaker tendency appeared in rats given progesterone. The results of our study indicate that sex hormones have no effect on the rate of occurrence of hepatitis but affect the progression of hepatitis. In particular, testosterone increased the survival rate of rats with fulminant hepatitis, and exogenous estradiol delayed the onset of hepatitis for several weeks.

Inhibitory effects of human interferons on the immortalization of human, but not rabbit, T lymphocytes by human T-lymphotropic virus type-I (HTLV-I)

The effects of human interferon (IFN)-alpha, -beta, and -gamma on the immortalization of human and rabbit lymphocytes by human T-lymphotropic virus type-I (HTLV-I) have been investigated. The immortalization of human peripheral-blood lymphocytes co-cultured with lethally X-ray-irradiated HTLV-I-producer cells, MT-2, was blocked in the presence of more than 40 u/ml human recombinant IFN-alpha or more than 200 u/ml human natural type IFN-beta. However, rhIFN-gamma did not block immortalization by HTLV-I even at higher doses. On the other hand, the presence of high doses of hIFN-alpha, -beta, or -gamma did not exhibit any biological effect on the immortalization of rabbit peripheral-blood lymphocytes co-cultured with lethally X-ray-irradiated MT-2 cells. Integration of the full length of HTLV-I genome was detected in every transformant by Southern blot analysis. All cell lines established were CD4+/CD8 divided by T-lymphocytes, except for one cell line of CD4+/CD8+. Morphologically intact HTLV-I production was observed by electron microscopy in these cells. Our results indicate that HTLV-I released under the strongly suppressed condition in the presence of IFNs remains active and able to immortalize T lymphocytes. It is also suggested that immortalization of human T lymphocytes by HTLV-I can be inhibited by the antiviral state induced by the treatment with low doses of hIFN-alpha and -beta, whereas immortalization of rabbit T lymphocytes is not inhibited because of the species specificity of hIFNs.

Gene rearrangement and overexpression of PRAD1 in lymphoid malignancy with t(11;14)(q13;q32) translocation

The proto-oncogene PRAD1 (parathyroid adenoma 1) on chromosome 11q13 was found to be overexpressed in all five B-cell lines with t(11;14)(q13;q32) translocation tested. One B-cell lymphoma and four myeloma cell lines with this translocation demonstrated more than 10-fold overexpression as determined by Northern blot analysis, when compared with normal lymphoid tissues such as thymus, spleen and lymph node. Hematopoietic cell lines without the translocation were also examined, but none of these demonstrated the overexpression, confirming that overexpression of the PRAD1 gene is associated with t(11;14) translocation. A truncated form of mRNA was seen in one of five cell lines with the translocation, SP-49. Hybridization with different regions of the PRAD1 cDNA revealed that the truncated form of mRNA retained the coding region but had lost the 3' untranslated region. Southern blot analysis demonstrated a gene rearrangement in this SP-49 cell line. To study the genetic alteration responsible for the truncated form of mRNA in this cell line, the rearranged allele as well as the germline allele were cloned. The restriction map revealed that the rearranged portion was at the 3' end of the PRAD1 gene, eliminating the mRNA-destabilizing signal AUUUA. Human-rodent hybrid cell analysis demonstrated that the region introduced 3' of PRAD1 was derived from chromosome 11, suggesting that the PRAD1 gene region is deleted at the 3' end. Over-expression of the PRAD1 gene in association with t(11;14)(q13;q32) translocation suggested that in these cases the regulation of PRAD1 was altered by the juxtaposed gene, most likely the immunoglobulin heavy-chain gene from chromosome 14.

Acute megakaryoblastic leukemia: establishment of a new cell line (MKPL-1) in vitro and in vivo

A megakaryoblastic cell line (MKPL-1) was newly established from the bone marrow of an adult patient with acute megakaryoblastic leukemia. This cell line grew in single cell suspension with a doubling time of 30 h and consisted of large primitive blasts with persistent development of giant cells carrying multilobed nuclei. MKPL-1 cells were positive for platelet GPIIb/IIIa (CD41) and GPIIIa (CD61), and expressed OKM5 (CD36), MY7 (CD13), and MY9 (CD33) antigens in the absence of erythroid and lymphoid markers. The cytochemical and morphologic characteristics of MKPL-1 were also consistent with those of megakaryoblasts. The cells did not, however, express ultrastructural platelet peroxidase which is considered to be another marker of the megakaryocytic lineage. Cytogenetic analysis of MKPL-1 revealed a model chromosome number of 92 with abnormal chromosomes including those found in the patient's bone marrow cells. Furthermore, MKPL-1 cells were serially transplanted into nude mice for nine passages with production of lethal tumors and leukemic manifestation. Thus, our megakaryoblastic cell line which can be maintained both in vitro and in vivo would be useful for further studies of the biology of megakaryopoiesis and megakaryoblastic leukemia.

Unidirectional distribution of mosaicism in chimeric rats

Experimental rat chimeras were produced by aggregation of eight-cell embryos from two inbred strains, ACI/Hkm and WKAH/Hkm, which differ from each other in their major histocompatibility complexes and coat colors, and their mosaicism was analyzed. The existence of the isozyme Es-1, a serum cholinesterase specifically produced by WKAH-derived cells, and the agouti coat color due to ACI cells, indicated that all of the rats analyzed were unequivocal chimeras. The proportion of ACI cells in the red blood cell populations of the chimeras varied from 45% to 98%, as determined with a fluorescence-activated cell sorter and a monoclonal antibody against class I (RT1) antigen. Digital analysis of the coat color revealed that the proportion of the ACI type of coat color ranged from 72% to 98% in these chimeric rats. Each phenotype expressed in the coat color was complex and varied in size. The ratios of red blood cells and the coat color inclined toward the ACI type of cell population. Conversely, the rate of the WKAH-cell-type population was less than 50%. A breeding test disclosed chimerism of germ cells in two chimeric rats, and there were more pups with agouti coats than with albino coats. Taken together, it was shown in most of the phenotypes analyzed that the ACI type of cells was predominant in all of the chimeric rats. We discuss the possible causes for this unbalanced distribution in the rats.

Useful short-range transport of mouse embryos by means of a nonfreezing technique

The survival of mouse morulae to be implanted on the uterine wall of a recipient after storage at 0 degree C in sucrose-containing medium has shown tendencies similar to those of blastocysts developing in vitro. The pregnancy rate, as defined by implantation sites per embryos transferred, has varied from 52.9 to 77.2% and decreased depending on the duration of storage (0 to 72 h), and was lower than the rate of blastocyst formation in vitro (57.2 to 87.3%). Regarding the birth rate, 56.0 to 59.4% of implanted embryos were delivered as live pups regardless of storage duration, with the exception of controls (78.9%, 0 h). Eventually, 37.0, 32.8, or 29.9% of embryos were obtained as live pups when preserved by our system for 24, 48, or 72 hours, respectively. This viable, highly reproducible nonfreezing technique is useful for embryo preservation. Embryos were transported to evaluate the efficacy of the nonfreezing method. Mouse morulae were kept in a thermos bottle filled with ice-water and packaged in polystyrene foam. The package was transported from Kochi to Sapporo, about 1300 km, within 48 hours during which it was possible to maintain 0 degree C in the bottle and deliver to most areas in Japan. After shipping, the survival of embryos was 46.8% for development to blastocysts in vitro, and 37.1% for the pregnancy rate, with a final birth rate of 14.1%. Transport factors other than storage may have contributed to the lower birth rate; however, our system is cheaper, more convenient, and more practical than others for short-range transport.

Establishment of a new Hodgkin's cell line (HD-70) of B-cell origin

A new Hodgkin's cell line, designated HD-70, was established from the peripheral blood of a 69-year-old man with Hodgkin's disease of nodular sclerosing type. The cell line grows in a single cell suspension and has a doubling time of 28 hours. The cells have a round or irregular nucleus or multiple nuclei in relatively abundant cytoplasm that is positive for acid phosphatase, alpha-naphthyl butyrate esterase, and periodic acid-Schiff stains. HD-70 cells are positive for CD30 (Ki-1/Ber-H2), CD15 (Leu-M1), and CD71 (OKT9) antigens and contain cytoplasmic immunoglobulin (Ig) (A, kappa). Southern blot analysis showed that the cells have Ig heavy and kappa light chain gene rearrangement and lack T-cell receptor gene rearrangement. Chromosome analysis disclosed that the cells have a human karyotype with complicated abnormalities, including a 14q+. Heterotransplantation of the HD-70 cell line into newborn hamsters treated with antilymphocyte serum produced massive tumors with remarkable fibrosis and collagen band formation. These tumors displayed histologic features similar to those of the nodular sclerosing type tumor of the patient. Such fibrosis production and collagen band formation in heterotransplanted tumors suggest that a certain cytokine that induces fibrosis might be produced by HD-70 cells. This cell line may be useful for understanding the biology and pathogenesis of Hodgkin's disease.

Cryptococcal pleural effusion in an HTLV-I carrier with Waldenstroem's macroglobulinemia

A 70-year-old woman with Waldenstroem's macroglobulinemia developed bilateral pleural effusions due to Cryptococcus neoformans. She was found to be a carrier of HTLV-I. It is speculated that the opportunistic infection occurred as the result of an impaired cellular immunity secondary to HTLV-I infection.

Segregation of Human T Cell Lymphotropic Virus Type I and II Infections by Antibody Reactivity to Unique Viral Epitopes

A recombinant protein of the human T cell lymphotropic virus type I (HTLV-I) gp46 outer membrane envelope, MTA-4 (residues 129-203), reacted by Western blot with sera from HTLV-I-infected individuals from the United States and Jamaica but not with 24 (10%) of 242 Japanese sera. A related gp46 recombinant protein, MTA-1 (residues 162-209), reacted with all 58 sera from HTLV-I-infected US and Jamaican individuals and 238 of 242 sera from infected Japanese (combined sensitivity of 99%). Neither recombinant showed reactivity to sera from HTLV-II-infected individuals or uninfected controls. The reactivity of recombinant proteins containing the region of HTLV-II gp46 analogous to MTA-1 was also evaluated by Western blot: GH2-K15 (residues 157-205) and GH2-K55 (residues 162-205) reacted with 88 (98%) and 89 (99%), respectively, of 90 sera from HTLV-II-infected individuals but not with sera from HTLV-I-infected individuals or uninfected controls. These recombinant proteins should permit the development of assays to unambiguously confirm and differentiate HTLV-I and HTLV-II infections.

Establishment and characterization of a thymic carcinoma cell line (Ty-82) carrying t(15;19)(q15;p13) chromosome abnormality

A new human cell line, designated Ty-82, was established from the pleural effusion of a 22-year-old woman with undifferentiated thymic carcinoma. This cell line consisted of primitive cells that were positive for alpha-naphthyl butyrate esterase and acid phosphatase. The cells were shown to express epithelial membrane antigen, but were completely negative for cytokeratin, carcinoembryonic antigen, glial fibrillary acidic protein, desmin, S-100 protein, lysozyme, Leu-7, HLA-DR (Ia), leukocyte common antigen, Ki-I antigen, T-cell antigens, B-cell antigens, myelomonocyte antigens, and Epstein-Barr-virus nuclear antigen. Electron microscopy showed that the cells were highly anaplastic, with no sign of cellular differentiation to any lineages. The Ty-82 cell line was found to have a karyotype of 46,XX,t(15;19)(q15;p13), being identical to that of the patient's tumor cells. Four of 5 nude mice inoculated sub-cutaneously with Ty-82 cells developed tumors which displayed a histological picture similar to the original tumor. Thymic carcinoma is a recently recognized entity, and its cellular and clinical behavior are poorly understood. The newly established thymic carcinoma cell line would provide a useful tool for the better understanding of this rare disease.

Immunoglobulin prophylaxis against HTLV-I in a rabbit model

We have investigated the protective effect of human T-cell leukemia virus I (HTLV-I) immune globulin (HTLVIG) against HTLV-I in rabbits. HTLVIG containing 77 mg/ml of IgG was prepared from pooled plasma from seropositive healthy persons. In the first experiment, four groups (A, B, C, and D) of three rabbits were transfused with 5 ml blood from an HTLV-I-infected rabbit. Groups A, B, and C were infused 24 h later with 10, 5, and 2 ml HTLVIG, respectively, while group D was infused with 10 ml HTLVIG 48 h later. Seroconversion for HTLV-I occurred in none of group A, one of group B, and all of groups C and D after 2-5 weeks. In the second experiment, four litters (E, F, G, and H) born to another virus-infected rabbit and consisting of 7, 5, 7, and 7 newborns, respectively, were used. Litters E and H were allowed to grow normally as controls, while litters F and G were given intraperitoneal inoculation of 3 ml/kg of HTLVIG weekly four times until weaning. Although three of litters E and H each seroconverted after 5-8 weeks, none of litters F, and one of litter G became antibody-positive after 10 weeks. Presence or absence of HTLV-I infection in all these animals was confirmed by transfusion assay or gene amplification. These results indicate that passive immunization protects rabbits against blood- and milk-borne transmission of HTLV-I.

Adult T-cell leukemia: structures and expression of the p53 gene

Experiments were undertaken to investigate a genetic event involved in leukemogenesis in adult T-cell leukemia (ATL). For this purpose, the p53 gene was chosen for study, since alteration of the gene has been found in a wide variety of human cancers. Structures and expression of the p53 gene in ATL cells were investigated by Southern and Northern blot analyses and a polymerase-chain-reaction single-strand conformation-polymorphism (PCR-SSCP) analysis. Either subtle alterations of the p53 gene or the absence of detectable level of p53 mRNA were found in 2 of 3 acute ATL cell lines and 2 of 12 acute ATL fresh samples. In contrast, no mutation was detected in 4 cases with less aggressive types of ATL (3 chronic and 1 smoldering ATL cases). Mutations found in acute ATL cells occurred in regions highly conserved in evolution and all the cells carrying p53 mutation showed loss of the other p53 allele. These results suggests that alteration of the p53 gene may contribute to progression of the disease in some cases of ATL.

Immunoglobulin prophylaxis against milkborne transmission of human T cell leukemia virus type I in rabbits

Prophylactic effect of human T cell leukemia virus type I (HTLV-I) immune globulin (HTLVIG) against milkborne transmission of HTLV-I was investigated in a rabbit model. Four litters (A-D: 7, 5, 7, and 7 offspring, respectively) born to an HTLV-I-infected rabbit were used. Litters A and D were allowed to grow normally as controls, while litters B and C were given weekly intraperitoneal inoculation of HTLVIG four times until weaning at 4.5 weeks of age. Only 1 (8.3%) of the 12 HTLVIG-inoculated rabbits, compared with 6 (42.9%) of the 14 control rabbits, seroconverted for HTLV-I. Gene amplification detected the presence of HTLV-I proviral sequences in all of the seroconverted but in none of the seronegative rabbits. These results suggest that passive immunization is effective in preventing dam-to-offspring transmission of HTLV-I.

Dexamethasone and phorbol ester, but not cytokines, increase the production of plasminogen activator inhibitor type-2 in the PL-21 human promyelocytic leukemia cell line

PL-21 is a promyelocytic leukemia cell line that produces plasminogen activator inhibitor 2 (PAI-2). Differentiation-linked expression of PAI-2 was investigated by adding cell-differentiation promoting agents [such as phorbol myristate acetate (PMA), retinoic acid (RA), dexamethasone (Dex), and recombinant cytokines, including tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta), granulocyte-colony stimulating factor (G-CSF), and interleukin-6 (IL-6)] into the culture medium of PL-21 cells. PAI-1 and PAI-2 antigens were measured by an enzyme-linked immunoassay. The PAI-1 antigen, however, became detectable only after stimulation. The presence of PAI-2 antigen was further verified by immunoblotting using a monoclonal antibody against PAI-2 purified from a PL-21 culture medium. PAI activity both in the culture medium and in the cell lysate increased approximately 70-fold after exposure to PMA. Both PAI-1 and PAI-2 antigens increased, but the amount of the latter in the culture medium and in the cell lysate was approximately 10 times and 2,500 times, as much, respectively, as that of the former. Dex also increased the intracellular PAI activity approximately 6-fold, parallel with PAI-2 antigen. PAI-1 antigen increased only slightly in the culture medium but not in the cell lysate after Dex-stimulation. As with the case of PMA, TNF-alpha and IL-6 induced PL-21 cells to macrophage-like cells, but did not affect the PAI activity. Thus, the increase of the PAI-2 production by PMA may not necessarily depend on differentiation into macrophages. Other cytokines examined did not increase the PAI activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Establishment of a new Epstein-Barr virus nuclear antigen-positive B-cell line, BALL-2, with t(8;14) (q24;q32) chromosome abnormality from B-cell acute lymphoblastic leukemia, L2

A new Epstein-Barr virus nuclear antigen (EBNA)-positive B-cell line, designated BALL-2, was spontaneously established from the peripheral blood of a 14-year-old boy with an EBNA-negative B-cell acute lymphoblastic leukemia (B-ALL), L2 in the French-American-British classification. The BALL-2 cell line grew in suspension with or without forming clumps of cells. The cultured cells exhibited lymphoid morphology with indented or lobulated nuclei, prominent nucleoli, and relatively abundant cytoplasm. Immunologic and cytogenetic studies showed that the BALL-2 cell line expressed the B-cell phenotype, CpIg+, SmIg+, CD19+, CD20+, CD38-, Ia+, and had chromosome translocation, t(8;14) (q24;q32). The same phenotypic and chromosome markers were present in original leukemia cells. These results indicated that the cell line was derived from the patient's leukemia cells. Unexpectedly, however, BALL-2 cells were positive for EBNA and EB virus DNA. Gene analysis of the BALL-2 cell line showed biallelic rearrangements in the JH locus. One of the JH rearrangement comigrated with a rearranged c-myc gene, indicating the translocation had occurred between JH and c-myc loci. The t(8;14) abnormality is a known chromosome marker of Burkitt lymphoma and L3 type ALL. Our studies revealed that this translocation and myc gene rearrangement can also be found in L2 type B-ALL.

Novel t(15;19)(q15;p13) chromosome abnormality in a thymic carcinoma

A 22-year-old female with a thymic carcinoma is reported. The tumor was refractory to both chemotherapy and irradiation. The patient died with an aggressive clinical course. Cytogenetic study showed that the tumor cells had a chromosome translocation, t(15;19)(q15;p13), which was not identified previously in human cancer.

[Clinical features of 32 cases of fungal pneumonia]

A total of 32 patients with mycoses other than cavity-formed aspergilloma were reviewed. The main pathogenic fungi were Aspergillus in 14, Candida in 8, Cryptococcus in 4, Trichosporon in 4 and Mucor in 2. Coinfection by two species was detected in 3 cases: Trichosporon and Aspergillus in 2 and Aspergillus and Candida in 1. The underlying diseases were hematologic malignancies in all cases except 1 case of lung cancer. The hematologic malignancies were mostly leukemias of various types. Cryptococcosis developed in patients given long-term corticosteroid treatment but not in leukemic patients. All cases of aspergillosis, candidiasis and mucormycosis were due to nosocomial infection. On the other hand, 3 of 4 cases of cryptococcosis or trichosporonosis were attributable to community-acquired infection. Two of 4 trichosporonosis cases were considered to have been acquired during 2-day home stays. The diagnosis of pulmonary mycosis was made pathologically in 18 and clinically in 14 cases. Of the latter, 6 cases had an air-crescent sign on chest X-ray films and 8 cases were culture-positive. Extrapulmonary involvement was seen in all 16 cases of candidiasis, cryptococcosis and trichosporonosis but not in 10 of 14 aspergillosis cases. Severe granulocytopenia was present in all cases except 4 cases of cryptococcosis and 3 cases of aspergillosis. Chest X-ray findings of aspergillosis were of two types: one was an air-crescent sign which was noted in the recovery phase from leukopenia and the other was gradually enlarging consolidation which was bound by the interlobar fissure and progressed to lobar penumonia. A diffuse granular shadow was not characteristic of any fungus species.(ABSTRACT TRUNCATED AT 250 WORDS)

A new monoclonal antibody to human subcapsular thymic epithelial cells

A monoclonal antibody, termed K-20, was generated against an anaplastic thymic carcinoma cell line, Ty-82. Subcapsular thymic epithelial cells of the thymus and blood vessels in various organs were shown to react with the K-20 monoclonal antibody by immunohistochemical staining. Immunofluorescent study revealed that various haematopoietic fresh cells and cell lines did not show any significant reactivity with K-20, except for one Epstein-Barr-virus-carrying lymphoma cell line (SP-50B). Western immunoblotting and affinity purification procedure revealed that K-20 was directed to a protein with a molecular weight of 28 kDa. K-20 is unique in its restrictive reactivity with human subcapsular thymic epithelial cells.

Molecular cloning of the chromosomal breakpoint of a B-cell lymphoma with the t(11;14)(q23;q32) translocation

The breakpoint of t(11;14)(q23;q32) chromosome translocation in a B-cell lymphoma line, RC-K8, was cloned. Immunoglobulin heavy chain (IGH) constant gene, C gamma 2 at the 5' end, was involved in this translocation, and the DNA segment juxtaposed to the C gamma 2 was proved to be derived from chromosome 11 by somatic cell hybrid study. The normal counterpart of chromosome 11 was also isolated. With a DNA probe near the breakpoint of chromosome 11, Southern blot analysis of RC-K8 and 10 other cases with translocation involving the 11q23 region was conducted, but no rearrangement bands have been observed thus far except for RC-K8.

Characterization of two human lymphoid cell lines producing human T-lymphotropic virus type I (HTLV-I) isolated from patients with HTLV-I-associated myelopathy or encephalopathy

Two cell lines, CNS-5 and CNS-6, were established by cocultivation of sedimented cells in cerebrospinal fluid (CSF) from two anti-human T-lymphotropic virus type I (HTLV-I) antibody-positive male patients with encephalopathy and HTLV-I-associated myelopathy, respectively, with peripheral blood mononuclear cells from a healthy seronegative female. These cell lines, possessing a normal female karyotype, revealed similar characteristics as follows; they expressed HTLV-I-related antigens, they produced C-type retrovirus particles, HTLV-I provirus genomes were integrated into their DNAs, and they had CD4+ activated T-cell markers. In addition, immunocytochemical and immunoelectron microscopic studies showed peculiar immunoreactivity of these cell lines with anti-alpha/beta T-cell antigen receptor (TCR) antibodies; beta Fl, defining beta chain epitope, was only positive in the perinuclear spaces and rough endoplasmic reticulum in some cells, and WT31, recognizing alpha/beta framework, was mostly negative, while CD3 was expressed in the majority of the cells. These facts indicate that HTLV-I-infected cells were present in CSF of these two patients, and suggest that neurological disorders associated with HTLV-I may not be restricted to myelopathy and may include brain abnormalities.

In vitro immunization of rat spleen lymphocytes with Forssman glycosphingolipid antigen and the generation of a monoclonal antibody

A procedure for in vitro immunization of splenic lymphocytes with a glycolipid antigen is described. Culture medium supernatant of ConA- and PHA-stimulated spleen cells and that of Con A-stimulated human Jurkat T cell line (IL-2-rich medium) were used as sources of cytokines to support T and B cell stimulation, and anti-mu was used to support B cell differentiation. Unprimed rat spleen cells (2 x 10(6)/ml) were stimulated with 2 micrograms/ml Forssman glycolipid antigen coupled to Sepharose for 4 days. The cells were fused with a mouse myeloma cell line P3-X63-Ag8-U1. At initial screening, 12% of the colony forming wells were secreting specific antibody. After cloning, a stable hybridoma cell line (designated 4C3) was established which secreted a monoclonal IgM antibody directed against the carbohydrate moiety of Forssman glycosphingolipid (GalNAc alpha 1-3GalNAc beta 1-3Gal alpha 1-4Gal beta 1-4Glc-ceramide).