CD74 expression in colorectal carcinoma, correlation with prognostic markers

This work aimed to study the expression of CD74, a protein which has an important function in antigen presentation by immune competent cells, in colorectal carcinoma to explore the feasibility of using it in antigen directed therapy in this type of cancer, we also aim to assess its prognostic value through studying its correlation with tumor grade, Ki 67 expression, and CD31 expression. Twenty three retrospective, formalin fixed, paraffin embedded specimens of colorectal carcinomas were graded using H and E stained sections after Bosman et al, [2010]. Specimens were stained using immunoperoxidase technique for CD74, Ki67, and CD31 antibodies, followed by semiquantitation of their immunoreactivities. The results were tabulated and statistically analysed using ANOVA test and Pearson's correlation coefficient. CD74 protein expression was present in 11/14 [79%] of adenocarcinoma NOS, with diffuse pattern of staining in all the positive cases except one case. The average weighted score [AWS] was 3.1: 4.5. CD74 was totally negative in mucin producing carcinomas [7cases]. CD74 was diffusely expressed in the studied case of neuroendocrine carcinoma but not in the case of medullary carcinoma. The correlation between CD74 and tumor grade was insignificant [p<0.2]. The average Ki-67 labeling index in colorectal carcinomas was 39%. The mean value for CD31 expression was 8.7: 14. Cd74 was positively correlated to Ki67 proliferation index [p<0.0004], as well as to CD31 expression [p<0.059]. Analysis of variance [ANOVA] for the three biomarkers [CD74, Cd31. Ki76] showed highly significant P value [p<0.000002]. In colorectal carcinoma CD74 expression positively correlates with Ki67 proliferation index and angiogenesis which suggests that it may be a marker of poor prognosis in such carcinoma. CD74 expressed in most of colorectal carcinomas suggesting the feasibility of using it in antigen directed immunotherapy in this type of cancer

Determination of laboratory reference ranges for lymphocyte immunophenotype subsets in healthy adult Japanese using flow cytometry.

This study represents a comprehensive evaluation of normative values for lymphocyte immunophenotype subsets using flow cytometry techniques in a Japanese population. Lymphocyte reference ranges were determined for percentage and absolute count of T, B, and NK cells in healthy adult Japanese using an extensive two-color immunophenotyping panel and consistently applied quality control methodology. Reference values were also determined for activation markers on CD3+ lymphocytes CD3+/CD25+, CD3+/CD38+ and CD3+/HLA-DR+. Differences in age and gender were observed for specific lymphocyte subsets. Comparison of the Japanese study with a Thai multi-center study that used similar methodology also demonstrated ethnic differences in lymphocyte reference ranges. The results in this study strongly suggest that reference values derived from studies in one population may not be applied to another population even when similar protocols for reagents, instruments and procedures are used although such studies do appear useful for epidemiological comparisons.

Longitudinal follow-up of lymphocyte subsets during the first year of life.

A longitudinal study of lymphocyte subsets during infancy was evaluated by using the flow cytometric immunophenotyping method. Two hundred and thirteen blood samples were obtained from 92 healthy, full-term infants of the following ages: 1-7 days old (n = 43), 3 months old (n = 55), 6 months old (n = 57) and 11 months old (n = 58). The absolute numbers of CD3+ and CD3+/CD4+ T lymphocytes increased from birth to 3 months of age, and remained stable thereafter. The absolute number of CD3+/CD8+ T lymphocytes increased from birth to 11 months of age. The absolute number of CD19+ B lymphocytes and NK cells increased rapidly (3 months) after birth and continued to increase throughout the study period. However, the changes in the relative counts of lymphocyte subsets did not always correspond with the changes in their absolute numbers. These results demonstrate the age-related changes in lymphocyte subpopulations and provide reference ranges for lymphocyte subsets during infancy.