CD79B mutations in primary vitreoretinal lymphoma: Diagnostic and prognostic potential.

OBJECTIVE: Primary vitreoretinal lymphoma (PVRL) is a rare type of lymphoma wherein the lesions are limited to the eyes. PVRL is difficult to diagnose because of the challenges related to obtaining sufficient samples for biopsy. Moreover, PVRL has poor outcomes and often leads to the development of central nervous system (CNS) lesions during its course. Two studies recently reported that approximately 70%-80% of patients with vitreoretinal lymphoma have MYD88L265P , which is frequently mutated in primary CNS lymphoma (PCNSL). PCNSL is closely associated with PVRL. The mutation of CD79BY196 has been also frequently detected in PCNSL. Thus, we examined the mutation in PVRL to clarify its diagnostic and prognostic potential. METHOD: By using direct sequencing and allele-specific polymerase chain reaction, we examined the mutation of CD79BY196 and MYD88L265P in the DNA extracted from the vitreous fluid of 17 patients with PVRL upon diagnosis. We also retrospectively analyzed their prognostic potential for PVRL. RESULTS: Among the included patients, six patients (35%) were found with CD79BY196 mutations. Twelve (71%) patients were positive for MYD88L265P , and six samples from patients with benign uveitis were negative for both mutations. Interestingly, six patients with CD79BY196 mutations developed CNS diseases significantly earlier (16.5 months) than 11 patients with CD79BWT (67 months; P = 0.0135). CONCLUSION: Detecting CD79BY196 in vitreous DNA may contribute to the confirmation of the diagnosis and may have a prognostic potential for patients with PVRL.

STAT3 is constitutively activated in chronic active Epstein-Barr virus infection and can be a therapeutic target.

Chronic active Epstein-Barr virus infection (CAEBV) is a lymphoproliferative disorder characterized by the clonal proliferation of EBV-infected T or NK cells and is related to severe systemic inflammation. This study aims to investigate STAT3 to elucidate the mechanism underlying the CAEBV development. We determined that STAT3 was constitutively activated in EBV-positive T- or NK-cell lines. We also determined that STAT3 was activated in the peripheral blood mononuclear cells (PBMCs) containing EBV-infected clonally proliferating T or NK cells in six of seven patients with CAEBV. We conducted direct sequencing of the STAT3 Src homology 2 (SH2) domain, which has previously been reported to be mutated in T- or NK-cell neoplasms. No mutation was detected in the STAT3 SH2 domain in patients with CAEBV. Next, we investigated the effects of ruxolitinib, an inhibitor of both JAK1 and JAK2, which phosphorylates and activates STAT3. Ruxolitinib suppressed the phosphorylation of STAT3 in EBV-positive T- or NK-cell lines. Ruxolitinib also decreased the viable cell number of EBV-positive T- or NK-cell lines and PBMCs from patients with CAEBV. Furthermore, ruxolitinib suppressed the production of inflammatory cytokines in the cell lines and CAEBV patient-derived cells. In conclusion, constitutively activated STAT3, which promotes survival and cytokine production, could be a therapeutic target for CAEBV.

[Ovum collection following ovarian stimulation in patients with chronic active Epstein-Barr virus infection].

The only curative treatment for chronic active Epstein-Barr virus infection (CAEBV) is hematopoietic stem cell transplantation. For young female patients, ovulation induction and oocyte cryopreservation may be performed prior to transplantation to provide for future pregnancies. However, the effects of this ovum treatment on CAEBV and EBV infections have not been reported. Attempts were made to collect ova from three female CAEBV patients before transplantation conditioning, but this was only successful in two cases. Ovarian stimulation did not induce disease progression, and there was no change in the peripheral blood EBV DNA load. In one patient, 460 copies/ml of EBV DNA were detected in the follicular fluid by real-time PCR. Red blood cells were also present in the follicular fluid but not mononuclear cells. EBV protein mRNA was not detected in the RNA extracted from the same fluid, suggesting that the EBV DNA resulted from peripheral blood contamination. Moreover, there were no EBV-infected cells in the follicular fluid. Therefore cryopreservation of oocytes from CAEBV patients is possible and may be used to provide for future pregnancies.

Virus-specific cytotoxic T cells in chronic active Epstein-Barr virus infection.

Chronic active Epstein-Barr virus infection (CAEBV) is a disease characterized by clonally proliferating and activated EBV-infected T or NK cells accompanied by chronic inflammation and T- or NK-cell neoplasms. However, the mechanism for developing CAEBV has not been clarified to date. Because the decreased number or inactivation of EBV-specific cytotoxic T lymphocytes (CTLs) resulted in the development of EBV-positive B-cell neoplasms, we investigated the number of CTLs in CAEBV patients using the tetrameric complexes of HLA-restricted EBV-specific peptides. Among the seven patients examined, EBV-specific CTLs were detected in the peripheral blood mononuclear cells (PBMCs) of four cases but were not detected in three cases. The ratio of EBV-specific CTLs in PBMCs tended to be higher in the patients with active disease than in those with inactive disease. In two patients in whom EBV-specific CTLs had not been detected, CTLs appeared after the eradication of EBV-infected T cells by allogeneic bone marrow transplantation. These results suggested that the failure of CTLs had a role in developing CAEBV, although the induction number and function of EBV-specific CTLs might vary in each patient.

Inflammatory cytokine production in chronic active Epstein-Barr virus infection.

In order to clarify the mechanisms underlying the development of inflammation in chronic active Epstein-Barr virus infection (CABEV), we examined cytokine production using patient samples. Eleven patients were analyzed. The serum concentrations of IFN-γ, TNF-α, and IL-6 were significantly higher in patients than in healthy donors. The mRNAs of these cytokines in peripheral blood mononuclear cells were elevated in patients as compared with healthy donors. The mRNA of IFN-γ was significantly higher in patients than in healthy donors. We examined which fraction produced the cytokines in the CD4-, CD8-, and CD56-positive fractions of PBMCs. The mRNAs of IFN-γ, TNF-α, and IL-6 were highly expressed in EBV-infected cells, whereas expression was also observed in non-infected cells. We performed in vitro infection of EBV on a T-cell line, MOLT4. EBV infection enhanced the mRNA expressions of IFN-γ and TNF-α. These results suggest that the inflammatory cytokines in CAEBV are produced not only by EBV-infected but also non-infected cells. EBV itself may have roles in the cytokine production observed in infected cells.