Newer methodologies in immunohistochemistry and diagnosis

Pre-treatment serum IL-10 predicts the risk of secondary central nervous system involvement in patients with diffuse large B-cell lymphoma

BACKGROUND

As diffuse large B-cell lymphoma (DLBCL) is a very heterogeneous group of lymphomas, much effort has gone in trying to identify patients with increased risk for early death or secondary central nervous system (CNS) involvement. To better predict their outcomes, we measured the levels of various cytokines in serum samples of patients with DLBCL and analyzed their clinical outcomes.

METHODS

We measured the levels of seven serum cytokines at diagnosis in 313 DLBCL patients who were treated with R-CHOP. Their impact on clinical outcomes, including time to secondary CNS involvement and the 3-year overall survival (OS) rate, were analyzed.

RESULTS

The median age was 56 years (range, 16-86 years), and 177 patients (57%) were men. Secondary CNS involvement was found in 5.4% (16/294) cases, and time to secondary CNS involvement was significantly short in patients with elevated interleukin (IL)-10 (p = 0.012). With the 3-year OS rate of the whole cohort being 73.6%, serum levels of several cytokines, such as CCL3 > 4.0 pg/mL (54.3% vs. 76.1%, p = 0.001), CCL5 > 450 pg/mL (57.0% vs. 78.1%, p < 0.001), any expression of IL-6 (59.3% vs. 76.6%, p = 0.001), and any expression of IL-10 (68.2% vs. 84.5%, p = 0.001), showed prognostic impact. Higher expressions of these cytokines were associated with worse manifestations of clinical prognostic factors.

CONCLUSIONS

Our study revealed that some cytokines impact OS and secondary CNS involvement. Future studies are required to elucidate how these findings can be incorporated to the conventional prognostic factors for more tailored approaches.

Choroideremia: new findings from ocular pathology and review of recent literature

Histopathology of young individuals affected by choroideremia is rarely available to allow correlation with the clinical presentation. A 30-year-old man with choroideremia died in a motor vehicle accident and one eye was subjected to histopathological examination. Immunoblot analysis of protein derived from white blood cells of a living brother, also affected with choroideremia, confirmed the absence of Rab escort protein-1, the normal CHM gene product. Direct sequencing of the coding region and adjacent splice sites of the CHM gene was undertaken on genomic DNA from the living brother and revealed a transition mutation, C to T, in exon 6 (R253X) which resulted in a stop codon and was predicted to truncate the protein product. Histopathological examination of the eye of the deceased brother showed relative independent degeneration of choriocapillaris, retinal pigment epithelium, and retina, similar to observations in the mouse model of choroideremia. In addition, mild T-lymphocytic infiltration was found within the choroid. The ophthalmic features and the pathology of choroideremia are discussed in light of new findings in the current case.

Murine model of primary intraocular lymphoma

PURPOSE

Primary intraocular lymphoma (PIOL) is a subtype of central nervous system lymphoma. Although this lymphoma is rare, its incidence has tripled in the past 15 years. Currently, the only available model is a murine metastatic malignant lymphoma that occurs after intraperitoneal inoculation of Rev-2-T-6 lymphoma cells into newborn syngeneic mice. The current study was conducted to develop a new experimental model for PIOL.

METHODS

Rev-2-T-6 cells (0.5 x 10(5) or 1.0 x 10(5)) were inoculated into the vitreous of adult BALB/c mice. Mice were monitored clinically every other day and under fundoscopic examination weekly. They were euthanatized on weeks 3, 5, 6, 7, or 8, after inoculation. All eyes were processed for histology. Immunohistochemistry was performed with an antibody (p14) specific for Rev-2-T-6 cells. Cytokine mRNA expression (IL-2, -4, -6, -10, and IFN-gamma and CC chemokine receptor-1 [CCR1]) was assayed in the lymphoma cells by microdissection and RT-PCR. IL-10 and -6 levels in the vitreous were measured by ELISA.

RESULTS

Within 2 to 4 weeks, tumor cells from the vitreous migrate through the retina and gather between the RPE cell and retina. Rarely (>2 months after inoculation), Rev-2-T-6 cells may break through the RPE and infiltrate the choroid and sclera. Tumor localization was confirmed by immunohistochemistry. The intraocular lymphoma cells produce high levels of IL-10, IFN-gamma, and CCR1 transcripts. A high level of IL-10 was detected in the vitreous inoculated with Rev-2-T-6 cells.

CONCLUSIONS

The data suggest that RPE cells constitute a barrier to the spread of intraocular lymphoma. Intravitreal injection of Rev-2-T-6 cells is a novel model of PIOL in immune-competent hosts that will aid in understanding the molecular mechanisms of the disease.