Preferential selection of receptor-binding variants of influenza virus hemagglutinin by the neutralizing antibody repertoire of transgenic mice expressing a human immunoglobulin mu minigene

An analysis was made of the neutralizing antibody repertoire, for influenza virus hemagglutinin (HA) of transgenic mice expressing a human immunoglobulin mu (IgH) minigene, by monoclonal antibody (MAb) selection and sequencing of the HA genes of X31 (H3N2 subtype) laboratory variants. Whereas previously reported laboratory variants, selected in ovo with high-affinity murine MAbs of the IgG class, differed from wild-type virus by a single amino acid residue change in one of the major antigenic sites, neutralizing MAbs from transgenic donors selected novel variant viruses with altered receptor-binding specificity and contained residue changes in both the receptor-binding pocket (HA1 225 or HA1 226) and an antigenic site (HA1 135, HA1 145, or HA1 158). Changes in receptor-binding specificities of the variant viruses were confirmed by their resistance to inhibition by horse serum glycoproteins and altered binding to neoglycoproteins. The residue changes in variant virus V-21.2 (HA1 135 G-->R, 225 G-->D) abrogated neutralization by each of the MAbs; nevertheless V-21.2 was recognized by its own selecting MAb in enzyme-linked immunosorbent assay and therefore qualified as an adsorptive mutant rather than an antigenic variant. We consider that a low-affinity neutralizing antibody response may preferentially select for receptor-binding variants of influenza virus HA.

A Tertiary Care Center\'s Experience with Clinicopathological Characteristics of Gallbladder Carcinoma in Our Population

Introduction

Gallbladder cancer (GBC) is the most common malignant biliary tract tumor with the shortest survival from the time of diagnosis. This poor prognosis is due to the destructive biologic behavior of GBC, lack of sensitive screening tests for early detection, and vague nature of first presentation. Here in this study, we will evaluate the baseline characteristics of the patients presenting with gallbladder carcinoma in our population.

Materials and methods

This retrospective study was conducted in the Department of Gastroenterology at Sindh Institute of Urology and Transplantation (SIUT), Karachi. Patient data were compiled and composed from the in-patient health records, radiology, and operational records. Those patients with suspicion of GBC, but negative at histology, or patients having inconclusive radiologic findings, were excluded. Baseline characteristics were recorded. Results were presented as means ± SD for quantitative data or as numbers with percentages for qualitative data. Continuous variables were analyzed using the Student's t-test, while categorical variables were analyzed using the Chi-square test. A p-value of <0.05 was considered statistically significant.

Results

A total of 162 patients were included in our study. Among them, 101 (62.3%) were females. Hypertension was the most common comorbid illness noted in 29 (17.9%) patients while 91 (56.2%) patients had no concurrent comorbidities. Most common risk factor for carcinoma of gallbladder was gallstones seen in 106 (65.1%) patients. The most common presenting complaint was combination of obstructive jaundice, weight loss with right hypochondrial pain seen in 66 (40.7%) patients. On CT abdomen, direct liver infiltration without lymphovascular invasion was noted in 77 (47.5%) patients followed by liver infiltration along with lymphovascular invasion in 26 (16%) patients and distant metastasis in 24 (14.8%) patients. On gallbladder (GB) mass biopsy, 58 (35.8%) patients had well-differentiated, 46 (28.4%) had moderately differentiated, while 33 (20.4%) had poorly differentiated adenocarcinoma. Of 162 patients, 103 (63.6%) patients underwent endoscopic retrograde cholangiopancreatography (ERCP). The most common finding on ERCP was proximal common bile duct (CBD) stricture with intrahepatic biliary system dilatation which was noted in 95 (58.6%) patients. Percutaneous transhepatic cholangiography (PTC) was performed only in 9 (5.6%) patients. Seventeen (10.5%) patients were managed by simple cholecystectomy, 39 (24.1%) patients underwent extended cholecystectomy, 14 (8.6%) patients underwent chemotherapy, while 102 (56.8%) patients were given palliative management. When followed for 1 year, 101 (62.3%) patients died within 6 months.

Conclusion

The baseline characteristics, biopsy findings, modes of treatment, and rates of 1 year mortality were studied in patients with gallbladder carcinoma in our population. Advanced age, high white blood cell counts, and serum bilirubin at presentation with low lymphocyte count and presence of comorbid illnesses were the factors independently associated with increased mortality in patients with gallbladder carcinoma. However, further studies with large sample size and stratification with respect to age, gender, and different variables can be done in terms of mortality in patients with gallbladder carcinoma.

How to cite this article

Akbar N, Yaseen T, Muhammad A, et al. A Tertiary Care Center's Experience with Clinicopathological Characteristics of Gallbladder Carcinoma in Our Population. Euroasian J Hepato-Gastroenterol 2022;12(1):35–39.